Department of Civil and Environmental Engineering, University of Washington, Box 352700, Seattle, WA 98195, USA.
Water Res. 2010 Jul;44(14):4057-66. doi: 10.1016/j.watres.2010.05.014. Epub 2010 May 20.
This study examined effects of desalinated water on the corrosion of and metal release from copper and lead-containing materials. A jar test protocol was employed to examine metal release from copper and lead-tin coupons exposed to water chemistries with varying blending ratios of desalinated water, alkalinities, pHs and orthophosphate levels. Increasing fractions of desalinated water in the blends resulted in non-monotonic changes of copper and lead release, with generally lower metal concentrations in the presence of desalinated water, especially when its contribution increased from 80% to 100%. SEM examination showed that the increased fractions of desalinated water were associated with pronounced changes of the morphology of the corrosion scales, likely due to the influence of natural organic matter. This hypothesis was corroborated by the existence of correlations between changes of the zeta-potential of representative minerals (malachite and hydrocerussite) and metal release. For practical applications, maintaining pH at 7.8 and adding 1 mg/L orthophosphate as PO(4) were concluded to be adequate to decrease copper and lead release. Lower alkalinity of desalinated water was beneficial for blends containing 50% or more desalinated water.
本研究考察了去离子水对含铜和含铅材料腐蚀和金属释放的影响。采用罐试验方案，研究了暴露于去离子水、碱度、pH 值和正磷酸盐水平变化的混合水化学环境中的铜和铅锡合金小金属片的金属释放情况。混合水中去离子水比例的增加导致铜和铅释放出现非单调变化，去离子水存在时金属浓度通常较低，尤其是当其比例从 80%增加到 100%时。扫描电子显微镜（SEM）检查表明，去离子水比例的增加与腐蚀层形态的明显变化有关，这可能是由于天然有机物的影响。这一假设得到了代表性矿物（孔雀石和氢羟铅矿）的 ζ 电位变化与金属释放之间存在相关性的证实。对于实际应用，维持 pH 值为 7.8 并添加 1 mg/L 正磷酸盐（以 PO(4)表示）被认为足以减少铜和铅的释放。对于含有 50%或更多去离子水的混合物，较低的去离子水碱度是有益的。
