Ferromanganese ore is an important raw material for the beneficiation and smelting of manganese and iron.The efficient separation of manganese and iron is challenging due to the isomorphism and dispersion of fine particles.The process of hydrogen-based mineral phase transformation and magnetic separation was developed,and the effects of roasting temperature,roasting time,reduction gas concentration,and total gas flow on the separation of ferromanganese and the rate of conversion of divalent manganese were investigated.Iron concentrate with 55.24％iron grade and 91.07％recovery and manganese concentrate with 34.80％manganese grade,77.11％recovery,and 88.79％conversion of Mn2+were obtained under the roasting temperature of 660 ℃,roasting duration of 30 min,volume ratio of carbon monoxide to hydrogen of 1∶3,reduction gas volume fraction of 60％,total gas flow rate of 500 mL·min-1,and magnetic field intensity of 8.51 × 104 A·m-1.Chemical composition analysis,X-ray diffraction(XRD)analysis,and scanning electron microscope-energy dispersion spectra(SEM-EDS)analysis confirmed the effective separation of manganese and iron minerals.The raw ore was mainly composed of limonite,pyrolusite,and quartz.Most weakly magnetic iron ores were transformed into strong magnetic iron minerals after suspension magnetization roasting,whereas pyrolusite was transformed into manganosite after reduction roasting.The primary iron mineral in the iron concentrate was magnetite,containing a small amount of metallic iron.The main manganese mineral in manganese concentrate was manganosite,and the gangue mineral was quartz.Due to the remarkable differences in the magnetic properties of the iron and manganese minerals,efficient separation was achieved through magnetic means.The content of divalent manganese in the manganese concentrate was increased considerably by controlling the process conditions during the hydrogen-based mineral phase transformation,enabling the manganese mineral to be extracted easily by leaching.Thus,the goal of full component utilization of the raw ore and tailless beneficiation was achieved.This novel approach for the clean and efficient utilization of high iron and low manganese ores holds promise for the conversion and synchronous separation of the iron and manganese minerals,achieving the goal of"source reduction,efficient conversion,and precise recovery,"and achieving excellent economic and social benefits.
Elemental sulfur and other sulfur-containing intermediates and derivatives are formed during chalcopyrite bioleaching.The formation of these products can hamper or facilitate the dissolution of chalcopyrite.The study of sulfur speciation transformation during chalcopyrite bioleaching is a useful way to reveal the speciation and formation of the key materials that hamper or enhance the dissolution of chalcopyrite,therefore,to further understand the passivating mechanism of chalcopyrite,and provide theoretical foundation for further understanding of chalcopyrite dissolution mechanism.The progress on research of the characterization of the sulfur species and their transformation in chalcopyrite bioleaching are reviewed.
硫化浮选法是回收铜、铅、锌氧化矿常用的浮选工艺.为获得更高的回收率,研究人员常使用一些阴阳离子对硫化过程进行强化.文章通过对近些年铜、铅、锌氧化矿强化硫化浮选相关研究成果的梳理,阐述了铜、铅、锌氧化矿硫化浮选机制,讨论了铵根离子、铅离子、铜离子、锌离子、氟离子、氯离子、碳酸根离子等阴阳离子的强化机理,综述了其强化硫化基础理论研究的进展,并对未来发展方向进行了展望,以期对铜、铅、锌氧化矿强化硫化浮选的研究提供一定的帮助.
锡是现代工业不可或缺的关键战略金属,我国的锡矿资源十分丰富,但随着优质锡矿的消耗,锡矿资源贫、细、杂的特点越来越突出,微细颗粒、伴生组分复杂也是回收锡矿资源面临的技术难题.浮选作为回收微细粒锡石的主要方法,浮选药剂的选择至关重要.概述了常见的脂肪酸类捕收剂、胂酸类捕收剂、膦酸类捕收剂、烷基磺化琥珀酸捕收剂和羟肟酸类捕收剂的特点及作用机理,重点介绍了新型羟肟酸捕收剂在锡石浮选中的应用成果,以及捕收剂与活化剂、抑制剂在锡石浮选过程的组合使用,为锡石新药剂研发提供参考.
氧化铜矿是我国重要的铜矿资源,近年来易选铜矿资源逐年减少,因而,氧化铜矿的高效选别对铜资源的回收有着重要意义.由于现存氧化铜矿大多嵌布粒度细、含泥量大,难以与脉石矿物分离,使用常规活化剂处理难以达到理想的选矿指标.以 2,5-二硫酚-1,3,4-硫代二唑为基础,通过一锅法合成了新型高效氧化铜矿活化剂DX-2.浮选实验结果表明:针对含铜1.23%、氧化率为 90.24%的难选氧化铜矿,采用DX-2 为活化剂、硫化钠为硫化剂,在pH=8 的条件下,以戊基黄药、烷基羟肟酸钠为捕收剂,松油醇为起泡剂,得到了铜品位为 18.37%、回收率为 82.59%的铜精矿,为难处理氧化铜矿的高效浮选提供了新的技术途径.
