Preparation and Characterization of an Invasive Plant-Derived Biochar-Supported Nano-Sized Lanthanum Composite and Its Application in Phosphate Capture from Aqueous Media

Enmin Zong; Yuanyuan Shen; Jiayao Yang; Xiaohuan Liu; Pingan Song

doi:10.1021/acsomega.3c00992

Preparation and Characterization of an Invasive Plant-Derived Biochar-Supported Nano-Sized Lanthanum Composite and Its Application in Phosphate Capture from Aqueous Media

ACS Omega. 2023 Apr 5;8(15):14177-14189. doi: 10.1021/acsomega.3c00992. eCollection 2023 Apr 18.

Authors

Enmin Zong^{1

2}, Yuanyuan Shen¹, Jiayao Yang³, Xiaohuan Liu^{1

3}, Pingan Song⁴

Affiliations

¹ College of Life Science, Zhejiang Provincial Key Laboratory of Plant Evolutionary Ecology and Conservation, Taizhou University, Taizhou 318000, P. R. China.
² School of Earth Sciences and Engineering, Nanjing University, Nanjing 210093, P. R. China.
³ School of Engineering, Zhejiang A&F University, Hangzhou 311300, P. R. China.
⁴ Centre for Future Materials, University of Southern Queensland, Springfield 4350, Australia.

Abstract

Invasive plants pose a great threat to natural ecosystems owing to their rapid propagation and spreading ability in nature. Herein, a typical invasive plant, Solidago canadensis, was chosen as a novel feedstock for the preparation of nano-sized lanthanum-loaded S. canadensis-derived biochar (SCBC-La), and its adsorption performance for phosphate removal was evaluated by batch adsorption experiment. The composite was characterized by multiple techniques. Effects of parameters, such as the initial concentration of phosphate, time, pH, coexisting ions, and ionic strength, were studied on the phosphate removal. Adsorption kinetics and isotherms showed that SCBC-La shows a faster adsorption rate at a low concentration and SCBC-La exhibits good La utilization efficiency than some of the reported La-modified adsorbents. Phosphate can be effectively removed over a relatively wide pH of 3-9 because of the high pH _pzc of SCBC-La. Furthermore, the SCBC-La shows a strong anti-interference capability in terms of pH value, coexisting ions, and ionic strength, exhibiting a highly selective capacity for phosphate removal. Additionally, Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) measurements reveal that hydroxyl groups on the surface of SCBC-La were replaced by phosphate and manifest the reversible transformation between La(OH)₃ and LaPO₄. Considering its high adsorption capacity and excellent selectivity, SCBC-La is a promising material for preventing eutrophication. This work gives a new method of pollution control with waste treatment since the invasive plant (S. canadensis) is converted into biochar-based nanocomposite for effective removal of phosphate to mitigate eutrophication.