采用物理吸附、光催化及化学絮凝三种方法对宜昌一化工有限公司湿法制磷酸中含AS废水(砷含量为13.56Mg/l)进行了消减研究,三种方法中:物理吸附法活性炭的饱和吸附含量是1.0 g/50Ml,此时废水84.4%的AS被吸附除去,黏土的吸附试验中未发现吸附饱和现象;化学氧化法中,fEnTOn试剂最佳浓度比为[H2O2]∶[fE3+]=200∶1,此时可以将82.2%的AS3+氧化为低毒的AS5+;化学絮凝法中,絮凝剂-96、絮凝剂-98及硅藻土三种絮凝剂作用的最佳PH分别为12.6、12.6、11.8,絮凝剂的最佳用量分别为10、9、13.0 Mg/Ml对废水中AS3+转化率分别为65.7%、73.2%、76.3%.设计了含AS废水处理装置,经处理后废水中AS的含量达到国家工业废水排放标准.Physical absorption,photocatalysis and chemical flocculation methods were used to investigate the degradation of arsenic(about 13.56 mg / L) in wastewater of wet-process phosphoric acid from a Chemical Co.,Ltd in Yichang,China.The results showed that the absorption capacity of activated carbon was 1g /50 mL and 84.4% arsenic could be absorbed efficiently,while the clay could not reach the saturated adsorption in the physical absorption.As3 +was oxidized to lower poisonous As5 +by Fenton reagent and the removal rate reached 82.2% at the optimum parameter [H2O2]∶ [Fe3 +]=200∶ 1 using the photocatalysis method.As to the method of chemical flocculation,the optimum conditions of flocculant-96,flocculant-98,flocculant-diatomite were as follows:the optimum pH was 12.6,12.6,11.8,the optimum quantity of flocculant was 10,9,13 mg / mL and the removal rate of As3 +was 65.7%,73.2%,76.3%,respectively.At last,an experimental device was designed to degradate arsenic in wastewater from Wet-process phosphoric acid and the concentration of As3 +in the treated wastewater could meet the state standard for discharging of industry wastewater.国家自然科学基金项目(21177072;21207079
