甘草是中药药方的主要组成部分，随着中药产业发展，甘草渣的产量逐渐增加，但对甘草渣的利用并不理想。甘草中含有大量纤维素、半纤维素以及木质素，是制备活性炭的优良原料。采用水热炭化-化学活化联合制备活性炭的技术路线，可对含水量高的甘草渣进行预处理，通过化学活化制得活性炭，是甘草渣高效利用的优良途径。以甘草为原料，将甘草与去离子水以质量比1∶8混合后分别在210、240、270、300 ℃下进行水热炭化，并将270 ℃下水热炭化反应所得水热炭分别用不同化学活化剂、在不同活化温度下进行活化。结果表明，样品在270 ℃时出现明显的官能团变化，认为在270 ℃时发生了炭化；采用水热炭化-化学活化联合制备的活性炭均具有较好的孔隙结构，其中KOH作为化学活化剂、活化温度为700 ℃条件下所制备活性炭比表面积为1 605.77 m2/g，总孔容为0.890 4 cm3/g，平均孔径为2.218 0 nm，甲基橙吸附量为184.5 mg/g。

Licorice is the main component of traditional Chinese medicine prescriptions, and the amount of licorice residue produced has gradually increased with the development of the traditional Chinese medicine industry. However, the utilization of licorice residue is not ideal. Licorice contains a large amount of cellulose, hemicellulose and lignin, which is an excellent raw material for the preparation of activated carbon. The technical route of combined hydrothermal carbonization and chemical activation to prepare activated carbon can better pretreat the licorice residue with high water content, and conduct chemical activation to prepare activated carbon, which is an excellent way for efficient utilization of licorice residue. Using licorice as raw material, licorice was mixed with deionized water at a mass ratio of a ratio of 1∶8, and then hydrothermally carbonized at 210, 240, 270, and 300 ℃ respectively.And the hydrothermal carbon obtained by the hydrothermal carbonization reaction at 270 ℃ was activated with different chemical activators and at different activation temperatures, respectively. The results show that the sample has obvious functional group changes at 270 ℃, and it is believed that carbonization has occurred at 270 ℃. The activated carbon prepared by the combination of hydrothermal carbonization and chemical activation has a good pore structure.With KOH as a chemical activator,the activated carbon prepared under the condition of activation temperature of 700 ℃ has a specific surface area of 1 605.77 m2/g, a total pore volume of 0.890 4 cm3/g, an average pore size of 2.218 0 nm, and a methyl orange adsorption capacity of 184.5 mg/g.

0 引言

1 试验

   1.1 试验材料

   1.2 试验装置及方法

   1.3 样品分析

2 结果与讨论

   2.1 水热炭官能团结构分析

   2.2 活性炭比表面积及孔隙分析

   2.3 活性炭微观形貌分析

   2.4 吸附特性

   2.5 水热-KOH活化机制分析

3 结论