微波活化玉米秸秆生物质炭对水中亚甲基蓝的吸附研究

Study on the Adsorption of Maize Straw Biochar Activated by a Microwave to Methylene Blue in Water

本文以浓H3PO4为活化剂,通过微波活化法处理玉米秸秆,制备生物质炭,并通过正交试验寻找最佳的制备条件,确定浸渍比1:1,预炭化时间6 h,微波活化时间5 min时,对亚甲基蓝的吸附量最大。在静态吸附实验表明:生物质炭对亚甲基蓝的最大吸附量为84.89 mg·g^-1,吸附过程符合Langmuir等温吸附式和准二级动力学方程,为单分子层吸附和快速吸附。在吸附机理研究中,发现膜扩散控制吸附速率。

Maize straw was activated with concentrated phosphoric acid and the biochar was prepared by microwave activation method.The optimum preparation conditions were determined by orthogonal test.It was found that the largest adsorption capacity of biochar on methylene blue was 84.89 mg·g^-1 when the impregnation ratio was 1:1,the precarbonization time was 6 h,and the microwave activation time was 5 min.The adsorption process of methylene blue could be better described by the Langmuir isothermal ad the pseudo-second-order model,which indicated that the adsorption process could be considered as monolayer adsorption and rapid adsorption.The research on the adsorption mechanism showed that the adsorption rate was controlled by the membrane diffusion.