摘要
以稻壳为原料,在550?C,氮气气氛下热解制备生物炭(RHBC),通过吸附热力学及动力学实验,考察稻壳生物炭对稀土元素Ce、Y的吸附特性。吸附热力学实验结果表明,RHBC对Ce、Y的吸附行为符合Langmuir模型,对Ce、Y的最大吸附量分别为19.80 mg?kg?1、8.61 mg?kg?1。动力学结果表明,RHBC对Ce、Y的吸附动力学过程符合Lagergren二级动力学模型, 吸附过程倾向于化学吸附。反应体系pH在3~7时,RHBC对Y的吸附效率随着pH的增大而增大,RHBC对Ce的吸附效率受溶液pH影响较小,pH3~7吸附效率均达到96%以上。
The rice husk biochar (RHBC) was prepared with rice husk by pyrolysis at 550?C under nitrogen atmosphere. Adsorption isotherm and kinetics study were investigated to determine the adsorp-tion capacities of rare earth element Ce, Y onto RHBC in solution. The adsorption results showed that the adsorption isotherm of Ce, Y onto rice husk biochar could be well described by Langmuir model, and the maximum adsorption capacities were 19.80 mg?kg?1 of Ce, and 8.61 mg?kg?1 of Y. The kinetics results showed that the adsorption process could be well fitted by Lagergren pseudo-second-order model, for a chemical adsorption process. In addition, in the solution pH range of 3 - 7, the removal rate of Y on RHBC enhanced significantly with the increasing pH, while the solution pH made a negligible effect on the removal rate of Ce onto RHBC, which were higher than 96%.
出处
《化学工程与技术》
2017年第5期188-198,共11页
Hans Journal of Chemical Engineering and Technology