3,139,327 United States Patent Office Patented June 30, 1964 . 2 the quaternary ammonium superoxides, we prefer at pres 3,139,327 ent to use tetramethylammonium superoxide. PROCESS FOR MAKING OZONIDES BY REACTING OZONE WITHSUPEROXDE - The quaternary ammonium superoxides are a relative Mervin D. Marshall, Fombell, and Raymond F. Bratton, ly new class of compounds. They can be made by several Evans City, Pa., assignors to Callery Chemical Com methods, such as the metathetic reaction of the quaternary pany, Pittsburgh, Pa., a corporation of Pennsylvania ammonium halide or hydroxide with potassium super No Drawing. Filed Mar. 7, 1960, Ser. No. 13,383 oxide in liquid ammonia, or by electrolysis of the quater nary ammonium halide in liquid ammonia, using, for ex 14 Claims. (CI. 23-184) ample, a magnesium anode and a platinum cathode and This invention relates to a new method for the produc 10 a temperature between -65 C. and -80 C., followed tion of ozonides. by reaction of the electrolysis products with molecular Ozonides, as referred to throughout this specification, oxygen. Such compounds and processes for their prepara are compounds having the Oar anion. Such compounds tion are also disclosed in the copending, co-assigned ap have in the past at times been referred to as ozonates, but plications of Hashman and Renforth Serial No. 92,090, presently approved nomenclature names these compounds 15 filed February 27, 1961, which is a continuation-in-part as OZonides. of abandoned application, Serial No. 832,864, filed Au Heretofore, no good way to make ozonides has been gust 10, 1959, and Hashman and Berkstresser Serial No. known. Certain methods which were used have invariably 97,388, filed March 21, 1961, which is a continuation-in resulted in very low yields and involve difficult recovery part of abandoned application Serial No. 832,863, filed and purification techniques. These methods also were 20 August 10, 1959. specific in their nature and were not applicable to any Alkaline earth metal ozonides are also made by our wide variety of ozonides. Because of the relative insta method from the corresponding alkaline earth metal bility of these compounds, these tedious processes have superoxides. Thus, for example, calcium superoxide, not been satisfactory because the products which are ob CaO4, barium superoxide, BaO4, and strontium super tained tend to decompose during the processing steps re 25 oxide, SrO4, can each be used to produce the correspond quired. ing ozonide by the method described herein. It is an object of this invention to provide a new method The temperature at which the reaction is carried out is of making ozonides which is applicable to the production not critical, but it should be considered in order to obtain of several such compounds, including ozonides of alkali the best yields. Ordinary ambient temperatures, i.e., metals, alkaline earth metals and quaternary ammonium 30 about 20 to 30 C, can be used, but because of the tend cations. - ency of the ozonides to decompose at even moderately Another object is to provide a method of making ozo elevated temperatures it is preferred to use low tempera nides in which higher yields are obtained and less compli tures. Temperatures as low as -80° C. and lower are cated procedures are required than in the prior known feasible for use in carrying out the process, but the reac methods. 35 tion at such low temperatures is quite slow. The pre Still other objects will become apparent from time, to ferred temperature is about 0° C., where the reaction . time hereinafter. . . . . takes place at a satisfactory rate while little or no de The basis for this invention is our discovery that ozone composition is ordinarily encountered. Higher tempera will react with certain superoxides to produce the corre tures than 30° C. should be avoided, except in the case sponding ozonide in yields much better than could be 40 of the more stable ozonides, e.g., tetramethylammonium obtained by any other method. The process does not ... ozonide, in which case moderate heating can be used if require special conditions and recovery is effected in a desired. In all cases, the course of the reaction is marked relatively simple and straightforward manner. Using by a pronounced color change; that is, as the ozonide potassium as an example, the reaction takes place in ac is produced, the reaction mixture gradually becomes an cordance with the following equation: 45 intense red. If decomposition of the product is en countered, the color fades; thus with any particular reac KOHO >KO3--O2 tion system the effect of the reaction conditions can easily Any alkali metal superoxide can be used in the practice be observed and modified if necessary. of our invention. The usefulness of lithium superoxide, It is not necessary to use pure ozone in carrying out however, is limited from a practical standpoint because 50 our process. Rather dilute concentrations of ozone and it is unstable except at very low temperatures. Because oxygen, i.e., about 5% as produced in ordinary ozonizers, the superoxides are most readily available and because are satisfactory and are generally used. However, when of the desirability of the ozonides produced, the process higher concentrations are used the reaction rate is in is particularly valuable using potassium superoxide, KO2, creased and more product is obtained in a shorter time. and sodium superoxide, NaO2, although the other alkali 55 Both the superoxides and ozonide products are decom metal superoxides, such as those of rubidium and cesium, posed by water so that moisture should be excluded from can also be used if desired. the reaction site and from the product obtained. Thus, Any quaternary ammonium superoxide (RAN) O2, the ozone-oxygen mixture should be free from moisture, where R is an alkyl or aryl group, can also be used in and storage containers should be blanketed with a dry our method to produce the corresponding quaternary 60 gaS. ammonium ozonide. Thus, among the quaternary am In one demonstration of the method of our invention, monium superoxides which may be used are tetraalkyl the process was carried out using 99% pure potassium ammonium superoxides, such as tetraethylammonium su superoxide, KO. The powdered potassium superoxide peroxide, tetrapropylammonium superoxide, tetrabutyl was placed on a porous plate within a closed reactor and ammonium superoxide and tetraheptylammonium super 65 the reactor was cooled to about 0° C. A dried gaseous oxide; mixed tetraalkylammonium superoxides, such as mixture, 5% ozone in oxygen, was then passed through cetyl-trimethylammonium superoxide; and arylalkylam the superoxide for about three hours, the reactor was oc monium superoxides, such as trimethylphenylammonium casionally agitated in order to break up the superoxide superoxide. Tetramethylammonium superoxide is quite and to expose fresh surfaces to the ozone. At the end of stable, and tetramethylammonium ozonate is both stable 70 this time, the product mixture was extracted with liquid and is exceedingly rich in oxygen because of its low ammonia in order to separate the product from unreacted molecular weight. Thus, in practicing our method with superoxide. After the liquid ammonia had been evapo 3,189,827 - 4. rated about 480 milligrams of a dark red solid were ob 5. A method in accordance with claim 1 in which the tained. Chemical and X-ray diffraction anlyses were alkali metal superoxide is potassium superoxide and the used to identify this product as potassium ozonide, KO3. alkali metal ozonide produced is potassium ozonide. In other such examples, other ozonides, including, for 6. A method of producing quaternary ammonium example, sodium ozonide and tetramethylammonium ozonide of the formula RNO3, where R is alkyl, which ozonide, were prepared at various temperatures from comprises reacting ozone with a tetraalkylammonium su -112 C. to about 25 C. It was found that the best peroxide and recovering the quaternary ammonium ozon yields were obtained at about 0° C. or slightly above. ide thus produced. Analysis and positive identification of the products was 7. A method in accordance with claim. 6 in which the made through X-ray diffraction analysis. It was further 10 - reaction is carried out at a temperature about 0° C. demonstrated that the process is applicable to alkaline 8. A method in accordance with claim 6 in which the earth metal superoxides to produce alkaline earth metal oZone is admixed with oxygen. ozonides, such as barium ozonide and calcium ozonide. 9. A method in accordance with claim 6 in which the The ozonides which are made by the method of our . tetraalkylammonium superoxide is tetramethylammonium invention have several uses. They may be used as oxi 5 Superoxde and the tetraalkylammonium ozonide produced dizing agents, where they exhibit powerful properties such is tetramethylammonium ozonide. that organic compounds can be oxidized to carbon, di 10. A method of producing alkaline earth metal ozon oxide, thereby providing an analytical method for de- . . ides, MO6 where M is an alkaline earth metal, which com termining the amount of carbon in such compounds. ihe prises reacting ozone with alkaline earth metal super ozonides can also be used as a source of oxygen, as, for 20 oxide, and recovering the alkaline earth metal ozonide example, in self-contained breathing apparatus or in con thus produced. . fined spaces such as may be encountered in submarines. 11. A method in accordance with claim 10 in which Oxygen is released from these compounds upon contact . the reaction is carried out at a temperature about 0° C. with moisture so that by passing exhaled air containing 12. A method in accordance with claim 10 in which moisture through a container of ozonides in suitable ap 25 the ozone is admixed with oxygen. paratus fresh oxygen is produced. The equipment used 13. A method in accordance with claim 10 in which may be similar to well-known apparatus used to produce the alkaline earth metal Superoxide is barium superoxide breathing from superoxides. and the alkaline earth metal ozonide produced is barium According to the provisions of the patent statutes, we ozonide. - have explained the principle and mode of practicing our 30 14. A method in accordance with claim 10 in which invention and have described what we now consider to the alkaline earth metal superoxide is calcium super be its best embodiments. However, we desire to have it oxide and the alkaline earth metal ozonide produced is understood that, within the scope of the appended claims, ... calcium ozonide. the invention may be practiced otherwise than as specifi References Cited in the file of this patent cally described. 35 UNITED STATES PATENTS We claim: 1. A method of producing alkali metal ozonides, MOa 2,784,061 Cunningham ------Mar. 5, 1957 where M is an alkali metal, which comprises reacting . . OTHER REFERENCES ozone with an alkali metal superoxide and recovering 40 Strecker et al.: "Chemische Berichte,” vol. 53, part the alkali metal ozonide thus produced. II, pp. 2096-2101, 2102, 2105-2107, 2110-2113 (1920). 2. A method in accordance with claim 1 in which the Mellor: "Comprehensive Treatise on Inorganic and reaction is carried out at a temperature of about 0° C. Theoretical Chemistry," vol. 1, page 908 (1922). 3. A method in accordance with claim 1 in which the Doklady Akad. Nauk S.S.S.R., vol. 77, pp. 69-72 ozone is admixed with oxygen. . - 45 (1951). . . . - 4. A method in accordance with claim 1 in which the Doklady Akad. Nauk S.S.S.R., vol. 118, No. 1, pp. 125 alkali metal superoxide is sodium superoxide and the 127 (1958); found in Consolidated Translation Survey, alkali metal ozonide produced is sodium ozonide. December 1958, No. 12, January 21, 1959, page 71.