功能化火山石对重金属废水中Cu^(2+)吸附性能研究

Study on Adsorption of Cu^(2+) Ion from Heavy Metals Wastewater by Functionalized Volcanic Rocks

通过对火山石进行热处理和强酸强碱改性,得到了性能优良的火山石吸附材料。利用SEM、BET对三种火山石进行结构表征,并探讨了pH、离子强度、吸附时间、初始浓度对改性火山石去除铜离子废水吸附效果的影响。强酸强碱改性火山石的吸附性能最为优异,在pH=5、无机盐浓度为20 mmol/L条件下,吸附150 min可达到饱和状态,吸附量可达0. 35 mmol/g。等温吸附行为符合Langmuir和Freundlich吸附模型,且Langmuir等温吸附模型的拟合效果更好;动力学吸附行为更符合准二级动力学模型,主要表现为离子交换过程。

Through the modification of volcanoes with heating or strong acid/alkali, volcano adsorption materials capable of removing heavy metal ions efficiently were obtained. The structures of volcanoes with or without modification were characterized by BET and SEM, and effects of initial concentration, pH, ionic strength and adsorption time on the removal of Cu^2+ were investigated. The volcanoes treated with strong acid/alkali presented the best adsorption performance, and the adsorption capacity attained to 0.35 mmol/g at pH=5 and CNaNO 3=20 mmol/L, also the saturated adsorption can be reached in 150 min. The isothermal adsorption behavior can be well described by Langmuir and Freundlich adsorption models, and Langmuir isothermal adsorption model fitted better. The kinetic adsorption behavior agreed better with the quasi-second-order kinetic model than quasi-one-order kinetic model, which indicated that it was mainly controlled by a chemical adsorption process.