沸石负载接枝改性壳聚糖复合净水剂去除污水COD的研究

The Research for Graft Modification Chitosan Supported by Permutite and Its Removal of COD in Waste Water

以生活污水为处理对象,通过对沸石、酸改性沸石、聚合氯化铝(PAC)改性后的沸石、沸石负载接枝改性壳聚糖复合净水剂进行COD去除对比试验.实验结果表明:沸石负载改性壳聚糖复合净水剂对COD有较高的去除率,对于COD浓度为400 mg·L-1的污水,在温度为25℃的条件下,经2 h搅拌接触,COD浓度可降至78 mg·L-1,去除率可达81%.SEM结果表明:壳聚糖部分包覆在沸石上,沸石负载接枝改性壳聚糖复合净水剂对COD的去除机理是复合净水剂表面(及内部孔隙)吸附作用和离子交换作用.对于普通自来水厂,只需将快滤池中常用的石英砂部分替换成沸石负载接枝改性壳聚糖复合净水剂即可有效去除水中的COD.

High concentration of COD in waste water is extremely harmful to human health. How to remove COD ef-ficiently and at low-cost in tap water has been a tough problem for numerous water plants. In this study,experiments were conducted using waste water to investigate the effect upon the COD removal test by Permutite modification with acid and PAC、graft modification Chitosan Supported by Permutite. The results show that graft modification Chitosan Supported by Permutite has better removal efficiency. Under the condition of temperature of 25 ℃,contact time for 2 h,the COD concentration in source water is decreased from 400 mg·L-1 to 78 mg·L-1 ,while the removal rate comes up to 81%. SEM indicated that CTS partially loaded on permutite. Loading number increased with m（ CTS）/m（ permut ite）. The mechanism of removing COD by modified permutite is permutite surface（ and internal pore）ad-sorption and ion exchange. Using modified permutite partially to replace the common quartz sand in fast filer is only needed for ordinary water plants to remove COD effectively in water.