Abstract

• Biochar (BC) derived from peanut hulls is a potential low-cost adsorbent for metal ions and organic pollutants, but its practical application is still limited by the adsorption capacity. In this study, cellulose diacetate (CDA) was prepared from waste cigarette filters by solution casting method. A cellulose diacetate magnetic biochar (CDMBC) and cellulose diacetate biochar (CDBC) were synthesized through chemical co-precipitation, with cellulose diacetate from prepared magnetic biochar (MBC) and biochar (BC). The morphologies, surface chemical structures, and crystallinity of the prepared BC, MBC, CDBC and CDMBC were characterized by SEM, XRD, TG-DTA, and FT IR. The adsorption of Cr(VI) ions by using different biochars as adsorbents was investigated under different adsorption conditions. Batch experiments were conducted to investigate the effect of metal concentrations, adsorbent dosage, time and pH values on the adsorption of Cr(VI). The Freundlich and Langmuir isotherm models were utilized in the analysis of experimental results to determine the optimal fit for the adsorption process of Cr(VI). CDMBC biochar showed the highest removal efficiency of Cr(VI) ions, attributed to enhanced surface area, active sites, and improved magnetic properties. In this research, the cellulose diacetate derived magnetic biochar could be used to remove the Cr(VI) ions in the environmental pollution of Cr(VI) contaminated waste water.