施氏矿物对废水中锑的吸附:性能及腐植酸的影响

Adsorption of Antimony by Schwertmannite: Capability and Effect of Humic Acid

本文通过化学方法水解制备施氏矿物,研究其对于Sb(Ⅲ)和Sb(Ⅴ)的吸附性能,以及腐植酸的存在对于其吸附过程的影响。研究结果表明:施氏矿物对Sb(Ⅲ)和Sb(Ⅴ)均有很强的吸附能力,且Sb(Ⅲ)>Sb(Ⅴ),同时吸附速率都很快;施氏矿物对Sb(Ⅲ)和Sb(Ⅴ)的吸附符合Langmuir吸附模型;施氏矿物对Sb(Ⅲ)和Sb(Ⅴ)的吸附行为受pH影响不大;在Sb(Ⅲ)和Sb(Ⅴ)的起始浓度较低的情况下,腐植酸对于施氏矿物的吸附量影响不是很明显。对于施氏矿物吸附Sb(Ⅲ)的过程,先投加施氏矿物,吸附完成后再投加腐植酸会时吸附量降低,随起始浓度增加,这种影响也越来越明显。相同的情况也出现在施氏矿物对Sb(Ⅴ)的吸附过程中。

Schwertmannite made in a chemical way was kept suspending in the water. Then it was studied on the adsorption of Sb（Ⅲ） and Sb（Ⅴ） on schwertmannite and the effect of humic acid. The result shows that schwetmannite has a strong ability on adsoption of Sb（Ⅲ） and Sb（Ⅴ）. And the adsorption is very fast for equilibrium is reached within 10 minutes. The equilibrium adsorption amount of Sb（Ⅲ） is more than that of Sb（Ⅴ）. The adsorption isotherm experimental data fit the Langmuir isotherm model better than the Freundlich. The adsorption of the antimony belongs to the monolayer adsorption. pH has little effect on the adsorption, the acid environment contribute a little to the adsorption. The effect of the adding sequence of humic acid is not obvious in the case of lower initial concentration. But as the initial concentration goes up, the effect becomes obvious. The equilibrium adsorption amount of the following methods are almost the same. The first method is only add schwertmannite into the Sb（Ⅲ） solution, the second is add schwertmannite and humic acid into the Sb（Ⅲ） at the same time and the last method is add Sb（Ⅲ） solution into the balanced solution of schwertmannite and humic acid. However the equilibrium adsorption amount of schwertmannite drop down in the case of adding humic acid into the balanced solution of schwertmannite and Sb（Ⅲ）. As the initial concentration goes up, this appearance becomes more and more obvious. The same appearance occurs in the adsorption of Sb（Ⅴ） on schwertmannite.