method of preventing the formation of deposits, especially kesselstein or corrosion of metal surfaces in water carrying systems. plant

摘要

Formation of deposits, esp. boiler scale, or corrosion of metal surfaces in water conduits or plant is inhibited by adding 500 ppm of a cyclic dimer of a hydroxy-diphosphonic acid. The dimer has formula (I) (where R is a 1-20C alkyl, aryl, aralkyl or aliphatic ether gp., esp. Me). (I) are esp. useful for treating (i) sea-water fed to evaporators for drinking water prodn. on ships, desert coats or islands, partic. chlorinated sea-water and sea-water subjected to continuous chlorination, and (ii) water injected into oil wells during sec. oil recovery, to inhibit the formation of Ba- or Ca-contg. deposits.