Removal of chromium(VI) and orange II from aqueous solution using magnetic polyetherimide/sugarcane bagasse

A novel biological magnetic adsorbent was successfully constituted with sugarcane bagasse (SCB), polyetherimide (PEI) and Fe3O4. The physicochemical properties of the adsorbent (Fe3O4@PEI/SCB) were investigated by SEM, BET, VSM, XRD, TGA, FT-IR, XPS, TEM and UV–Vis. The adsorption capacity was measured using Cr(VI) and orange II as adsorbates. The effects of initial pH, dosage, contact time, and ionic strength on the adsorption capacity were investigated in detail. Fe3O4@PEI/SCB is a mesoporous material and the mass ratio of Fe3O4:PEI:SCB is about 5:2:15. Adsorption capacity could reach 182.28 mg/g and 1893.57 mg/g for Cr(VI) and orange II at room temperature, respectively. Fe3O4@PEI/SCB is a green and economical material, which is very easily regenerated, reused, and separated in the adsorption. The most important factor is the ionic strength and major adsorption interaction was electrostatic in this work.