聚乙烯亚胺基黄原酸钠与铁盐共同处理低浊水

以聚乙烯亚胺（PEI）为母体，通过化学反应将二硫代羧基引入到其分子链中，制备出新型高分子絮凝剂聚乙烯亚胺基黄原酸钠（PEX），采用低浊水样作为考察对象，通过絮凝实验研究PEX分别与Fe （Ⅱ）盐、Fe （Ⅲ）盐对水样中浊度的去除性能.结果表明，PEX单独处理低浊水时，水样的初始浊度和pH值对PEX除浊效果均有一定的影响，除浊效率随着初始浊度的降低而降低，随着pH值的升高而先升高后降低；当初始pH值位于PEX等电点附近时，浊度的去除率可达到最高，初始浊度为10.0，15.0，30.0NTU，浊度的去除率分别为88.46%，91.17%，92.73%.PEX与Fe盐共同除浊时浊度的去除率随着体系pH值的升高先升高后降低，投加Fe （Ⅲ）盐后浊度的去除效果总体上优于投加Fe （Ⅱ）盐后的效果.PEX与Fe盐共同除浊和PEX单独除浊时的絮凝作用机理不尽一致，Fe盐的加入可起到一定的电中和作用.

Treatment of low-turbidity water by polyethyleneimine-sodium xanthogenate and ferrous/ferric salts

A novel macromolecule flocculant polyethyleneimine-sodium xanthogenate (PEX) was prepared by chemical reaction to graft dithiocarboxylic groups onto polyethyleneimine (PEI). The removal performance of turbidity by PEX and ferrous/ferric salts from water samples containing low turbidity was studied by using flocculation experiments. The initial turbidity and pH value had a certain effect on the removal properties of turbidity by only using PEX. The removal efficiency of turbidity decreased with the decrease of the initial turbidity of water samples, and increased at first and then decreased with the increase of pH value. When the initial pH value of the water samples approached the isoelectric point of PEX, the removal rate of turbidity was highest, and reached 88.46%, 91.17% and 92.73% at the original turbidity of 10.0, 15.0 and 30.0NTU for the water samples, respectively. The removal rate of turbidity increased at first and then decreased with the increase of pH value after the addition of PEX and ferrous/ferric salts, and the removal efficiency of turbidity was better with ferric salts than ferrous salts. The flocculation mechanism when adding only PEX was different from the one when adding both PEX and ferrous/ferric salts, and ferrous/ferric salts played a main role of charge neutralization in the flocculation process.