超声波辅助法制备纳米FeS处理酸性含铬废水工艺研究

Study on the preparation of nano-FeS by ultrasonic assisted method for the treatment of acidic chromium-containing wasterwater

针对排放酸性含铬废水所产生的环境污染问题,采用超声波辅助法制备纳米FeS,用于处理酸性含铬废水。通过正交试验确定了超声波辅助法制备纳米FeS的最佳制备条件,并讨论了反应时间、pH值和Cr(Ⅵ)初始浓度对纳米FeS处理酸性含铬废水的影响。结果表明:超声波辅助法制备纳米FeS的最佳制备条件为超声波频率40k Hz、超声波处理时间10 min、制备反应温度15℃,在此条件下Cr(Ⅵ)和总铬的去除率分别为81.03%、63.40%;当反应时间达到50 min后,纳米FeS对酸性含铬废水的处理效果趋于稳定,酸性条件能促进纳米FeS对Cr(Ⅵ)和总铬的去除;随着Cr(Ⅵ)初始浓度的升高,纳米FeS对Cr(Ⅵ)和总铬的单位去除量逐渐增大,当Cr(Ⅵ)初始浓度为300 mg/L时,Cr(Ⅵ)和总铬的单位去除量分别可达486.65和383.55 mg/g。可见,超声波制备的纳米FeS可以有效去除废水中的铬离子,为今后实际工程应用提供了一定的理论指导。

In view of the environmental pollution caused by the discharge of acidic chromium-containing wastewater,nano-FeS was prepared by ultrasonic assisted method for the treatment of this kind of wastewater. The optimum preparation conditions of nano-FeS were determined by orthogonal test,and the effect of reaction time,pH and initial concentration of Cr( Ⅵ) on the treatment of acidic chromium-containing wastewater by nano-FeS was discussed. The results show that the optimum preparation conditions for the preparation of nano-FeS by ultrasonic assisted method are as follows: ultrasonic frequency 40 k Hz,ultrasonic treatment time 10 min,preparation reaction temperature 15 ℃ . Under these conditions,the removal rate of Cr( Ⅵ) and total chromium is 81. 03% and 63. 40%,respectively. When the reaction time reaches 50 min,the treatment effect of nano-FeS on acidic chromium-containing wastewater tends to stabilize. Acidic conditions can facilitate the removal of Cr( Ⅵ) and total chromium by nano-FeS,as the initial concentration of Cr( Ⅵ) increases,the unit removal rate of Cr( Ⅵ) and total chromium by nano-FeS gradually increases. When the initial concentration of Cr( Ⅵ) is 300 mg/L,the unit removal rate of Cr( Ⅵ) and total chromium can reach 486. 65 mg/g and 383. 55 mg/g. It is found that the nano-FeS prepared by ultrasonic can effectively remove chromium ions from wastewater,which provides some theoretical guidance for practical engineering applications in the future.