Effect of Pyrolysis Temperature on Adsorption Characteristics of Biochar Derived from Corn Straw

Abstract

With the growth of population and the rapid development of industry, a large amount of wastewater containing heavy metals has been produced. How to treat wastewater containing heavy metals effectively is an important problem. In this study, biochar derived from corn straw is prepared at different carbonization temperatures by oxygen-limited carbonization, and finally, biochar derived from the corn straw at different temperatures is obtained. Then, the adsorption characteristics of ionic heavy metal copper in aqueous solution were studied by biochar prepared at different temperatures. Adsorption kinetics of copper in aqueous solution by biochar from corn straw is discussed in detail. Experimental results show that the adsorption capacity of Cu2+ ions in solution by biochar prepared at different temperatures is significantly different. The prepared biochar derived from corn straw is a fragmentary and porous structure. A lot of functional groups appear on the prepared biochar. The pseudo second order kinetic equation can better describe the entire adsorption of Cu2+ ions in solution by biochar prepared under different temperatures. The adsorption process of Cu2+ ions by biochar is controlled by liquid diffusion and intraparticle diffusion.

Keywords

• adsorption, copper biochar, corn straw, pyrolysis