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Updated: Jul 18, 2026
08:01
Removal of Arsenic Using a Cationic Polymer Gel Impregnated with Iron Hydroxide
Published on: June 28, 2019
Chromate sorption and reduction kinetics onto an aminated biosorbent
1Department of Environmental Science & Engineering, Tsinghua University, Beijing, China, 100084. dengshubo@tsinghua.edu.cn
Summary
Chemically modified fungal biomass using polyethylenimine (PEI) effectively removes toxic Cr(VI) from water. This novel biosorbent shows a 7.2-fold increase in chromium sorption capacity.
Area of Science:
- Environmental Science
- Materials Science
- Biotechnology
Background:
- Hexavalent chromium (Cr(VI)) is a toxic pollutant in aqueous solutions.
- Fungal biomass offers potential as a low-cost biosorbent for heavy metal removal.
- Surface modification can enhance the efficiency of biosorbents.
Purpose of the Study:
- To develop a novel biosorbent by grafting polyethylenimine (PEI) onto Penicillium chrysogenum fungal biomass.
- To evaluate the Cr(VI) removal efficiency of the modified biosorbent from aqueous solutions.
- To investigate the mechanism of Cr(VI) sorption and reduction.
Main Methods:
- Two-step chemical grafting of PEI onto Penicillium chrysogenum biomass.
- Batch sorption experiments to determine Cr(VI) removal capacity and kinetics.
- X-ray photoelectron spectroscopy (XPS) analysis to characterize chromium species on the biosorbent surface.
Main Results:
- The modified biosorbent exhibited a 7.2-fold increase in Cr(VI) sorption capacity compared to unmodified biomass.
- Sorption kinetics followed a pseudo-second-order model, indicating chemisorption.
- XPS analysis confirmed Cr(VI) reduction to Cr(III) and subsequent chelation with surface amine groups.
Conclusions:
- Surface modification of fungal biomass with PEI is an effective strategy for enhancing Cr(VI) removal.
- The biosorbent facilitates Cr(VI) reduction to Cr(III), improving its sequestration.
- This PEI-grafted fungal biosorbent shows promise for treating Cr(VI)-contaminated wastewater.
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