硝酸改性稻秆处理含Pb^(2+)模拟废水

Treatment of Pb(Ⅱ) ion in simulated wastewater by rice straw modified by nitric acid

在150 m L溶液中,稻秆用量为5 g,硝酸浓度为10%,稻秆颗粒度为20目,改性温度为80℃,改性时间为3h,制备得到硝酸改性稻秆吸附剂。详细探讨了用该吸附剂处理含Pb^(2+)废水的影响因素:吸附剂用量、Pb^(2+)初始浓度、溶液pH值、吸附时间和吸附温度等对Pb^(2+)吸附率的影响,并进一步通过正交实验及对比实验得出处理200 m L,初始浓度为300mg·L-1的含Pb^(2+)废水的最佳吸附工艺为:吸附剂用量为4 g,pH值为6,吸附时间为3 h,吸附温度为20℃,在此工艺条件下,对Pb^(2+)的吸附率达到94.31%,吸附量为14.15 mg·g^(-1)。

In this study,rice straw modified by nitric acid was synthesized under the conditions that the volume of 10% nitric acid solution was 150 m L,rice straw dosage was 5 g,particle size of rice straw was 20 mesh,modification time was 3 h,modification temperature was 80 ℃. Some factors,such as sorbent dosage,Pb（ Ⅱ） ion concentration,pH,adsorptiontime,adsorption temperature which affect the adsorption rate of Pb（ Ⅱ） ion,were investigated. The adsorption technics were more optimized through orthogoral experiment and comparative experiment. When the volume of Pb（ Ⅱ） ion simulated wastewater was 200 m L,Pb（ Ⅱ） ion concentration was 300mg·L-1,the best adsorption technics were as follows： a sorbent dosage of 4 g,a pH of 6,an adsorption time of3 h,and adsorption temperature of 20 ℃. Under those conditions,the adsorption rate of Pb（ Ⅱ） ion was94. 31% and the adsorption capacity of sorbent was 14. 15 mg·g-1.