SYNERGISTIC COMBINATION OF SODIUM SILICATE AND ORTHOPHOSPHATE FOR CORROSION CONTROL OF CARBON STEEL

摘要

PURPOSE: To control the corrosion of the surfaces of carbon steel members for various kinds of water systems by treating these carbon steel members with a specific amt. of a compsn. consisting of orthophosphate and sodium silicate. ;CONSTITUTION: The surfaces of the carbon steel members used for the cooling water systems, boiler water systems and potable water systems are heated with the corrosion suppressing compsn. consisting of about 3 wt.% orthophosphate, such as tribasic sodium phosphate, on the basis of PO₄, and about 1 wt.% sodium silicate, on the basis of SiO₂, and having a concn. of 0.1 to 100 mg/l. The corrosion of the surfaces of the carbon steel members in various kinds of the water systems which surfaces come into contact with water is suppressed by the synergistic effect of the orthophosphate and the sodium silicate. In addition, the toxic lead level in the potable water may be kept at a low level.;COPYRIGHT: (C)1993,JPO