KR100592020B1 - Molybdenum adsorbent for molybdenum-99 / technetium-99m generator and its manufacturing method - Google Patents

Abstract

The present invention relates to a novel molybdenum adsorbent commercially available in a ⁹⁹ Mo / ^99m Tc generator that produces one of the important medical isotopes, technetium-99m (hereinafter referred to as ^99m Tc), and a method for preparing the molybdenum (MoO ₄ ^{2 -)} a sol of a composite material of the adsorbent for adsorbing the silica (SiO ₂₎ and zirconium chloride (ZrCl ₄₎ a composite material, or titanium oxide (TiO ₂₎ and zirconium chloride (ZrCl ₄₎ - synthesized by gel method (sol-Gel Processing) One ⁹⁹ Mo adsorbent is provided, and the adsorbent according to the present invention reacts and adsorbs molybdenum to a zirconium chloride group, thereby providing a molybdenum adsorbent having superior adsorption capacity than a conventional adsorbent and a method of preparing the same.

Molybdenum, Technetium, Adsorbent

Description

Molybdenum adsorbent for molybdenum-99 / technetium-99m generator and its manufacturing method {Adsorbents for molibdenium-99 / technetium-99m generator and preparing process

1 is a graph showing the results of measuring the elution rate of ^99m Tc using a column packed with an adsorbent of Example 1 according to the present invention, a neutral alumina, and an acidic alumina angle 1g at the bottom of the column.

The present invention relates to a novel molybdenum adsorbent commercially available in a ⁹⁹ Mo / ^99m Tc generator, which produces one of the important medical isotopes, technetium-99m (hereinafter referred to as ^99m Tc), and more specifically, to a method of preparing molybdenum ( The adsorbent adsorbing MoO ₄ ^2- ) is composed of silica (SiO ₂ ) and zirconium chloride (ZrCl ₄ ) composite or titanium oxide (TiO ₂ ) and zirconium chloride (ZrCl ₄ ) composite. The present invention relates to a molybdenum adsorbent having a superior adsorption capacity than a conventional adsorbent because the compound is reacted and adsorbed to a zirconium chloride group by synthesizing with molybdenum).

^99m Tc is one of the most important medical isotopes and is used in various medical diagnostic areas. In other words, ^99m Tc is a gamma ray emitter with a half-life of 6 hours, and radionuclides are used for various medical diagnosis of intractable diseases such as cancer and heart disease, and thus 80% of the global demand for medical isotopes worldwide. The above is for ^99m Tc and the demand is expected to increase continuously.

This technetium-99m is generated as a radionuclide of molybdenum-99 ( ⁹⁹ Mo) produced by the neutron emission or cleavage product of molybdenum-98 ( ⁹⁸ Mo). ^99m Tc can be continuously separated from the parent-child mixture by solvent extraction or chromatography techniques. Chromatographic methods are more popular than other methods because of the smaller size, ease of operation and less time constraints of the apparatus. However, this method also has the disadvantages of using neutron-irradiated natural molybdenum as a raw material, such as limitation of movement and cumbersome process as the device is enlarged. The use of ⁹⁹ Mo extracted from the fission product in this chromatographic method can overcome the above problem since cleavage ⁹⁹ Mo does not contain other inert molybdenum isotopes. This type of chromatography ^99m Tc extraction system is called the “ ⁹⁹ Mo / ^99m Tc generator”, and its convenience and portability make it possible to extract ^99m Tc in hospitals, making it popular worldwide in nuclear medicine.

Many ^99m Tc generator for using the ⁹⁹ Mo produced by the fission of highly enriched U-235, this fission ⁹⁹ Mo are extremely with a high specific activity (specific activity), also many Ci (Curie) amount of ⁹⁹ currently in use Mo can be adsorbed onto very small aluminum columns (1 to 1.5 g of aluminum), which can be effectively eluted with only small volumes (less than 2 to 5 ml) of eluent to obtain high concentrations of ^{99 m} Tc (greater than ^{99 m} Tc 1Ci). The nuclear fission of U-235, however, creates a large amount of gaseous and solid radioactive materials of many elements, which leads to cumbersome and expensive waste disposal problems.

There are many methods for extracting ⁹⁹ Mo from various materials irradiated in a reactor, and US Pat. No. 5,910,971 describes a method and apparatus for generating ⁹⁹ Mo in uranil sulfate fuel in a homogeneous reactor. Fuel containing ⁹⁹ Mo is pumped through the sorbent to extract the organic Mo ⁹⁹ in a closed cycle system. U.S. Patent 5,962,597 describes certain organic adsorbents for extracting ⁹⁹ Mo from solution reactors disclosed in U.S. Patent 5,910,971.

In addition, Korean Patent Application No. 2002-7007625 describes an inorganic adsorbent which effectively and selectively extracts ⁹⁹ Mo from a radioactive solution of uranium, which has a high radiation resistance allowing use in the high radiation zone of the reactor. In addition, many ⁹⁹ Mo extraction cycles facilitate the closed-cycle extraction method to maintain nuclear fuel uranium concentrations while minimizing radioactive waste disposal problems.

U.S. Patent 4,280,053 also discloses a ^99m Tc generator containing zirconium molybdate (ZrOMoO ₄ ) gels produced from ⁹⁹ Mo. Wherein the gel is prepared by dissolving ⁹⁹ Mo in a rather excess aqueous ammonia solution or sodium hydroxide solution. The pH is adjusted to between 1.5 and 7 by addition of acid, and the resulting solution is added to a stirred aqueous solution of zirconium to form a molybdate precipitate, which is collected by filtration or liquid distillation and then dried in air and used in a generator. Grind to size to obtain zirconium molybdate.

However, the above-described method for preparing zirconium molybdate gel must adjust the pH after the acidic slurry is formed, and the slurry must be filtered and washed to crush and dry the dried precipitate to the desired particle size. Commercial production of highly radioactive zirconium molybdate gels through these various and numerous steps is technically difficult and undesirable.

On the other hand, despite the possibility of generating ⁹⁹ Mo by the neutron impact of the ⁹⁸ Mo target in the natural state, such a reaction generates ⁹⁹ Mo with low inactivity, and a generator that generates ⁹⁹ Mo with such low inactivity is inevitable. To increase the volume of the larger column, eluent. Thus, the resulting ^99m Tc solution will contain low concentrations of ^99m Tc in a large volume, which is undesirable.

The international supply of nuclear fission ⁹⁹ Mo is now largely dependent on Canada, so there is a need to develop alternative technologies for technetium generators that use neutron-emitting ⁹⁹ Mo as a raw material to avoid stable supply and long distance transport. Recently, a generator system using a high capacity adsorbent for molybdenum salts has been presented by Kaken Co., Japan. This generator system uses zirconium polymer (PZC) as the adsorbent and reacter-spun molybdenum (ie low inertness) as the ^99m Tc source. However, this material has the disadvantage of exhibiting undesirable molybdenum loading conditions and poor column operation such as exotherm during molybdenum loading.

Therefore, in the present invention, a study to develop an adsorbent having superior physical properties and high adsorption capacity was carried out using sol-gel technology, in which silica-zirconyl chloride and titania-zirconyl chloride were applied to molybdenum. The present invention has been completed by discovering that it can be used as a high performance adsorbent.

It is an object of the present invention to provide an adsorbent capable of adsorbing molybdenum with high adsorption capacity in a ⁹⁹ Mo / ^99m Tc generator and a method of manufacturing the same.

Furthermore, the present invention provides a technetium generator which provides a ⁹⁹ Mo adsorbent to produce an adsorption tube adsorbing ⁹⁹ Mo, which is a radioisotope, and extracts ^{99 m} Tc.

The present invention for achieving the above object provides a ⁹⁹ Mo adsorbent using either zirconium chloride as the functional group of the ⁹⁹ Mo adsorbent and silica or titania as a structural skeleton.

The present invention also provides a method for producing a ⁹⁹ Mo adsorbent using either zirconium chloride as the functional group of the ⁹⁹ Mo adsorbent and silica or titania as the structural skeleton.

The adsorbent of the present invention as described above adsorbs molybdate on zirconium chloride as follows.

Hereinafter, the present invention will be described in more detail.

The adsorbent of the present invention is provided in the form of a silica-zirconium chloride (SiO ₂ -ZrCl ₄ ) composite.

The adsorbent of the present invention described above is in the form of a silica-zirconium chloride (SiO ₂ -ZrCl ₄ ) composite;

Preparing a silicic acid solution using hydrolysis and polymerization of tetraethoxysilane (TEOS) (step 1);

Preparing a zirconium mixture by using hydrolysis and polymerization of zirconium chloride (step 2); And

It is prepared by the sol-gel method of forming a gel in a mixed solution of the solution prepared in step 1 and step 2.

In step 1 according to the present invention using the hydrolysis and polymerization of tetraethoxysilane to prepare a silicic acid solution of solution 1-1 and solution 1-2 as follows.

<Production of Solution 1-1>

1) 1 mol of TEOS is dissolved in 2 to 8 mol of ethanol.

2) Add 2 moles of water containing 0.001 to 0.1 mol of hydrochloric acid to the solution of 1) and stir for 15 minutes to 48 hours.

<Preparation of solution 1-2>

1) 1 mol of TEOS is dissolved while stirring a mixture of ethanol and toluene. The quantity of ethanol and toluene is 2-8 mol, respectively, Preferably it is 3-5 mol.

2) To the solution of 1), 2 moles of water containing 0.001 to 0.1 mol of hydrochloric acid are stirred for 15 minutes to 48 hours.

In step 2, a zirconium mixture of solutions 2-1, 2-2, 2-3, and 2-4 is prepared by using hydrolysis and polymerization of zirconium chloride.

<Production of Solution 2-1>

1) Evenly disperse zirconium chloride powder in chloroform. The amount of chloroform is 0.5 to 5 times the zirconium chloride weight ratio, and zirconium chloride is 0.5 to 2.0 times the molar amount of TEOS.

2) Slowly add the isopropanol while stirring the dispersion of 1) and continue stirring for 15 to 60 minutes. The amount of isopropanol is to be 2 to 4 times the molar amount of zirconium chloride.

<Production of Solution 2-2>

1) Evenly disperse zirconium chloride powder in chloroform. The amount of chloroform is 0.5 to 5 times the zirconium chloride weight ratio, and zirconium chloride is 0.5 to 2.0 times the molar amount of TEOS.

2) Slowly add 2-methoxy-1-ethanol while stirring the dispersion of 1) and continue stirring for 15 to 60 minutes. The amount of ethylene glycol is 0.05 to 1.0 times the molar amount of zirconium chloride.

<Preparation of solution 2-3>

1) Evenly disperse zirconium chloride powder in chloroform. The amount of chloroform is 0.5 to 5 times the zirconium chloride weight ratio, and zirconium chloride is 0.5 to 2.0 times the molar amount of TEOS.

2) Slowly add acetylacetone while stirring the dispersion of 1) and continue stirring for 15 to 60 minutes. The amount of acetylacetone is 0.05 to 1.0 times the molar amount of zirconium chloride.

<Production of Solution 2-4>

1) Evenly disperse zirconium chloride powder in chloroform. The amount of chloroform is 0.5 to 5 times the zirconium chloride weight ratio, and zirconium chloride is 0.5 to 2.0 times the molar amount of TEOS.

2) Add acetone (acetone) slowly while stirring the dispersion of 1) and continue stirring for 15 to 60 minutes. The amount of acetone is 0.05 to 1.0 times the molar amount of zirconium chloride.

Finally, in step 3, a gel is formed in the mixed solution in which each solution prepared in steps 1 and 2 is mixed as follows.

1) Slowly add one of the 1-1, 1-2 solutions prepared in step 1 to one of the 2-1, 2-2, 2-3, 2-4 solutions prepared in step 2 with vigorous stirring.

2) Slowly add the triethyleneamine (TEA) solution while stirring the solution of 1). The amount of triethyleneamine is 0-100 times the molar ratio added hydrochloric acid.

3) The solution of 2) is stored at room temperature for 12 hours to 72 hours, and dried in an oven at 50-200 ° C. for 12 hours to 72 hours to obtain a gel.

4) Grind the dried gel using a mortar and pestle to obtain 75-320 μm particles using a sieve.

The adsorbent particles according to the invention obtained as described above can be stored in sealed bottles for long use.

In addition, the adsorbent of the present invention is provided in the form of a titanium oxide-zirconium chloride (TiO ₂ -ZrCl ₄ ) composite.

The adsorbent of the present invention described above is in the form of a titanium oxide-zirconium chloride (TiO ₂ -ZrCl ₄ ) composite;

Preparing a titanium oxide solution using hydrolysis and polymerization of titanium butoxide (TiOBu) (step 1);

Preparing a zirconium solution using hydrolysis and polymerization of zirconium chloride (step 2); And

It is prepared by the sol-gel method comprising the step of forming a gel in a mixed solution of the solution prepared in step 1 and step 2.

In step 1, a titanium oxide solution is prepared by using hydrolysis and polymerization of titanium butoxide (TiOBu) as follows.

Of titanium oxide solution Manufacture

1) It melt | dissolves in 2-6 mol isopropanol, stirring 1 mol TiOBu.

2) 2 to 6 mol of 90 to 99.9% acetic acid is added to the solution of 1) with stirring and reacted for about 15 to 60 minutes.

In step 2, a zirconium solution is prepared by using hydrolysis and polymerization of zirconium chloride.

<Production of Zirconium Solution>

1) Evenly disperse zirconium chloride powder in chloroform. The amount of chloroform is 0.5 to 5 times the weight ratio of zirconium chloride, and zirconium chloride is 0.5 to 2.0 times the molar amount of TiOBu.

2) Slowly add isopropanol while stirring the dispersion of 1) above and continue stirring for 15 to 60 minutes. The amount of isopropanol added is 1 to 4 times the molar amount of zirconium chloride.

In step 3, the solution prepared according to step 1 and step 2 is mixed as follows to gel to prepare a solid.

1) The solution prepared in step 1 is slowly added to the solution prepared in step 2 with vigorous stirring.

2) Slowly add distilled water while stirring the mixed solution prepared in 1). The amount of distilled water is 0.55 to 10 times the molar amount of the added zirconium chloride and TiOBu.

3) The mixed solution from 2) is gelled by storing at room temperature for 12 hours to 72 hours, and oven dried at 80 ° C. for 24 hours to 72 hours to obtain a solid.

4) The obtained solid is pulverized using a mortar and pestle to obtain particles of 75 to 320 μm using a sieve.

The adsorbent particles according to the invention obtained as described above can be stored in sealed bottles for long use.

The molybdenum adsorbent consisting of the silica-zirconium chloride (SiO ₂ -ZrCl ₄ ) composite and the titanium oxide-zirconium chloride (TiO ₂ -ZrCl ₄ ) composite of the present invention prepared as described above is more effective than the conventional adsorbents commonly used in technetium generators. Superior in ability

In addition, the adsorbent according to the present invention can be used for the generator of ¹⁸⁸ W / ¹⁸⁸ Re exhibiting a chemically similar reaction in addition to the generator for ⁹⁹ Mo / ^99m Tc. This is typically ⁹⁹ Mo / ^99m generator for Tc is appointed adsorbent ¹⁸⁸ W / ¹⁸⁸ Re occurs can be used as the appointed adsorbent is a well-known fact in the art and in fact commercially available ⁹⁹ Mo / ^99m generated appointed adsorbent alumina for Tc is ¹⁸⁸ W / ¹⁸⁸ Re is used as an adsorbent for generators.

Hereinafter, the present invention will be described in detail with reference to Examples, but the scope of the present invention is not limited thereto.

<Example 1>

Synthesis of Silica-Zirconium Chloride (SiO ₂ -ZrCl ₄ ) Composite 1

After dissolving 4.62 ml of TEOS in 4.69 ml of ethyl alcohol and 8.56 ml of toluene mixture, 0.72 ml of 0.028 mol / L HCl solution was added with stirring, followed by reaction for 180 minutes. In another vessel, 4.68 g of ZrCl ₄ was dispersed in 5 ml of chloroform, and then 2.42 g of isopropanol was added during stirring and reacted for about 15 minutes. The reacted TEOS solution was slowly added to the reacted ZrCl ₄ solution, followed by addition of 0.14 ml of triethylamine (TEA), followed by standing at room temperature for 24 hours and drying at 80 ° C. for 48 hours. Powder was prepared using a mortar and pestle and then sealed.

<Example 2>

Synthesis of Silica-Zirconium Chloride (SiO ₂ -ZrCl ₄ ) Composite 2

3.24 ml of TEOS was dissolved in 3.50 ml of ethyl alcohol in a container, and then 1.08 ml of 0.1 mol / L HCl solution was added while stirring, followed by reaction for 24 hours. In another vessel, 3.50 g of ZrCl ₄ was dispersed in 5 ml of chloroform, and 0.55 ml of 2-methoxy-1-ethanol was added while stirring, followed by reacting for about 3 hours. The reacted TEOS solution was slowly added to the reacted ZrCl ₄ solution, then left at room temperature for 24 hours and dried at 80 ° C. for 48 hours. Powder was prepared using a mortar and pestle and then sealed.

<Example 3>

Synthesis of Silica-Zirconium Chloride (SiO ₂ -ZrCl ₄ ) Composite 3

3.24 ml of TEOS was dissolved in 3.50 ml of ethyl alcohol in a container, and then 1.08 ml of 0.1 mol / L HCl solution was added while stirring, followed by reaction for 24 hours. In another vessel, 3.50 g of ZrCl ₄ was dispersed in 5 ml of chloroform, followed by addition of 1.55 ml of 2,4-pentanedione while stirring for about 3 hours. The reacted TEOS solution was slowly added to the reacted ZrCl ₄ solution, then left at room temperature for 24 hours and dried at 80 ° C. for 48 hours. Powder was prepared using a mortar and pestle and then sealed.

<Example 4>

Synthesis of Titanium Oxide-Zirconium Chloride (SiO ₂ -ZrCl ₄ ) Composite 1

After dissolving 5.02 ml of TiOBu in a mixture of 2.43 ml of isopropanol and 2.83 ml of 96% acetic acid, the reaction mixture was allowed to react for 30 minutes. In another vessel, 3.73 g of ZrCl ₄ was dispersed in 5 ml of chloroform, and then 2.43 ml of isopropanol was added during stirring, followed by reaction for about 15 minutes. After slowly adding the reacted TiOBu solution to the reacted ZrCl ₄ solution and reacting for 15 minutes, 2.30 ml of distilled water was added slowly. This solution was left at room temperature for 24 hours and dried at 80 ° C. for 48 hours. Powder was prepared using a mortar and pestle and then sealed.

Example 5

Synthesis of Titanium Oxide-Zirconium Chloride (SiO ₂ -ZrCl ₄ ) Composite 2

In a vessel, 5.02 ml of TiOBu was dissolved in a mixture of 2.00 ml of isopropanol and 4.72 ml of 96% acetic acid, followed by reaction for 30 minutes. In another vessel, 3.73 g of ZrCl ₄ was dispersed in 5 ml of chloroform, and then 2.87 ml of isopropanol was added during stirring and reacted for about 15 minutes. The reacted TiOBr solution was slowly added to the reacted ZrCl ₄ solution. This solution was left at room temperature for 24 hours and dried at 80 ° C. for 48 hours. Powder was prepared using a mortar and pestle and then sealed.

Experimental Example 1

Mo adsorption amount measurement

In order to determine the adsorption capacity of molybdate (MoO ₄ ^2- ) of the adsorbent prepared according to the embodiment of the present invention, the following experiment was performed.

0.5 g of each adsorbent prepared according to each of the above examples and alumina used as a conventional adsorbent, respectively, molybdenum (Mo) 10,000 mg / L, sodium ion (Na ⁺ ) 5,520 mg / L, chlorine ion (Cl ⁻ ) 4,570 mg / The solution was added to 25 ml of a solution having a pH of 7 and stirred at room temperature for 3 hours to measure a change in the amount of molybdenum in the aqueous solution. The solution was added with a radio tracer, ⁹⁹ Mo, to the concentration of 0.3 uCi / ml before reacting with the adsorbent. The adsorption amount of molybdenum was calculated by measuring the change in the amount of radioactivity of the aqueous solution, and the results are shown in Table 1 below.

division Molybdenum adsorption amount (mg / g), pH ~ 7 Example 1 214 Example 2 246 Example 3 173 Example 4 269 Example 5 268 Acid alumina <5

Experimental Example 2

Elution rate measurement of ^99m Tc

In order to determine the elution rate of ^99m Tc from the ⁹⁹ Mo / ^99m Tc generator equipped with a column using the adsorbent prepared according to the embodiment of the present invention and alumina as a conventional adsorbent, neutral alumina, acidic alumina and Example 1 The elution rate of ^{99 m} Tc was measured using the column which packed each 1 g of the adsorbents at the bottom of the column, and the result was shown in FIG . As shown in FIG. 1 , the elution rate of ^99m Tc varied from 60 to 93%, but it can be seen that the use of the adsorbent of Example 1 is almost constant at about 85% for 6 days.

The molybdenum adsorbent for the ⁹⁹ Mo / ^99m Tc generator of the present invention configured as described above is composed of a silica-zirconium chloride (SiO ₂ -ZrCl ₄ ) composite and a titanium oxide-zirconium chloride (TiO ₂ -ZrCl ₄ ) composite. Molybdenum adsorption capacity is superior to that of conventional adsorbents, and a method for easily preparing such adsorbents is provided.

Claims (15)

delete delete delete Tetraethoxysilane (TEOS) is dissolved in ethanol, and the solution is added with water containing 0.001 to 0.1 mol of hydrochloric acid, followed by stirring for 15 minutes to 48 hours to hydrolyze and polymerize the tetraethoxysilane. To prepare a silicic acid solution (step 1); Preparing a zirconium mixture by using hydrolysis and polymerization of zirconium chloride (step 2); And Method of producing a ⁹⁹ Mo adsorbent, characterized in that consisting of a step (step 3) to form a gel in the mixed solution of the solution prepared in step 1 and step 2. After dissolving the tetraethoxysilane (TEOS) while stirring the ethanol and toluene mixture, the solution was hydrolyzed and polymerized by stirring water containing 0.001 to 0.1 mol of hydrochloric acid for 15 minutes to 48 hours. Reacting to prepare a silicic acid solution (step 1); Preparing a zirconium solution using hydrolysis and polymerization of zirconium chloride (step 2); And Method of producing a ⁹⁹ Mo adsorbent, characterized in that consisting of a step (step 3) to form a gel in the mixed solution of the solution prepared in step 1 and step 2. delete delete delete The method of claim 4 or 5, wherein the zirconium mixture of step 2 is dispersed in the zirconium chloride powder in chloroform of 0.5 to 5 times the weight ratio of the zirconium chloride, and then stirring the dispersion to 0.05 to 1.0 times the molar amount of zirconium chloride. Method of producing a ⁹⁹ Mo adsorbent, characterized in that is prepared by continuously stirring for 15 to 60 minutes after the addition of 2-methoxy-1-ethanol. The method of claim 4 or 5, wherein the zirconium mixture of step 2 is dispersed in the zirconium chloride powder in chloroform of 0.5 to 5 times the weight ratio of the zirconium chloride, and then stirring the dispersion to 0.05 to 1.0 times the molar amount of zirconium chloride. Method of producing a ⁹⁹ Mo adsorbent, characterized in that the prepared by continuously stirring for 15 minutes to 60 minutes after the addition of acetylacetone (acetylacetone). The method of claim 4 or 5, wherein the zirconium mixture of step 2 is dispersed in the zirconium chloride powder in chloroform of 0.5 to 5 times the weight ratio of the zirconium chloride, and then stirring the dispersion 0.05 to 1.0 times the molar amount of zirconium chloride Method of preparing a ⁹⁹ Mo adsorbent, characterized in that the acetone (acetone) after the addition of 15 minutes to 60 minutes to continue stirring. The method according to claim 4 or 5, wherein the gel formation of step 3 is added to the solution prepared in step 1 with stirring, and then stirring the solution triethyleneamine (TEA) After the solution was added and stored for 12 hours at 72 hours at room temperature, and dried in an oven for 12 hours at 72 hours at 50-200 ℃ obtained method of ⁹⁹ Mo adsorbent. delete delete delete

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