软水中富里酸对铜管/磷酸盐体系溶解性铜释放影响

Influence of fulvic acid on soluble copper release in soft water from copper pipe/phosphate system.

通过静态模拟试验研究了在软水体系中富里酸对铜管/磷酸盐缓蚀行为的影响,结果表明,富里酸含量、软水pH值、停留时间影响磷酸盐对铜管的缓蚀作用;高浓度的富里酸(16mg/L,以TOC计)明显增加溶解性铜释放,且从新铜管释放溶解性铜浓度高于老化6个月和12个月的铜管;在富里酸存在下,pH值较低时显著增加溶解性铜的释放,随着pH值的增大,富里酸对溶解性铜的释放影响降低;在96h的停留过程中,溶解性铜的释放浓度不断发生变化,表明富里酸与铜离子形成的络合物影响磷酸与铜的相互作用,从而影响磷酸盐对铜管的缓蚀效果.

The effects of fulvic acid on copper/orthophosphate corrosion inhibition behavior in soft water system were studied. The doses of fulvic acid, pH values of soft water and stagnation times affected the function of phosphate corrosion inhibition for copper pipe. Fulvic acid of high concentration (16mg/L as TOC) enhanced markedly the soluble copper release. The soluble copper release concentration from new copper pipe was higher than that from pipes aging 6 and 10 months. In the presence of fulvic acid, when the pH value was relatively low, the release of soluble copper increased; and the influence of fulvic acid on this release decreased with raising of pH value. In the 96h, stagnation process, the concentration of this release changed increasingly, indicating that the complex compound of fulvic acid and copper ion influenced the interaction of phosphoric acid and copper; thus influenced the corrosion inhibiting effect of phosphate on the copper pipe.