Work

A Novel Effective Arsenic Removal Technique for High-Arsenic Copper Minerals: Two-Stage Filtration Technology Based on Fe-25Al Porous Material

Year: 2025

Type: article

Abstract: Effective arsenic removal is a challenge when smelting high-arsenic copper minerals (HACMs, As > 3.0 wt%). Current arsenic-removal methods for HACM smelting cannot effectively remove arsenic and do not satisfy environmental requirements. This study argues that two-stage filtration based on Fe-25Al porous material and oxygen-controlled roasting is an effective technique for HACM arsenic removal (As = 11.8 wt%). The use of two-stage filtration facilitated double interception: particles larger than 10 μm were mechanically intercepted by the pore channels, and submicron particles (0.1–10 μm) were intercepted by the filter cake. Specifically, in the second stage, the flue gas underwent gradient rapid cooling, and the arsenic in the flue gas rapidly condensed, resulting in efficient arsenic removal. The purity of the condensed product, As2O3, was greater than 99%. Moreover, adding sand to the roasted mineral increased the specific surface area from 0.484 m2/g to 0.590 m2/g, reducing the “bottleneck effect” of pores; the addition of carbon further increased the surface area to 2.457 m2/g, inhibiting the formation of arsenate. When the mineral feed rate increased from 50 kg/h to 80 kg/h, the oxygen partial pressure decreased; this effectively inhibited the formation of iron arsenate, and the arsenic removal efficiency increased from 70.20% to 95.61%. The optimized process achieved ≥94% arsenic removal efficiency and ≥76% sulfur-fixation efficiency, with low energy cost. Material balance analysis showed that after arsenic removal, the Cu/Si to Fe/Si ratio of the copper mineral reached 1.5, which is appropriate for immediate subsequent smelting. This study provides a new technological strategy for HACM arsenic removal.

Source: Applied Sciences

DOI: 10.3390/app15168899

Authors: Xiaowei Tang, Yuehui He

Institutions: Central South University, State Key Laboratory of Powder Metallurgy, Changsha University of Science and Technology

Language: English

Topic: Metallurgical Processes and Thermodynamics

Subfield: Mechanical Engineering

Field: Engineering

Domain: Physical Sciences

SDGs: Responsible consumption and production, Clean water and sanitation

Open Access status: gold

Estimated APC paid: $2,896