壳聚糖的改性及其絮凝性能

将壳聚糖与硫氰酸铵(NH_4CNS)和氯乙酸(CH_2ClCOOH)共热反应,制备了壳聚糖衍生物硫脲乙酸壳聚糖(NCTS)。研究了壳聚糖衍生物的投加量、不同pH值、以及电解质强度对NCTS絮凝沉降模拟地表水絮凝性能的影响。结果表明,当模拟地表水的pH为4～8、每升废水中加入150 mg改性壳聚糖时,NCTS絮凝剂对浊度的去除率最高达80%,水中电解质(NaNO_3溶液)的加入使絮凝性能有所改善,当NaNO_3质量分数为0．5%时,絮凝效果可达86．7%。

Flocculation Performance of Modified Chitosan

A kind of water-soluble chitosan derivative was prepared by the reaction of ch- itosan with NH_4 CNS and CH_2 C1COOH.The modified chitosan was used to flocculate the waste water and the effects of modified chitosan dosage pH and electrolyte on the flocculation performance were studied.The results showed that the turbidity removal rate was up to 80%.when the flocculant dosage was 150 mg·L~(-1) and pH of the simu- lant surface water varied from 4 to 8.The flocculation performance could be enhanced greatly when adding an electrolyte into the simulant surface water.It was showed that the turbidity removal rate could be 86.7% when adding 0.50% NaNO_3.