Abstract: A method for manufacturing casting molds or mold cores comprising shaping an aqueous mixture of sand, binder, a hydrocarbon resinous material and a porous, heat-resistant inorganic material.
Type:
Grant
Filed:
April 11, 1977
Date of Patent:
November 13, 1979
Assignees:
AB Nynas-Petroleum, AB Westin and Backlund
Abstract: A mixture of petroleum acids can effectively be separated from a petroleum distillate containing such a mixture by adjusting the molecular weight distribution of the petroleum acids in the mixture so that at least 10% of the acids have a molecular weight of less than 260 and at least 50% of the acids have a molecular weight of more than 260, treating the petroleum distillate with an aqueous solution of sodium hydroxide which solution is added with at least 5% of a sodium salt, calculated on the weight of the aqueous solution, at a temperature of at least 85.degree. C in one or more reactors to the formation of a reaction mixture containing three phases and causing said three phases to separate.