活性炭酸碱预处理最佳方案确定及性能表征

Characterization of activated carbon from acid-alkali pretreatment and determine the preferred plan

以普通市售活性炭为原料,采用正交试验法确定酸碱预处理的最佳方案.通过BET、SEM、FTIR以及碘吸附值分析活性炭微孔结构、表面形貌、官能团及吸附性能的变化.结果表明,酸碱预处理的最佳方案为:KOH的质量分数4%,煮沸时间2h,HF的质量分数5%,HF煮沸时间0.5h.在该条件下处理的活性炭比表面积为1 320m^2·g^(-1)比原样提高了26.4%,碘吸附值为1 272.0mg·g^(-1)比原样提升了14.9%;预处理后的活性炭表面及孔隙变得干净光滑,总孔容变大,微孔体积增大.酸碱预处理能使活性炭表面酸性含氧官能团增加,吸附性能提高.

Ordinary commercial activate carbon is tested by orthogonal experimental to determine the preferred plan. The morphology structure and functional groups and absorption property of active carbon were observed by BET,SEM,FTIR and iodine number. The results show the optimum conditions are that the mass fraction of KOH 4 % , boiling time 2 h;the mass fraction of HF 5% , boiling time 0. 5 h. The result of the surface area is 1 320 m^2· g^-1 improved of 14. 9% ; iodine adsorption value is 1 272. 0 mg·g^-1 improved of 14. 9 % ; the surface of the activated carbon becomes smooth and clean, pore structure turn uniformity; themicropore volume becomes bigger ; after acid-alkaii pretreatment the acid oxygen functional groups increased in activated carbon surface,absorption property is improved.