Patent GB-434311-A (GB)
Title: An improved manufacture of oxidation products from hydrocarbons
Filed: 1934-10-12
Abstract: Petrolatum or slop wax is treated to reduce its oil content to 25 per cent or less, preferably to below 20 per cent, and is then oxidized, either directly or after distillation, which may be accompanied or followed by cracking or dehydrogenation.  The reduction of the oil content of the petrolatum or slop wax may be effected by extraction with a selective solvent for the oil.  The wax of reduced oil content may then be distilled without decomposition at 600 DEG  F., or it may be cracked at 850--900 DEG  F. and atmospheric or reduced pressure. Dehydrogenation may be effected at 850--900 DEG  F., at atmospheric or slightly raised pressure in the presence of a catalyst; specified catalysts are oxides and (or) sulphides of metals of the sixth group admixed or not with oxides, hydroxides or carbonates of metals of the third or fourth groups which form difficultly reducible oxides, e.g. alumina or thoria; hydrogen may be present during dehydrogenation. Oxidation is then effected in the liquid phase at a temperature below 400 DEG  F. with air or other gas containing free oxygen; p aluminium-lined vessels may be used, and a catalyst may be present, e.g. a small amount of previously oxidized wax or a salt of manganese, cobalt or aluminium with stearic, oleic or resinic acids, or with acids produced by the oxidation of wax.  Oxidation may be effected continuously or intermittently, preferably under such conditions that a product having a saponifiable content of 20--70 per cent is obtained; the product may then be purified by known saponification, distillation or extraction methods.  In the examples, (1) petrolatum is treated with ethylene dichloride at 160 DEG  F., and the mixture is chilled to about 70 DEG  F.; the precipitated wax is filtered and washed, and then distilled at 780 DEG  F. and 40 mm. pressure; finally, the distillate is blown with air at about 300 DEG F.; (2) wax obtained as in example 1 is distilled at 200 mm. pressure or (example 3) at atmospheric pressure, and then oxidized as in example 1; the saponification and acid numbers of the products are specified.ALSO:Petroleum or slop wax is treated to reduce its oil content to 25 per cent or less, preferably to below 20 per cent, and is then oxidized, either directly or after distillation, which may be accompanied or followed by cracking or dehydrogenation.  The reduction of the oil content of the petrolatum or slop wax may be effected by extraction with a selective solvent for the oil; specified solvents are (a) low-boiling hydrocarbons such as ethane, propane or butane or the corresponding olefines or mixtures of such hydrocarbons, or (b) chlorinated hydrocarbons such as ethylene dichloride, or (c) naphtha and like higher hydrocarbons, which are preferably used in association with other non-solvents for wax, such as alcohols, ketones, organic acids and esters; specified alcohols are methyl, ethyl, isopropyl, n- and sec.-butyl, and amyl alcohols; specified ketones are acetone, methylethyl ketone, and diethyl ketone; specified esters are acetates and formates; acetic acid is a suitable acid.  The wax of reduced oil content may then be distilled without decomposition at 600 DEG  F., or it may be cracked at 850--900 DEG  F. and atmospheric or reduced pressure. Dehydrogenation may be effected at 850--900 DEG  F. at atmospheric or slightly raised pressure in the presence of a catalyst; specified catalysts are oxides and (or) sulphides of metals of the sixth group admixed or not with oxides, hydroxides or carbonates of metals of the third or fourth groups which form difficulty reducible oxides, e.g. alumina or thoria; hydrogen may be present during dehydrogenation. Oxidation is then effected in the liquid phase at a temperature below 400 DEG  F. with air or other gas containing free oxygen; aluminium - lined vessels may be used, and a catalyst may be present, e.g. a small amount of previously oxidized wax or a salt of manganese, cobalt or aluminium with stearic, oleic or resinic acids, or with acids produced by the oxidation of wax.  Oxidation may be effected continuously or intermittently, preferably under such conditions that a product having a saponifiable content of 20--70 per cent is obtained; the product may then be purified by known saponification, distillation or extraction methods.  In the examples, (1) petrolatum is treated with ethylene dichloride at 160 DEG  F. and the mixture is chilled to about 70 DEG  F.; the precipitated wax is filtered and washed, and then distilled at 780 DEG  F. and 40 mm. pressure; finally, the distillate is blown with air at about 300 DEG  F.; (2) wax obtained as in example 1 is distilled at 200 mm. pressure or (example 3) at atmospheric pressure, and then oxidized as in example 1; the saponification and acid numbers of the products are specified.