Resource utilization of rice husk biomass: Preparation of MgO flake-modified biochar for simultaneous removal of heavy metals from aqueous solution and polluted soil

Anyu Li; Hanquan Xie; Ying Qiu; Lihu Liu; Tao Lu; Weihua Wang; Guohong Qiu

doi:10.1016/j.envpol.2022.119869

Resource utilization of rice husk biomass: Preparation of MgO flake-modified biochar for simultaneous removal of heavy metals from aqueous solution and polluted soil

Environ Pollut. 2022 Oct 1:310:119869. doi: 10.1016/j.envpol.2022.119869. Epub 2022 Aug 1.

Authors

Anyu Li¹, Hanquan Xie¹, Ying Qiu¹, Lihu Liu¹, Tao Lu¹, Weihua Wang¹, Guohong Qiu²

Affiliations

¹ Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture and Rural Affairs, Hubei Key Laboratory of Soil Environment and Pollution Remediation, State Environmental Protection Key Laboratory of Soil Health and Green Remediation, College of Resources and Environment, Shenzhen Institute of Nutrition and Health, Interdisciplinary Sciences Institute, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China; Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China.
² Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture and Rural Affairs, Hubei Key Laboratory of Soil Environment and Pollution Remediation, State Environmental Protection Key Laboratory of Soil Health and Green Remediation, College of Resources and Environment, Shenzhen Institute of Nutrition and Health, Interdisciplinary Sciences Institute, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China; Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China. Electronic address: qiugh@mail.hzau.edu.cn.

PMID: 35926734
DOI: 10.1016/j.envpol.2022.119869

Abstract

In general, the remediation performance of heavy metals can be further improved by metal-oxide modified biochar. This work used MgO-modified rice husk biochar (MgO-5%@RHB-450 and MgO-5%@RHB-600) with high surface activity for simultaneous remediation and removal of heavy metals in soil and wastewater. The adsorption of MgO-5%@RHB-450/MgO-5%@RHB-600 for Cd(II), Cu(II), Zn(II) and Cr(VI) followed the pseudo-second order, with the adsorption capacities reaching 91.13/104.68, 166.68/173.22, 80.12/104.38 and 38.88/47.02 mg g^-1, respectively. The addition of 1.0% MgO-5%@RHB-450 and MgO-5%@RHB-600 could effectively decrease the CaCl₂-extractable Cd concentration (CaCl₂-Cd) by 66.2% and 70.0%, respectively. Moreover, MgO-5%@RHB-450 and MgO-5%@RHB-600 facilitated the transformation of exchangeable fractions to carbonate-bound and residual fractions, and reduced the exchangeable fractions by 8.1% and 9.6%, respectively. The mechanisms for the removal of heavy metals from wastewater by MgO-5%@RHB-450 and MgO-5%@RHB-600 mainly included complexation, ion exchange and precipitation, and the immobilization mechanisms in soil may be precipitation, complexation and pore filling. In general, this study provides high-efficiency functional materials for the remediation of heavy metal pollution.

Keywords: Adsorption; Heavy metal; MgO-Loaded biochar; Soil remediation.

MeSH terms

Adsorption
Biomass
Cadmium
Calcium Chloride
Charcoal
Magnesium Oxide
Metals, Heavy*
Oryza*
Soil
Soil Pollutants*
Wastewater

Substances

Metals, Heavy
Soil
Soil Pollutants
Waste Water
biochar
Cadmium
Charcoal
Magnesium Oxide
Calcium Chloride