NanoDay 2021 – Poster 02 – Yicheng Yang

 

Ball Milling Biochar Iron Oxide Composites for the Removal of Chromium (Cr(VI)) from Water: Performance and Mechanisms

Yicheng Yang

Authors: Yicheng Yang, Haowen Zou, Yulin Zheng, Jinsheng Huang, Yue Zhang, Bin Gao

Faculty Mentor: Bin Gao, PhD

College: College of Engineering

Department: Agricultural and Biological Engineering

Abstract

A novel biochar/iron oxide composite (BM-Fe-HC) was successfully prepared by simply ball milling iron-laden biochar (Fe-HC). The performance and mechanisms of Cr(VI) removal by BM-Fe-HC were investigated. Ball milling effectively reduced particle size, increased specific surface area, more importantly, enhanced the distribution and increased the exposure of iron oxides on biochar surface. As a result, Cr(VI) removal by BM-Fe-HC showed fast kinetics and large adsorption capacity with a maximum capacity of 48.1 mg/g, higher than that of other biochar/iron composites reported in the literature. Acidic pH promoted Cr(VI) removal while competition ions (Cl-, SO42- and PO43-) inhibited Cr(VI) removal by BM-Fe-HC. Comparison of pre- and post-adsorption samples revealed that iron oxides of the BM-Fe-HC played the dominant role in the adsorption and reduction of Cr(VI) during the removal. After adsorption, part of adsorbed Cr(VI) was reduced by Fe(II) and then stabilized by Fe(III) on the composite surface. All the results demonstrate that novel ball-milled biochar/iron oxide composites can be used as an effective adsorbent to remove Cr(VI) from water.

Poster