| 摘要 |
A bitumen emulsion of the oil-in-water type is prepared by incorporating in a bitumen a minor proportion (e.g. 0.5-10 per cent. by weight) of alkali metal or ammonium soaps of naphthenic acids having an average molecular weight above 250 (preferably 300-750), incorporating in water a minor proportion (e.g. 0.5-10 per cent. by weight) of one or more water-dispersible soaps, and emulsifying the bitumen in the water. The residue obtained by distilling a petroleum lubricating oil fraction in the presence of caustic alkali may be used as the source of the naphthenic acid soaps. Soaps for addition to the water may be the same naphthenic acid soaps which are added to the bitumen or may be residues obtained by the distillation of gas oil or kerosene fractions in the presence of caustic alkali; also suitable are the ammonium or alkali metal soaps of lauric, myristic, palmitic, oleic, ricinoleic, linoleic, linolenic and abietic acids, of the fatty acids derived from tall oil, coconut oil, palm kernel oil, corn oil, cottonseed oil, sardine oil, soybean oil, and peanut oil, of acids produced by the oxidation of petroleum or paraffin wax, and of sulphonic acids and acid sulphate esters. The viscosity of the emulsion is controlled by adjusting the amount of naphthenic acid soap in the bitumen, and the demulsibility characteristics by varying the amount of soap in the water.
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