Work

Zirconium Phosphate Supported on Biochar for Effective Recovery of Rare Earth Elements from Tailwater: A Case Study of La3+

Year: 2026

Type: article

Abstract: The efficient recovery of rare earth elements (REEs) from low-concentration mine tailwater is crucial for resource sustainability. In this study, a novel composite adsorbent, sesame stalk biochar-supported zirconium phosphate (sBC/ZrP), was synthesized for the selective adsorption and recovery of La3+ as a representative REE. The material was characterized using SEM-EDS, BET, XRD, FTIR, and XPS. Batch adsorption experiments were conducted to evaluate the effects of pH, coexisting ions, and the adsorption kinetics and thermodynamics. The results showed that sBC/ZrP exhibited a high adsorption capacity (up to 185.83 mg/g at 35 °C for 4 h) and strong selectivity for La3+, particularly in the presence of common competing cations, although Al3+ demonstrated significant interference. The adsorption process followed pseudo-second-order kinetics and the Langmuir isotherm model, indicating monolayer chemisorption, and was determined to be spontaneous and endothermic. The material maintained over 90% adsorption efficiency after five consecutive adsorption–desorption cycles. The mechanism primarily involved complexation of La3+ with the P-OH and Zr-O groups on the composite. This work demonstrates that sBC/ZrP is a highly efficient, stable, and reusable adsorbent with significant potential for the recovery of REEs from mining tailwater.

Source: Metals

DOI: 10.3390/met16010084

Authors: Ning Zheng, Chenliang Peng, Xia Zhu, Weichang Kong, Yang Yang

Institution: Jiangxi University of Science and Technology

Language: English

Topic: Extraction and Separation Processes

Subfield: Mechanical Engineering

Field: Engineering

Domain: Physical Sciences

SDGs: Clean water and sanitation, Responsible consumption and production

Open Access status: gold

Estimated APC paid: $3,137