One-step solvothermal construction of coral reef-like FeS2/biochar to activate peroxymonosulfate for efficient organic pollutant removal

Over the past few decades, organic pollution such as tetracyclines and dyes has caused harm to the environment, biology, and human health. Therefore, developing a green and efficient method for organic pollutant removal is urgent. Herein, a coral reef-like FeS2/C-cs was successfully constructed by one-step solvothermal growth of FeS2 on waste corn stalks-derived carbon. The as-prepared FeS2/C-cs catalyst exhibited much better performance in activating peroxymonosulfate (PMS) for removing organic pollutants than the other candidates previously reported. Almost 100 % of oxytetracycline (OTC) could be degraded within 20 min. Various factors like PMS concentration, catalyst dosage, initial pH values, and temperature that influenced the degradation process were then investigated. Through quenching experiments and electron paramagnetic resonance (EPR), O-center dot(2)-, O-1(2), SO4 center dot- and (OH)-O-center dot were determined to be involved in attacking OTC, in which SO4 center dot- play a major role and (OH)-O-center dot acted as the secondary role. Subsequently, degradation pathways of OTC were rationally proposed. Toxicity simulations demonstrated that the toxicity of OTC could be effectively reduced after degradation. Universal experiments showed that FeS2/C-cs + PMS system could also effectively degrade other typical tetracyclines and dyes, such as tetracycline (TC, similar to 100 %), chlortetracycline hydrochloride (CTC, similar to 100 %), methylene blue (MB, similar to 83 %) and rhodamine B (RhB, similar to 95 %). Moreover, the FeS2/C-cs could remain high catalytic activity in five cycles test. This study provides a green and efficient method for organic pollution removal and technical guidance for analyzing its environmental toxicology.

Automated summary

Over the past few decades, organic pollution such as tetracyclines and dyes has caused harm to the environment, biology, and human health. Therefore, developing a green and efficient method for organic pollutant removal is urgent. The study successfully constructed a coral reef-like FeS2/C-cs catalyst, which exhibited superior performance in removing organic pollutants compared to previous candidates. Rating: 9 out of 10.