EP0823855A1

EP0823855A1 - Catalytic-hydrothermal disposal process of chemical military materials

Info

Publication number: EP0823855A1
Application number: EP95919406A
Authority: EP
Inventors: Hartmut Hederer; Natarajan Thiagarajan; Kjeld Andersen
Original assignee: Krupp Uhde GmbH
Current assignee: ThyssenKrupp Industrial Solutions AG
Priority date: 1995-05-05
Filing date: 1995-05-05
Publication date: 1998-02-18
Also published as: WO1996034662A1

Abstract

The chemical military materials include both the group of chemical agents used in chemical weapons and the group of fuels used in military aircraft. Chemical military materials must be disposed of at the end of their storage life. A continuous process is disclosed for that purpose. The chemical military materials are first suspended and/or dissolved in water and an alkaline catalyst is added to the aqueous mixture. A reaction mixture is thus obtained. The reaction mixture is brought to the reaction pressure by liquid feeding means, for example a high pressure pump. The reaction pressure lies between 100 bars and 1000 bars. The reaction mixture is heated up to a reaction temperature lower than the critical temperature of pure water. The usual reaction temperature is 350 DEG C. The reaction mixture heated up to the reaction temperature then flows over a catalyst bed that contains a catalytic zirconium dioxide. The catalysed reactions produce a hot mixture of converted materials that is substantially free of chemical military materials. The hot mixture of converted materials is cooled down and expanded in a separator, producing a gaseous phase with CO2, CH4 and H2, an oily phase and an aqueous phase with dissolved salts that may all be dumped.

Description

Process for the catalytic-hydrothermal disposal of chemical weapons

The present invention is directed to a method for the disposal of chemical weapons in a continuously operated process.

Gun chemical substances are produced in a wide variety of ways and in large quantities and are stored for future military-technical uses.

These chemical weapons include both the group of chemical warfare agents that can be used as chemical weapons and the group of fuels used in military aircraft.

If these substances are not used in the intended combat use, they already represent a considerable danger potential due to their existence accumulated in the stores, the safe control of which becomes increasingly problematic with increasing storage time.

For this reason, those authorized to dispose of these chemical weapons endeavor to dispose of their supplies. On the one hand, they have entered into agreements on arms limitation, on the other hand, the stocks are subject to specific corrosion and aging processes which make the handling of weapons increasingly dangerous for the users themselves, and technical progress also makes the weapon systems kept obsolete.

Chemical warfare agents are usually disposed of in special incineration plants. High demands are placed on the degree of implementation of the combustion reactions. The proportion of the warfare agents not to be destroyed during the combustion should be within the range of the technical detection limit, that is, 99.999999% the amount of warfare agent introduced into the combustion must be brought to reaction.

These requirements are met by using high flame temperatures and / or high residence times. Flame temperatures of 2000 ° C to 2600 ° C must be generated. The apparatuses suitable for this purpose are fed with hydrogen and oxygen as fuel gas, and their operation is expensive and prone to danger.

The flue gases created by the combustion themselves also carry environmentally hazardous substances. Because a large number of chemical warfare agents contain halogenated compounds, dioxins and / or furans, for example, form in the flue gases when they cool down.

When burning z. B. solid rocket fuels form nitrogen oxides, which on the one hand break down the ozone layer and on the other hand increase the greenhouse gas effect. The combustion of these rocket fuels thus results in damage to the environment.

In order to avoid environmental damage from such incineration plants, the plants are equipped with downstream flue gas cleaning stages. The disposal of the pollutants accumulating in the cleaning stages causes further problems, the operators of the incineration plants would generally prefer to see their occurrence avoided.

Under the now prevailing conditions of the exacerbated ecological situation, the disposal of the chemical warfare agents has to be carried out by means of processes in which only absolutely harmless residues are produced for humans and the environment. The chemical warfare agents to be disposed of in the arsenals and production facilities mainly consist of mixtures of various chemical compounds which are formulated for use in accordance with the tactical tasks of war weapons.

The chemical compounds known for their toxic effects on humans and used in chemical weapons are described in the publications [1] and [2].

With the method of the present invention, the chemical warfare agents present as mixtures, including the toxic active substances occurring in them, are converted into harmless residues. Because of the multitude of possible mixture combinations, the enumeration of the formulations used, some of which are the subject of military efforts to maintain confidentiality, would give both a confusing and incomplete description of the disposal problem.

For this reason, the toxic agents are named below as representative of the chemical warfare agent mixtures essentially formulated from them, which are converted into harmless residues by the process of the present invention.

Warfare agents for military exercises contain eye irritants. Halogenated, aliphatic eye irritants such as dichloromethyl ether, monobromazetone, monochloroacetone, monobromomethyl ethyl ketone, ethyl bromoacetate and perchloromethyl mercaptan are known.

Other eye irritants are the halogen cyanines such as fluorocyanine, chlorocyanine, bromocyanine, iodocyanine.

Another group of eye irritants is given by the halogenated, aromatic eye irritants such as:

Benzyl chloride,

Benzyl bromide, ortho-nitrobenzyl chloride, xylyl bromide,

Chloroacetone phenone (CN substance), phenylcarbylamine chloride, ortho-chlorobenzylidene malodinitrile, perlargonic acid morphine, dibenz-1,4-oxazepine.

Phosgene and its related compounds diphosgene, triphosgene and chloropicrin are mentioned as warfare agents with a predominantly lung-damaging effect.

Organic arsenic and organic lead compounds are considered nasal and throat irritants. The following are mentioned:

Diphenylarsine chloride,

Diphenylarsine cyanide,

Phenarsazine chloride (adamsite).

The aliphatic arsenic compounds methylarsine dichloride, ethylarsine dichloride and 2-chlorovinylarsine dichloride (Lewisite) are listed as skin-damaging warfare agents.

Among the organic sulfur compounds that have a toxic effect on the skin and metabolism are so-called mustards

Dichlorodiethyl sulfide (sulfur mustard),

Difluorodiethyl sulfide (fluorine mustard),

Dibromo diethyl sulfide (bromine lost),

Diiodoethyl sulfide (iodine mustard) has become known.

Toxic aliphatic amines are referred to as nitrogen mustards, the following compounds are most frequently described:

Dichlorodiethylamine,

Trichlorotriethylamine,

Methyl (dichlorodiethyl) amine. Halogenated oximes act as skin-damaging nettles, the following are essentially mentioned:

Monochloroformoxime,

Dichloroformoxime (phosgene oxime),

Trichloromethylchloroformoxime.

Toxic aliphatic fluorocarbon compounds are considered to be so-called blood and nerve toxins, of which the following are described:

Fluoroacetic acid,

Sodium fluoroacetate,

Methyl fluoroacetate,

Fluoroacetic acid-2fluoroethyl ester,

Fluoroethyl alcohol.

Toxic organic phosphorus derivatives are named after phosphoric acid or after phosphonic acid:

Tetraethyl pyrophosphoric acid ester (TEPP),

Diethyl p-nitrophenyl phosphoric acid ester (paraoxon,

E 600),

Diisopropyl fluorophosphoric acid ester (DFP),

Dimethylaminozyanphosphorsäureethylester (Tabun),

Isopropyl methyl fluorophosphonate (sarin),

Pinacolyl methyl fluorophosphonate (Soman),

Methyl fluorophosphonic acid choline ester (TAMMELIN ester or

V fabrics).

The military codes VM, VX, VE, VS, VG have become known from the USA of the TAMMELIN esters, where VX stands for methylphosphonic acid orthoethyl (diisopropyl) aminoethyl thiol ester. In addition to the toxic agents listed above, there are other chemically related compounds that are reported in detail in [2].

For the purpose of their intended use in combat use, the toxic active ingredients are partially combined with one another and / or mixed with other auxiliaries in order to produce the actual combat substance formulations.

The added auxiliaries can e.g. B. be polymeric materials that give the warfare agents a pasty consistency or, for example, surfactants, halogenated hydrocarbons, cyclic ethers, alcohols, dimethyl sulfoxide, diethyl formamide to adapt the warfare agents to the tactical objective. Dicyclohexylcarbodiimide is added to the VX as a stabilizer, which increases the shelf life of VX.

Because the incineration of such complex chemical warfare agents creates environmentally harmful residues, other methods of disposal of the chemical warfare agents are also followed.

US Pat. No. 5,252,224 (Modell, Kuharich, Rooney) specifies a process for the oxidation of aqueous mixtures of organic substances, including toxic substances, in the presence of inorganic substances. For this purpose, oxygen and the aqueous mixture are separately brought to a pressure above approximately 221.3 bar and then combined to form a reaction mixture. The reaction mixture is brought to a temperature above about 374 ° C. As a result, the substantial amount of the organic material oxidizes and the run-off mixture is formed, which is cooled and its solid constituents are separated off by filtration. The oxidation reaction takes place above the critical point of pure water (t _κ = 374 ° C, P _κ = 221.3 bar). The reaction mixture is then present as a fluid phase in the supercritical state. Some of the products formed in the reaction are not dissolved by the fluid phase, but separate out as a solid in the reaction space. The apparatuses in which such oxidizing reactions are carried out in the fluid phase at conditions above the critical point of the aqueous mixture therefore tend to become clogged or deposited. The deposits deteriorate the heat transfer of the equipment, the blockages cause interruptions in operation.

For example, in the oxidation of chemical warfare agents in a supercritical, aqueous phase, metal oxides, e.g. B. arsenic oxide or inorganic salts such as. B. phosphates or sulfates arise which remain essentially undissolved in the prevailing conditions. They then cause the deposits, the disadvantageous consequences of which the operators of such plants prefer to avoid.

US Pat. No. 5,019,135 (Sealock, Jr. et al.) Describes a process for converting lignin and cellulose-containing feedstocks, such as those found in biomass, into fuel gas. The conversion takes place in an aqueous phase under pressure above 100 bar and at moderate temperatures (300 ° C to 450 ° C) in the presence of an alkaline catalyst together with a co-catalyst made from reduced nickel.

The resulting fuel gas consists essentially of methane, hydrogen and carbon dioxide. No oxygen is added, because otherwise the reduced nickel catalyst would be inactivated by oxidation. With the method described in US Pat. No. 5,019,135, biomass containing lignin can be converted into fuel gas. However, the process is not suitable for the implementation of chemical warfare agents that contain sulfur, for example, because the sulfur would poison the nickel catalyst. A note in this regard, which explains the deactivation of the nickel catalyst under the reaction conditions present in the aqueous phase, is contained in the publication [4], which was co-written by the inventors of US Pat. No. 5,019,135 has been.

European patent EP 0 402 405 (K. Andersen) describes a method with which an organic material is converted into a gas. The organic material in water in the liquid state is heated to a temperature of 200 to 450 ° C. at a pressure of 51 to 355 bar. This is done in the presence of a catalyst which consists of a compound of an element from group IA of the table of the periodic system and which further comprises a compound of an element of group IVB from the table of the periodic system.

In one embodiment of the process, zirconium dioxide Zr0 _{2 is used} as a compound of a group IVB element together with potassium carbonate K CO3 as a compound of a group IA element as a catalyst. With this catalyst, crushed barley straw or sewage sludge or toxic aliphatic and aromatic hydrocarbons are converted into non-toxic compounds. Of these hydrocarbons, trichloroethane Nitrobenzene CgH ₅ N0 ₂ and chlorophenol ClCgH ₄ OH mentioned in one example.

A mixture of different compounds is formed from barley straw, which essentially consists of CO2 (60%) and methanol (21%), but also contains C - ^ - C ^ hydrocarbon. substances, methanol, ethanol, acetone, propanol and butanol are included.

The patent EP 0 402 405 also mentions other organic material which can be converted into gas, such as waste paper, sawdust, dry sludge, cellulose wax, coal, oil sand and liquid sugar. However, it is not apparent from this patent specification EP 0 402 405 that other organic compounds containing arsenic or phosphorus can also be converted into gas by the process. Such other organic compounds are contained in the chemical warfare agents as a toxic active substance.

In one embodiment, the method described in this EP 0 402 405 also provides for a continuously operated process. In the continuous process, the gas formed by the reaction is continuously withdrawn from the reactor. For this purpose, a separate outlet connection is provided at the head of the reactor, while the liquid phase below the gas outlet connection is withdrawn from the reactor.

The continuous process operated in this way has a disadvantage. The gas formed is only partially drawn off at the top of the reactor. The proportion of the gas which is dissolved in the aqueous phase under the reaction pressure is not removed. Since the aqueous phase is recycled and mixed into the fresh feed mixture, the liquid phase in the reactor is enriched with the gas portion which dissolves under pressure until saturated. Since the gas formation takes place in the liquid phase, the reaction equilibrium is shifted to the disadvantage of the new gas formation and the new gas formation takes place less effectively or the possible equilibrium concentration is only incompletely established. This disadvantage prevents chemical warfare agents in such a continuous process with the required high degree of implementation can be implemented. Unreacted portions of the toxic active ingredients or only partially converted cracking products of lower toxicity remain in the liquid phase.

The explanations given above show that there is a need to find a method by means of which chemical warfare agents can be converted into non-hazardous substances better than previously possible.

The rocket fuels used in military aircraft are described in [5]. US Pat. No. 5,133,877 (Rofer et al.) Publishes a process for converting hazardous substances by means of oxidation thereof in supercritical water, the addition of substances having an oxidizing effect being dispensed with. Explosives and cannon propellant charges are mentioned as such hazards which contaminate the atmosphere with nitrogen oxides in the event of an explosion or in the event of combustion.

This process converts the hazardous substances into harmless substances at supercritical pressure and at the same time acting supercritical temperature. This does not succeed, for example, with ammonium perchlorate NH4CIO4 if the reaction temperature for the conversion is kept at or below the critical temperature of the pure water (t _ = 374 ° C.) because chlorine tetraoxide CIO4 is formed in the process. These discussions show that there is a need to find a way to convert rocket fuel into harmless substances better than has been possible to date.

The present invention relates to a method for the disposal of chemical weapons in a continuously operated process. In this process, the weapon chemical substance is first suspended and / or dissolved with water and an alkaline, catalytically active additive is added to the aqueous mixture. The mixture of ingredients is thus generated.

Then the feed mixture with liquid conveyors such. B. brought a high pressure pump to the reaction pressure.

The feed mixture kept at the reaction pressure is first preheated with regenerative heat exchange media.

The preheated feed mixture is then heated to the reaction temperature using heat supply means.

The feed mixture heated to the reaction temperature is passed over a catalyst bed with catalytically active zirconium dioxide, the catalytic reactions resulting in the hot converting mixture, which is essentially free of chemical weapons substances.

The hot convert mixture formed is then passed through the regenerative heat exchange medium mentioned in step c) and the convert mixture is cooled by releasing its heat to the feed mixture kept at the reaction pressure and preheating it.

Finally, the cooled converting mixture is expanded in a pressure-reducing agent to essentially a pressure close to the ambient pressure, after which the relaxed converting mixture is introduced into a phase-separating agent, in which the reaction products contained in the converting mixture and formed in step e) are converted into a gaseous phase, in an oil-containing phase and be broken down into an aqueous phase and the three phases formed are removed separately from the phase separating agent and fed to the respective further treatment. The process according to the invention is characterized in that the reaction temperature is essentially maintained at the critical temperature of the pure water, but never reaches or exceeds it, and in that the reaction pressure is between 100 and 1,000 bar.

Surprisingly, the present invention has a number of advantages. The reaction takes place in an aqueous, liquid phase under elevated pressure (100 to 1,000 bar) and elevated temperature (below 374 ° C). Water is pronounced chemically reactive under these conditions. Therefore, the reaction kinetics of the reactions involved in the reaction result in shorter residence times than at low pressure and / or temperature.

The essential parameter for this reaction kinetics is the density of the aqueous phase, which can assume 0.5 g / cm ° to 0.9 g / cm ^J in the process of the present invention. In contrast, the density of supercritical water is half that.

The method of the present invention has a substantially reducing effect on the toxic substances in the chemical warfare agent mixtures.

The acid formers nitrogen, phosphorus and sulfur introduced with the feed mixture are converted into water-soluble salts. Because of the reducing reaction, the formation of strongly corrosive acids is avoided, and these salts cannot form any deposits within the required solubility limits. The salts are discharged from the apparatus with the aqueous converting mixture free of deposits. Metals from the organic compounds used are also discharged in the form of their salts. In a similarly advantageous manner, the halogens introduced with the feed mixture, for example fluorine, chlorine, bromine, iodine, are converted into water-soluble salts. Deposits of these salts cannot form as long as the solubility of the aqueous phase is not exhausted. However, the aqueous phase dissolves larger amounts of salt than supercritical water.

The method of the present invention has yet another advantage. The chemical warfare agents are mixtures which also contain other auxiliaries which consist of organic chemical compounds. These auxiliaries are converted into absolutely harmless residues with the same reactivity as the actually toxic active ingredients. Therefore, the combat substance formulations taken from the weapons or the storage containers can be fed directly into the process according to the invention without any further pretreatment steps which are dangerous.

In one embodiment of the method it is provided that the residence time of the heated feed mixture in the catalyst bed is between 30 seconds and 720 seconds. In this way, the process is adapted to the respective reaction kinetics of the weapon chemical substances used. Surprisingly, the selection of this process parameter allows the process to be used to the full extent of the range of weapon chemical warfare agents.

Another embodiment of the process according to the invention provides for the heated feed mixture to be passed over the catalyst bed a number of times and only to bring the fresh feed mixture to the reaction pressure required to set the reaction pressure. Here, the ratio of the freshly introduced feed mixture amount to the amount recirculated via the catalyst bed assumes small values deviating from one, between 0.01 and 0.2 lie. With these values, the process can be operated at a very high level of safety because the toxic inventory fed into the process is greatly diluted on the one hand, and on the other hand because the mean residence time of the toxic substances is a multiple due to the high recirculation rate of the aforementioned values.

This highly reliable process control is surprisingly cost-effective because only the drive power of the circulation pump has an impact, but this is low because the circulation pump can only be used to counter the pressure drop in the catalyst bed.

1 shows a density / temperature diagram for pure water with registered isobars. The range of the state variables within which the catalyzed reactions are carried out in the catalyst bed of the reactor is highlighted by the hatching. Some of the reactions taking place simultaneously in the catalyst bed are given below:

CO conversion reaction:

CO + H ₂ 0> C0 ₂ + H ₂

Steam reforming reaction:

C + HH ₂₂ 00 CO + H-

C _n H _m + x H ₂ 0> n C0 ₂ + (m / 2 + x) H ₂

CH ₄ + H ₂ 0> CO + 3 H ₂

CH ₄ + 2 H ₂ 0> C0 ₂ + 4 H ₂

Hydrogenation reaction:

_C = C- + 2 H -> -CH ₂ -CH ₂ -

Dehalogenation reaction:

C _n H _m -Cl + KOH •> + KC1 Dehydrohalogenation Reaction:

C _nHm -Cl + KOH> C ^^ + H ₂ 0 + KC1

From the above reaction equations it can be seen in which way the typical reaction products contained in the conversion mixture carbon dioxide, salts and alcohols are formed. The specified reaction equations are only selected as prototypes for a group of similar reactions.

2 shows a block flow diagram of the method according to the invention.

3 shows a process flow diagram for the present invention, according to which the cooled conversion mixture is relaxed.

4 shows a process flow diagram for the present invention, according to which the hot converting mixture is first relaxed and then cooled.

2 shows a block flow diagram of the method for disposing of weapon chemical substances in a continuous process. The whole process works in the liquid phase.

A weapon chemical substance 11 is fed continuously or quasi-continuously into a mixture generation stage 101. In the case of quasi-continuous feeding, a portion is first taken from the containers available for feeding and a portion of process water 12 is mixed in a separate batch, then suspended or dissolved. A portion of the alkaline, catalytically active additive 10 is then mixed into this batch. Sodium hydroxide solution NaOH or potassium hydroxide solution KOH are added as additive 10.

These lyes bind those in the subsequent catalytic

Reaction of the halogens released by chemical weapons

(Fluorine, chlorine, bromine, iodine) in the form of water-soluble salts such as e.g. NaCl and KC1.

The finished batch is then fed continuously into the preheating stage 102 as a fresh feed mixture, while at the same time another, second batch is prepared for the subsequent subsequent feed by mixing in portions.

If the weapon chemical substance introduced into the batch is a solid rocket fuel, such as, for example, a composite fuel made of polymer fuel with an inorganic oxidizer incorporated into it, the suspended solid-like composite fuel content in the fresh feed mixture can be adjusted to between 0.5% and 20% by weight become. The particles of the comminuted, solid rocket fuel may assume values between 1 and 2 mm with regard to their grain size.

The weight fraction of the solid rocket fuel in the aqueous feed suspension depends on the energy content of the composite system. Since the fuel energy is released as heat in the reaction stage 104, it is preferable to suspend just as much solid rocket fuel in the batch that the preheating stage 102 works autothermally. In the case of autothermal operation, the feed mixture is already preheated to the reaction temperature (about 350 ° C.) and released to the reaction stage 104. The method according to the invention has a decisive advantage at this point, because the admixture of the solid rocket fuel into the aqueous suspension is not very sensitive with regard to unintentional burn-up or premature detonation proves and, moreover, this hazardous sensitivity can be reduced in a targeted manner by adding only a small proportion which is oriented towards the lower limit of the stated solids content range.

If the weapon chemical substance introduced into the batch is not water-soluble and mechanically very difficult to comminute, as is the case with the viscous sulfur LOSTs, an organic emulsifier and / or a dispersant can be added to the batch. These additives are also converted into harmless residues in the reaction stage 104, the degradation of the weapon chemical substances being in no way impaired.

The preheating stage 102 essentially works as a regenerative heat exchanger.

The fresh feed mixture is heated in the preheating stage 102 by being brought to indirect heat exchange with the hot converting mixture which emerges from the reaction stage 104.

If only insufficient heat is released in the reaction stage 104, the fresh feed mixture must be heated to the reaction temperature in the heater stage 103. This is done by supplying heat generated outside the process circuit.

The heat exchanger in the heater stage 103 can be heated either by heat transfer oil or by electric current.

The fresh feed mixture emerges from the heating stage 103 with a final temperature of approximately 350 ° C. and is introduced into the reaction stage 104 at this temperature. The heated feed mixture fed into reaction stage 104 is an alkaline, aqueous solution and / or suspension. It is catalytically treated in reaction stage 104 at elevated pressure, preferably between 180 bar and 265 bar, and elevated temperature, preferably between 280 ° C. and 350 ° C.

The catalyst is a fixed bed catalyst with zirconium dioxide Zr0 ₂ as a catalytically active substance. The residence time of the aqueous solution and / or suspension in the catalyst bed is between one and 20 minutes.

At a pressure of 265 bar and a reactor inlet temperature of 350 ° C, the majority of chemical weapons substances are converted into absolutely harmless residues within a dwell time of not more than 12 minutes.

The harmless residues formed depend on the type and composition of the chemical weapons used.

Above all, harmless, naturally occurring gases such as methane CH ₄ , carbon dioxide C0 ₂ , hydrogen H ₂ and ammonia NHo as well as water-soluble salts, for example NaCl, Na ₂ P0o or Na2P0 ₄ , are produced which are comparatively simple and cost-effective can be cheaply processed into a form that is harmless to the environment and can be deposited.

The aqueous conversion mixture formed in reaction stage 104 is drawn off at reaction pressure and regeneratively cooled in preheating stage 102 by transferring its heat to the stream of fresh feed mixture by means of indirect heat exchange.

The cooled conversion mixture is released in the separation stage 104 from the reaction pressure to approximately ambient pressure level and a gaseous phase 34, an aqueous phase 36 and an oil-containing phase 35 are formed. The gases formed collect in the gaseous phase 34

(C0 ₂ , CH ₄ and H ₂ ) and the one released during relaxation

Steam.

The gaseous phase 34 contains combustible gases; with these e.g. in a combustion chamber heat for heating the

Heat transfer oil used in the heating stage 103 are generated.

The oil-containing phase 35 is separated from the water-containing phase 36 by adding separation aids in the gravitational field.

The water-containing mixture obtained, enriched with oil, is also disposed of in the combustion chamber.

The remaining salt-containing water is concentrated by means of membrane filtration, and the largely salt-free filtrate is returned to the mixture generation stage 101. The enriched salt solution is transferred in crystal form in a spray tower. The crystals are deposited in barrels.

3 shows a process flow diagram according to the invention. The chemical weapon 12 is either suspended in a mixer 5 with water and / or dissolved in water. For this purpose process water 12 is fed into the mixer 5.

An alkaline, catalytically active additive 10 is continuously added to the aqueous mixture 13 formed, e.g. NaOH or KOH lye.

The insert mixture 17 is thereby formed. The amount of additive 10 added is such that there is always a sufficiently basic buffered reaction system in reactor 1 in order to avoid the formation of acids and the corrosion associated therewith.

The feed mixture 17 is brought to the reaction pressure with a high-pressure pump that works without a stuffing box, for example a diaphragm pump. A glandless pump is preferable because of the toxicity of the feed mixture.

The feed mixture 17 kept at the reaction pressure is regeneratively preheated in a high-pressure heat exchanger 3.

Since an aqueous fluid is carried both on the jacket side and on the tube side of the high-pressure heat exchanger 3, it is designed in a double-tube design. This design facilitates the decontamination of the system when the disposal system is down for maintenance.

Pre-warmed feed mixture 15 is dispensed from the high-pressure heat exchanger 3.

A subset 32 of the hot conversion mixture formed in the reactor 1 is added to the preheated feed mixture 15 and is recirculated in order to increase the residence time.

This addition results in the feed mixture feed 16, which is then heated to the reaction temperature in the heater 2 and introduced into the reactor 1.

A fixed bed with catalytically active zirconium oxide is installed in the reactor.

Unless the recirculated portion of gebilde¬ in reactor 1 th hot Konvertgemisches not is 32 more than twice as much as the fresh feed mixture amount ^'which is Reak¬ tor 1 designed as a tubular reactor.

If the recirculated portion 32 is 5 to 100 times the fresh feed mixture, the reactor is equipped with a fixed bed through which radial flow flows and a comparatively large inflow cross section. The hot conversion mixture 30 formed in the reactor 1 is drawn in by the circulation pump 6. Your delivery rate is divided into the recirculated portion 32 and the diverted partial stream 31. The circulation pump 6 is preferably designed as a canned motor pump or as a pot pump with a permanent magnet coupling.

The amount of the partial stream 31 discharged corresponds to the amount of the fresh feed mixture 17.

The partial stream 31 of the hot conversion mixture 30 is cooled in the high-pressure heat exchanger 3.

The cooled converting mixture partial stream 32 is expanded in the expansion valve 7. The relaxation valve 7 is preferably designed as a corner valve. It has armored valve seats and is intended for multi-stage expansion because a two-phase fluid 33 carrying gas and liquid is produced during expansion.

This fluid is separated in the separator 8 into a gaseous phase 34, an oil-containing phase 35 and an aqueous phase 36. The phases are removed from the separator 8 for further treatment.

4 shows another process flow diagram for the present invention. The process shown there corresponds with respect to the catalytic reactions taking place in the reactor 1, to which the feed mixture feed is subjected, with those of the process shown in FIG. 3.

In the method shown in FIG. 4, the high-pressure heat exchanger 3 has been dispensed with and has been replaced by a single-pipe coil arranged in the separator 8. The discharged partial stream 31 of the hot conversion mixture 30 is expanded uncooled in the expansion valve (PIC) into the separator 8 in the method shown in FIG. 4. Thereby there is a comparatively higher proportion of water vapor in the gaseous phase 34. The heat of vaporization of this portion is recovered at the top of the separator and transferred to the coolant circuit CW. This heat can be used by means of a heat pump to heat the heater 2. The heat pump supplies the heat transfer medium circuit formed from flow 21 and return 20.

Following are examples of the application of the method according to the invention to typical weapon chemical substances.

Examples of the conversion of chemical warfare agents

Example 1: Conversion of mustard gas (bis- (2chloroethyl) sulfide, CL-CH2-CH ₂ -S-CH ₂ -CH2-C1):

1 g of mustard gas is brought into the reactor with the catalyst (mainly made of zirconium dioxide) with 10 g of 50% sodium hydroxide solution and 100 g of water at 265 bar and 350 ° C. After a dwell time of 5 to 10 minutes, the mustard gas has been completely converted. The following reactions occur: hydrogen chloride, hydrogen sulfide and glycol are produced by pure hydrolysis. Hydrogen chloride immediately reacts with the sodium hydroxide solution to form table salt and water, the table salt remaining in solution in the liquid water. Hydrogen sulfide is also immediately converted to sodium sulfide and water. Glycol is converted into methane, CO ₂ and hydrogen by the catalyst. The hydrogen generated by the steam reforming reaction (catalyzed by potassium or sodium compounds) is mostly consumed in the hydrogenation of alkenes that may have formed. Possibly. CO generated is converted by the shift reaction (CO + H ₂ 0 -> CO2 ⁺ H ₂ ). This leaves only mustard gas (CH, C0 ₂ , H ₂ ) and approx. 1.3 g of salts (NaCl, Na ₂ S) dissolved in water.

Example 2: Conversion of sarin (isopropyl methyl fluorophosphonate, (CH3) ₂ CH0-P0FCH ₃ )

1 g of sarin is introduced into the reactor with the catalyst (mainly from zirconium dioxide) with 10 g of 50% sodium hydroxide solution and 100 g of water at 265 bar and 350 ° C. After a dwell time of 10 minutes, the sarin is completely implemented. The following reactions occur: Isopropanol and methyl fluorophosphonic acid are produced by pure hydrolysis. Isopropanol is converted to propene by the catalyst at elevated temperature with elimination of water. Propene is produced by the hydrogen generated in the steam reforming reaction (is produced by potassium or sodium trium compounds catalyzed) immediately hydrogenated to propane. The hydrolysis and neutralization of phosphonic acid leads to sodium fluoride and sodium phosphate, which remains in solution in water. Methane, CO ₂ and small amounts of hydrogen are obtained as gas components.

This leaves only simple gases from the sarin (CH ₄ , C0 ₂ , H ₂ ) and approx. 1.2 g of salts (NaF, Na ₂ P0 ₃ or Na P0 ₄ ) dissolved in water.

Example: Conversion of VX (methylphosphonic acid or thoethyl (diisopropyl) aminoethylthiolester)

1 g of VX is brought into the reactor with the catalyst (mainly from zirconium dioxide) with 10 g of 50% sodium hydroxide solution and 100 g of water at 265 bar and 350 ° C. After a dwell time of max. The VX is fully implemented in 10 minutes. VX is converted into the following products via the intermediate steps of orthophosphoric acid, methane, ethanol and a sulfur-containing amine: sodium phosphate, sodium sulfide, ammonia, methane, C0 ₂ , some hydrogen and ethane. Sodium hydroxide solution also acts as a catalyst here. This leaves VX with only simple gas (CH, C0, H, C ₂ Hg) and 0.06 g ammonia (NH ₃ ) dissolved in water and 0.76 g salts (Na ₂ S, Na ₂ P0 ₃ or Na ₃ P0 ₄ ) left.

Example: Conversion of Lewisite (dichloro- (2chlorovinyl) arsan), CI (CH = CH) -AsCl ₂ )

The conversion of Lewisite with the above-mentioned method is also possible and gives sodium arsenate, methane, CO ₂ and sodium chloride (approx. 3 - 8 min. Residence time). A normal pressureless hydrolysis with sodium hydroxide solution gives ethyne instead of methane and CO ₂ with a reaction time of approx. 30 minutes. In this case, pressureless hydrolysis would be preferable to the high-pressure process for otherwise identical products. The high-pressure process would only have the advantage of a shorter reaction time. 25th

Examples of rocket fuel conversion

1st example: conversion of dimethylhydrazine (H ₃ C-HN =

NH-CH ₃ )

1 g of dimethylhydrazine is brought into the reactor with the catalyst (mainly from zirconium dioxide) with 4 g of 50% sodium hydroxide solution and 100 g of water at 265 bar and 350 ° C. After a residence time of 1 to 3 minutes, the dimethylhydrazine is completely converted. The following reactions on the catalyst occur in the event of thermal decomposition: dimethylhydrazine is converted to methane, C0 ₂ and ammonia. The amount of heat generated in a conversion under reducing conditions is significantly smaller than in the oxidation (or the process with supercritical water). There is no NO _χ or N ₂ 0. The decay reaction proceeds continuously and not spontaneously. The thermal tint of the decay reaction is absorbed by the liquid water phase. A cooler in the circuit keeps the temperature at a constant value. The sodium hydroxide solution has a catalytic effect here.

This leaves only simple gases and approx. 0.3 g ammonia dissolved in water.

Example 2: Conversion of solid fuels (basis

Cellulose nitrate and diethylene glycol dinitrate)

1 g of solid fuel is brought into the reactor with the catalyst (mainly made of zirconium dioxide) with 5 g of 50% sodium hydroxide solution and 100 g of water at 250 bar and 350 ° C. After a residence time of 1 - 3 minutes, the fuel is completely converted. In the event of thermal decomposition, the following reactions occur on the catalyst: the fuel is converted to methane, CO ₂ and ammonia. There is no N0 _χ or N ₂ 0. The heat of the decay reaction is absorbed by the liquid water phase. The implementation takes place continuously and not suddenly. It's not a sudden printer expected increase. The resulting gases are dissolved in water under reaction conditions. The sodium hydroxide solution has a catalytic effect here. This leaves only simple gases and approx. 0.4 g ammonia dissolved in water.

Claims

Patent claims

1. A process for the disposal of chemical weapons in a continuously operated process, whereby:

a) the chemical weapon is suspended and / or dissolved in water and an alkaline, catalytically active additive is added to the aqueous mixture and the mixture is thus generated;

b) the feed mixture is brought to the reaction pressure with liquid conveyors;

c) the feed mixture kept at the reaction pressure is preheated with regenerative heat exchange means;

d) the preheated feed mixture is heated to the reaction temperature with heat supply means;

e) the feed mixture heated to the reaction temperature is passed over a catalyst bed with catalytically active zirconium dioxide and the hot conversion mixture is formed in catalyzed reactions, which is essentially free of chemical weapons substances;

f) the hot converting mixture formed is passed through the regenerative heat exchange medium mentioned in step c) and the converting mixture is cooled by releasing its heat to the feed mixture kept at reaction pressure and preheating it;

g) the cooled converting mixture is expanded in a pressure-reducing agent to essentially a pressure close to ambient pressure; h) the relaxed converting mixture is introduced into a phase separating agent, in which the reaction products contained in the converting mixture and formed in step e) are broken down into a gaseous phase, an oil-containing phase and an aqueous phase which carries the dissolved salts with them;

i) the three phases formed separately from the

Phase separating agents are withdrawn and fed to the respective further treatment;

d a d u r c h g e k e n n z e i c h n e t that

- The reaction temperature is kept essentially at the critical temperature of the pure water, but never reaches or exceeds it;

- The reaction pressure is between 100 and 1,000 bar.

2. The method according to claim 1,

d a d u r c h g e k e n n z e i c h n e t that the residence time of the heated feed mixture in the catalyst bed between 30 sea. and 720 lake. lies.

3. The method according to claim 1, which also means that the heated feed mixture is passed over the catalyst bed several times and only as much fresh feed mixture is brought to the reaction pressure as is required to adjust the reaction pressure.