磷酸法自成型木质颗粒活性炭孔隙结构分析及其甲烷吸附性能

摘要

以杉木屑为原料,在不额外添加粘结剂的工艺下,采用磷酸活化法制备自成型颗粒活性炭,并对其活化工艺、孔隙结构和甲烷吸附性能进行了分析.结果表明:随着活化温度的升高,颗粒活性炭的吸附性能先升后降,450 ℃时吸附性能最佳,强度不断升高;浸渍比的增加有利于颗粒活性炭吸附性能的提高,不利于其强度的增大.氮气吸附等温线和压汞法分析表明:颗粒活性炭具有发达的微孔、中孔和大孔结构,浸渍比的增加有利于颗粒活性炭比孔容积的增加,不利于堆积密度和表观密度的增加.在活化温度450 ℃,压力3.4 MPa时单位质量和单位体积的颗粒活性炭的甲烷吸附值在浸渍比1.25时达到最大,分别为125.6 mL/g和115.2 L/L.%Preparation of granular activated carbon (GAC) by phosphoric acid activation from fir wood powder were analyzed without any other binder.The activation process,pore structure and methane adsorption of the synthesized GAC were also tested.The results showed that with activation temperature increasing,the adsorption capability of the GAC rose first and fell later, the abrasion strength was steadily improved and the optimum temperature was 450 ℃.With increasing of impregnation ratio,the adsorption capability of the GAC increased,however the abrasion strength decreased.The analysis of nitrogen adsorption isotherm and mercury injection method showed that the GAC possessed a large number of micropore,mesopore and macropore.The increase of impregnation ratio was favorable for the increase of pore volume, but the bulk density and apparent density decreased.The methane adsorption value of the unit mass and the unit volume of the GAC reached the maximum 125.6 mL/g and 115.2 L/L with the impregnation ratio of 1.25, activation temperature 450 ℃ and pressure 3.4 MPa.