LI Feng1，FU Dun1,2，CUI Futian1，CUI Xitong1，GUI Herong1
(1.National Engineering Research Center of Coal Mine Water Hazard Controlling，School of Resources and Civil Engineering，Suzhou University，Suzhou 234000，China；
2.School of Earth and Space Sciences，University of Science and Technology of China，Hefei 230026，China)
Abstract: In this study, a novel composite (FeS2/BC) was developed by pyrolysis of solid digestate combined with hydrothermal reaction for As(Ⅲ) removal. The physico-chemical properties of FeS2/BC were analyzed by field emission scanning electron microscope (FESEM), X-ray diffraction techniques (XRD) and specific surface area analyser. The effects of FeS2/BC mass ratio, reaction time, initial concentration of As(Ⅲ) and persulfate (PS) on the adsorption and oxidation removal of As(Ⅲ) were investigated. The results showed that FeS2 was successfully loaded onto BC; under the same As(Ⅲ) adsorption conditions, FeS2/BC(1:1) with a more FeS2 loading amount had the highest As(Ⅲ) adsorption performance (84.5%), and the adsorption process were ascribed to both monolayer and multilayer adsorption. The optimum PS concentration of FeS2/BC(1:1) for As(Ⅲ) removal was 200 μM. In the presence of PS, the kobs of As(Ⅲ) by FeS2/BC(1:1) was 0.0835 min-1, which achieved the cohesion effect of ‘1+1>2’ and shorten the remediation process of As(Ⅲ). Overall, this study suggests that the composite is a promising adsorbent and catalyst for As(Ⅲ) removal from aqueous solutions.
Key word: Biochar-based composite; Arsenic; Adsorption; Oxidative removal; Water treatment
EARTH AND ENVIRONMENT Vol.49, No.5, Tot No.343, 2021, Page 578-585
