载铁颗粒活性炭吸附除铬的热动力学研究

该文通过吸附动力学实验及等温吸附实验,考察了在10℃～40℃的温度条件下载铁颗粒活性炭(IOCGAC)吸附Cr(VI)的热动力学性质。结果表明:准二级反应动力学模型及Langmuir等温吸附模型可分别较好地描述IOCGAC对Cr(VI)的吸附动力学及吸附等温线实验结果(R2>0.99);吸附速率及吸附容量随温度的增加而增加。吸附速率k从0.00022增加到0.00033,吸附容量从18.48mg/g增加到23.20mg/g。根据标准吉布斯自由能变(ΔG0<0)和标准反应焓变(ΔH0>0)值判断,IOCGAC对Cr(VI)的吸附是自发的、吸热的化学吸附反应。

Thermodynamics Study of Chromium Removal by Adsorption of Iron Oxide Coated Granular Activated Carbon (IOCGAC)

Through the adsorption dynamics experiment and the isothermal adsorption experiment, the article reviews the thermodynamics character of adsorption to Cr(VI) by IOCGAC under the condition of 10℃～40℃ temperature. The result makes clear that the quasi-second reaction dynamics model and Langmuir isothermal adsorption model can separately better describe the adsorption dynamics of IOCGA to Cr (CI) and its adsorption isotherm experimental result (R2>0.99), and adsorption velocity and adsorption capacity which is increased with the raising of temperature. The adsorption velocity K increases from 0.00022 to 0.00033, and the adsorption capacity increases from 18.48 mg/g to 23.20 mg/g. Based on the typical XX free energy change (△G°< 0) and the typical reaction enthalpy change (△ H°> 0) values, it is judged that the adsorption of IOCGA to Cr (Ⅵ) is spontaneous and endothermal chemical adsorption reaction.