Abstract:

The physicochemical properties of wheat stalk biochars(XM300, XM450, XM600) were characterized by pore size and specific surface area analyzer, SEM, FTIR and Boehm titration, respectively. Then the adsorption mechanism of norfloxacin(NOR) on biochars were investigated. The results showed that the specific surface area and pore volume of biochars increased with increasing the pyrolysis temperature, while the pore size and the amounts of acidic groups such as carboxylic, lactone and phenolic hydroxyl groups decreased. The pseudo-second-order kinetics equation and Langmuir model were more suitable to describe the adsorption of NOR on biochars. The fitting results of Intra-particle diffusion model showed that there were two separate stages in sorption process:fast external diffusion and slow inter-particle diffusion. The XM300 had the highest adsorption capacity of 40.30 mg/g, which was mainly attributed to that the non-carbonized organic matter in the low pyrolysis biochar can capture norfloxacin in the manner of partition.

Key words: biochar, norfloxacin, wheat stalk, adsorption, partition

摘要：

采用孔径与比表面积分析仪、SEM、FTIR及Boehm滴定对小麦秸秆生物炭（XM300、XM450、XM600）进行表征，考察了生物炭对诺氟沙星（NOR）的吸附机制。结果表明，随着热解温度的升高，生物炭比表面积与孔容积增大，孔径变小，表面羧基、内酯基与酚羟基等酸性官能团数量减少。伪二级动力学方程和Langmuir等温模型更适合描述3种生物炭对NOR的吸附，颗粒内扩散方程拟合发现生物炭对NOR的吸附包括快速外扩散与缓慢内扩散；XM300对NOR的吸附容量最大（40.30 mg/g），得益于低热解温度生物炭中存在大量非碳化有机质的分配作用。

关键词: 生物炭, 诺氟沙星, 小麦秸秆, 吸附, 分配作用

CLC Number: 

• X703.1