Efficient removal of Pb(II) through recycled biochar-mineral composite from the coagulation sludge of swine wastewater

Xuewen Luo; Minxian Shen; Zhujian Huang; Zihao Chen; Ziying Chen; Bingjia Lin; Lihua Cui

doi:10.1016/j.envres.2020.110014

Efficient removal of Pb(II) through recycled biochar-mineral composite from the coagulation sludge of swine wastewater

Environ Res. 2020 Nov:190:110014. doi: 10.1016/j.envres.2020.110014. Epub 2020 Aug 5.

Authors

Xuewen Luo¹, Minxian Shen¹, Zhujian Huang², Zihao Chen¹, Ziying Chen³, Bingjia Lin¹, Lihua Cui⁴

Affiliations

¹ College of Natural Resources and Environment, South China Agricultural University, Guangzhou, 510642, China.
² College of Natural Resources and Environment, South China Agricultural University, Guangzhou, 510642, China; Guangdong Laboratory of Lingnan Modern Agriculture, Guangzhou, 510642, China; National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Changsha, Hunan, 410125, China. Electronic address: zjhuang@scau.edu.cn.
³ College of Natural Resources and Environment, South China Agricultural University, Guangzhou, 510642, China; Guangdong Laboratory of Lingnan Modern Agriculture, Guangzhou, 510642, China.
⁴ College of Natural Resources and Environment, South China Agricultural University, Guangzhou, 510642, China; Guangdong Laboratory of Lingnan Modern Agriculture, Guangzhou, 510642, China; National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Changsha, Hunan, 410125, China.

PMID: 32768476
DOI: 10.1016/j.envres.2020.110014

Abstract

Zeolite-Mg/Fe chloride dual enhanced coagulation is a cost-effective method for advanced treatment of swine wastewater, but the sludge generated after the enhanced coagulation remains to be a problem. In this study, the precipitate from a swine wastewater coagulation unit was regenerated by pyrolysis treatment in an O₂-limited environment to develop a high efficient adsorbent (biochar-mineral composite, BMC) for the removal of Pb(II) from wastewater. SEM images indicate that complex Mg/Fe oxides and sludge biochar gathered around zeolite particles. Effects of different influencing factors such as Pb(II) initial concentration, pH, adsorption time and ion concentration on the adsorption performance were investigated. The results show that the Langmuir isotherm model can better express the adsorption of Pb(II) on BMC than Freundlich model and Temkin model. BMC pyrolyzed at 500 °C showed the maximum adsorption capacity of 450.58 mg/g under experimental condition of 25 °C, 100 mg/L Pb(II) initial concentration and the initial pH of 5.6. The adsorption mechanisms on BMC mainly include ion exchange, electrostatic interaction. Therefore, it is a cost-effective and environmental-friendly strategy to obtain biochar-mineral composite from recycled sludge, which can efficiently remove Pb(II) from wastewater.

Keywords: Enhanced coagulation; Pb(II) removal; Recycling; Sludge.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adsorption
Animals
Charcoal
Hydrogen-Ion Concentration
Kinetics
Lead
Minerals
Sewage
Swine
Wastewater*
Water Pollutants, Chemical* / analysis

Substances

Minerals
Sewage
Waste Water
Water Pollutants, Chemical
biochar
Charcoal
Lead