GB252258A - Improvements in emulsions of bituminous material - Google Patents

Abstract

252,258. Hutton, H. W., and Fulton, C. W. Feb. 23, 1925. No Patent granted (Sealing fee not paid). Emulsions, making. - Bituminous emulsions are prepared by adding separately to liquid or molten bituminous material a small proportion of a sulphonated oil or fat which has not been neutralized, even in part, and an aqueous solution of alkali or ammonia in quantity sufficient to neutralize the sulphonated product. Preferably the sulphonated oil or fat is mixed with the bituminous material and the neutralizing solution thereafter incorporated, but alternatively the neutralizing solution may be mixed with the bituminous material and the sulphonated oil or fat then added. According to an example, concentrated sulphuric acid is introduced slowly with stirring into a tank containing the oil or fat, the amount of acid being about 25 per cent by weight of the oil or fat. The temperature is kept below 80-90‹ F. during mixing, and after 5-24 hours the product is washed with a neutral salt solution or water or both and separated. The sulphonated oil or fat is incorporated with molten bitumen in the proportion of 1-5 per cent of the bitumen, and 14-28 per cent of caustic soda, reckoned on the sulphonation product, is then added in the form of a 2 per cent solution, whereafter a final addition of hot water is made. Instead of caustic soda the neutralizing agent may be ammonia or caustic potash, sodium or potassium carbonate, or the silicate or bora.te of an alkali metal or of ammonium. Specification 236,641 is referred to.