磷酸水热预处理制备高比表面积高介孔率活性炭

Preparation of mesoporous activated carbon with high specific surface area by H_3PO_4 hydrothermal pretreatment

以锯末为原材料,采用磷酸水热预处理后活化的工艺制备高介孔率活性炭,以比表面积和孔容为评价标准,通过单因素实验探究了酸料比、活化温度、活化时间对活性炭比表面积及总孔容的影响规律,验证了该工艺的可行性.最优条件下所制备的活性炭比表面积为2579 m^2·g^(-1),介孔率达到96.6%,充分说明磷酸水热预处理工艺能够显著提高活性炭介孔孔容占比.亚甲基蓝(MB)吸附实验数据与Redlich-Peterson模型拟合度较好,样本活性炭对MB的吸附为单分子层吸附,最大单层吸附量为618.35 mg·g^(-1),接近于实验测试值632.79 mg·g^(-1),表明该方法制备的活性炭具有良好的MB吸附性能.

The highly mesoporous activated carbon was prepared from sawdust treated by hydrothermal process in H3PO4 environment. The influence of H3PO4/sawdust mass ratio, activation temperature and time on surface area and total pore volume were investigated through the single factor experiments. The activated carbon with the highest surface area of 2579 m2· g-1 was obtained on the optimized condition. Particularly, the mesoporous ratio of the optimized sample exceeds 96%. The MB adsorption is fitted well with the Redlich-Peterson model, which means the single-layer adsorption predominate the adsorptive behavior. The maximum single-layer adsorption capacity （618.35 mga2 g-1 ） closes to the experimental result 632.79 mg· g-1, indicating the sample has excellent MB adsorption capacity.