硫酸改性核桃壳处理含Cr(Ⅵ)模拟废水研究

Treatment of Cr (Ⅵ) Ion in Simulated Wastewater by Walnut Shell Modified by Sulfuric Acid

在100 mL 8 mol·L^(-1)硫酸溶液中,核桃壳加入量为9 g,核桃壳颗粒度为100目,反应时间为3 h,反应温度为25℃的条件下制备得到硫酸改性核桃壳。硫酸改性核桃壳对Cr(Ⅵ)具有优异的吸附性能。详细探讨了硫酸改性核桃壳处理含Cr(Ⅵ)模拟废水的影响因素:废水pH值、Cr(Ⅵ)离子浓度、硫酸改性核桃壳用量、处理时间和处理温度等对Cr(Ⅵ)去除率的影响,并进一步通过正交试验及对比试验得出处理150 mL 200 mg·L^(-1)的含Cr(Ⅵ)模拟废水的最适宜处理工艺为:pH值为1,硫酸改性核桃壳用量为1.4 g,处理时间为2 h,处理温度为25℃,在此条件下,对Cr(Ⅵ)的去除率达到95.86%,Cr(Ⅵ)吸附量为20.54 mg·g^(-1)。

Walnut shell modified by sulfuric acid was synthesized under the conditions that the volume of 8 mol·L^(-1) sulfuric acid solution is 100 mL,walnut shell dosage is 9 g,particle size of walnut shell is 80 mesh,reaction time is 3 h,reaction temperature is 25 ℃. Walnut shell modified by sulfuric acid has excellent adsorption property to Cr (Ⅵ) ion. Some factors,such as the dosage of walnut shell modified by sulfuric acid,Cr (Ⅵ) ion concentration,pH,treatment time,treatment temperature which affect the removal rate of Cr (Ⅵ) ion,were investigated. The dispose technics were more optimized through orthogonal experiment and comparative experiment. When the volume of Cr (Ⅵ) ion simulated wastewater is 150 mL,Cr (Ⅵ) ion concentration is 200 mg·L^(-1),the best dispose technics are as follows: pH= 1,the dosage of walnut shell modified by sulfuric acid is 1. 4 g,treatment time is 3 h,treatment temperature is 25 ℃. Under those conditions,the removal rate of Cr (Ⅵ) ion was 95. 86% and the adsorption capacity of sorbent was 20. 54 mg·g^(-1).