DE2945322A1 - METHOD FOR PREVENTING LEAKING OUT ESCAPE OF TOXIC MATERIALS IN THE ENVIRONMENT - Google Patents

Description

PATENT LAWYERS Dlpl.-Ing. P. WIRTH ■ Dr. V. SCH MIED-KOWARZIK \ Dlpl.-lng. G. DANNENBERG Dr. P. WEINHOLD Dr. D. GUDEL J

335024 SIEGFRIEOSTRASSE β

335025 8000 MONKS 40

SK / SK!

NPD-1339-1 ι

Pedro B. Macedo

6100 Highboro Drive

Bethesda, Maryland 2003 ** / USA i

Theodore A. Litovitz

904 Devere Drive

Silver Spring, Maryland 20903 / USA

Method of preventing toxic materials from escaping into the
environment

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The removal of large quantities of toxic materials, such as high-level radioactive waste, which is stored in collection points for used up

5 reactor material are stored in the processing of consumed fuels from a nuclear power reactor or formed during the operation and maintenance of nuclear power plants is a particularly important problem with the use of nuclear energy. It is generally recognized that a there is a particularly promising solution, convert this radioactive waste to dry solids, thereby making them chemically, thermally and radiolytically would be stable.

5 The dry solid stability problem of radioactive waste is closely related to human safety on earth for a period of more than 20,000 years. Radioactive waste usually contains the isotopes Sr ⁹⁰ , Pu ²³⁹ and Ca ¹³⁷ , with a half-life of 28 years and 24,000

20 years and 30 years respectively. These isotopes alone mean a considerable danger to all life and must be brought into the dry solid form, which for thousands of Years is stable. The radioactive waste in solid form must be able to produce the radioactive isotopes for this

To keep immobilized for a period of time, preferably even in the presence of an aqueous environment. The radioactive waste are formed in high volume and contain long-lived, medium-lived and short-lived radioactive ions and some non-radioactive ions. These solutions can be highly corrosive

A) endeavor, and it is difficult, if not impossible, bring them in concentrated form for further processing or storage.

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The two most common types of commercial reactors, both of which produce low levels of waste, are boiling Waser Reactor (B.W.R.) (boiling water reactor) and the Pressurized Water Reactor (P.W.R.) (pressurized water reactor). In a typical P.W.R. circulates pressurized, light water through the reactor core (heat source) to an external heat trap (water vapor generator). In the latter, where primary and secondary flowable materials pass through impervious surfaces to prevent contamination are separated, the heat is transferred from the pressurized primary coolant to the secondary coolant, to generate water vapor to drive turbines to generate electricity. In a typical B.V.R circu-

i5liert light water through the reactor core (heat source), where it boils with the formation of water vapor, which leads to an external heat trap (turbine and cooler). In both In reactor types, the primary coolant is cleaned from the heat trap and returned to the heat source.

The primary coolant and the dissolved contaminants are activated by the action of neutrons. materials penetrate the primary coolant through corrosion of the fuel elements, the reactor vessel, the pipelines and others Plants a. The activation of these corrosion products adds radioactive nuclides to the primary coolant. Corrosion inhibitors such as lithium are added to the reactor water. The primary coolant in most P.W.R. systems a chemical additive * is used to control the reactivity!

(shim), boron, added. These chemicals are activated and provide radionuclides to the primary coolant. Fission products diffuse or leak out of the fuel assemblies and carry the primary coolant further: Nuclides too. The radioactive materials from all of these

35Sources are transported through the system and appear through leaks and vents in all other parts of the system as well as in the outflowing streams from the

* (to control chain reactions)

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act of the primary coolant method used. Gaseous and liquid radioactive waste to be treated within the plant, to reduce the radioactive nuclides, which are discharged into the atmosphere or water ⁵ in controlled and supervised conditions in accordance with the Regierungsvor- j fonts. ί

The main processes or operations involved in the treatment of liquid radioactive waste in nuclear power plants are Filtration, ion exchange and evaporation.

Liquid radioactive waste in a P.W.R. become habitii> Divided into five categories according to their physical and chemical properties, as follows: clean waste, dirty or mixed waste, waste blown down from the steam generator ("steam generator blow down waste "), waste accumulating in the outflow of the turbine (" turbine building drain waste ") and detergent waste.

Liquid radioactive waste in a B.W.R. becomes common divided into four categories according to their physical and chemical properties as follows: highly pure waste, 25 low-purity waste, chemical waste and Detergent waste.

The "liquid radioactive" waste from both types of reactors j are very dilute solutions of radioactive cations and! ^ other, dissolved, radioactive materials as well as undissolved

radioactive particles or finely divided solids.

A practical method for the removal of radioactive materials in dry solid form with high resistance against leaching and other forms of chemical attack would not only be for the removal of radioactive nuclear waste as well as for the production of radioactive sources which can be used in industry, medicine and in laboratories.

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Up to now there has been no practical, safe means of safely removing, storing and immobilizing harmful radioactive waste materials. The current ⁵ storage containers do not provide reliable isolation and immobilization of such radioactive materials, nor sufficient long-term resistance to chemical attack by the environment and insufficient stability to high temperatures.

At the moment there is little radioactive waste, i.e. that in Reaktof. waste generated by facilities, discharged in the following way:

A) The dead ion exchange resin containing the radioactive waste is mixed with cement and poured into 150-1 barrels

poured.

B) The bottom materials from evaporators, the radioactively contaminated boric acid and those used to regenerate the ion exchange columns solutions used are included with

20 cement powder mixed and poured into 150-1 barrels.

C) The filters containing finely divided forms of radioactive waste are usually embedded in cement in barrels.

25These cereal barrels become the storage for less radioactive people Waste transported and buried about 2 m deep in the ground. At least one of these camps is located in the Eastern states of the USA and is exposed to significant rainfall In Europe, these barrels are sunk in the sea. In both

3cIn cases, the water first corrodes the metal, then the cement and relatively quickly exposes the radioactive ions, to penetrate into groundwater or seawater. Since the bearings in the USA are only a little deep, the can get dirty Mix water easily with streams, ponds and rivers and

penetrate the ecosphere. One consideration with this The practice is the assumption that after sufficient dilution the radioactivity becomes harmless.

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Some of the most dangerous nuclear wastes are cesium and strontium, which are biologically similar to sodium and calcium. They have a half-life of 30 years, which shows that they do

For at least 300 years (ten times the useful life) of the ecosphere should be isolated. In Bikini Atoll, the experts assumed that after a few decades the The island would be habitable again if there were no nuclear explosions during this time, but the population on the

When ioInsel returned, her health was seriously endangered. In the meantime it has been recognized that the flora and fauna have again raised these radioactive elements to dangerous levels focus.

¹⁵ Therefore, the "safe" concentration of radioactive waste must be much lower than assumed levels, and a more permanent replacement for cement is required. In one aspect, the present invention provides a safe alternative for cement consolidation of low levels of radioactive material

²⁰ waste.

Another previously proposed way is the so-called dry solids fixation, which deals with the fixation of waste in jars by mixing with glass-forming preparations and Melting is employed to form glass. This possibility offers some improvement in isolation and reduced rate of release of the radioactive Elements if the outer covers or containers are destroyed. Furthermore, these glasses remain at high temperatures

³⁰ relatively more stable than plastic, and they are chemically more durable in salt solutions than 'metals. Suitable for this known process glasses with high chemical resistance and low alkali ion conductivity were at very high temperatures, for example 1800 ⁰ C and more, Herge represents. The previous methods using such However, high-melting, glass-forming preparations are economically inexpedient and pose serious dangers due to a possible volatilization of the harmful radioactive material

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rials. Further, the method of dry solid radioactive waste is limited and offers no solution to the high volume of liquid radioactive waste that consumed in the ⁵ operation and maintenance of nuclear reactors, by the current practice of storage of spent fuel in waters and recovery systems of Reactor fuels are formed.

Ό In view of the overall difficulty in handling Radioactive material and, in particular, the risk of its volatilization into the atmosphere has attracted attention directed towards the use of glass preparations with relatively low melting temperatures, i.e. on glass preparations

I5parate with an SiO2 content of only 27% by weight . While the problem of volatilization of radioactive materials is reduced, it is not completely addressed. Furthermore, the glass preparation obtained shows a significantly reduced chemical resistance and increased ionic

²⁰ diffusion velocities for the radioactive materials present in it. The higher this diffusion rate, the lower the ability of the glass to keep the radioactive materials immobilized in its matrix. For the long-term

²⁵ attitude radioactive waste glass, these known preparations are not suitable.

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In contrast to the embedding process, tn Gla.s create The method of the present invention is a control of radioactive materials that are at risk of volatilization at the high ones used in the embedding process Temperatures exists, creating natural hazards due to a possible escape of the volatilized, radioactive Material into the atmosphere and the need for complicated recovery and / or removal procedures and devices is avoided.

The present invention relates generally to a j

Concentrating and immobilizing toxic solids, such as j

! Mercury, Cadmium, Tellru, Lead, Insecticides and Poisons I.

j i5 and especially radioactive materials etc., for a j

J extremely long period of time. j

The present invention is directed in particular to i new glass objects which contain these toxic solids and have high mechanical strength and high chemical resistance to aqueous corrosion as well as sufficiently low coefficient values of radioisotope diffusion jj to protect the environment before the release of radioactive materials , such as radioactive isotopes, nuclear reactor waste j, etc., and which are concentrated in the glass objects! trated, immobilized and embedded and _{are suitable for} digging or sinking. The glass objects are made by separating the radioactive solids in a glass container and then heating it to remove non-radioactive volatile materials and non-!

.

radioactive decomposition products produced. The glass holders can be made of porous glass and can be used against J possibly contain porous or non-porous glass filling, which can preferably be finely divided or in 3b relatively large shape, e.g. as a single or several glass] rods can be present. The composition of the invention Glass objects are due to a radiation activity pt preferably over 1 curie, marked per ecm of object

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(With treatment according to the invention, highly diluted, radioactive ver waste for the purpose of concentrating and immobilizing the same for storage reaches the radiation activity The items received may not be worth 1 millicuries per ecm and may even be below 1 microcurie per cm of glass objects remain if for other reasons it becomes expedient to collapse the glass containers and to seal. When concentrating and immobilizing radioactive materials in dilute radioactive materials Waste, the glass container can be loaded up to 10 microcurie per ecm, or more, the loading usually takes place j but not more than 1 microcurie per ecm object.) That radioactive material is in the form of radioactive solids I

in one embodiment, the amount of radioactive material in the glass container is at least 1 ppb (parts per: trillion (billion) by weight) in solid | Form of a large number of radioactive elements, usually at least 5 and preferably at least 10 of the radioactive elements listed below. The new glass objects according to the invention should contain at least 75 mol%, in particular more than 89 mol%, SiO ₂ .

From a practical point of view, the upper limit of the in the The radioactive material contained in glass objects is determined to a certain extent by the following factors: ! tion, shape and type of radioactive material embedded in the glass object, volume fraction of the im

j 30 glass containers present pores, amount of any im j glass container present glass filling as well as the different:

methods used to embed the radioactive material in the glass container.

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: / iM " ^r " 29A5322 j

Radioactive materials that can be chemically bound or fixed in the glass or silica gel matrix, include radioactive elements (naturally occurring and

⁵ artificially produced isotopes that are present as liquids or solids dissolved or dispersed in liquids or gases) in the form of cations, such as rubidium, strontium, the lanthanides, e.g. La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tp , Dy, Ho, Er, Tm, Yb, Lu, cobalt, cadmium, silver, zirconia

ionium, molybdenum, technetium, niobium, ruthenium, rrjdium, \ palladium, tellurium, cesium, barium, francium, yttrium, radiua. and actinides, for example Ac, Th, Pa, U, Np, Pu, Am, Cm, Bk, Cf, Es; Cations. According to the invention, radioactive waste from nuclear reactors, processing methods from \

ts spent reactor fuel, storage sites of spent fuel and other processes that produce radioactive waste.

The present invention can be carried out in various ways will. A simple, extremely effective way is to remove the radioactive materials, such as radioactive nitrates, to deposit as a solid in a non-porous glass container, e.g. a glass tube with a minted opening, the container then by heating to drive off water and / or other non-radioactive, if any, more volatile Heat materials and then collapse the tube walls and remove the trapped radioactive solids to close. Heating can be done in such a way! take place that the solids separated in the pipe, e.g. . '»Nitrates with the formation of non-radioactive gases, such as stick- I oxides, which can be removed from the glass tube before closing. !

You can also have a non-porous glass container on one end 35 close and at least partially with a filling, e.g. porous glass particles, such as porous glass powder oda? säir Jcteine Glass balls, or silica gel in finely divided or fill another shape. Then that becomes the radioactive material

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containing flowable material to fill the spaces between the glass particles poured into the container, whereupon
to drive off the non-radioactive, volatile materials with or without decomposition of the components, such as nitrates, in the flowable material, and finally the glass container is heated around the pores in the container that may be present on the glass particles and in any pores contained, porous glass ι particles sealed, radioactive solids.

10In this case, provide the glass particles top \ contained areas on which the solids can be deposited, j and continue to support a control volatilization! to prevent the flowable material from breaking out of the pipe! to prevent during the heating stage. The porous glass!

i5particles provide further internal surfaces within the j Particle pores for the separation of additional, dissolved solids of the flowable material as well as external surfaces r for separating dispersed solids.

In another embodiment, a non-porous glass i

Containers with open lower and upper ends are filled with porous j or non-porous glass particles, which by means of I a porous structure, e.g. glass wool or a porous glass!

disk or such a rod, in the lower container section
25 are held to carry the glass particles in the container.
The flowable material containing the dissolved and / or dispersed radioactive solids is then poured into the
The upper or lower end of the container is poured in and runs through the bed of glass particles, the filtering effect of which removes the dis-3operated radioactive solids from the flowable material. The glass particle bed can contain glass particles with silicon-bonded cation exchange groups, e.g.
Alkali metal oxide or ammonium oxide groups contain.

3 ₅ Remove the porous, cation-exchanging glass particles
dissolved radioactive cations from the flowable material.
This can by one or more such beds after the for a filtration and / or an ion exchange with

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Several beds are passed through conventional procedures until the flowable material has the desired radioactivity is cleaned. When the ion-exchanging filter glass parts are loaded or their further use is no longer desired for any other reason, the Beds and the container containing them for expelling water and / or other non-radioactive volatile materials or gases, such as decomposition products, e.g. nitrogen oxides, and then the pores of the porous, the adioaktij ven cation-containing glass particles for fusing the j Glass particles are collapsed to make the radioactive solid- i! substances and / or cations that act on the inner and outer j j particle surfaces are deposited, to include what! j i5the glass container is collapsed to get around its entire ι close content; so the entire mass is converted into a prak- j ι embedded table-solid, leach-resistant structure, which is suitable for j * j long-term storage is suitable. ;

In another embodiment, the glass container itself consist of porous glass, and the radioactive, flowable material is introduced into the interior of the container and through the j Glass pores from the inner to the outer walls of the glass container j ters allowed to penetrate. The insoluble, radioactive solids originally dispersed in the flowable i? S material j j are deposited on the inner walls of the container, and the dissolved radioactive solids are J in the pores of the glass! ι stored in the container, which makes them after various)! drive, e.g. those of US Pat. No. 4,110,096, are eliminated j

I:

j: «i can. Then, the glass container can be as described above for stripping the j 'of the volatile materials, can be finally heated to collapse the pores and · i for collapsing the container and so a ij embeds the radioactive solids in the glass structure.! Before heating, the outer wall surfaces of the loading | Halters are washed in order to wash deposited, radioactive solids from the outer surface layer of the glass container, so that, after heating to collapse the pores and container, an outer coat ('fciad') free of radioactivity is obtained.

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AV _ __ ■■ _

The non-porous glass preparations used for the glass containers and / or the glass filling therein can be of any suitable type, but are preferably strong! » durable, resistant to leaching and chemical resistance. Any GIa r.prjiparat with these properties can be used, such as high silica glasses, e.g. Vycor and Pyrexi. Suitable glasses can contain at least about 70 %, preferably ^! at least about 80 % and in particular at least about 93 %, ίο contain silica. ^;

1

The in the inventive method as porous Glaspräpa-. rate usable preparations generally contain SiOg as Main component and have a large surface area. at

In carrying out the various embodiments of the present invention, the SiOp content of the porous glass or silica gel is expediently at least about 75 mol-94, preferably at least about 82 mol% and in particular at least about 89 mol% SiO ₂ . These glasses are, for example, in US Pat. No. 2,106,744, 2,215,036, 2,221,709, 2,272,342, 2,326,059,

2,336,227, 2,340,013 and 4,110,096.

The porous silicate glass preparations can also according to US Pat

3,147,225 can be produced by forming a finely divided silicate glass frit through a radiant heating zone conducts to make them flowable during free fall and a generally spherical shape due to surface tension forces accept what to keep them! tion of their vitreous nature and spherical shape cools. !so

ι Usually the porous silicate glass can be produced! by melting an alkali borosilicate glass, a phase, j separation into two interconnected glass j j phases and one phase, i.e. the boron oxide and alkali i ! j ", metal oxide phase, leaving behind a porous skeleton ' mainly from the remaining, silicate-rich glass. phase leaches. The essential property of the porous Glass consists in the fact that, after its formation, it has a large inner surface covered by silicon-bonded hydroxyl groups

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Contains surface area. According to the invention is preferred a porous glass is used, which is produced by phase separation and leaching is made because it can be obtained with a high surface area per unit volume and small Has pore sizes to give a high concentration of silicon-bonded hydroxy surface groups, and because that Leaching process to form the pores from hydrolyzed residues Leaving silicic acid groups in the pores, wodurclji the number of silicon-bonded hyd.oxy surface groups present is increased. When used as packaging, the porous borosilicate glass can be used in powder form as for packaging! used in chromatography columns or in a predetermined form, e.g. as plates, spheres or cylinders. j

:

It is advisable to use a glass preparation in the container Ϊ " that provides a shell or shell with little leachable S components, such as alkali metals or boron. If this is not possible or feasible, the glass container is expediently before or after collapsing in a second Glass containers of such a composition that they contain no or only small amounts of alkali metals or boron or other leachable components. In particular, types of glass with a very high silica content are used for both used the glass container as well as for the glass filling.

If tearing of the glass container is to be avoided if it contains a glass filling, such as glass particles, spheres or a glass rod, a glass is preferably used for the container which, after the separation stage, has a glass transition temperature of up to 100 ^° C. above the glass transition temperature of the container Has glass that is formed from the glass filling and the solids deposited in and on the same. For this purpose, such a container glass is preferably used which, after the separation stage, has a thermal expansion coefficient that is up to about 2 × 10 −8 per ^° C. below the thermal expansion coefficient of the glass that is produced by sintering the glass filling

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and the solids deposited in and on the same is formed. When determining glass transition temperature and thermal expansion coefficients can amount and type of in the pores of the (possibly used, porous) Solids deposited in the glass container and in the pores and on the outer surfaces of the optionally used porous glass filling as well as on the outer surfaces of a (possibly used) non-porous

ίο glass filling deposited solids have a significant effect on the glass transition temperature and the thermal expansion coefficient have and should be taken into account will. It is also expedient to cool the structure of the glass container and its contents after separation and sintering

is liert that the cooling rate in the entire structure from j Glass container and contents are as even as possible. Although i was found to have cracked in certain cases: this the goals according to the invention, namely the immobilization and isolation of radioactive solids from waste, which contain such solids in dissolved or undissolved form is not affected. !

In a method of the present invention, a radio-j active material as a solid in a hollow glass container \ is deposited with at least one opening. The radioactive material is deposited from a flowable material that runs continuously through the container or is added to it in batches. The flowable material can be dissolved j radioactive materials and / or finely divided radioactive!

Contain materials, and it can be a gas and / or a j! Be liquid. The radioactive materials used in the j to be treated, flowable material in finely divided or j dissolved form, can be on a non-porous or porous glass with an interconnected, porous

3b structure to be deposited. When using a porous In glass, the pores are usually smaller than the finely divided radioactive materials in the flowable material, thereby allowing their passage into the interconnected pores

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is prevented. In this case, the finely divided materials on the inner wall surfaces of the porous glassf container deposited. Dissolved or in the flowable material

i> gaseous, radioactive materials penetrate the glass pores a and are within the porous structure by reaction with the glass, by cation exchange with the glass or trapped by precipitation within the glass pores. When using a porous or non-porous glass the radioactive ones deposited in the hollow glass container Materials trapped within the glass matrix by the collapse of the container walls. The collapse of the container walls takes place by heating the container while a) is applied to the inside of the container, a vacuum, b) on the

if the container is applying external pressure, e.g. by placing | a weight or increase in gas pressure outside the; Container and c) a combination of methods a) and b) applies. When the radioactive material is deposited in the pores of a porous glass, the container will collapse the pores are heated before the container walls collapse.

The glass container is hollow and has at least one opening. For processing liquids, the container is preferably in the form of a test tube. If he's more than one opening, as in the case of a hollow glass rod (or tube), one or more openings can be made through a

i The glass stopper must be closed so that it is possible to use it intermittently

ι Operation the flowable material does not escape. A glass tube with an opening is used for continuous work

'30 preferred at both ends; Both openings can be closed with a porous glass stopper. The bigger that Volume of the flowable material to be treated, the more angular a continuous operation becomes. Other, Configurations of the glass container suitable for the present invention are, for example, U-shaped, cup-shaped or box-shaped Configurations.

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The simplest embodiment of the present invention j relates to the deposition of radioactive materials in a non-porous glass container with subsequent colla;

i beer of the container walls and burying or sinking the, j obtained glass object. The glass container can, for example, have the shape of a test tube and be made of a non-porous one Glass, such as Vycor glass (trade name of a heat and chemical resistant glass with low thermal expansion

ίο the company Corning Glass Works) exist. In another j Embodiment, the radioactive material is deposited in a porous glass container. In another embodiment form it can be deposited in a non-porous glass container; in which a second glass, e.g. a glass filling

iü ment is arranged. Furthermore, the radioactive material; deposited in a porous glass container in dom; a second glass or glass filling is arranged. In the two latter embodiments, the second glass can be a non-porous or porous glass. The second, porous or non-porous glass can be a glass preform of any suitable configuration (e.g., rod, parallelepiped, finely divided or spherical, etc.) to fit in and at least partially fill the glass container , however, the second glass is preferably in finely divided form, e.g.

as a ball, present. A preferred embodiment of the present invention uses a non-porous glass tube with a filling of porous glass particles. 1 Nuclear waste in a non-porous tube j A non-porous tube made from Vycor or silicate glass;

The hollow container is at least partially filled with a flowable material containing radioactive materials. In the case of the j container, an opening is preferably closed with a porous glass stopper. When the flowable material is a liquid such as water, the glass container is heated to dryness to evaporate the flowable material so that the radioactive materials are deposited on the inner walls of the container. Temperatures can be anything above the boiling point to about 50 ^° C. above the boiling point ^

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of the flowable material can be used. Lower temperatures can be used to dry the material when a vacuum is applied to the interior of the glass container. The glass container is further heated L, and at around 400 ° C, those originally present in the nuclear waste decompose. radioactive salts, e.g. radioactive metal nitrates, or they are formed with the formation of the corresponding oxides, e.g. the radioactive metal oxides, calcined. The non-radioactive, Gaseous decomposition products, such as nitrogen oxides, are driven off by heating, and the porous Stopper acts as a barrier to prevent nuclear waste from escaping from the glass container. The latter will Further heated until it collapses in order to keep the precipitated, crystalline core waste inside the sealed container to include. Before adding the flowable material in

• Silica and clay can be added to the flowable material in the glass container so that a calcined material is created after heating. It is known to calcine nuclear waste materials in metallic containers. The methods and operating conditions used can also be used when calcining the glass containers according to the invention and are hereby included in the present invention. Usually the glass tube collapses at around 1300 ^° C. For more details on the drying process,

Including the radioactive decomposition products and j Collapsing of the glass container are shown below.

• leads.

I nuclear waste in a porous glass container

The production of the porous glass containers used in the process according to the invention can be made by any suitable process! j to form a porous glass in any desired shape, j for example as a cylinder or cuboid. Its composition preferably contains more than 75 % silica. The porous glass is preferably made according to the method of US Pat. No. 4,110,096. For example, a glass preparation containing silica, boron trioxide and two alkali metal oxides (such as Na ₂ O and K ₂ O) is melted and made into long rods or

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Pipes pulled. By means of a suitable heat treatment, these rods or tubes can be phase separated into two Cause phases, namely in a silica-rich phase, which also contains small amounts of BpO, and alkali metal oxide, and a low-silica phase that contains larger amounts of BpO * and alkali metal oxide. Then the heat treated rods or tubes are immersed in a suitable leach solution, around the phase with the lower silica concentration

ίο remove. The removal of this phase and the subsequent one Washing provides a porous glass with an SiOp content of over 90 mol%, which is used as a glass container for embedding dissolved or gaseous radioactive material according to the present invention is suitable.

The present invention is further made with reference to a hollow, porous, test tube-like glass container described. A solution that is dissolved and finely divided, radioactive Materials, such as metallic deposits of platinum

Λ) containing metal families, usually present in nuclear waste solutions from spent nuclear fuel reprocessing plants, is poured into a porous test tube. The solution impregnates the walls and thus separates the dissolved radioactive material in the form of a "dopant" within the porous test tube walls. On the other hand, the finely divided, radioactive material does not penetrate into the walls of the glass container due to its particle size;:; f in, but is deposited by settling or filtration \ ^ on the ehälterinnenwand. The deposition on the inner container walls takes place by filtration and subsequent evaporation of the flowable material. j

The radioactive material originally present in the solution, on the other hand, is deposited in the container pores in dissolved form, for example as nitrate. Then the container opening is preferably closed with a porous or non-porous stopper, and the dissolved radioactive material is precipitated out of the solution according to methods, e.g. according to ** (see US Pat. No. 4,110,096, column 8, lines 15 to 21)

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of US PS A 110 096, deposited in the pores. The precipitation can be done by cooling the glass container (thermal precipitation) and / or by chemical precipitation. The chemical precipitation includes such a conventional ionic action to reduce the solubilities of the dissolved radioactive materials. It also includes an exchange of solvents to reduce solubilities for the purpose Precipitation. In this method, the porous test tube can be immersed in a solvent in which the soluble, radioactive material in the pores is less soluble. The addition of a suitable, with the

"dopant" or the dissolved radioactive materials in the pores reacting precipitant or an appropriate Changing the pH value is another means of chemical precipitation. This can also be achieved by evaporation of the flowable Material from the pores, preferably under vacuum and at temperatures around room temperature or below, effected will. Methods other than evaporation of the solvent as the sole means of precipitation are used when it is desired to obtain higher strength glasses. Combinations of precipitation processes, preferably one from thermal precipitation and precipitation by exchanging the solvents,

²⁵ can be used.

The separation of the dissolved, radioactive materials in the pores can also be achieved by cation exchange with the glass take place. The production of suitable types of glass for cation exchange and the precise description of the Cation exchange processes are described in the patent application filed at the same time (internal number NPD-1331-1) with deih Title "Method of air fixation of toxic materials in a { Glass matrix by ion exchange ", which is hereby included in the present application. A porous Glass containers with cation exchange capacity are particularly suitable for a continuous process. The solution ♦ (corresponding to US Ser.No. 959 222 of Nov. 9, 1978)

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35 _: "_"

is used for the purpose of cation exchange and inclusion of the dissolved, radioactive materials passed into the container interior through the porous walls, and then the remaining runs out Solution, i.e. the solvent such as water, through the outer container wall.

After the separation stage, the outer wall of the porous glass tube can be washed so that the in the pores of the

ίο deposited outer surface layers of the porous tube, Ground radioactive materials away. The washing stage is useful when making an item without or with only a small amount of radioactive material in the outer surface layers is desired

is and is not in the broad sense of the present invention essential. Then the solvent is preferably added to the solution without the radioactive material migrating over removes the pores, which can be done by drying processes according to US Pat. No. 4,110,096. The porous glass container will expediently placed in a drying oven and under vacuum at a rate below 100 ° C / h on an upper Heated drying temperature. In some cases, however, a higher heating rate can be used to j the throughput of materials through the treatment system j

to increase. j

After the tube has dried, two forms are obtained more radioactive! walls of the glass tube defined interior are deposited, and 2) the originally dissolved materials that in the Pores of the glass container walls are deposited.

After the drying step, continued heating of the glass container will cause the radioactive materials to decompose both in the pores and outside of them. For example, the radioactive material comes from its nitrate form (or any, original form) into the oxide, phosphate

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or silicate form / with the nitrogen oxide decomposition products being driven off. Be embedded Souen radioactive gases, such as krypton or iodine, this may in the pores of the <porous glass at a temperature, for example 50 to 150 ⁰ C below the glass transition temperature T, of the off

different materials containing glass tube are introduced.

The heating continues until the porous glass pores collapse continued. After that, the radioactive material including radioactive gases separated from the solution is complete enclosed within the glass matrix. It is chemically bound to the glass and physically in it

ib included. Heating can do that without great risk Lose radioactive material in the glass by evaporation because it is now trapped in the glass itself. During the f continued heating of the tube can mean a slight pressure difference between the inside and outside of the tube can be used to collapse the same. The pressure in the pipe is slightly lower than the pressure due to a vacuum set outside the tube so as to collapse the tube into a rod. To collapse the container walls can also external pressure from a weight placed on the pipe can be used. After collapsing the pipe (or other glass container) is the originally finely divided, radioactive material inside the preserved, sealed Glass vessel included. The originally undissolved, finely divided, radioactive, now enclosed in the glass vessel

. ", Ne material can be in elemental metal form or as a metal salt, metal oxide or other metal forms. A finely divided radioactive material which decomposes as described below would be in the oxide, phosphate or silicate form. The collapsed tube is a rod with two J _3b types of radioactive materials entrapped therein: 1) a material originally soluble in solution that gradually becomes chemically bonded to or entrapped in the glass, and 2) an insoluble, solid, radioactive material that is gradually trapped by the glass

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will. After the hollow glass object collapses, one obtains one that contains the originally undissolved, includes solid, radioactive materials enclosed in its core. The originally dissolved, radioactive Materials are trapped and immobilized in the glass matrix surrounding the core.

The use of a hollow, porous glass container, in particular in the form of a tube, offers an advantage over a porous gals rod various advantages. One advantage of a porous glass container in the form of a test tube is that it can be used of two surfaces, namely the inner and outer wall. The solution containing the nuclear waste is poured into the

_1b tube to enclose the finely divided radioactive materials and to penetrate the pores with the solution containing the dissolved radioactive materials. A solution that causes the dissolved radioactive material to precipitate in the pores can be introduced through the outer surface of the porous tube. For example, potassium silicate reacts with many nuclear waste (such as iron). The high pH value caused by the potassium silicate causes precipitation (eg iron oxide) within the pores. In the case of ruthenium, ruthenium silicate precipitates, etc. By introducing the material from the outer surfaces of the porous tube, controlled precipitation of the nuclear waste in the pores of the porous glass is enhanced.

Another advantage of pipe confugiation is that j

the dissolved, radioactive, nichi during the precipitation stage

falling materials can be sucked onto the inner wall of the pipe; thus the pipe is complete with the flowable, the material containing radioactive material is filled. Then it is put in clean water or a second solution, and a vacuum is applied to the inside of the pipe. In doing so, some dissolved, radioactive materials are carried through a decrease in temperature, by insolubility in the second solvent or by chemical activity with the same

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may not have failed. This dissolved, radioactive material that does not precipitate for any reason is sucked against the inner wall of the pipe, whereby the outer wall remains clean. This flow to the inner wall causes a distribution of the originally dissolved, radioactive material ("dopant" ^ which is higher on the inner pipe surface. When the tube finally collapses into a rod, it becomes a rod Area of high concentration of radioactive material enclosed in the entire glass system, creating a * =; height Concentration of nuclear waste on the exterior of the glass object can be avoided.

Another advantage of the tube configuration is that it confines any radioactive material, by decomposing the

is radioactive material formed during the drying stage Gases. If, for example, ruthenium tetraoxide is formed from the radioactive materials within the pores, it can consist of the tube center, from the drying / collapsing furnace and into another tube made of porous glass, which is at lower Temperature is to be aspirated. The radioactive gases are filtered through the second, proous glass tube; they react with the silicate of the glass and are precipitated within the glass pores. For example, rubidium is made from tetraoxide reduced to a lower oxidation state and precipitated within the pores. The second tube serves as a micropore filter. Its pores are collapsed, causing the pipe walls to collapse and so the gaseous, radioactive, enclosed and immobilized in a sealed glass matrix.

As can be seen, the porous glass tube can be used to absorb radioactive gases from radioactive disposal systems Waste that does not use porous glass containers can be used. Radioactive gases from other processing systems 35of nuclear waste can be treated in a porous glass filter will. The radioactive gases can be finely divided radioactive materials and gaseous radioactive materials contain. Non-radioactive materials such as water, etc.

030022 / 0S41

23: ■; ; -

go completely through the porous glass filters, while nuclear waste, such as ruthenium tetraoxide or cesium, is enclosed in the porous glass filter. If the filters ί> As they begin to lose their effectiveness, they can be heated by themselves to collapse their pores and walls. Be like that both the finely divided materials suspended in the gas and the gaseous, radioactive materials in the glass matrix trapped and immobilized. When using porous glass containers as filters, they do not need to be tubular to have; Flat configurations, for example, are equally suitable or sometimes even better.

Another benefit of using a porous glass container

is in contrast to a porous glass rod which is for one given thickness of the porous glass reduced processing time. For example, the one for the complete impregnation of a porous glass rod of 10 cm radius took the same time as for completely impregnating a porous glass container

2o with an inner radius of 10 cm and an outer radius of 30 cm. The glass container wall is 20 cm thick, but the impregnation is carried out on the inner and outer surface to a depth of 10 cm. For a glass rod, the cross-sectional area of the glass is only 100 Tf (or about 314) cm ² . For a glass container, however, the cross-sectional area of the porous glass is 800 7Γ or about 2514 cm ² or 8 times that of the rod. In this way, a significantly larger amount of glass can be impregnated in the same time unit. This benefit also applies during the drying stage and decomposition.

3o For comparison purposes, a shrinkage of the porous glass of 0 is assumed. When the glass container collapses, is the final diameter of the rod obtained about 28 cm. In contrast, the final diameter of a glass rod is with 10 cm radius at about 20 cm. So you get a bigger end

₃₅ Product with more radioactive waste in the same processing time when a glass container is used.

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- 26 -

Finely divided glass inside a glass container Finely divided glass in the form of non-porous or porous glass with interconnected pore structure or a mixture of both can be introduced into the glass container. The formation of non-porous glass particles is known and / are common Composition, or modifications thereof can be used. Porous glass particles are obtained from types of glass with a similar composition to the types used to make porous glass containers. The porous glass is preferably formed from preparations and by the methods of US Pat. No. 4,110.

is To make a pulverized glass, you can use the melted Glass can be poured directly into cold water to tear and break into small pieces; it can also become rods drawn or shaped into any desired shape. In the latter case, it is crushed in a grinding device.

20 reduced. The pieces of glass are sieved to get glass particles to obtain the desired particle size. Then the sieved particles are passed through a Flame headed. The advantage of making spheres instead of just using the sifted glass

2 ₅ with a random, irregular shape consists of a more uniform, greater filling density in the glass container. Thus, two types of glass particles can be made; one is simply broken up and sifted and therefore has elongated grains, of a random, irregular shape. The other type is crushed, sieved and remelted while passing through a hot zone and then rapidly cooled to form glass beads.

The particles thus obtained are non-porous and can be used in the ₃₅ embodiment where the radioactive material is deposited on non-porous glass particles inside the glass container. To make the non-porous glass particles porous, they are again about 2 hours to about 55O ⁰ C

030022/06 * 1

heated. This causes phase separation and leaching; (See U.S. Patent 4,110,096). The finished product is a wet, finely divided, porous glass in which the pores throughout the particle are in communication with one another and which can be used in the method according to the invention. Water is removed by heating the porous glass over 100 ⁰ C, and there is obtained a dry, finely divided, porous glass as a flowable, pulverulent product.

When elongated grains are used, the filling of the glass container may not be very effective, usually 60 % voids and the particles (or grains) only being present in 40 % of the internal volume of the glass container. On the other hand, round beads are easier to fill and usually result in fill quantities of 60 % or more. The ideal filling for beads is around 80%. An improved filling is obtained by applying pressure, whereby glass particles with a size between 5 microns and 5 mm,

20, preferably 50 microns to 1 mm.

The loading of the glass container can take place in the manner described here or in any other suitable manner.

The drying stage can be carried out in various ways. First, glass wool or a porous sheet of glass or other type of porous lid can be placed on top of the glass particles be placed in order to avoid their vertical movement when expelling the gases from the radioactive waste contained therein. Furthermore, a reasonable distance can be left at the container head so that the glass particles are drifted off move the gas upwards and then lower it again when the gas flow is interrupted. It is also useful to use the included Drying gases and glass particles through a relatively small heating zone located down from the head, so as to drive the gas progressively from the head to the ground. If, on the other hand, very strong heat or heat is applied to the ground, boiling can occur inside the container near the bottom, that blows out the glass particles on the head. Purpose-

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ΊΑ : i

The upper part of the container is kept moderately above 100 ° C. This process can be relatively rapid so that by heating from the head and bringing the heat down, all of the water 5 in the container can be gradually evaporated. If a layer of porous glass particles is then dried on the head, it is kept in the temperature range from 100 to 150 ^° C. in order to prevent other, toxic gases from escaping. Non-radioactive nitrate decomposition vapors in the container can escape through the dry porous layer, while the cfoium, sodium and other radioactive isotopes such as cadmium are retained in the porous sieve. If the water is evaporated once from the entire column, it can be heated quickly enough to a temperature of 400 ⁰ C to the Destil- ₁₅ lose to avoid the radioactive nitrates. At such temperatures, decomposition begins and nitrous oxide vapors are driven off. Again, ruthenium tetroxide can be a problem because one must avoid its escape from the container head by keeping the layer of porous glass particles in the head hot enough to allow water vapor to escape but cold enough so that RuO ^ remains in the container while the nitrate decomposition continues . As long as the vapors from the nitrate decomposition continue, the material is under high oxidizing conditions and there is not much possibility that ruthenium will be reduced to a lower, less volatile, oxidation state.

After the nitrate decomposition has ended, a vacuum can be applied to the inside of the container, with the increased temperature

^ is maintained to keep the oxygen vapor pressure sufficient to decrease, so that ruthenium tetraoxide spontaneously in a lower oxidation state with high temperature characteristics or very low vapor pressure, so as to permanently lock the ruthenium in the glass. The vacuum should

₃₅ before the porous glass actually begins to close its pores under heat, because under such conditions one can also reduce the amount of dissolved gas in the end product. A reduced amount of gas in

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each pore of the glass actually reduces the amount of soluble gases in the glass. The temperature is then increased and whenever there is a pressure jump, a vacuum is applied until the pressure slowly drops again. The tube collapsed around 1300 ⁰ C, the exact temperature of the furnace configuration, the container pore size, the type of finely divided glass depends so on. If the container walls are thin, they will collapse into a flat or elliptical cross-section and form a ribbon rather than a rod. If the walls are thick, a rod-like cross-section is more likely to be obtained. A further benefit of the rod-like cross-section is the pulling of the container when it is heated so that it is stretched during the collapse. For more convenient stacking or filling of the finished glass objects, a rod-like cross section can be more favorable for storage. However, if heat transfer is a major problem, it may be more appropriate to work with flat, ribbon-like cross-sections to promote this heat transfer. By using a narrow heating zone and moving it up from the bottom, an area near the head is reached where no glass particles are left and the glass container collapses on itself, further improving the sealing of the nuclear waste.

If the degassing is done properly, there will be very little bubbles and a finished product will be obtained with a shell made of a radiation-free glass with a low temperature expansion coefficient, which a glass with a high Includes temperature expansion coefficients. This creates pressure on the outer layers of the glass and tension inner glass core. If the inside of the glass is relatively free of bubbles, then it can withstand the tension and deliver as the end object a strong, pre-"stressed" material with a significantly higher tensile modulus than tempered glass. The advantages of a Monolith shape of the finished product are as follows: 1) is the outer surface area of the monolith glass much smaller than with discontinuous form, and there

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The amount of leaching is proportional to the surface area, the risk of leaching is significantly reduced; 2) if if there is no nuclear waste in the outer container layers 5, it is in the initial period of the leaching conditions no nuclear leachable waste available until, if that ever happens, leaching through the thickness of the outer layers of the collapsed container free of radioactive waste can penetrate. The latter can be very long

relative duration are accepted in comparison with the / short Ha ^"1 bwertzeit trapped in the container, radioactive isotopes, whereby they are embedded for the duration of their radioactivity and penetrates no radioactivity in the biosphere. width has the processing according to the invention of nuclear waste the advantage that it does not use furnace electrodes which can be corroded by the molten glass, no radioactive element gases are emitted, and generally very clean operation is possible. If a glass container breaks, the glass can be disposed of by breaking it into particles or remelting and processing it into particles as described above which are sealed in another glass container so as not to create new waste which requires a separate disposal system.

A monolithic (not finely divided) porous glass rod or similar, containing a radioactive waste solution The preform tends to break when heated because internal pressures build up due to evaporation of the internal water.

Very strong internal pressure can be sufficient to cause the glass preform to break. After removing the largest Some of the liquid will shrink the preform as it dehydrates, and if the dehyration is uneven, it will develop unequal loads while breaking the fore

_J5 shape when one side shrinks more than the other. At slightly higher temperatures used to decompose the salts, such as nitrates, gases such as nitrogen oxides are released, with the release of such gases being too rapid

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The preform, in turn, can break.

If further the material in the monolithic, porous glass rod

5 or a similar preform is deposited unevenly, the deposited material increases the thermal expansion coefficient of the silica component of the glass preform, and after the pores are collapsed by heating, the unequal expansion coefficient can lead to breakage. That Distribution profile of the deposited material in the monolithic Glass preform must be controlled very carefully to avoid breakage. These problems become significant reduced or eliminated by using porous glass particles in a glass container. The individual particles are

is so small that the stresses built up in them when they are heated not enough to break them, and even if some break it is of little consequence, and heating can be done much faster. Also the cross-section of the distribution profile of the deposited material in the end product is important. In the case of a non-porous glass container the outer layers of the end product have the inner coefficient of thermal expansion of the container, which is equivalent to a lower coefficient of thermal expansion than the glass particles inside can be made. So shows the end product in this case has a compression on the surface that makes it stronger.

The use of a glass container with porous and / or non-porous uniform particles has the further advantage that

30 separated, radioactive solids in the entire pipe interior instead of only on the inner surface of the container walls (when using a glass container without glass filling) or spread on the outer surface of a porous glass rod (if one is used). When using

_{In the case of} a non-porous glass container filled with glass particles, the clad obtained is also free of radioactivity and there is practically no risk of environmental pollution by radiation.

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31 *

When treating glass containers according to the invention, gases can escape from their open ends. A convenient way to control these gases is to use the Einf> Guide a porous glass layer into the open end of the container. It acts as a molecular sieve, and because of its very high initial surface area, e.g. 100 m / g, will be the attempt to escape from the container Gases trapped by the layer. Due to temperature con

The passage of j can troll the porous glass layer Water, non-radioactive nitrate decomposition products and other non-radioactive gases that you want to drive off, allowed, while at the same time ruthenium, cesium, cadmium and other radioactive materials in the container |

υ, to be closed. Temperature differences along the container can advantageously be used to drive off the non-radioactive volatile materials, while preventing the radioactive materials from escaping.

It is also useful if you turn the container into a rod of small dimensions or a band only one small dimension, e.g. its thickness, and a larger one

j width can collapse. The smaller dimension facilitates more uniform heat removal, ie it reduces the temperature gradients in the resulting glass and reduces or avoids cracking. Non-porous glass filling

In addition to or instead of the above-mentioned porous glass particles, the glass container can also contain non-porous Glass particles are filled. The non-porous glass particles can be made from any suitable glass preparation according to the

[conventional methods described above in relation to porous glass particles are produced, but with self- understandably in this case the phase separation and acid leaching are not necessary. Therefore, the non-porous glass particles in the form of spheres, elongated grains, or any other suitable shape

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and in the glass container in practically the same way as that
porous glass particles can be used, however
there are no pores into which the dissolved radioactive materials can penetrate. Therefore, solved and unresolved,
radioactive materials on the peripheral or external
Surfaces of the particles deposited, and when connecting-! The oxide forms of radioactive materials react to heating;

■ lien with the molten, non-porous glass particles and j i j

j ίο become an integral part of the final glass product, while:

I other forms are deeply involved in the same. In '

j I

: in many cases a moving heat is preferred- j; zone is used with a differential pressure, which can be achieved by evacuating the interior of the container or by applying a higher, ', ! ib external pressure, for example by mechanical means or gases ^{: is} formed.

_; It can also be useful to have a moving heating zone:

i to progressively collapse the container from bottom to i

Use j 20 above. If the container is very long, it will last

\ His weight may not be off if only he is at his

j upper ragions is supported, and can also be used on \

j floor be supported so that it is during the collab

• rens not long. However, should the pipe be stretched in order to ^!

? 5 to a stick and not to a flat block to kolla-; ι!

j beers can have a slight pulling force from the bottom of the container; I (in addition to gravity) and results in j

i:

j a stick-shaped object. ;

j 3o To prevent the glass container surrounding the glass filling from tearing
; To prevent this from happening, it must have a lower coefficient of thermal expansion than the included one
Have glass that after heating the glass container and
its contents containing the deposited radioactive materials for the purpose of sintering the glass filling to form ^; an enclosed glass loaded with radioactive materials is obtained. Silicate glasses with or without small amounts of boron (eg Vycor) have low thermal expansion coefficients, and they are increased with increased alkali metal content
the expansion coefficient also increases. The container

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also the expansion coefficient. The container preferably does not collapse prematurely, even with the interior under vacuum and the exterior under atmospheric pressure at temperatures at which the enclosed glass filling begins to melt, so that it remains a container containing the enclosed glass until the container collapses advantageously is. For this purpose, a container with a higher glass transition temperature, expediently silicate glass and Vycor, is preferably used. D i j particles of the glass filling ezUtzt, then degas as solid objects below the glass transition temperature or, as long as the glass is not so hot 1st even immediately above the same, that the particles coalesce with each other. At a slightly higher temperature, the glass particles fuse into one another, ie they coalesce, and become a uniform glass body which, if you proceeded correctly, is free of bubbles. When the container collapses at a temperature slightly above the T of the inner molten glass (including the deposited contaminants), a bubble-free final glass product containing the nuclear waste is obtained. However, if the container does not collapse until it reaches a much higher temperature, then there is a risk that the solubility of gases such as oxygen inside the molten glass will decrease to a point where the gas content, e.g. oxygen, will decrease its solubility in the molten glass Glass exceeds because it is under the vacuum used to collapse the container. If the gas content (oxygen) survives its solubility at the temperature and reduced pressure of the inner molten glass from the container collapse, bubbles and foaming may appear in the inner molten glass. When the tube collapses be subject to I _n Neren no longer a vacuum but a eii outer pressure; This increases the solubility of the gases in the internal molten gas and reduces the risk of bubbles or foaming. Prevention of bubble or foam formation requires a fairly precise choice

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the glass transition temperature of the container and the inner glass preparation containing the deposited radioactive solids contains. Is the inner glass preparation for Vycor or one melted silicate glass container too soft, then the The collapse temperature of the container can be reduced by using a container glass such as Pyrex. It goes without saying that the manufacture of preparations with any desired glass transition temperature is known, and all of them are available Cash funds can be used to create glass preparations with j

suitable T values for container and inner glass filling ' S ]

be used. The container glass preparation should have a have a higher melting point than the inner glass preparation including the deposited radioactive solids; ie it should have a higher glass transition temperature and only collapse after the inner glass preparation has sintered. The presence of internal blisters is in many cases intolerable; however, if the absence or reduction of bubbles or foam is desired, | then the T values of the glass preparations should be selected in the manner explained above. I.

If a porous glass filling with a high silica content (> 90 MoI-Ji SiO ₂ ) and a low alkali content j! 25 (<0.5 MoI-Ji Na ₂ O $ ^e Sann ^d ta), Pyrex tubes collapse at to | low temperature to allow sintering of the filling * and (b) Vycor tubes have the following disadvantages: j

The thermal expansion coefficient (1) 1st so low \ he j through the core glass only at very low Belad- dung (e.g. less than 5% by weight for the UK preparations, cf. Example 25) can be compensated;

(2) Due to the high collapse temperature (approx. 1300 to 1400 ^° C.), Cs and other nuclear wastes can volatilize.

While, as shown in the examples, Pyrex and Vycor containers for nuclear waste are suitable for many purposes other preparations have preferred properties. The preferred container is made by a) Fabrication a porous glass container such as a tube according to U.S. Patent 4,110

110 09fc

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Column 10, line 50, to column 16, line 36, and b) from

(Split off) divorce / at least one "dopant", such as cesium, rubidium.

Strontium and copper in a porous glass container. The deposition can be carried out using the following two methods:

1) The preform is converted into one of the ions to be deposited containing solution at a pH between 9 to 13.5, preferably between 10 and 13, immersed for a period of time that of the wall thickness and the desired concentration depends on the funds to be deposited. Usually lying Immersion time between 1 hour and 7 days. The pH of the solution is preferably adjusted with NH ^ OH. For a maximum speed of the ion exchange, the solution is saturated with the ions to be deposited. Habit The materials to be deposited are borrowed as Nitratver bonds immersed in the solution, but chlorides and carbonates can also be used.

2) The porous preform is converted into a connection to be deposited ("dooant")

fertilizer / or a solution of the same immersed. after the

Concentration of the agent to be deposited throughout The preform is uniform, the material is precipitated by lowering the temperature; the preform is in a dated material to be deposited is immersed in free solution, and

; The material to be deposited will partially dissolve and: be allowed to diffuse out of the matrix. Only that near the ! "dopant" precipitated on the outer surface is removed at this stage.

In both of the above-mentioned processes, the porous preform with the separated "dopant" is dried and heated to the collapsed temperature of the pores. The drying should not significantly affect the distribution of the separated "dopant" according to US PS k 110 096 and the shape of the container.

: i5 change. Upon collapse of the pores, the container changes its appearance from translucent to clear without any significant change in shape other than shrinking the linear dimensions by about 20 %. Next is the one to be detached

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Compound used in such an amount that its concentration is between 0.5 to 6 mol-96 in oxide form in the obtained, shrunk glass product is present. The porous glass preform

* Usually contains up to 8 mole-9i B ₃ O ₅ including other components such as clay (if present). Under these conditions, the shrunk container is characterized by a _{minimum SiO 2} content of 86 mol- #. It is preferably by at least about 90 mol- # SiO _? marked

tu draws in order to improve the chemical resistance of the glass.

j Of the two methods mentioned above for introducing the

j "dopants" to be separated into the porous glass will process

1) preferred. In a preform used according to method 1) is the concentration of the "dopant" to be deposited

j the entire cross-section is very uniform, which continues to Γ

j the manufacture of containers using conventional glass blowing processes' allows. In example 27, a glass tube according to the method S ren 1) (ion exchange) produced, heated and attached to a j

End closed without breaking. !

As the preferred container for nuclear waste both one low iscosity (low collapse temperature) and i higher expansion coefficient should j as a glass with 96% SiO _2, is deposited by the addition of alkali Mate-f rials appropriate. It has been found that at concentrations above 85 mol% SiO ₂ and below about 5 mol% alkali, the chemical resistance of Cs or Rb glasses of those of Na or K glass types of comparable composition is superior. At room temperature, sodium glass is be separated off at # 2 mol alkali metal "dopant" 1000 times less stable than cesium glass, and for cesium and rubidium at 100 ⁰ C Rubidiumglas is 10 times better than cesium glass. the chemical resistance for cesium and Rubidiumglasarten was determined by measuring the leaching in water of a pH value of about 5.6 at 20 ⁰ C. The leaching rates have been found to be below 10 " ⁹ g

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Silica per cm of free sample surface per day 20 days of immersion time. This is excellent chemical resistance. Although with one to be severed i> Rubidium- "dopant" get a high chemical resistance a cesium material is preferred because of the much lower cost of cesium. Bivalent elements which are advantageously incorporated together with Cs and / or Rb are Sr and Cu.

When choosing the material to be deposited and its concentration, it is not only the chemical resistance that must be considered but also an adaptation of the thermal expansion coefficient and the container collapse temperature to the sintering temperature of the nuclear waste powder are taken into account. The person skilled in the art can make this adjustment independently Achieve setting of the following variables: composition of the nuclear waste, loading of the same in the nuclear material, Type of "dopant" and its concentration in the container. However, a part of the product can tear, i thereby exposing the core to the external environment. j ι Due to the large surface area of the still j j the core glass covered by the container glass (cladding) there is still a very considerable reduction in leaching velocities of the nuclear waste material in water, j regardless of the cracked shell, making it still j can always be regarded as closed. j

The present invention comprising porous cation exchange particles in a glass container can be used for removal dissolved and undissolved radioactive solids from their highly dilute solutions can be used. E.g.

Solutions with just 1 ppt (parts per trillion)

12 based on the weight of the solution, i.e. 1 part by weight per 10 Parts by weight of solution can be cleaned of radioactive cations !. Dilute solutions with less than 0.01 microcurie radioactivity per ecm and more concentrated solutions, e.g. those with 1 curie or more radioactivity per ecm

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and solutions with radioactivity between 0.01 microcurie and 1 curie per cm3 are also effectively treated in accordance with the invention.

In a typical nuclear reactor there are several sources of radioactive waste (as described above), which in safely removed. These include highly dilute liquid waste streams that are dispersed as well

may contain ω dissolved radioactive solids such as cations, concentrated liquid, radioactive cations, radioactive anions and radioactive solids (such solids! originate from the evaporation of primary, boric acid (which there ■ as a chemical "shim" has been used) containing cooling!

mean and regeneration consumed from evaporation j solutions from regular, commonly used ionic! exchange beds) and / or radioactive gases, such as radioactive krypton and / or iodine. The present invention relates to hence an entire radioactive disposal system Waste in which a finely divided, porous glass or Silica gel with silicon-bonded alkali metal, group! Ib metal and / or ammonium oxy groups in a cation! exchange column is filled, which is preferably a is fusible glass column. The glass or silica gel

i

j 25 particles can be in the column by means of a porous ver;

! Final, like glass wool or a porous disc in the lower-j j ren end and, if necessary, also in the upper end in place | j and held in place. Furthermore, the porous and /, or non-porous glass particles with the ion exchange glass-j or silica gel particles are mixed in the column to obtain i further external surfaces on which j the dispersed, unsettled solids can separate out. The porous glass or silica gel is; preferably finely divided and sieved to a suitable size! the flow rate of the radioactive waste stream i through and between the particles of the porous glass or silica gel to a maximum and the ion exchange time to bring it to a minimum. First the thinned,

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radioactive waste stream passed through the column, and the radioactive cations in the solution are exchanged with the alkali metal, group Ib metal and / or Ammonium cations in porous glass or silica gel for chemical bonding of the radioactive cations to Subjected to glass or silica gel. When the diluted, radioactive waste stream is used as primary coolant again is to be used, the addition of lithium ions as a corrosion inhibitor is expedient. Therefore, the use ι a porous glass or silica gel with silicon-bonded lithiumoxy groups be advantageous, so that j Lithium ions (which do not become radioactive, as does sodium ions) which act as radioactive cations j ib are released to the coolant flow from this

removed. Dispersed, undissolved, J radioactive solids in the dilute radioactive waste stream are mechanically filtered on the porous glass or silica gel particles in the column during the Current percolates through and between the particles. In the ratio of solids in the waste stream to porous glass " or to keep silica gel small enough so that the filter effect is retained when the solids accumulate on the porous glass or silica gel particles, 2b chew fresh, porous glass or silica gel particles are added to the column.

When the ion exchange capacity of the column is exhausted by the dilute, liquid radioactive waste stream, the column can be dried and the concentrated, liquid, radioactive waste (which contains concentrated boric acid, for example at a temperature of 100 ^° C.) of the column

j be added. So the pores of the porous glass or silica gel can with the radioactive, concentrated

j 35 th, radioactive waste containing solids, cations and anions are filled ('stuffed'). Then excess boric acid between the particles of the porous glass or silica gel is ^{washed out with cold water (below 30 0} C), and the particles can be used to separate the

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radioactive solids, cations and anions within the pores of the porous glass or silica gel according to the Method of US PS 4,110,096 are dried. Then kanij the column is first evacuated to remove the decomposition gases; the radioactive gases can enter the glass column introduced and the column can be heated to open the pores of the porous glass or silica gel and then the i Glass column for the purpose of immobilizing and enclosing the '

ίο radioactive cations and solids on the exterior of the porous glass or silica gel particles, the radioactive solids, anions and / or cations in the pores of the ' proous glass or silica gel and the radioactive,! to collapse gases contained in the glass column. The I

is heating can be continued so that the porous glass j or silica gel particles stick to each other and in the ί spaces between them further radioactive solids Γ lock in. After cooling, an extremely long-lasting solid is obtained, which effectively contains the in the glass I column of imported radioactive waste. j

Because some nuclear reactor streams can be basic, appear ^! nen certain elements in radioactive waste as anions, | ζ B. Chromium, molybdenum, praseodymium and cerium ions, the j

? b of course also have to be immobilized. j One way to do this is to use the basic, radio-! active waste stream through a common anion exchanger Resin column to head with a non-radioactive! Base, such as ammonium hydroxide, is regenerated. The discharge!

from this regeneration contains a higher concentration! the radioactive elements and is in a cooker too; a reduced volume of basic, radioactive waste evaporated. Then the concentrated, basic, radio- s active waste at the bottom of the digester under reducing conditions'

Acidified for 3s, and some of the anions, such as Cr, Mo, Ce and Pr, are cations in the above, porous glass column; can be exchanged and removed. The digester bottom material is defined as a concentrated solution or raffinate

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which remains after the solution has evaporated and may contain solids. It can be molecular in the porous Glasses are "stuffed" and become an extremely stable, solid waste product. j

There are also many other industrial wastes which, while not radioactive, are extremely toxic to humans and must be eliminated from waste streams. It is

: to e.g. known that waters in the past r < ; rch mercury, cadmium, thallium, lead, other heavy: <? talle, j

j Insecticides and organic poisons have been polluted.

'Often the concentration of such toxic substances in the : Waste stream very low, creating large volumes of water that;

! i!) contain small amounts of toxic substances, treated; Need to become. Since there are still large numbers of such '

'Pollution could get into the ecosphere, the "

j

ί present invention for cleaning up such waste streams

be applied. ,

The present invention can be used to concentrate and immobilize radioactive cations in glass for extremely long storage times. Thus, for example, the sintered: silicate glass loaded with radioactive solids can correspond to; ι ? chen filled in containers and buried in the ground or in the j

j sea submerged. In addition, the radioactivity of the \ sintered, radioactive solids containing glass production-r

ι j

tes in suitable devices or instruments for

j many different purposes, e.g. in the destruction of \

j 3ü microorganisms, for example in the preservation of food,

ί convey, or during sterilization of sewage sludge or \ j other purposes where radioactivity in constructive

; Way is used, used. !

A typical range for the radioactive solids content I. the glass products obtained according to the invention from the treatment of dilute waste are between about 1 ppb to j 20,000 ppm of the glass product, while glass products j from the treatment of highly concentrated radioactive waste j

030022/0641

up to about 30 weight percent or more, e.g., about 2 to about 30 Wt .-%, can be. Glass products according to the invention that to be used as radioactive sources 5 a solids content falling within the above limits to have.

Usually the glass articles according to the invention comprise ' a first, non-porous glass portion and a non-porous glass portion surrounding the first portion. Of the The first part contains the enclosed and immobilized radioactive materials, while the second part j

ί further, enclosed and immobilized, radioactive i:

j Contains materials. The radioactive materials in one of the fractions are derived from radioactive materials: 'which are soluble in a nuclear waste solution; the radio- ! I active materials in the other part are of such ' ι ι

j, which are insoluble in the nuclear waste solution.

i are. The radioactive materials in the first stake will be '

j '

, 20 derived e.g. from materials in radioactive waste j are insoluble. J

I i

j Furthermore, the radioactive material in the first portion of ^; j materials that are contained in radioactive waste;

j I

125 are soluble. >

I ι

1 i

j In addition, the glass articles according to the invention can have a | j third, non-porous glass component, which is the second:

Part surrounds and is itself free of radioactive materials 3o. The radioactive materials in the < I new glass articles have been described above. Can go further! insoluble, radioactive materials can be metallic precipitates from the oil-satin metal family. The glass objects j de can be rod, ribbon, or any desired '35 configuration. j

030022/0641

In the following examples, unless otherwise stated, all solutions are aqueous solutions. Said "aqueous ammonium hydroxide" or "NH ₄ OH" contains about 28 % NH ₃ ;> ppm means parts per million parts of solution, ppb means parts per trillion (billion) parts of solution; ppt means parts per trillion (trillion) parts Solution; all parts and percentages are on a weight basis. For safety reasons, all simulated: 10 radioactive waste solutions used in the examples were actually non-radioactive;; however, radioactive solutions of the same kind may be used instead and as in the following Examples focused

and be embedded. I example 1

j 15 Manufacture of glass particles and tubes

A. In a platinum crucible at 14OO ° C, a molten glass with a nominal composition of 3.5 mol%: Na ₂ O, 3.5 mol% K ₂ O, was made from sand, boric acid, sodium carbonate and potassium carbonate, 33 MoI-K B ₃ O ₃ and 60 MoI- * SiO ₂ produced. The molten glass was drawn vertically upwards and into rods about 0.8 cm in diameter

i;

j and a length of about 100 cm solidified, which then in .einem , Stainless steel cylinder with a rod also made! stainless steel was crushed. The powder obtained j '25 was sieved and the proportion between 32 and 150 mesh was ί ; selected for use in certain of the following examples; i chooses. !

; ί

ί ί

! B. By pulling the molten glass described above \ ! 30 and application of a slight internal pressure, tubes were produced; those that were closed at one end, ji were formed by releasing the internal pressure during the j i drawing process. Pipes with two open ends were made! j obtained by removing the internal pressure while pulling! 35 and cut off. The tubes had an outside diameter of about 1 cm, a wall thickness of about 0.15 cm and were cut to a length of about 5 cm.

030022/06 * 1

Example 2 Manufacture of porous glass tubes

According to Example 1B, a basic glass tube with one closed and one open end was manufactured and then inserted into heat treated in an electric furnace to induce a suitable phase separation for 110 minutes at 550 ^ C. Thereafter the tubes were tempered by slowly cooling to room temperature and by immersion for 2 days in a 3N HCl solution,

^IU which was saturated with NH-Cl, ^{leached at 95 0} C to form porous tubes. The porous tubes were immersed in hot water for 1 day to wash off residues from the leaching and then kept in a desiccator until the pores were dry from the wash water. The porous j

^1b glass tube had a nominal composition of 95 mol-56 '

SiO ,, 5 mol% B ₇ O, as well as interconnected! Pores and an internal surface area of about 100 m / g. The ,

_ i

The surface of the porous glass tube obtained was marked with »= SiOH; Groups saturated. !

Example 3.;

Production of a porous glass powder I ^

ι According to Example 1A glass rods were produced and before the i

Crushed heat treated 110 minutes at 55O ⁰ C; then were

; 2e> crush them into a glass powder, which is sifted and ■ between 32 and 150 mesh, the proportion going through approx. 6 hours!

j which was ^{leached at about 95 °} C. in a 3N HCl solution. \

The glass powder was about 24 hours at about 25 ⁰ C with de-;

ionized water and then had a nominal 3onelle composition of 95 mol-96 SiO ₃ , 5 mol% B ₉ O _x , it ι had communicating pores and a j inner surface of about 100 m / g. The obtained glass surface j surface was saturated with SiOH groups, and the porous glass!

powder was at about 150 ⁰ C in a beaker on a heating ·

plate dried. j

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Example 4 Use of a porous glass tube to concentrate

and embedding

A dry, porous tube j produced according to Example 2 with one open and one closed end was impregnated with j a solution which simulated a nuclear waste stream j and contained dissolved CsNO and Al ₂ O particles. The 'ceño, solution contained 67 g CsNO, (which may be radioactive): io dissolved in 23 cc of water at 100 ⁰ C and 10 g of Al ₂ O, ale SUS i! suspended solids (which can be contaminated with radioactive isotopes). The inside of the tube was filled with the impregnation solution * and the latter was allowed to penetrate into the pores. A portion of the solution in the tube was allowed to escape through jj ib the tube walls and collected for use in other tubes. This continued until that ^! The inside of the pipe was practically free of solution. _{The Al 2} Oj solids suspended in the solution j *, which are much larger than '! the pore size of the pipe walls were retained inside the pipe. The dissolved CsNO solution also filled the pores of the glass tube walls. Then, the preservation j tene, loaded, porous tube at O ⁰ C was immersed in methanol, \ a failure to effect the in derriiiöften CsNO, in the pores. The inner and outer surfaces of the laden; 2b tubes were ^{immersed in clean methanol at 0} ° C. for 24 hours, the methanol being often changed; thin layers were obtained on the outer and inner pipe surfaces, in which the concentration of precipitated CsNO,

was lower than the concentration of the precipitated CsNO, deeper in the glass. (I.e. the inner and outer surface layers or areas contained about 1/15 of the CsNO, ■ Concentration of those located deeper in the pipe wall j areas.)

3b The porous tube was then removed from the ⁰ ° C. methanol bath and inserted into a practically non-porous, molten silica glass with a larger diameter (3.5 cm) and an open end and at 0 ^° C. under vacuum for 24 hours

dried. Then the fused silica glass tube became * ("dopant solution")

030022/0641

with the loaded porous tube to warm heated / hr up to 625 ⁰ C and left in an oven for slow heating at 15 ° C under vacuum to room temperature. This heating time:> allowed the glass pores to dry further. The loaded porous J-tube inside the non-porous tube was left on for 16 hours 625 ⁰ C to ensure that everything CsNO, decomposes |

ι was, and the nitrogen oxides obtained were emitted and left Cs ₂ O behind. For melting the pores and sintering the

iii glass structure of the porous glass tube was further heated to 875 ⁰ C Vakuunj _r whereby the same in a practically non-J porous glass tube with the enclosed cesium (Cs ₂ O) of the glass structure was converted as ί part. The solid Al ₂ O ₃ remained deposited inside the tube. The pipe was horizontal I placed on a graphite block in a ceramic tube furnace; with another graphite block on top. After heating ^; to about 135O ⁰ C the pipe sags under the weight of the upper one; Graphite block together and causes a fusion and · sealing of the inner pipe surfaces, whereby the Cs ₂ O from the originally dissolved CsNO and the original dispersive ■ alloyed Al ₉ O, solids were immobilized and \ included.

Example 5. ^!

Use of porous powders in non-porous tubes ·;

for embedding "j

A non-radioactive, aqueous solution that consumed a radioactive waste stream from a processing plant was poured into a 50 cc beaker containing 5 g of the porous glass powder produced in Example 3 Simulated nuclear fuel and 3.06 g Fe (NO ₃ J ₃ .9H ₂ O, 1.68 g Ce (NOj) ₃ .6H ₂ O, 0.78 g La (NO ₃ J ₃ -OH ₂ O, 0.78 g CsNO ₃ , 3.88 g Nd (NO ₃ J ₃ .5H ₂ O, 0.52 g Ba (NO ₃ ) ₂ , 2.72 g Zr (NO ₃ J ₄ , 0.42 g Sr (NOj) ₂ , 0.34 g of Y (NO ₃ I _{3 .5H 2} O and 5 ecm of water, with only Zr (NO ₃ I ₄ as precipitate was present. ^{The excess solution was decanted and the beaker was heated to 200 °} C. on a hot plate to dry the glass powder and deposit the dissolved nitrates in the glass powder pores and the undissolved Zr (NO ₃ I ₄ on the outer surfaces of the glass powder. The loaded glass was then

030022 / 06A1

powder in a Vycor tube (Coming 743170-4381) with a nominal composition of 96 % SiO ₂ and 4 % ^B 2 ° 3> an inner diameter of 7 mm, an outer diameter of 9 now and a length of 50 cm. The tube was closed at one end and connected to a vacuum pump. Then the tube containing the porous glass powder loaded in this way was placed in a tube at room temperature under vacuum Open the oven and heat it up to 600 ° C at 15 ° C / hour to remove the remaining water and other volatile matter to evaporate and to decompose the nitrates present into metal oxides and nitrogen oxides and expel the latter »After 24 hours at 600 C the pipe was transferred to a second furnace, which could deliver higher temperatures. After transferring from one furnace to the other, the temperature fell to ι 53O ⁰ C.

j The temperature in the second furnace was gradually ^{increased from 530 to 1340 °} C. over a period of 3 hours and 25 minutes. After 20 j removal of the tube this was above the level of ^Glaspul-: vers collapses, wherein the glass powder with the simulated

■ nuclear waste solution had been impregnated, although the furnace had a relatively large temperature gradient

J pointed and the tube had been inserted too far. Nevertheless, the final product was ά a partially collapsed tube

■ completely enclosed the glass powder without cracks. Not that

j collapsed, lower tube part contained the unimpregnated

Glass that is partly a loose powder, partly into chunks

7 ar and partially melted on the inner walls of the pipe

j30 stuck. There were no cracks in the pipe walls, and one ί Tension of the pipe walls was found under crossed polaroids. The product obtained closed the from the Metal nitrates in the initial simulated nuclear waste stream effectively captured and iso-3alated metal oxides from the environment.

030022/0641

Example 6

Embedding Calcined Nuclear Waste In A Vycor Pipe For Burying

b About 1.5 ecm of a non-radioactive aqueous solution that those described in Example 5, radioactive Waste stream from a spent, simulated nuclear fuel treatment plant was also used in the example 5 given Vycor tube of 50 cm length. The solution contained dissolved nitrates and precipitated Zr (NO,) ^ as in Example 5. No glass powder was added. The tube j was connected to a vacuum pump by a rubber hose. '■ In order to avoid excessive formation of bubbles, the tube was placed in an ice bath at ⁰ ° C. and allowed to dry overnight ί its contents pumped out. The next day the pipe lay.

■ temperature at 28 ⁰ C and the internal pressure at 20 mTorr. That
ι;

Tube was placed in an oven and after being in

; Table 1 given 25th Time
std: min Heating scheme under Vacuum heated. ϊ
20th 12:45 Table 1
Temp. ⁰ C. Pressure; mTorr 13:40 70 137 ί 13:50 80 40 30th 14:05 130 140 14:25 155 50 14:50 190 79 15:15 190 25th 35 3:30 pm 290 50 15:40 340 80 16:05 350 55 17:05 450 34 18:10 COO. 16 20:00 850 16 1340 14th

030022/0641

At 20/00 after 7 hours and 15 minutes of heating, the tube which had collapsed during the heating was removed from the oven. From the data in the table above it can be seen that the '' pressure maxima occurred at 12:45, 13:50 and 14:25, presumably due to the evaporation of water that was still in the tube when it was placed in the furnace; evaporation seemed to occur every time the temperature was increased significantly. If the temperature was kept constant, as at 13:40, 14:05 and 14:50 ^{, the pressure decreased 1} ', since water vapor was removed by the vacuum. Another maximum appeared at 15:30 at around 300 to 400 ^° C., presumably due to the decomposition of the nitrates with the formation of nitrogen oxides.

The end product was a collapsed and locked Vycor- * Tube with the calcined, simulated, nuclear waste (i.e. the oxides Fe, Ce, La, Cs, Nd, Ba, Zr, Sr and Y) embedded inside the collapsed and sealed tube. ■

The surface of the collapsed and sealed tube j showed no cracks and the tube was stress-free when examined under polarized light. The product obtained is suitable for burying or sinking and can be used for such purposes with other, similar products in larger; α containers are packed.

Example £

Use of a non-porous glass powder in a non-porous glass tube for embedding nuclear waste

for the purpose of burying

Pyrex glass (Corning 234030-510) with a nominal composition of 81 % SiO ₂ , 13 % B ₂ O, and 4 % Na ₂ O (by weight) was crushed in a stainless steel cylinder using a stainless steel rod and sifted. The mesh passing between 60 and 150 portion was selected for use overall _{3ί i).} 9.5 g of this Pyrex glass powder were mixed with 0.5 g of porous glass powder impregnated with a simulated nuclear waste stream and dried as in Example 5 ^! net. The mixed powder was placed in a beaker on a j

030022/0641

Hot plate at 11O ⁰ C for about 2 hours further dried. A portion of the mixed powder was then placed in a 50 cm long Pyrex tube of the nominal composition given above and 9 mm outer and 7 mm inner diameter, so that a column about 10 cm high was formed. Next became a piece of platinum wire 1 cm long and 1.5 mm in diameter was added to the powder in the tube. The open pipe end was at i a vacuum pump connected and placed in an oven,!

to where it takes about 4 hours and 35 minutes from about 25 ⁰ C to about; 830 ⁰ C was heated. The finished product showed after out-! take out of the oven some cracks that seemed to lie inside and not extend to the outer surface of the kolla-; biert Pyrex pipe extended. The product obtained j

tb embedded effectively the glass powder A, the simulated radio-active waste materials ι and platinum contained what the group of platinum metals ί represented as Pd, Rh and R, the \ usually in nuclear waste streams dispersed solid I

ι j

fabrics are. The cracking can be prevented by more precisely adjusting the coefficient of thermal expansion of the pipe and its Content to be eliminated. The end product can, preferably! with other similar products in a larger container ι buried in the ground or sunk in the sea.

Example 8

2b Enclosing radioactive vapors in a porous glass rod This example shows that the gas products which escape from the simulated nuclear waste when the same is heated in a glass tube can be captured in a porous glass rod. 6 g of the 'porous' glass powder produced as in Example 3 were placed in a beaker with 2.76 g of CsNO ,, 3.17 g ι! Cu (NO ^) ₂ , 73 ecm H ₂ O and 25 ecm NH ^ OH mixed for 20 1/2 hours {and washed for 24 hours. The impregnated porous glass powder J was dried on a hot plate at a low temperature (about i 200 ^° C. for about 1 hour). Then the sample was in ί a Pyrex glass tube described in Example 9 with a! closed end and a narrowed neck at a distance of about 11 cm from the closed end. The powder formed a 4 cm high column in the tube. A like in

030022/0641

Example 1A produced, 12.5 cm long, porous glass rod j with a diameter slightly over 7 mm was inserted into the tube. The inner end of the rod had been ground to a conical shape (which was then washed in an HF solution to expose the pores), so that a fairly good seal resulted between this end of the rod and the narrowed neck section of the tube. The tube was ^partially:; placed in an upright position in an oven so that the j ίο upper half of the rod was outside the oven. The heating was carried out according to the scheme of time, temperature and pressure given in Table 2. After the heating cycle that became

Tube removed from the furnace; its bottom part was up to 1 cm \ below the conical end of the porous rod kolla-I) s. The state cut of 5 cm, which is halfway

inside and the other half outside of the furnace was slightly yellowed, indicating condensation of copper vapors; indicates, while all other parts of tube and rod practically 'were table colorless. This indicates that the simulated radio-J ₂ O active vapors, ie, copper vapors to escape from the impregnated 'porous glass powder during the heating, captured cm long section of the porous rod in about j ί 5 and were prevented from leaving the tube. The collapsed pipe product obtained embedded the simulated radioactive waste; 2b effectively falls into a strong glass structure. ; Table 2.

Time
std: min Temp. ⁰ C. Pressure;
mTorr 2:30 20th 5 ³ 2:31 95 22nd 2:52 95 17th 3:13 95 13th 3:43 150 13th 4:21 2GO 24 9:30 580 Q 10:20 750 12th

030022/0641

The pressure maximum at 2:31 based on the fact that water is ejected from the ί porous glass powder, and the maximum at 4: 2 "J based on nitric oxide production by decomposition of the j ^b cesium and copper nitrates.!

Example 9 to 13 j

Examples 4 to 8 were carried out using the corresponding,; radioactive nitrates instead of the non-radioactive nitrates listed there, using _{radioactively contaminated 1 AlpO instead of the non-I 1 ″ radioactive Al 3} O ₅ from Example 4. In each case, the radioactive material was immobilized in the resulting glass product and embedded.
Example 14

! 15 A porous glass powder produced according to Example 3 was used 3 days in an approximately 3.2 molar aqueous sodium nitrate /

> Immersed ammonium hydroxide solution and then rinsed in water until the rinse water had a pH of around 8. The powder obtained was then placed in an ion exchange column made of Vycor glass produced according to Example 5. A radioactive primary coolant from a PWN unit using UO ₉ fuel in a stainless steel jacket (containing 4.9% by weight - ^ U) was passed through the column. The primary coolant had the composition given in Table 3, the radionuclide, the possible source, the presumed form and the average concentration being given in microcurie per ecm. The cationic radionuclides are subject to the sodium cations bound to silicon by oxy groups in the porous

30 silica glass powder an ion exchange.

030022/0641

r <o ro

Radionuclide

N / A

Cr

Mn

⁵⁵

Fe

Fe

⁵⁷

⁵⁸

⁶⁰

Co

Go

Co

⁶³ Ni

⁶⁴

Cu

⁸⁹ Sr 90 _Sr

possible source a

Table 5

putative form ^D

average concentr. (MCi / ccm;

(D

U) (D (D

U) U) U) U) (2) (2)

Water, gas

cation

Anion

Cation, s

Cation, ε

Cation, s

Cation, s

Cation, s

Cation, s

Cation, s

Cation, anion, ε cation, cation

χ 10

" ⁵

χ 10 ~ ²

3.3 χ 10
χ 10

-5

" ⁶

3.7 χ 10

2.7 χ IC

-4

" ⁴

1.9 χ IC "" 1.0 χ 10

1.2: <10

" ⁵

" ⁶

4.7 χ ΙΟ " ⁴ 7.7 κ ΙΟ" ⁵ 8.0 χ ΙΟ " ⁶ 5.4 χ ΙΟ" ⁴ 2.8>: IC

" ⁶ χ IC" ⁷

average concentr. (ppb;

2.69 χ

2.18 χ

1.16 7.08 4.02 χ

-6 -8

-8th

-6 -5

7.6 χ

-5

2.03 χ

1.4 2 κ 1θ "

" ⁷

1.48 χ

-5

6.81 χ

" ⁵

-4

-7

1.30 χ

1.41 χ IC

-8 9.93 χ

2.84 χ 1θ " ⁶

cn co fs)

"294 0322]

co I

VO P-

O P- O
i-l P- O
r-i I. X I. X I. X VO co vr O co in co T CN

O
r-l I.
O
r-l VO
I.
O
r-H I.
O P- ι
O
rH X
CN
VO X
VO
rt X
rl
P- r-I
X
in χ;
O
VO CN co UI CN

bO

N +> <D W -P

I O

co cv »

in
I.
O
r-l in
I.
O
H I.
O
r-l X X X P- cn CN r-i rH

r in in Μ I. I. I. Ι O O
H O
r- | σ
r-i O
r-l ί
X 1 X X X » cn j O O vo CN I. - - - - r-l <N VO I.

H Φ

CO

• r-l 4.)

U)

CN

CN

r: ο

U)

U)

U)

U)

r: C. C. C. 1 O O O O I. C. • rH • rl ·. I. -I I. O q C. C. »■ * · ¹ ^ r: t ! I.
I. ί

CN

fN

CN

CN

Vi O * - i CN U Yes O ft « ; J .O Yes O) M. U) CTi σ » ~ z> £ 5 ro CO H M CN -i in m CTl O CN CN r-l ro σ » Ch O CN CN CO Γ0

Γ0

030022/0641

Table 3 continued

O O PO ISJ

134 _Cs

¹³⁶ Cs
¹ ^ ⁷ Cs

14C

3a

141

143

Ce

Ce

144

Ce

143

Pr

110m

13:

'Ag

Kf

182- ..

183

Ta

185

1S7 _W

⁸⁵ kr

(2) (2) (2) (2) (2) (2) (2) (2) (D "(I) ' (D (D (D (D (2) (2)

Cation cation cation cation Anion, s anion, s anion, s anion, s s

S S

S S S

Gas gas

4.7 χ ΙΟ " ⁷
O

1.1 χ ΙΟ " ⁶
4.7 10 ~ ⁶

1.2 χ 10 ~ ⁵
χ 10 ~ ^δ

2.5 χ ΙΟ " ⁵

6.2 χ ΙΟ " ⁵

1.2 χ 10 ~ ⁵

3.7 χ ΙΟ " ⁴

3.62 χ 10

-7

1.26 10 6.45 χ 10

-5

-8th

2 _; 52 χ 10 3.70 χ 10

4.01 χ 10 4.34 χ 10

1.28 χ 10 5.30 χ 10

-6 -7

-6 -7

-6 -7

Table 3 continued

⁸⁸ kr

¹³³ Xe 135γ «

(2) (2) (2)

Gas gas gas

8.9 χ 10 ~ ⁵

4.78 χ χ 10

-5

3.54 χ

-ε -ε

^a (1) Neutron activation products of the nuclides from the fuel jacket, construction material and water

(2) leak from fuel; mostly fission products

Gas: presumably as dissolved gas s: insoluble solids

The radioactive cations of the radionuclides mentioned in Table 3 are subject to the oxy groups on silicon
Bound sodium cations in the porous glass cause a cation exchange and thus bind the radionuclides through the mentioned
j silicon-bonded oxy groups to the porous glass and give

non-radioactive sodium cations from the coolant solution.
; Also the insoluble, radioactive solids in the coolant
1 filter on the outer surfaces of the porous glass particles
'House. Additional porous glass particles can be added to increase the filter capacity of the ion exchange column when the insoluble solids accumulate on the column.

t I

j The anionic radionuclides are not significantly involved in the | ! taColonne removed and run through the same with the coolant .; You can then by treatment with the usual An;

I ion exchange resins are removed. After regeneration \

j!

I of the usual anion exchange resin after its loading j

The regeneration solution containing the anionic radionuclides can be concentrated by evaporation and the
! tene concentrate can by the process of US Pat. No. 4,110,096
j molecularly into the pores of the porous glass in the ion

: The exchange column is "stuffed" after the porous j

j glass to a substantial extent with the silicon-bonded radio;

! 2iiuclid-kationenoxygruppen has been loaded. The loaded j

I porous glass is preferably dried first so that the j

; anionic radionuclide concentrate easily into the porous glass I

ι pores can penetrate. The anionic radionuclide can be obtained by j

i Careful drying process according to US Pat. No. 4,110,096 in I j j

3 (the pores of the porous glass are precipitated or deposited. Then the column containing the porous glass particles can be used to drive off the volatile materials, to decompose the decomposable materials and to drive off the non-radioactive decomposition products as well to collapse
jj ^ ier pores of the particles and sintering them to a uniform mass and also to collapse the Vycor glass column i heated around the sintered mass, whereby the
filtered solids and sintered glass particles that make up the

030022/0641

contain cationic and gnionic radionuclides the collapsed Vycor glass column. Although the glass column cracks due to differential thermal contraction, it still contains the radioactive materials and immobilizes them, and the product formed is many times more permanent than what is currently used cement or metal drums. In this way you get a permanent packaging of concentrated radionuclides, which against No leaching by water or other flowable materials is extremely persistent.

Example 1j5

Using a porous powder in a non-porous tube for embedding

non-radioactive nitrate mixture was used to simulate

of a common United Kingdom UKM-22 waste, the composition of which

uses · I composition is given as oxides in Table 4, / Various j Amounts of nitrate were mixed together in such proportions as to give the approximate oxides given in Table 4

Concentrations received. Corresponding nitrate quantities, the total weight of which corresponded to 2 g of oxides, were put into a | Added 250 cc beaker, 20 cc of H ₂ O were added, the solution was stirred and heated slowly to 80 ⁰ C and at this temperature, formed a light-brown, some unsolved

Solution containing 2 ^ salts. 18 g of a porous glass produced according to Example 3 were added to the solution so that a loading of waste oxides, based on the final glass, of 10 % was obtained. The volume ratio of solution to glass powder was about 1: 1. The mixture was at 90 ⁰ C j

3c dried, then about 3 g of the dry mixture were under vacuum in a Vycor tube described in Example 5 according to \

heated according to the following scheme: j

030022/0641

& Time
hour min T ( ⁰ C) 9.45 , ο ^{10 15} 11.15 25th 11.30 65 11.40 278 is 11.50 342 05/12 383 15.20 403 15.45 520 ²⁰ 16.15 1300 1310 1310

Pressure / m Torr

25 30 26 38 32 68 44 36 16

¹⁶ ί

The finished glass product showed that the pores of the powder j and the granular materials inside the tube were thoroughly J sintered. Next, the tube was completely collapsed; beer, but tore during quenching with air. The finished product was designed to increase its surface area .

I ■

j offers it pulverized and then for different durations at J

I pH 5.6 and 70 ⁰ C subjected to a leach test. The result- I

The results of Table 5 show that the glass sample had an excellent quality

i drew, had chemical resistance. j

030022/0641

oxide

3 Pv) ro - -

\ i tr ο (r c

Tabel

Composition of United Kingdom UKM-22 waste stipulated. simulated. fixed simulated.

oxide

Wt%

Weight?

Al ₂ O ₃ 19.89 19.89 ZrO ₂ 5.57 5.57 Rb ₂ O 0.43 0.43 PO4 0.93 0.93 Cs ₂ O 3.00 3.00 Cr ₂ O ₃ 2.18 2.18 MgO 24.68 24.68 MdO ₃ 6.89 6.89 SrO 1.25 1.25 Fe ₂ O ₃ 10.63 10.63 BaO 1.48 1.48 RuO ₂ 2.65 2.65 Y ₂ O ₃ 0.66 0.66 NiO ₂ '1.40 1.40 La ₂ O ₃ 1.71 1.71 PdO 1.71 1.71 Nd ₂ O ₃ 1.67
7.08 7 _f 08 ZnO
U ₃ O ₈ 1.71
0.23 1.71
replaced
by CeO ₂ CeO ₂ 3.85 3.85 SO4 0.39 0.39

Table 5

chemical resistance of the product obtained in example 15 in deionized water with an initial pH of 5.6 *

b -________ —- ___-—--—-—--—-—--——-—————— —-

Glass component and amount of leach

j sample SiO, Ln Fe Na Cs Sr_

j core and "

; ", Coat (pul- 295 32 <1 <4 <2 <1

ί verified)

: powder core 127 42 n 17 3 8

¹ i

* the data were obtained between days 12 and 15 at 70 ^° C, 71 hrs, j j j

ί ib # * Amount of leaching in ng of dissolved waste per cm of surface area powdered product per day

* ♦ * includes all lanthanides

The in Table 5 and the following Tables 6 and 8 genanni;. _o th Auslaugmengen were by the amount of Toggle normalized \ wesenden component in the glass. Thus they stand for the amount of leaching that the glass would have if the measurement were only on

i would have done this one component. The glass comes off

ι with the amount of silicic acid leach. Sodium, Strontrium and! _; », Cesium diffuse to the surface and are initially leached out with greater speed. Iron and lanthanides; focus on the surface. Gradually it saps

entire glass at the silica speed. j Example 16

J ₃₀ use of porous powder in non-porous tube for i embedding

j A non-radioactive nitrate mixture was prepared similar to i in Example 15 to simulate the UKM-22 waste; to lean. In the preparation of this mixture nitrate _3b were However Zr (NO ^) ^ and K ₂ MoO ^ dissolved separated from the other nitrates with a sufficient amount of concentrated HNO; the other nitrates were dissolved in a 3M HNO solution or in water. Then the two solutions were combined

030022/0641

mixes, with no precipitation being observed. Phoric acid and sulfuric acid were then added to the solution
added to obtain respective amounts of PO, "and SO,". A white, gelatinous precipitate appeared,
did not dissolve upon heating to 7O ⁰ C. About 50 % of the
Nitrates precipitated when the solution was evaporated to about 15 ecm. Then 8 g of the porous glass produced according to Example 3 were added to the solution, which was a
! io loading of 20 % waste oxides, based on the final

Glass revealed. The volume ratio of solution to glass powder
i was about 1: 1. The mixture was about 16 hours at 90 ⁰ C j; dried. About 3 g of the dry mixture was placed under vacuum in a Vycor tube with an outer diameter of i

jib of 13 mm and a wall thickness of 1.5 mm given that!

^ Mixture was stirred at 50 ° C / hr heated to 600 ⁰ C, and after!

j a 48-hour duration at 600 ⁰ C, the tube was a *

i subjected to temperature jump to 1240 ⁰ C, with pores I

! and granular contents of the tube thoroughly sintered. The I

j 20 tube did not collapse, however, and in the waste gas MatriX |

j bubbles formed. During quenching with air S

tore the pipe. Leaching tests were carried out on the sample core, the j

j results given in Table 6 an excellent j

j Show chemical resistance. !

U I

030022/0641

- ft -

Table 6

chemical resistance of the product of Example 16 in deionized water with an initial pH from 5.6 *

Glass component and amount of leaching **

Time
(Days) §122 Fe Ln *** 3.61 N / A 3 S £ <1000 0.34 6 190 1150 737 <2 χ 10 ⁵ G 260 300 1.3 963 ■ 120 344 <2 500 2 340 <300 2.2 550 30th 400 <2 500 2 200 1,400 3.3 370 49 550 <2 500 1 300 120
j 5.7 200 12th <80 <2 500 400 <320 9.3 260 <13 50 <2 500 1 680 150 12.2 220 3 210 500 2 900 <320 15.2 230 <13 56 ... 000

* Data determined at 70 ° C

** Leaching rate in ng of dissolved waste per cm of surface area of pulverized product per day *** includes all lanthanides

Example 17

Use of porous powder in an ion exchange

tube for embedding

As in Example 16, a mixture containing non-radioactive nitrates and porous glass was prepared, but only with an oxide loading of 5%, based on the final glass. About 3 g of the dry mixture were introduced into an ion exchange tube prepared as follows: As in Example 2, an open, porous tube with an outer diameter of 10 ram, a wall thickness of ~ «1 mm and a

TS hours

Length of 20 cm and then / immersed in a solution containing 200 ppm Cs with sufficient NH ^ OH for a pH Contained value of 10; it was then washed at room temperature until a pH of 7 was reached. The Cs exchanged Tube was dried under vacuum and then at

030022 / 06A 1

^{1 night} 11.00 22 15

11.20 180 100

11.25 200 100

15 ° C / h from room temperature to 600 ⁰ C and at? 0 ° C / h
heated from 600 to 870 ^° C. to collapse the pores. then

one end of the pipe was sealed with a flame before j

the mixture of simulated waste and porous glass j

introduced. Then the mixture was under vacuum in tube j

heated according to the following scheme: j

Teup. ; ⁰ C. pressure; mTorr;

¹ 11.35 252 50 i

! .5 1

February 12, 330 43!

i 12.10 470 36 yrs

^! 12.53 547 28 i

¹ !

I 13.00 775 25:

I 13.20 875 24!

I I

I 13.30 927 24 y

i 13.35 1010 24,

i 25 13.47 1075 24 j

t t

j 14.00 1100 24 j

'i

■ The finished glass object showed a complete collage

j beer of the pipe without cracks, but with the granular content ¹

j3o not completely sintered in the tube; here were the warmth j

expansion coefficients of tube and powder adapted. An i

however, full sintering was not achieved because the j

Rohrkollabiertemperatur (about 1100 ⁰ C) was too low for the j waste composition and the loading amount was used.

The composition of the ion exchange tube was 0.5
% By weight of Cs measured.

030022/0641

j Example 18

S Use of a porous powder in a non-porous j tube for embedding

[I "A non-radioactive nitrate mixture was used to simulate a j-West Valley PW-8a drop with the specified I as oxides in Table 7 composition. First j different amounts of nitrate were dissolved separately in 3M HNO or water j and then mixed in such proportions that S κι the respective oxide concentration mentioned in Table 7 er ^; held. A solution with the appropriate amounts of nitrate and! some undissolved salts, the total weight of which corresponded to a total of 4 g [ oxides, were evaporated almost to dryness and; then with 16 g of porous glass (produced according to Example 3) ¹ ib based on a loading with waste oxides of 20 %

final glass, mixed. The mixture was ^{dried at 90 0} C j, about 3 g of the dry mixture were under; Vacuum in a similar Vycor tube as in Example 5 heated to 600 ° C and then subjected to a temperature jump to about 1250 ° C, the mixture of waste and porous j; sem glass completely sintered. The Vycor tube did not completely collapse and ruptured during the air quench. Leaching tests were carried out on the sample core, the results of which, shown in Table 8, indicate excellent chemical resistance.

030022/06 * 1

Table 7 Composition of a West Valley PW-8a waste

specified Oxide wt%

Ma-, O

Fe ₂ O ₃

Cr ₂ O ₃

NOK

P ₂ O ₅

Rb ₂ O

SrO

ZrO ₂

Ag ₂ O
CdO

simul.
Wt%

oxide

specified
Weight %

16 _} 62 34.29

16.62

34.29 1.36 1.74 1.58 0.21 1.25

5.84

7.54

0.36 0.104

0.15

TeO,

0.86

Cs ₂ O 1.14 BaO 1.85 ^Y 2 ° 3 0.05 IxI ₂ O ₃ 6.05 CeO ₂ 12.09 ^Pr 6 ° ll 1.06 Nd ₂ O ₃ 3.62 Sm-O ₃ 0.64 Eu ₂ O ₃ 0.17 Gd-O ₃ 0.43

ε imul. Wt%

1.14 1.85 0.05 6.05 12.09

1.06

3.62 0.64

0.17 0.43

Table 8 j

chemical resistance of the J obtained in Example 18

Product in deionized water with a ί

Initial pH value of 5.6 * j

Glass component and amount of leaching **

Time
(Tafire) SiO? Fe Ln *** Nd Sr Cs J
j
i 0.34 2800 62 <32 6500 560 223 I.
I.
i
! 1.3 905 8th 370 2500 200P <630 ! 2.2 550 25th 440 1400 240 370 ί
I. 3.25 430 12th 440 1360 1200 670 I. 5.7 200 100 150 870 880 340 J 9.3 280 <25 150 780 600 630 12.2 .313 <1 200 780 780 770 • 15.2 300 3 120 840 620 j

ί 20 ♦ data ^{detected at 70 0} C;

; ** Amount of leaching in ng of dissolved waste per cm of surface j

'< area of powdered product per day'

! *** includes all lanthanides

I example Tg j

? b Use of a porous powder in an ion exchange j

^; tube for embedding '

. A waste mixed with the waste described in Example 18, j Porous glass powder was produced in a according to Example 17

I made used pipe. The mixture was j

30 heated to 600 ⁰ C and then ^{subjected to a temperature jump to about 1100 0} C, the mixture of waste and porous in glass completely sintered. The ion exchange tube collapsed completely, but tore during the quenching with air. After examination of the core material it was found that

3b that it is completely sintered and a glass of good quality was. By increasing loading with the waste described in Example 17, the sintering temperature could be below the The temperature of the ion exchange tube can be lowered.

030022/0641

ίο

! 15th

i 25

30th

35

7 "294 532Y

; In the present experiment, however, the amount of waste was too high j and the expansion coefficient was a little too high, which caused j a small number of cracks.

In order to achieve completely sintered products without cracks with the ion exchange tubes used in Examples 17 and 19, an average loading, for example between 8 to | 12 %, can be used.

30022/0641 ORIGINAL INSPECTED

Claims (18)

Claims e
Cy- method of preventing leakage; toxic materials into the environment, characterized in that a mixture of toxic material and glass filling is formed in a hollow "doped" glass container with a high silica content / or this mixture is formed in a first container and then at least part of the mixture is formed in a hollow, "doped" high silica glass container, heats the glass container to collapse its walls and seal it, thereby enclosing and sealing the toxic material in the collapsed, "doped" glass container. is 2. - Method according to claim 1, characterized in that the glass container is a non-radioactive "doped" borosilicate glass container. 3.- The method according to claim 1 and 2, characterized in that the mixture is a solid radioactive material and a Includes glass filling. 4. Method according to claim 1 to 3, characterized in that that the mixture is formed by contacting a flowable material containing the radioactive material with the glass filling is formed. 5.- The method according to claim 4, characterized in that the flowable material is a liquid that is dissolved Contains radioactive material and undissolved radioactive material. 6.- The method according to claim 3 to 5, characterized in that that at least a part of the glass filling comprises porous glass and the radioactive material on and / or in the Glass filling is deposited that the glass container is a non-porous "doped" borosilicate glass container and the The first heating stage is the collapse of the pores of the porous 030022/0641 ORIGINAL INSPECTED Glass and then the collapse of the walls of the borosilicate glass container causes the radioactive material to be trapped in the collapsed borosilicate glass container and is sealed. 7.- The method according to claim 6, characterized in that the amount of contained in the collapsed borosilicate glass container, radioactive material is 1 ppb (part per 10 parts) by weight. 8.- The method according to claim 6 and 7, characterized in that the thermal expansion coefficient of the non-porous, "doped" borosilicate glass container is up to 2 χ 10 is per ⁰ C below that of the glass filling. 9.- The method according to claim 6, characterized in that the glass container is a non-porous, non-radioactive, "doped" borosilicate glass container and the mixture is a flowable material of dissolved, radioactive solids, which are deposited in the pores of the porous glass, and which comprises undissolved, radioactive particles that are on the outer glass surfaces inside the container including the inner wall surface of the container 25 den. 10.- The method according to claim 9, characterized in that the flowable material contains radioactive cations and the porous glass on its surfaces with non-radioactive cations bound to silicon through oxy bonds is formed, wherein the non-radioactive cations can be exchanged for the radioactive cations. 11.- A method according to claim 4, characterized in that the flowable material _l5 is a gas. O30G22 / 064T 12.- The method according to claim 6, characterized in that that the radioactive material comes from a nuclear waste stream is derived. 13 · - Method according to claim 7, characterized in that that the heating stage in the glass container creates such a temperature gradient that an escape of the radioactive Gases is prevented and at the same time the non-radioactive gaseous decomposition products to the atmosphere can be vented. 14, - Glass object comprising a non-porous glass core and a non-porous, non-radioactive, "doped" glass cladding ("clad") enveloping the core, the core being the Contains enclosed and / or immobilized radioactive materials and the jacket has a lower thermal expansion coefficient than that of the core. 15.- Glass object according to claim 14, characterized in that the shell part has a thermal expansion coefficient which is up to about 2 χ 10 "per ⁰ C below that of the core part. 16. Glass object according to claim 14, characterized that the shell part is a non-porous, non-radioactive, "doped" borosilicate glass and the core part is an enclosed therein, Contains radioactive material. 17.- Glass object according to claim 14, characterized in that the shell part is a non-porous, non-radioactive, "doped" borosilicate glass and the core part contains a radioactive material immobilized therein. 18.- Method of varying the coefficient of thermal expansion of a glass container by introducing it and varying a "dopanf" concentration in it 030022 / 06M To make structure suitable for the storage of radioactive, nuclear waste, characterized in that one hollow, porous borosilicate glass container impregnated with a liquid solution of the "dopant", the pH value between 9 and 13.5 and the glass container has an interconnected, porous structure as well = SiOH groups on its surface, whereby the Cation part of the "dopant" with the proton of the = SiOH group is subject to ion exchange, removing the liquid from the glass container and maintaining its porous structure the container shape is collapsed. The patent attorney: 030022/0641