磷酸活化法制备半纤维素基颗粒活性炭

以半纤维素的主要模型物木聚糖为原料,在不添加其他粘结剂的条件下,采用磷酸活化法制备半纤维素基颗粒活性炭。讨论了浸渍比和炭活化工艺对活性炭吸附性能和孔隙结构的影响。研究结果表明:浸渍比的增加,有利于颗粒活性炭的比表面积、亚甲基蓝吸附值、强度、总孔容积和中孔容积的提高。随着炭活化温度的升高,颗粒活性炭的碘吸附值、亚甲基蓝吸附值、比表面积、总孔容积和微孔容积呈下降的趋势,强度呈上升趋势。N₂吸附-脱附等温线和孔径分析表明,颗粒活性炭具有发达的微孔结构,炭活化温度的升高不利于孔隙结构的发达。

Preparation of Hemi-cellulose-based Granular Activated Carbon by Phosphoric Acid Activation

Xylan, which is the main model compound of hemi-cellulose, was used to prepare hemi-cellulose-based granular activated carbon by phosphoric acid activation without addition any binder. The effects of impregnation ratio and carbonization/activation process on the adsorptive properties and porous texture of granular activated carbon were discussed.The result showed that specific surface area (BET),adsorption capability of methylene blue,intensity,total pore volume and mesopore volume of granular activated carbon increased with impregnation ratio increased. As the increasing of carbonization/activation temperature, the adsorption capability of iodine and methylene blue, BET, total pore volume and micropore volume of granular activated carbon were decreased,while the intensity was increased. The analysis of N₂ adsorption-desorption isotherms and pore size distribution showed that the microporous structure of granular activated carbon was developed, and the increasing of carbonization/activation temperature was not benefit for the development of porous structure.