核桃壳化学-物理耦合活化法制备活性炭及其表征

采用植物废弃物核桃壳为原料,以化学-物理耦合活化法制备了核桃壳活性炭,考察了磷酸浓度、活化温度、活化时间对核桃壳活性炭碘值、亚甲基蓝吸附值和烧失率的影响。结果表明,最佳制备条件为:磷酸质量分数85%,活化温度900℃,活化时间3h。在此制备条件下,核桃壳活性炭的比表面积为1 241.81m2·g-1,吸附累积总孔容为0.90cm3·g-1,最可几孔径分布为1.62nm。采用扫描电子显微镜、透射电子显微镜、比表面积测定仪以及红外光谱仪对核桃壳活性炭的表面形貌、孔结构及表面官能团进行了分析。

Preparation and Characterization of Activated Carbon from Walnut Shell by Coupled Physiochemical Activation

Activated carbons were prepared by phosphoric acid activation combined with carbon dioxide activation from plant waste walnut shell.The effects of phosphoric acid concentration,activation temperature and activation time on iodine value,methylene blue adsorption value and burn-off were investigated in detail.The optimal activation conditions are determined as: phosphoric acid concentration 50%,activation temperature 900 ℃,activation time 3 h,under which a specific surface of 1 241.81 m2·g-1,adsorption cumulative pore volume of 0.90 cm3·g-1,the most probable pore size of 1.62 nm could be reached.The surface morphology,structure of pore and surface functional groups of the prepared activated carbon were characterized with scan electric microscope,transmission electron microscope,surface area and porosity analyzer,and FT-IR spectra,respectively.