Resource utilization of a typical vegetable waste as biochars in removing phthalate acid esters from water: A sorption case study.

It is very important to utilize associated vegetable products as resources, especially in large-scale vegetable cultivation areas. In this study, pepper straw, a vegetable waste, was pyrolyzed into pepper straw biochars (PBs) to investigate their sorption potential for phthalate acid esters (PAEs). The results showed that PBs have porous structures and abundant surface functional groups. Dibutyl phthalate (DBP) and dimethyl phthalate (DMP) removal by PBs was divided into two stages, fast and slow sorption. The PBs pyrolyzed at 500 °C showed greater DBP and DMP sorption capacity than those pyrolyzed at 400 and 600 °C. Both chemical and physical sorption occurred in the whole sorption process of PAEs to PBs. It is proposed that converting pepper straw into biochars to use as sorbents could be an environmentally friendly way of vegetable waste resource utilization.