Patented Nov. 30, 1948 2,455,205 UNITED STATES PATENT of FICE 2,455,205 COMPOSITIONs suITABLE FOR USE As GAs AND PoweR PRODUCING LIQUIDs sohn. Whetstone, West Kilbride, and James Tay i lor, Saltcoats, Scotland, assignors to Imperial -Chemical Industries Limited, a corporation of Great Britain No Drawing. Application July 17, 1946, serial No. 684,242. In Great Britain August 24, 1945 1 Claim. (C1.52-14) 1. 2 The present inventionist; concerned with the 'hydrous: chemically-stable non-volatile eutectic provision of substantially... anhydrous homoge and non-eutectic compositions that are liquid-at neous compositions suitable for use as gas- and temperatures not substantially higher than room power-producing liquids for use in explosive com temperature. positions or otherwise for instance in internal The One or more compounds which are to be combustion engines or in reaction propelled or included in the ammonium nitrate-urea compo siet propelled devices. 'sitions are ammonium nitrate fusion point de It is an object of the invention to provide pressing inorganic - salts and Organic materials chemically stable non-volatile power producing which are of low-molecular weight and are freely compositions that are liquid at or about ordinary 10 soluble-in-fused - ammonium nitrate and urea; atmospheric temperatures. . . . are not highly associated in ammonium nitrate It is known that ammonium nitrate-can-react solution (such substances are usually found to be With liquid ammonia, to form Diver's liquid, but freely water soluble in the cold); do not form this liquid is unstable: and has a considerable insoluble or sparsely soluble salts by decompo vapour pressure of ammonia...... sition with ammonium nitrate, or by co-ordina Ammonium nitrate is the most important en tion. With urea, to an extent that the desired re ergy and gas-producing Salt used in the explosives duction in the fusion3point of the ammonium ni industry, and can also be employed in conjunction itrate urea, eutectic or composition is not attained. with Oxidisable materials for the production of ... The following are examples of suitable com power in other waysithan by explosion, but to a ipounds which can be added preferably two or certain extent the crystalline form of this com more than two at a time to ammonium nitrate pound limits its application. For instance the and urea mixtures namely -ammonium sulpha amount of ammonium nitrate that can be in mate, ammonium thiosulphate, ammonium for cluded in nitroglycerine gelatine explosive com mate, ammonium acetate, ammonium thiocyan positions is limited, rather by the necessity of 2:5 ate, ammonium hypophosphite, acetamide, pro maintaining the proper compactness of the ex pionamide, anhydrous sodium acetate, methyl plosive than by the considerations of sensitive amine nitrate. 'ness. Again, fuels for internal combustion en The following inorganic salts are described by gines must be liquids capable of flow at ordinary Beilstein as giving addition compounds With urea, or only slightly raised temperatures. To dissolve 30 and are thus unsuitable as additions at least in the- annonium nitrate in water, would seriously any quantity: sodium; chloride, ammonium chlo detract from the power...producing. value of the ride, calcium chloride, zinc chloride, cadmium composition. A chemically stable substantially chloride, mercuric chloride, calcium bromide, anhydrous homogeneous composition containing magnesium bromide, calcium iodide, sodium ni the annonium nitrate, and a material -oxidisable :35 trate, silver nitrate, calcium nitrate, magnesium by it in solution at or about: room-temperatures nitrate. Would thus be of considerable value as a power The following Substances which are freely: Wa producing liquid, but so far as we are aware, such ter:soluble and of low-molecular weight have been liquid has never been...produced. -- . " found to raise the crystallising temperature of It is known that ammonium nitrate and, urea, 40 the ammonium nitrate-urea, eutectic; sodium form a binary eutectic having a melting point of perchlorate, -ammonium fluoride, ... urea, nitrate, 44.7 and containing 47%. urea (Howells, Journ. potassium dihydrogen :phosphate. These sub Chem. Soc. 1929, p. 910), and that a ternary stances are thus, unsuitable as additions. eutectic can be formed containing .45% urea, According to the present invention therefore 47.5% ammonium nitrate and 7.5% sodium ni 45 substantially anhydrous homogeneous composi trate and having a melting point of 37.1° (How :tions suitable for use as gaS and power producing ells, Journ. Chem. Soc. 1930, p.2010). It is also liquids of -ammonium-nitrate and urea include known that a ternary eutectic having a melting such quantities of one or more-of-the compounds point of 42.5 can be produced from 45.5% urea, of the -kind hereinbefore - defined that the said 52.0% ammonium nitrate and 2.5% resorcinol 50 compositions are liquid at atmospheric tempera (Hrynakowski Z. Krist. 94, p. 358 (1938)). ture ranges. We have now found that by the inclusion of one Although the ratio of the ammonium nitrate or more compounds of the kind hereinafter de to urea in the binary eutectic formed by these fined in mixtures containing, ammonium nitrate two substances is 53:47 the ratio generally pre and urea it is possible to provide substantially an- 55 ferred is 50 to 30 or 50 to 25 in order to keep

...si:Iai: 2,455,205 3 the oxygen value of the mixtures nearer "bal Eacample 5 ance.” This necessitates the choice of the one or more of the compounds hereinbefore defined to A. B C be such that they will dissolve the exceSS amir monium nitrate. Parts Parts Parts Ammonium nitrate.------45 40 50 It has been found that mixtures of the am Urea------30 30 25 monium nitrate-urea, eutectic plus about a total Ammonium formate.------10 15 0 of 20-25% of two or more of the compounds Ammonium acetate------15 5 15 hereinbefore defined have eutectics fusing in the range -10° C. to -30° C. 10 Oxygen value per gram------0.38 -0.43 -0.33 As it is usually desirable as hereinbefore mentioned, that for use in explosives the oxygen The mixture A is completely liquid at 20° C. values of the said anhydrous homogeneous ad though cooling below 14° C. induces the separa mixtures should not be allowed to become un tion of long-needle-like crystals, probably am favourably negative, the ammonium nitrate monium nitrate. content is usually arbitrarily kept in the region Mixture B, containing less ammonium nitrate, of 45-55% and consequently such liquid mixtures is fiuid at -10° C. are not true eutectic compositions, though their Mixture C is partly liquid at room temperatures. low lusion points are due to the formation of The differences in properties according to vari eutectics, ations in the ratio of four components are also The following are examples of substantially 2O shown by the following table: anhydrous homogeneous admixtures according to Eacample 6 the invention wherein the parts are parts by weight. A B C Eacd.imple i. 2 5 Parts Parts Paris Parts Ammonium nitrate------50 45 40 Urea------25 30 30 Ammonium nitrate ------50 Ammonium formate --- 5 5 5 Urea ------33 Acetamide------10 O 5 Methylamine nitrate ------17 3 0. The urea, and methylamine nitrate together Oxygen value per gram------0.34 -0.39 -0.48 give a liquid containing Suspended matter at Composition A, on cooling, first crystallises at 20° C. The ammonium nitrate is dissolved in 28° C. and is still very fluid at 20° C. The liquid portions and gives a product almost completely When cooled to 0° C. remains Supercooled but liquid at 20° C. 35 on stirring complete solidification ensues with Eacample 2 rise of temperature to 15° C. Parts Composition B is liquid at room temperatures Ammonium nitrate ------50 and crystallises partly at 15° C. Urea ------25 40 Composition C does not crystallise after 48 Methylamine nitrate ------17 hours at -10°C. Ammonium sulphamate ------8 Eacample 7 The urea, methylamine nitrate and annonium A. B sulphamate become liquid when mixed together 45 at room temperature. The ammonium nitrate Ports Parts dissolves almost completely on addition. There Ammonium nitrate------50 40 Urea------25 . 30 is little change in the amount of Suspended solid Ammonium acetate. - - - 15 15 between 18 and 55° C. The oxygen value per Acetamide------10 5 gram is -0.18. 50 Eacample 3 Oxygen value per gram. ------0.42 -0.55 Parts These two mixtures illustrate once again that Ammonium nitrate ------50 the ratio of the four components is of great Urea ------25 importance, for Whereas mixture A becomes Ammonium formate ------15 55 pasty With Suspension of crystals at 30° C. mix Ammonium Sulphamate ------10 ture B. Withstands a few hours storage at -10° C. On mixing the above four ingredients together Without crystallisation. This is due to super at a somewhat raised temperature a slightly cooling. On prolonged standing at -10° C. the Wiscous liquid is obtained. On cooling crystallisa 60 liquid becomes filled with crystals which do not tion sets in at 17° C. and the temperature rises Wholly redissolve at room temperatures. to 23° C. and the liquid becomes pasty. Eacample 8 The oxygen value per gram is -0.22. Parts Eacample 4 Ammonium nitrate ------45 65 Urea ------30 PartS Acetamide ------10 Ammonium nitrate ------50 . Ammonium acetate------5 Urea ------25 Ammonium formate ------10 Ammonium formate ------15 Ammonium hypophosphite ------10 On mixing the above five ingredients at a 70 Somewhat raised temperature a slightly viscous The above four ingredients are mixed and fused liquid is obtained. On cooling crystallisation sets together at a somewhat raised temperature. A in at 15° to 20° C. little crystallisation occurs on cooling to 21° C. We claim: but the melt is mostly liquid at room temperature. A gaS and power producing composition con The oxygen value is -0.25. 5 prising a blend of from 40 to 55 parts by weight 2,455,205 5 6 of ammonium nitrate, from 25 to 30 parts by weight of urea, and from 20 to 25 parts by Weight UNITED STATES PATENTS of ammonium nitrate freezing point depreSSaints Number Name Date Selected from the group consisting of ammonium 1,968,158 Naoum ------July 31, 1934 sulphamate, ammonium thiosulphate, ammonium 5 2.54,416 Tyre ------Apr. 11, 1939 formate, ammonium acetate, ammonium thio- 2,159,234 Taylor. ------May 23, 1939 cyanate, ammonium hypophosphite, acetamide, 2,353,147 Cook ------July 11, 1944 propionamide, and methylamine nitrate, Said blend having a fusion point in the range of FOREIGN PATENTS -10° to -30° C. 10 Number Country Date JOHN WHETSTONE. 574 Great Britain ------AD 1875 JAMES TAYLOR, 307,040 Germany ------Oct. 27, 1919 326,184 Germany ------Sept. 23, 1920 REFERENCES. CTED 380,885 Germany ------Sept. 10, 1923 The following references are of record in the l6 380,886 Germany ------Sept. 10, 1923 file of this patent: