method for preventing corrosion and deposits on circulating water in contact with the metal pipes and other metal parts

摘要

Partial esters of hydroxy-polycarboxylic acids having at least one unesterified carboxyl group and at least one other carboxyl group esterified with an alcohol having one to 20 repeating oxyalkylene groups and a terminal hydrocarbon radical are useful as additives for inhibiting corrosion and scale on metal parts in a circulating water system. Especially suitable for the use are alkyl polyoxyethylene alcohol partial esters of citric, malic and tartaric acids. Preparation and use of several preferred partial esters of the class are detailed.