GB1351429A - Process for producing aromatic secondary c3-c7 alkylhydroperoxides - Google Patents

Abstract

1351429 Production of aromatic secondary (C 3 to C 7 alkyl) hydroperoxides HERCULES Inc 26 May 1972 [7 June 1971] 25092/72 Heading C2C A continuous process for oxidizing a secondary C 3 to C 7 alkyl substituted aromatic hydrocarbon to the corresponding aralkyl hydroperoxide comprises; introducing said hydrocarbon into a first reaction mixture in a first oxidation zone, said first reaction mixture comprising said hydrocarbon in the liquid state, an aqueous solution of alkali and said hydroperoxide; withdrawing from said first oxidation zone at first oxidation zone oxidate part of said first reaction mixture; introducing first oxidation zone oxidate into a second reaction mixture in a second oxidation zone, said second reaction mixture comprising said hydrocarbon in the liquid state, an aqueous solution of alkali and said hydroperoxide, the concentration of said hydroperoxide in said second reaction mixture being substantially greater than the concentration of said hydroperoxide in said first reaction mixture; withdrawing from said second oxidation zone as second oxidation zone oxidate part of said second reaction mixture; introducing aqueous solution of alkali into at least said first oxidation zone; admixing with said second reaction mixture in said second oxidation zone oxygen bearing gas at least at a rate selected to establish and maintain oxygen in said second reaction mixture in stoichiometric excess relative to said hydrocarbon in said second reaction mixture; withdrawing as second oxidation zone off-gas from the upper portion of the second oxidation zone gas reaching said upper portion; admixing with said first reaction mixture in said first oxidation zone oxygenbearing gas at a rate selected to establish and maintain oxygen in said first reaction mixture in stoichiometric excess relative to said hydrocarbon in said first hydrocarbon reaction mixture at least part of said oxygen-bearing gas being second oxidation zone off-gas; and withdrawing from the upper portion of the first oxidation zone any gas reaching said upper portion. In a further embodiment of the invention the second reaction zone oxidate is introduced into a third reaction mixture in a third oxidation zone, said third reaction mixture comprising said hydrocarbon in the liquid state, an aqueous solution of alkali and said hydroperoxide, the concentration of said hydroperoxide in said third reaction mixture in said third oxidation zone being substantially greater than the concentration of said hydroperoxide in said second reaction mixture in said second oxidation zone; withdrawing from said third oxidation zone as third oxidation zone oxidate part of said third reaction mixture; admixing oxygen bearing gas with said third reaction mixture in said third oxidation zone at least at a rate selected to establish and maintain oxygen in said third reaction mixture in stoichiometric excess relative to said hydrocarbon in said third reaction mixture; withdrawing a third oxidation off-gas from the upper portion of the third oxidation zone gas reaching said upper portion; and introducing third reaction zone off-gas into said second reaction mixture in said second oxidation zone as at least part of the oxygen bearing gas admixed with said second reaction mixture in said second oxidation zone. The oxygen bearing gas admixed in either second and a third reaction mixture may be air. Examples of the hydrocarbon are cumene, a m or p cymene an α- or #-isopropylnaphthalene, a m- or p-diisopropyl benzene, 2, butyl benzene or 2-pentyl benzene. The alkali may be sodium carbonate at an aqueous concentration of 1% by wt.