GB863453A - Oxidative dehydrogenation of organic compounds - Google Patents

Abstract

<PICT:0863453/IV (b)/1> Unsaturated organic compounds and hydrogen peroxide are obtained by partial oxidation of a saturated organic compound, injecting a cooling medium into the reaction products and passing the mixture through a constriction, the ratio of pressures before and after the constriction being such that sonic velocity is attained. The organic compound is preferably a hydrocarbon such as ethane, n-pentane, isopentane, 3-methylhexane, 2-methylheptane, n-octane, n-decane or n-eicosane; cyclopentane, cyclohexane, decahydronaphthalene, methylcyclopentane, or methyl cyclohexane; ethylbenzene or isopropylbenzene, which forms alkenes, cycloalkenes or alkenyl aromatics respectively. The hydrocarbon is introduced by inlet 14 into reactor 10 while oxygen, oxygen plus inert gas or air to give a mol ratio of hydrocarbon to oxygen of 3-10:1 is introduced by inlet 16, the gases being preheated to give a reaction temperature of 600-1800 DEG F. Ammonia may also be introduced. The pressure may be subatmospheric to 100,000 p.s.i.a. but preferably the pressure is about atmospheric after the constriction and 35-1,000 p.s.i.a. in the reactor. The pressure is also related to the reactor size to give a reaction time below 1 second, e.g. 0,001-0,1 second. Water is injected by inlet 22 in a mol ratio to hydrocarbon of 1-12:1 so that the temperature of the reactants is reduced after the constriction to below 600 DEG F., e.g. 50-300 DEG F. The water may contain ammonia, ammonium bicarbonate, sodium bicarbonate, potassium hydroxide or sodium bisulphite. The resultant mixture is then separated in cyclone 31 to obtain hydrogen peroxide and other liquefied products in collector 38 and vaporous products are condensed and recovered in collector 33.ALSO:<PICT:0863453/III/1> Hydrogen peroxide is obtained together with unsaturated compounds by partial oxidation of a saturated organic compound, injecting a cooling medium into the reaction products and passing the mixture through a constriction, the ratio of pressures before and after the constriction being such that sonic velocity is attained. The organic compound is preferably a hydrocarbon such as ethane, n-pentane, isopentane, 3-methylhexane, 2-methylheptane, n-octane, n-decane or n-eicosane; cyclopentane, cyclohexane, decahydronaphthalene, methylcyclopentane, or methylcyclohexane; ethylbenzene or isopropylbenzene, which form alkenes, cycloalkenes or alkenyl aromatics respectively. The hydrocarbon is introduced by inlet 14 into reactor 10 while oxygen, oxygen plus inert gas or air to give a mol ratio of hydrocarbon to oxygen of 3-10:1 is introduced by inlet 16, the gases being preheated to give a reaction temperature of 600-1800 DEG F. Ammonia may also be introduced. The pressure may be subatmospheric to 100,000 p.s.i.a. but preferably the pressure is about atmospheric after the constriction and 35-1,000 p.s.i.a. in the reactor. The pressure is also related to the reactor size to give a reaction time below 1 second, e.g. 0.001-0.1 second. Water is injected by inlet 22 in a mol ratio to hydrocarbon of 1-12:1 so that the temperature of the reactants is reduced after the constriction to below 600 DEG F., e.g. 50-300 DEG F. The water may contain ammonia, ammonium bicarbonate, sodium bicarbonate, potassium hydroxide or sodium bisulphite. The resultant mixture is then separated in cyclone 31 to obtain hydrogen peroxide and other liquefied products in collector 38 and vaporous products are condensed and recovered in collector 33.