Patent ID: 7244372
Filing Date: 2007-07-17
Classification: C09K,C23F

Abstract:
1. A method for making a cooling fluid for engines, comprising the following steps: a) mixing 1-10 parts of sodium phosphate, 1-10 parts of sodium borate, 1-5 parts of benzotriazole, 1-10 parts of sodium benzoate and 80% of 800-1400 parts of deionized water with stirring, until dissolved completely; b) adding to the solution formed in step a) 1-5 parts of citric acid with stirring until all said citric acid is dissolved completely; c) separately mixing 1-5 parts of 2-mercaptobenzothiazole, 10% of 800-1400 parts of deionized water, and 1-5 parts of sodium hydroxide with stirring, heating to boiling point, and then adding to b) while still hot; d) adding 1-3 parts of a silicate stabilizing agent over 30 minutes with stirring, adjusting the pH to pH 8-9 by adding sodium hydroxide; e) separately mixing 1-3 parts of sodium silicate and 10% of 800-1400 parts of deionized water with stirring until said sodium silicate is dissolved, then adding to d) over 30 minutes with stirring; and adjusting the pH with sodium hydroxide to a pH of 10-11, until homogeneous; and f) adding 600-1200 parts of ethylene glycol, 0.1-0.3 parts of a defoaming agent, and 0.1-0.3 parts of a dye with stirring until homogeneous.