Preparation of a lanthanum-modified flocculant and its removal performance towards phosphorus and fluoride in yellow phosphorus wastewater

Boxuan Li; Shaoxin Wen; Jiacheng Li; Dedong He; Yongming Luo; Xiangqian Zheng; Dingkai Chen

doi:10.1039/d4ra07237e

Preparation of a lanthanum-modified flocculant and its removal performance towards phosphorus and fluoride in yellow phosphorus wastewater

RSC Adv. 2025 Jan 2;15(1):48-57. doi: 10.1039/d4ra07237e.

Authors

Boxuan Li^{1

2

3}, Shaoxin Wen^{1

2

3}, Jiacheng Li^{1

2

3}, Dedong He^{1

2

3}, Yongming Luo^{1

2

3}, Xiangqian Zheng^{1

2

3

4}, Dingkai Chen^{1

2

3}

Affiliations

¹ Faculty of Chemical Engineering, Kunming University of Science and Technology Kunming 650500 P. R. China [email protected] [email protected].
² The Innovation Team for Volatile Organic Compounds Pollutants Control and Resource Utilization of Yunnan Province Kunming 650500 P. R. China.
³ The Higher Educational Key Laboratory for Odorous Volatile Organic Compounds Pollutants Control of Yunnan Province Kunming 650500 P. R. China.
⁴ Institute for Inspection and Certification of Xishuangbanna Dai Autonomous Prefecture Jinghong 666100 P. R. China.

Abstract

Polysilicate-ferric-calcium-lanthanum (PSFCL) was synthesized through a co-polymerization method in order to treat the yellow phosphorus wastewater. Its morphology, composition and functional group were analyzed by X-ray Diffraction (XRD), Fourier Transform-Infrared Spectroscopy (FTIR), Scanning Electron Microscopic (SEM) and X-ray Photoelectron Spectroscopy (XPS), respectively. The optimization of the flocculant was also investigated, including La/Si molar ratio, pH, agitation time, dosage and sedimentation time. Results showed that PSFCL has reached an excellent removal efficiency of 95% and 97% towards phosphorus and fluoride, respectively. It could be inferred that charge neutralization, bridging effect and ligand exchange were the main coagulation mechanisms. As a whole, after the introduction of lanthanum, PSFCL was found to be a promising flocculant in yellow phosphorus wastewater treatment owing to its high removal efficiency and simple synthesis route.