椰壳类活性炭高温改性及吸附铝电解质熔盐中K^+的性能

High Temperature Modification on Coconut Shell Activated Carbon and Adsorptivity of the Activated Carbon for K^+ in Aluminum Electrolyte

利用SEM,ASAP2000M和FTIR对高温改性前后的椰壳活性炭的表面性能进行检测分析,并通过吸附铝电解质熔盐中K^+的实验对吸附动力学过程进行分析,研究高温改性对活性炭表面性能的影响和高温改性后活性炭吸附熔盐中K^+的性能.表面性能检测的分析结果表明,活性炭经过高温改性后比表面积由918 m^2/g提升至2 544 m^2/g,表面孔径分布得到优化,并且具有去除表面杂质的作用;同时,高温改性前后活性炭的表面官能团种类没有发生明显变化,说明高温改性后的活性炭能够在铝电解质熔盐中保持稳定的结构.吸附实验数据的分析结果表明,活性炭在铝电解质熔盐中吸附K^+的过程符合准二级动力学模型;并且,经35 min后达到吸附平衡,K^+最大吸附量为20.8 mg/g.

According to kinetic calculation of adsorption K^＋using coconut activated carbon in molten aluminum electrolyte, the modification of the surface properties and the capacity of removing potassium（ K^＋） using the high-temperature modified cocoanut activated carbon were studied,associated with the analysis of SEM,ASAP2000 Mand FTIR spectrometer. The results showed that the specific surface area changed from 918 m^2/ g to 2 544 m^2/ g after high-temperature modification and the pore size distribution of the adsorbent which exhibited the uniform mesopores were optimized. Meanwhile,the functional group species of activated carbon were not changed after high-temperature modification, which indicated that the structure of high-temperature modification activated carbon could keep stable in molten aluminum electrolyte. For the capacity of removing K^＋,it was found that the adsorption kinetics process could be described using the pseudo-second-order model and the adsorption equilibrium was reached after 35 minutes with the maximum adsorption capacity of K^＋of 20. 8 mg / g.