US005714128A United States Patent 19 11 Patent Number: 5,714,128 Ritter 45) Date of Patent: Feb. 3, 1998 4,949,641 8/1990 Sayles .................................... 588/200 54 SEQUENTIAL BATCH CHEMICAL 5,104,524 4/1992 Eiben et al. ... 210/85 APPARATUS FOR DESTRUCTION OF TOXC 5,298,233 3/1994 Nagel .............. 42.3/580.1 ORGANIC COMPOUNDS 5,403.563 4/1995 Crosbie et al. ... 422/261 (76 Inventor: Robert A. Ritter. 407-1274 Barclay St., 5,574,203 11/1996 Noel et al. .............................. 588/203 Vancouver, Canada, V6E 1H3 Primary Examiner-Christopher Kim Attorney, Agent, or Firm-Harry M. Weiss; Jeffrey D. Moy; (21) Appl. No.: 695,005 Harry M. Weiss & Associates, P.C. 22 Filed: Aug. 9, 1996 57 ABSTRACT An apparatus process is provided for the destruction of a Related U.S. Application Data toxic organic chlorine-containing compound, especially, a chlorine- and arsenic-containing compound. The apparatus 62 Division of Ser. No. 39,889, Mar. 30, 1993, Pat No. includes a main reactor into which is introduced the 5.545,799. chlorine-containing compound, e.g., a Lewisite as a mustard (51 int. Cl. ... B01J 8/02 gas, an oxidizing agent and a pH controlling agent, the main 52 U.S. Cl. ......................... 422/211; 422/159; 422/232; reactor including a hot heat exchanger and a cold heat 588/200; 588/201 exchanger, a source of inert blanketing gas to provide an 58) Field of Search .................................... 422/211, 129, oxidation product of the organic original chlorine 422/159. 172, 187, 188, 198, 232; 588/200. containing compound. Preferably, after completion of the 201 oxidizing reaction, any residual oxidizing agent is catalyti cally decomposed. Then, the oxidation product of the origi (56) References Cited nal organic chlorine-containing compound, is preferably decomposed in a catalyst containing vessel at an alkaline U.S. PATENT DOCUMENTS pH, e.g. to a maximum final pH of about 11 in a liquid 3,719,570 3/1973 Lancy ...................................... 201/15 knockout vessel which includes a lower liquid discharge and 3,810,788 5/1974 Steyermark ... ... 588/200 an upper gaseous discharge connected to a vented absorber 4,302,424 11/1981 Miyake et al. .......................... 422/159 vessel to provide an inorganic compound, e.g. an inorganic 4,449,005 5/1984 Davis et al. .............................. 568/59 arsenic-containing-compound. Such compound can easily 4,565,787 1/1986 Bossle et al. ........................... 436/120 4,744.917 5/1988 Scavdera et al. ...... ... 252/18728 and safely be disposed of. 4,793,831 12/1988 Dirks et al. ................................. 55/20 4,797,128 1/1989 Fowler ........................................ 8/37 6 Claims, 1 Drawing Sheet U.S. Patent Feb. 3, 1998 5,714,128 5,714,128 1 2 SEQUENTIAL BATCH CHEMICAL Another undesirable feature of the hydrolysis procedure is APPARATUS FOR DESTRUCTION OF TOXC the formation of a trivalent arsenic compound, sodium ORGANIC COMPOUNDS arsenite which represents one of the most toxic forms of arsenic. Moreover, since this product is extremely soluble, CROSS REFERENCE TO RELATED some considerable difficulty is encountered in achieving its APPLICATIONS secure, permanent disposal. A second popular approach suggested in the literature This application is a division of application Ser. No. involves oxidation of the Lewisite with the aid of some 08/039,889 filed Mar. 30, 1993, U.S. Pat No. 5,545,799, the oxidizing agent, e.g., sodium hypochlorite (NaOCl), chlo entire contents of which are incorporated herein by refer rine (Cl), hydrogen peroxide (H2O) or nitric acid (HNO). CCC. Although complete oxidation may be possible with the BACKGROUND OF THE INVENTTON nitric acid, reagents, e.g. hypochlorites and peroxides were, under the conditions investigated, found to be capable of 1. Field of the Invention only partial oxidation in accordance with the following This invention relates to procedures and apparatus useful for safely destroying toxic arsenic-containing chemicals. 15 reactions: e.g., obsolete chemical warfare agents. 2. Description of the Prior Art In recent years with the global emphasis on the reduction Cl-CH=CH-AsCl-HO-HO,-Cl-CH=CH-AsOH+ of the huge stockpile of chemical warfare agents, the art has 2HC1 (3) been confronted with the problem of safely destroying and disposing of a variety of obsolescent chemical warfare In each instance, a final product of the reaction is a agents, e.g., mustard gas and Lewisite. chlorovinyl arsonic acid which, though less noxious than the Large quantities of chemical warfare agents, in various original Lewisite, is nevertheless highly toxic and represents forms, are contained in a wide spectrum of munitions 25 a significant final disposal problem. ranging from tactical ordnance to ballistic missiles, while It should be noted that products analogous to the arsonic equally large quantities are found in storage vessels with acid produced by the oxidation of Lewisite I are derived capacities ranging from a few grams to several tonnes. The from similar oxidations of Lewisite II and Lewisite III and problem of treatment and disposal is, therefore, severely that these constitute comparable disposal problems. complicated, not only by the extreme toxicity of quite 30 infinitesimal quantities of these agents, but also by the need SUMMARY OF THE INVENTION to simplify their recovery and to minimize the number of Aims of the Invention transfer and handling steps. In view of these considerations, a more attractive Where the technique of incineration is permitted, certain approach to the neutralization of the Lewisites would be of these agents, including mustard gas and the nerve gases, 35 based on some form of chemical decomposition, especially may be totally destroyed through thermal oxidation, since if this procedure could be accomplished at moderate tem the products of combustion, e.g., sulfur dioxide, may be peratures and if the resulting arsonic compounds were readily contained and prevented from escaping to the atmo readily disposable and of minimal toxicity. sphere. One object of the present invention is to provide a novel On the other hand, the Lewisites; i.e., dichloro(2- apparatus for the carrying out of the above chemical destruc chlorovinyl)arsine, bis(2-chlorovinyl)chloroarsine and tris tion which utilizes unsophisticated processing equipment (2-chlorovinyl)arsine), which comprises approximately 36 and procedures. weight percent arsonic, upon combustion produce the highly Statements of Invention toxic arsonic trioxide. Under conditions normally experi 45 The present invention provides a sequential process for enced in incinerator operation, it is extremely difficult to the destruction of a toxic organic chlorine-containing com limit the release of this contaminant to the atmosphere at pound comprising the steps of: (A) carrying out an oxidation acceptably low rates. reaction between the chlorine-containing compound and an Numerous chemical neutralization techniques have been oxidizing agent, while maintaining the temperature and the proposed in the literature based on an alkaline oxidation, pH within preselected ranges, thereby to provide an inter e.g., as taught in Canadian Patent No. 304.110 patented Sep. 50 mediate organic chlorine-containing oxidation product of 23, 1990 by C. D. Carpenter. A large proportion of these the original toxic organic chlorine-containing compound; techniques are based on hydrolysis of the Lewisite I in an and (B) converting the intermediate organic chlorine aqueous alkaline medium. The reaction involved may be containing oxidation product into easily disposable inor represented by the equation: 55 ganic compounds. Cl-CH=CH-AsC1-6NaOH-NaAsO+CH=CH-3NaCl-- The present invention also provides a sequential batch 3HO (1) chemical apparatus comprising: (A) a main reactor; (B) a Although the hydrolysis approach, especially at some source of a first chemical reactant operatively connected to what elevated temperatures, is capable of effectively an inlet to the main reactor; (C) a source of a second destroying virtually all of the principal Lewisite specie, chemical reactant operatively connected to another inlet to known as Lewisite I, the associated species, Lewisite II and the main reactor; (D) a source of a third chemical reactant Lewisite III (previously generically-termed “the Lewisites”) operatively connected to yet another inlet to the main are considerably more resistant to hydrolysis and will, to a reactor; (E) a source of an inert blanketing gas operatively considerable extent survive this treatment. The secondary connected to still another inlet to the main reactor; (F) an species, though milder vesicants than the principal analogue, 65 interim storage tank selectively operatively connected to an are nonetheless toxic and cannot be tolerated as a component outlet from the main reactor; (G) a hot exchanger selectively of the reaction products. operatively connected to the outlet from the main reactor 5,714,128 3 4 and selectively operatively connected to a main inlet to the hence, foaming. The decomposition reaction, which reduces main reactor vessel; (H) a cold exchanger selectively opera the residual peroxide to less than 0.1%, may be represented tively connected to the outlet from the main reactor and by the equation: selectively operatively connected to a main inlet to the main reactor; (I) a catalyst-containing vessel selectively opera (4) tively connected to an outlet from either the hot exchanger During the peroxide removal process, the pH is main or the cold