EPatiented July 27, 1943 2,325,065 UNITED STATES PATENT OFFICE 2,325,065 EXEPEOSEWE CORA iPOSETION Robert W. Hawrence, WiERhingteia, Deli., assignor to Heretaeg Powder Cornparay, Wiggington, FDel, a corporation of Delaware No trawing. Application November 2, 1940, Sesii No. 36,38. 8 (Cairns. (Ch. 52-5) This invention relates to explosive composi in acid-proof containers, such as, for example, tions containing a nitroparaffin as an essential plastic, glass, coated metal, etc. ingredient thereof and particularly to an explo By Way of illustration, have shown in Table Sive composition containing nitromethane and four examples of nitric acid and nitronethane nitric acid. Inixtures, one example of a nitric acid and nitro Liquid nitrogen tetroxide explosives have been ethane mixture and one example of a nitric acid known for many years. Such explosive compo and 1-nitrobutane mixture. The compositions sitions usually comprise mixtures of liquid containing nitromethane vary from 15% HNO3 nitrogen tetroxide with kerosene, gasoline, car (98%) and 85% nitromethane to 63% HNO3 bon bisulfide, etc. Explosive compositions con 0. (98%) and 37% nitronethane. Oxygen balances taining nitrous acid are also known, the pro vary from -24% to +24.7%. The explosive cedure in forming these being to nitrate petro mixtures shown in Table all detonate With a leum with nitrous acid and use the product, so brisance which is approximately equivalent to formed in admixture with nitrous acid as an that of nitrogylcerin and can be satisfactorily explosive. 5 detonated with a commercial No. 8 electric Explosive compositions of the above nature blasting cap. For example, the mixture of nitro are subject to the disadvantage that they inter nethane (61.2%) and HNO3 (38.8%) has an act chemically when stored, thus losing some of oxygen balance of 0.0%, a density of 1.24 g./cc., their effectiveness. and a detonation rate of 6650 m./sec. It is to There is the further disadvantage that such 20 be understood that the proportions of nitroethane explosive compositions normally contain high and -nitrobutane may be varied with results proportions of a low boiling constituent which six milar to those obtained with nitromethane. renders them difficult to handle. It is an object of this invention to provide an Table i. improved explosive composition containing a nitroparaffin and nitric acid. Examples It is a further object of the invention to pro vide an improved explosive composition which A. B C D E F is comparatively pleasant and easy to handle. HNO3 (98%) ------percent-- 15 19 58 63 6C 72 It is a still further object of the invention to 30 Nitromethane------do---- 85 8. 42 37------provide an improved explosive composition which Nitroethane------do------does not appreciably interact chemically when l-nitrobutane.------do------Oxygenbalance.Idol. stored. A further object of the invention is to provide an improved explosive composition. Which can be It has also been found that the nitric acid readily detonated by commercial blasting caps nitronethane mixture may be considerably di but which is only slightly sensitive to impact. luted with water and still provide an explosive Another object of the invention is to provide composition which will readily detonate. Exam an explosive composition having a lower freezing ples of these explosive mixtures are shown in 4) Table 2. They may be detonated with a No. 8 point due to the inclusion of the nitromethane. electricolasting cap and have a detonation rate Further objects will appear hereinafter as the approximately the same as that of a gelatin description proceeds. dynamite. The objects of my invention are in general ge 2 carried out by providing an explosive composie 45 tion comprising a mixture of nitromethane and nitric acid. Other nitroparaffins hay be used and preferably those having the least negative oxygen balances such as s-dinitroethane, 3 dinitropropane, etc. 50 HNOs (84%) ------per cent-- 42 ----- In accordance with a preferred form of the HNO3 (70%).------do------47 invention Inix a liquid nitroparaffin such as Nitromethane------do---- 58 63 nitromethane with concentrated nitric acid. in Oxygen balance------do-----0.4. 0 suitable mixing equipment to form a solution. 1 Or-HNO. 35.3%, HO 6.7%. Such mixing equipment preferably includes a 55 Or-HNOa 33%, HO 14%. cooling coil or jacket to dissipate the heat of too much dilution of the nitronethane nitric solution. Any suitable cooling medium such as acid mixture will, however, produce a mixture ice cold water. or cold brine may be circulated which does not fire with a No. 8 electric blasting through the cooling coil or jacket. cap. Table 3 gives the results of four tests made The explosive mixture so prepared is packed 60 on compositions using a constant ratio of nitric 2 2,825,065 acid to nitromethane, i. e., 0.627 to 1 and in sitive to impact though readily detonated by which the percentage of Water was varied from commercial blasting caps thus being safer to 7.3 to 30.1. It will be noted that the composi handle, While having at the same time a high det tions containing respectively 17.3, 20.6 and 25.4 onation rate. They have a lower freezing point per cent water shot with a No. 8 E. B. cap while than prior known liquid explosive mixtures and the composition containing 30.1 per cent Water are very simple and easy to compound. failed to fire. A further advantage of explosive mixtures ac be 3 cording to the present invention is that the nitric acid readily forms a Solution. With the above I II III Iv O mentioned nitroparaffins in contrast, for exam ple, to the petroleum hydrocarbons, such as HNO3------per cent. 31.9 30.6 28.7 27.0 hexane, which are not miscible with nitric acid. CHNO------do.... 50.8 48.8 45.9 42.9 It will be understood that the details and ex HO------do---- 1.3 20.6 25. 30. amples hereinbefore set forth are illustrative only 100.0 100.0 100.0 100.0 15 and that the invention as broadly described and Oxygen balance------do... --0.2 -0.2 --0.2 -0.2 claimed is in no way limited thereby. Shot or failed with No. 8 E. B. What I claim and desire to protect by Letters CP------S S S E. Patent is: While generally Speaking, the maximum i. An explosive composition comprising con strength is developed by explosives which con centrated nitric acid and nitromethane. tain just sufficient oxygen to convert the carbon 2. An explosive composition comprising con to carbon dioxide and the hydrogen to water, centrated nitric acid and nitromethane said corn excellent explosive mixtures can be obtained position having an oxygen balance between about with positive and negative oxygen balances, -25 and about --25%. Thus mixtures of nitromethane and nitric acid 25 3. An explosive composition comprising a mix varying from 85% nitromethane and 15% con ture of concentrated nitric acid and nitroethane. Centrated nitric acid (98%) to 37% nitrometh 4. An explosive composition comprising a mix ane and 63% concentrated nitric acid (98%) ture of concentrated nitric acid and nitropro form powerful explosives. (See Table 1.) pale. It is to be understood, of course, that nitro 30 5. An explosive composition, comprising con paraffins other than those shown in Tables 1 centrated nitric acid and nitroethane, said con and 2 may be used for the purposes of the pres position having an oxygen balance between about ent invention. Thus, for example, 1- or 2-nitro -25 and about --25%. y propane, primary or tertiary nitrosobutane, 6. An explosive composition comprising con Symmetrical dinitroethane, 1,3-dinitropropane, 35 centrated nitric acid and nitropropane, said either alone or admixed together may be used. composition having an oxygen balance between I prefer, however, to use nitroparaffins with a about -25 and about --25%. relatively Small negative oxygen balance such 7. An explosive composition comprising an ad as nitromethane whose oxygen balance is mixture composed of nitric acid and a lower -39.3%. O nitroparaffin selected from the group consisting Explosive compositions according to the pres of nitromethane, nitroethane, dinitroethane, ent invention. Will be found extremely useful in nitrobutane, nitroisobutane, nitropropane and quarry blasting and Open-pit metal mining where dinitropropane. m a powerful explosive with a high rate of detona 8. An explosive composition comprising an tion is needed. These exposives are also useful 45 admixture having an oxygen balance between for Warious military purposes. about -25% and about --25% and composed of My explosive compositions are advantageous nitric acid and a lower nitroparaffin selected . in many respects. Thus, there is very little . from the group consisting of nitromethane, chemical interaction under ordinary conditions nitroethane, dinitroethane, nitrobutane, nitro of storage. They are generally pleasanter and 50 isobutane, nitropropane, and dinitropropane. easier to handle than the more volatile nitrogen tetroxide explosives. They are only slightly sen ROBERT W. LAWRENCE.