Adsorption of arsenic (III) from aqueous solution by a novel phosphorus-modified biochar obtained from Taraxacum mongolicum Hand-Mazz: Adsorption behavior and mechanistic analysis

Waqas Ahmed; Sajid Mehmood; Avelino Núñez-Delgado; Sehrish Ali; Muhammad Qaswar; Awais Shakoor; Ali Akbar Maitlo; Di-Yun Chen

doi:10.1016/j.jenvman.2021.112764

Adsorption of arsenic (III) from aqueous solution by a novel phosphorus-modified biochar obtained from Taraxacum mongolicum Hand-Mazz: Adsorption behavior and mechanistic analysis

J Environ Manage. 2021 Aug 15:292:112764. doi: 10.1016/j.jenvman.2021.112764. Epub 2021 May 10.

Authors

Waqas Ahmed¹, Sajid Mehmood¹, Avelino Núñez-Delgado², Sehrish Ali³, Muhammad Qaswar⁴, Awais Shakoor⁵, Ali Akbar Maitlo⁶, Di-Yun Chen⁷

Affiliations

¹ Guangdong Provincial Key Laboratory for Radionuclides Pollution Control and Resources, School of Environmental Science and Engineering, Guangzhou University, Guangzhou, 510006, China; School of Civil Engineering, Guangzhou University, Guangzhou, 510006, PR China.
² Department of Soil Science and Agricultural Chemistry, Engineering Polytechnic School, Universidade de Santiago de Compostela, 27002, Lugo, Spain.
³ National Engineering Laboratory for Improving Quality of Arable Land, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
⁴ Key Laboratory of Industrial Ecology and Environmental Engineering, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China.
⁵ Department of Environment and Soil Sciences, University of Lleida, 25198, Lleida, Spain.
⁶ National Engineering Laboratory for Improving Quality of Arable Land, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China; Soil Fertility Research Institute, Agriculture Research Center, Tandojam, 70060, Department of Agriculture, Government of Sindh, Pakistan.
⁷ Guangdong Provincial Key Laboratory for Radionuclides Pollution Control and Resources, School of Environmental Science and Engineering, Guangzhou University, Guangzhou, 510006, China; School of Civil Engineering, Guangzhou University, Guangzhou, 510006, PR China. Electronic address: cdy@gzhu.edu.cn.

PMID: 33984639
DOI: 10.1016/j.jenvman.2021.112764

Abstract

A novel phosphorus (P) modified biochar (PLBC) was produced by pyrolyzing biomass of the dietic herb Taraxacum mongolicum Hand-Mazz (TMHM) and treating it with monopotassium phosphate (KH₂PO₄). This phosphorous loaded biochar was then assessed as adsorbent for As(III) removal from contaminated water. In the current research, the adsorbent was characterized before and after P loading by means of SEM-EDX, TEM, FTIR and XRD techniques. It was evidenced that the presence of P on the surface of the biochar (BC) could improve its efficiency to remove As(III) from contaminated environments. Adsorption kinetics were evaluated by performing batch-type experiments at varied times and pH values (5, 7 and 9). The kinetic study revealed that a contact time of 24 h was required to attain equilibrium and the experimental data were best fitted to the pseudo-second-order kinetic model (q_e = 17.1 mg g^-1). In addition, several batch experiments were conducted with varied arsenic concentrations. During the adsorption tests, the maximum adsorption of As(III) was found at pH 5. The adsorption study further showed that compared to BC, PLBC depicted increased removal of As(III) from contaminated solutions. The adsorption experimental data showed the best fit to the Langmuir isotherm model (with R² = 0.84), with maximum As(III) adsorption capacity reaching 30.76 mg g^-1 for PLBC.

Keywords: Adsorption; Arsenic (III); Biochar; Heavy metal; Modification; Phosphorous.

MeSH terms

Adsorption
Arsenic* / analysis
Charcoal
Hydrogen-Ion Concentration
Kinetics
Phosphorus
Taraxacum*
Water
Water Pollutants, Chemical*

Substances

Water Pollutants, Chemical
biochar
Water
Charcoal
Phosphorus
Arsenic