KOH活化木质素制备高比表面积活性炭特性研究(英文)

Preparation and Characterization of Activated Carbons Based Alkali Lignin by KOH Chemical Activation

以木质素为制备原料,采用KOH为活化剂制备高比表面积活性炭.通过探究不同活化温度、活化剂与木质素质量比、活化时间对活性炭孔隙结构的影响,优化木质素活性炭的制备工艺.采用BET、SEM、FTIR等手段对活性炭性能进行表征.实验结果表明,最佳制备工况为KOH/木质素质量比为3∶1,活化时间1,h,活化温度为750,℃.其中,KOH/木质素质量比对焦炭孔隙结构影响最大,活化温度次之,活化时间影响最小.制备的活性炭比表面积最高可达2,684,m2/g,孔径分布以中微孔居多,表面含有—OH、—C=O等基团.

Activated carbon（AC）with high specific surface area was prepared from alkali lignin by chemical activation with KOH and its characteristics were investigated.The activation processes were conducted at various temperatures（T, 600-900 ℃）,KOH/lignin mass ratios（R,1∶1-4∶1）,activation times（t,1-3,h）.Both scanning electron micros-copy（SEM）and nitrogen adsorption isotherm as Brunauer-Emmett-Teller（BET）were used to identify the structural charac-teristics of the tested AC,and Fourier transform infrared spectroscopy（FT-IR）method was applied to analyze surface func-tional groups.Under experimental conditions,the optimum condition for preparing high specific surface AC of 2 684,m2/g was R=3∶1,T=750,℃,t=1,h.The results showed that R was the critical factor influencing the BET specific surface area compared with T and t.Pore distribution of the prepared AC mainly concentrated on micropores and mesopores.Chemical groups such as -OH and -C=O were characterized by FT-IR.