Microalgal-biochar immobilized complex: A novel efficient biosorbent for cadmium removal from aqueous solution

Ying Shen; Huan Li; Wenzhe Zhu; Shih-Hsin Ho; Wenqiao Yuan; Jianfeng Chen; Youping Xie

doi:10.1016/j.biortech.2017.08.085

Microalgal-biochar immobilized complex: A novel efficient biosorbent for cadmium removal from aqueous solution

Bioresour Technol. 2017 Nov;244(Pt 1):1031-1038. doi: 10.1016/j.biortech.2017.08.085. Epub 2017 Aug 19.

Authors

Ying Shen¹, Huan Li², Wenzhe Zhu², Shih-Hsin Ho³, Wenqiao Yuan⁴, Jianfeng Chen³, Youping Xie⁵

Affiliations

¹ College of Mechanical Engineering and Automation, Fuzhou University, Fuzhou 350116, China; Collaborative Innovation Center of High-End Equipment Manufacturing in Fujian, Fuzhou 350116, China.
² College of Mechanical Engineering and Automation, Fuzhou University, Fuzhou 350116, China.
³ College of Biological Science and Engineering, Fuzhou University, Fuzhou 350116, China.
⁴ Department of Biological and Agricultural Engineering, North Carolina State University, Raleigh, NC 27695-7625, USA.
⁵ College of Biological Science and Engineering, Fuzhou University, Fuzhou 350116, China. Electronic address: ypxie@fzu.edu.cn.

PMID: 28847109
DOI: 10.1016/j.biortech.2017.08.085

Abstract

The feasibility of the bioremediation of cadmium (Cd) using microalgal-biochar immobilized complex (MBIC) was investigated. Major operating parameters (e.g., pH, biosorbent dosage, initial Cd(II) concentration and microalgal-biochar ratio) were varied to compare the treatability of viable algae (Chlorella sp.), biochar and MBIC. The biosorption isotherms obtained by using algae or biochar were found to have satisfactory Langmuir predictions, while the best fitting adsorption isotherm model for MBIC was the Sips model. The maximum Cd(II) adsorption capacity of MBIC with a Chlorella sp.: biochar ratio of 2:3 (217.41mgg^-1) was higher than that of Chlorella sp. (169.92mgg^-1) or biochar (95.82mgg^-1) alone. The pseudo-second-order model fitted the biosorption process of MBIC well (R²>0.999). Moreover, zeta potential, SEM and FTIR studies revealed that electrostatic attraction, ion exchange and surface complexation were the main mechanisms responsible for Cd removal when using MBIC.

Keywords: Biochar; Biosorption; Cadmium; Chlorella sp.; Immobilized.

MeSH terms

Adsorption
Cadmium*
Charcoal*
Chlorella
Hydrogen-Ion Concentration
Microalgae*
Water Purification*

Substances

biochar
Cadmium
Charcoal