壳聚糖水处理剂对含Cr^(3+)废水的处理

Biosorption of chromium(Ⅲ) from solution by chitosan biosorbent

研究了壳聚糖水处理剂对Cr3+的吸附特性 ,考察了 pH、水处理剂粒度、Cr3+浓度等因素的影响 ,最佳pH范围为 4 5～ 5 5,粒度以 2 0 0～ 30 0 μm之间为优 ,吸附模型与Langmuir方程符合得很好 ,饱和吸附容量可达75 2 3mg/g。在此基础上采用固定床形式 (D1 6mm× 1 0 0mm)对北京市皮革厂鞣革废水进行了处理 ,出水浓度低于 1 5mg/L ,动态吸附容量可达 2 3 76mg/g ,壳聚糖水处理剂可以反复使用 5次以上。

A new product called “chitosan biosorbent” is used to remove chromium (Ⅲ) from solution. The effects of pH, biosorbent particle size and initial chromium(Ⅲ) concentration are studied. It shows that pH 4.5 ～5.5 is the optimal range of absorption. Biosorbent particle size with 200～300 μm has better results. The adsorption isotherms could be described by Langmuir model. The maximum adsorption capacity could reach 75.12 mg/g biosorbent. A packed column ( D 16 mm×100 mm) is used to test its possible application in tannery wastewater treatment. Under the optimal condition, the column could work well. The chromium(Ⅲ) concentration in the discharge water could be reduced from 2 000 mg/L to 1.5 mg/L, the maximum adsorption capacity could reach 23.76 mg/g chitosan biosorbent and the column could be used for more than 5 times.