摘要 |
PURPOSE:To allow an anticorrosive to show an anticorrosive effect equal or superior to the effect of a nitrite inhibitor and to make the anticorrosive effective even in a high temp. range by adding a small amount of sodium nitrite to sodium silicate as the principal component. CONSTITUTION:an anticorrosive for cooling water circulating in an internal combustion engine is prepared by adding a small amount of sodium nitrite to nontoxic sodium silicate causing no environmental pollution as a principal component. In a corrosion resistance test conducted in an aqueous soln. contg. 200ppm sodium silicate and 500ppm sodium nitrite at 30 deg.C for 14 days, the degrees mdd of corrosion of mild steel, Cr-Mo cast steel, cast iron (''Tercalloy '') and brass were 0.38, 0.5, 4.61 and 0.39, respectively. |