不同制备条件对生物焦汞吸附特性及吸附动力学的影响

为获得生物焦对汞的吸附特性,对不同制备条件下的生物焦进行研究。通过分析生物质种类、制备粒径、制备温度以及制备氧浓度对生物焦吸附汞的影响,并结合其吸附动力学过程,进一步探究吸附机理。结果表明:不同制备条件下生物焦汞吸附特性存在差异；生物焦对汞的物理吸附中,孔隙结构对其具有影响,累积孔体积越大,单位汞吸附量越高,利于生物焦对汞的吸附；与比表面积相比,比孔容积在汞吸附过程中发挥更为重要的作用；化学吸附与物理吸附均在生物焦汞吸附过程中起到重要影响,且化学吸附是其主要的控速步骤。

Effects of different preparation conditions on kinetics and adsorption of mercury by biomass char

In order to obtain the characteristic of biomass char on mercury adsorption, the biomass char prepared with various conditions was studied. The influence of preparation condition of biomass char on mercury adsorption was obtained. These preparation parameters include biomass species, particle size, temperature and oxygen concentration. The adsorption kinetic characteristics of biomass char was investigated, which can provide theoretical foundation for further research on the mechanism of biomass char on mercury adsorption. The results show that there are differences in mercury adsorption by biomass char with various preparation conditions. The pore structure influenced greatly in physical adsorption. The more cumulative pore volume of biomass char and thus the more mercury adsorbed. The specific pore volume plays a more significant role than specific surface area in the mercury adsorption process. The adsorption process was effected by both chemical adsorption and physical absorption, and the former is an important rate-limiting process.