摘要:
在无外加电压条件下研究了颗粒物对阳离子交换膜分离去除铜离子效果的影响。选用硅酸、二氧化硅、氧化铝和水杨酸等4种物质作为颗粒物分别进行实验，其添加量均为50 mg/L。Cu2+及其补偿离子K+的浓度分别为0.0787 mmol/L(5 mg/L)和0.787 mmol/L，水温为25±1℃，搅拌强度为600 r/min，水力停留时间为12 h。在所述实验条件下运行96 h后,水中无颗粒物干扰时，铜离子去除率为84%；水中存在带负电荷颗粒物（硅酸）和不带电荷颗粒物（二氧化硅和氧化铝）时，铜离子去除率略为下降至81%；而当水中存在带正电荷颗粒物（水杨酸）时，铜离子的去除率进一步下降为79%。研究结果表明带正电荷颗粒物对铜离子的交换去除影响较带负电荷或不带电荷颗粒物大，因为带正电荷颗粒物更易迁移至阳离子交换膜表面甚至进入膜内，并与膜表或膜内离子交换基团结合，从而导致铜离子交换去除明显下降。
Abstract:
Four particle materials, silicon acid, silicon dioxide, alumina, and salicylic acid were selected and all were dosed at 50 mg/L separately. The concentrations for Cu2+ and its compensating ion, K+, were at 0.0787 mmol/L(5 mg/L)and 0.787 mmol/L, respectively, the water temperature was controlled at 25±1℃, the mixing intensity was set up at 600 r/min, and the hydraulic retention time was 12 h. After 96 h operation under those conditions, the removal efficiency of Cu2+ was 84% when there was no disturbing particle; and the removal efficiency of Cu2+ slightly decreased to 81% when the negatively charged particles (silicon acid) or neutral particles (silicon dioxide and alumina) were present; further, it was found that the removal efficiency of Cu2+ decreased to 79% when positively charged particles (salicylic) were dosed. These results indicate that particles with positive charge imposed more effects on the Cu2+ removal than those with negative or non charge, for the positively charged particles could come to the membrane surface or even enter the membrane and combine with the ionic exchanging groups easier than the other particles, resulting in the Cu2+ removal decreasing more.
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