天然沸石负载壳聚糖去除废水中Cr(Ⅵ)研究

Treatment of Chromium(VI) in Wastewater by Natural Zeolite-chitosan Compound Adsorbent

将80目天然沸石与90%脱乙酰度壳聚糖的O.5%醋酸溶液按1∶1.2质量比混合,使壳聚糖负载在天然沸石上,制成固体复合吸附剂,用于去除水中Cr(Ⅵ)。最佳工艺条件是:壳聚糖与天然沸石质量比为0.04,吸附剂用量为8.0g/L,废水中Cr(VI)质量浓度不大于10mg/L,pH值为4～6,吸附平衡时间为40min,Cr(VI)去除率为80%。与活性炭吸附法相比,天然沸石-壳聚糖复合吸附剂吸附效果相近,吸附平衡时间短,成本仅为其1/6。与单一的天然沸石或壳聚糖相比,该吸附剂对Cr(VI)离子的吸附速度快、吸附能力强,成本低。

80 mesh natural zeolite was added in chitosan slurry of 90% the degree of deacetylation to prepare adsorbent which mass ratio is 1 ： 1,2.Its adsorptivity toward Cr（Ⅵ） was studied, and the optimal conditions for the Cr（Ⅵ） adsorption by it were： the mass ratio of chitosan and natural zeolite is 0.04, the dosage of the adsorbent is 8.0 g/L, the mass concentration of Cr （Ⅵ） in wastewater does not exceed 10 mg/L, the pH value is 4 - 6, the adsorption equilibrium time is about 40 mins and Cr （Ⅵ） removal efficiency is 80%. Compared with the single granular activated carbon or zeolite or chitosan, the adsorbent has a faster adsorption speed,a better adsorbability and low cost price.