Title: Literature Review: Iron Extraction From Copper Smelting Slag And Direct Reduced Iron (Dri/Hbi) Production
Authors: Kholikulov D.B., Mutalibkhonov S.S., Khudoymuratov Sh.J.
Volume: 9
Issue: 11
Pages: 53-59
Publication Date: 2025/11/28
Abstract:
Studies on anode slime processing further highlight the potential of pressure leaching for near-complete nickel extraction under optimized acidic and oxidizing conditions. Overall, the literature indicates that well-designed hybrid systems offer the most effective balance of selectivity, energy efficiency, and environmental sustainability for nickel recovery. Copper smelting slag represents a significant environmental challenge, with accumulated quantities exceeding 1.8 billion tonnes globally. This slag contains 35-45 wt% iron primarily in the form of fayalite (Fe?SiO?) and magnetite (Fe?O?), making it an attractive secondary source for iron recovery. The present literature review synthesizes recent research (2013-2025) from Scopus and Web of Science indexed journals on iron extraction from copper smelting slag and its subsequent conversion to direct reduced iron (DRI) and hot briquetted iron (HBI) for steelmaking applications. Major iron recovery methods include coal-based direct reduction combined with magnetic separation (achieving 91-98% iron recovery), hydrogen-based reduction, oxidation-roasting magnetic separation, carbothermal reduction, and hydrometallurgical processing. Current findings demonstrate that reduction temperature (1200-1300°C), reductant type, slag basicity adjustment, and additive incorporation critically influence recovery efficiency. Hydrogen-based direct reduction emerges as the most promising technology for sustainable iron recovery, achieving superior metallization degrees (94-95%) while enabling near-zero CO? emissions when coupled with renewable electricity. Global DRI/HBI production is projected to increase from 115 Mt/year (2019) to 212.6 Mt/year (2050), with hydrogen-based production dominating future production. This review synthesizes optimal process parameters, kinetic mechanisms, thermodynamic principles, and technological innovations essential for advancing sustainable iron recovery and low-carbon steelmaking.