The removal of copper–cyanide complexes from cyanide gold leaching tail water poses a significant challenge, as they are difficult to eliminate and risk causing secondary pollution. This study developed a synergistic flocculation–flotation process using the bio-collector sodium cocoyl glycinate (SCG) and the coagulant polyferric sulfate (PFS) for purification. Simulated wastewater, prepared based on actual gold mine effluent, was treated under optimized conditions of reagent dosage, a solution pH of 6–10, and a flotation time of 1–5 min, achieving high removal efficiencies of 96.48% for copper and 94.68% for total cyanide. Mechanistic studies via FT-IR, Zeta potential, and XPS revealed that Fe3+ from PFS formed Fe-CN complexes with both free and copper-complexed cyanide. Simultaneously, copper ions coordinated with SCG to generate a hydrophobic Fe-CN-Cu-SCG ternary complex, which was subsequently removed by adsorption onto air bubbles via the hydrophobic chains of SCG. This work provides a novel, efficient, and mechanistically clear strategy for the advanced treatment of cyanide-containing tailing water with a gold content of 0.021 mg/L.

Flotation separation of sphalerite (ZnS) from pyrite (FeS₂) is of critical industrial importance but remains technically challenging due to the convergence of their floatability. This challenge is exacerbated by the effects of dissolved metal ions, complex electrochemical interactions, and surface transformation processes. Conventional high-alkalinity flotation routes, while effective to some extent, suffer from excessive reagent consumption, equipment scaling, and adverse environmental impacts. This review systematically summarizes recent fundamental and technological advances in sphalerite-pyrite flotation separation, intending to identify viable pathways toward more efficient and sustainable processes. The mechanisms governing mineral floatability are critically examined from the perspectives of crystal structure and surface chemistry, with particular emphasis on lattice defects, surface oxidation behavior, and the chemical states of iron sites. Building on this foundation, the evolution of separation strategies - from traditional high-alkali regulation to low-alkali or alkali-free flotation, electrochemical potential control, and bio-flotation - is comprehensively reviewed. Special attention is devoted to the molecular design and interfacial interaction mechanisms of flotation reagents. The adsorption configurations, activation pathways, and competitive behavior of Cu2+ ions on sphalerite and pyrite surfaces are elucidated. Comparative analyses of structure-activity relationships between conventional xanthate collectors and emerging heterocyclic nitrogen-sulfur or thiol-based collectors are presented. In addition, the depression mechanisms of inorganic, organic, and combined depressants acting on pyrite are systematically summarized. The review concludes that future breakthroughs in sphalerite-pyrite separation are likely to rely on the practical implementation of low-alkalinity flotation strategies, such as potential-controlled flotation, coupled with the rational molecular design of environmentally benign reagents. The synergistic integration of these approaches offers a promising route toward the sustainable and efficient processing of complex sulfide resources.

The reuse of mineral processing wastewater remains a challenge in certain scenarios, as residual reagents could substantially impair separation efficiency. In this fundamental research, magnetic flocculation separation technology was applied to remove residual surfactants from synthesized mineral processing wastewater. Micron-sized iron powder and polyaluminum chloride (PAC) are adopted as magnetic medium and flocculants. A total organic carbon (TOC) removal efficiency of 94.31

Heterocoagulation between fine particles can interfere with the flotation separation of different minerals. Therefore, the study of particle heterocoagulation is significant. This study found that fine calcite affected galena flotation and examined the interactions between galena and fine calcite particles in suspension pulp. The best flotation behaviour was observed for pure galena minerals at pH 9; however, the flotation separation of galena and fine calcite yielded unsatisfactory results under these conditions. The results of zeta potential measurement, scanning electron microscopy, and X-ray photoelectron spectroscopy indicate that heterocoagulation occurred between the calcite and galena particles at pH 9. The interaction mechanism shows that dissolved hydroxy calcium could be absorbed on the surface of galena and render a positive charge, causing coagulation between the calcite and galena particles due to electrostatic attraction. This new discovery provides a reference for the pre-inhibition of gangue minerals and adjustment of the chemical ratio during the flotation process.

Owing to the toxicity and widespread use of copper, the pollution caused by copper ions has become a long-standing environmental and industrial challenge. In this study, a new adsorbent was developed to dispose of and remove copper ions from water. The modified chitosan–carboxymethyl starch (MCTS-CMS) polymer was characterised, and FTIR and SEM-EDS confirmed the successful graft modification of the receptor. The adsorption behaviour was investigated through various parameters, and the results showed that the optimal parameters were pH > 4.0, an adsorption time of 30 min, a reaction temperature of 293 K, and an initial concentration of 100–120 mg/L. The experimental data exhibited a good fit with pseudo-second-order models, and the Langmuir isotherm revealed that the polymer was found to be highly suitable for adsorption, with a maximum adsorption capacity of 321.16 mg/g. Thermodynamic analysis revealed that the adsorption process was exothermic and spontaneous. XRD and XPS confirmed the generation of posnjakite after the adsorption and the predominant roles of nitrogen- and sulphur-containing groups in the adsorption. Further analysis confirmed the existence of chemisorption and physical adsorption, with chemisorption mainly facilitating the Cu(II) absorption of the polymer. MCTS-CMS showed an excellent removal efficiency of 98% in acidic solutions. On the basis of these findings, the MCTS-CMS polymer demonstrates excellent performance and high selectivity in the removal of copper ions from industrial wastewater or polluted water bodies. This work recommends expanding the polymer’s practical applications to contribute to water purification efforts.

天青石可用于制备碳酸锶,碳酸锶被广泛用于制造阴极射线管、电磁铁及各种锶盐,是一种十分重要的化工原料.重庆大足天青石矿嵌布粒度细,方解石含量高,为有效分离细粒天青石与方解石,采用悬振锥面选矿机对其进行重选分离,结果表明,在磨矿 3.0 min、转动频率 20 Hz、振动频率 14 Hz 的条件下,经悬振锥面选矿机分选,可将原矿品位为 58.43%的天青石富集得到综合品位为 79.39%、综合回收率为 72.16%的天青石精矿.

河南某钼矿尾矿中钼主要以辉钼矿形式赋存,辉钼矿分布在(-530+125)μm和-38 μm的粒级中,脉石矿物主要为钙铁石榴石及石英,该试验采用 HydroFloat水力浮选机对粗颗粒钼尾矿进行分选,达到抛尾的目的.HydroFloat水力浮选机采用流化床技术对矿物进行浮选,同时在选别过程中引入上升水流,使粗颗粒能够克服重力随气泡上升从而达到富集的目的.经水力浮选抛尾后,可将原矿中品位为 0.033%的钼富集得到品位为 0.081%、回收率为 92.18%钼粗精矿,抛尾率为 66.91%.

方铅矿的高效选择性抑制是铅多金属硫化矿浮选领域亟待解决的问题之一.采用硫酸对方铅矿进行表面改性使其可浮性降低从而实现选择性抑制.针对方铅矿纯矿物,采用表面改性试验结合浮选试验,研究并确定了表面改性的主要影响因素和最佳条件.在试验研究基础上,采用响应曲面法对方铅矿表面改性的参数条件进行了优化,建立了主要参数,如硫酸浓度、改性温度、改性时间以及三因素之间的交互作用对方铅矿可浮性影响的多元回归方程,预测数据分析结果表明,优化后的表面最佳改性条件为硫酸浓度2.1 mol/L、改性温度91.08℃、改性时间24.75 min,此时方铅矿的回收率仅为3.52％,实现了方铅矿的高效抑制.预测结果与验证试验结果一致,表明所选模型具有良好的预测性能.

随着科学技术不断进步,在工业应用中对单一稀土纯度的要求越来越高,高效分离纯化稀土元素是充分利用稀土资源的保障.由于绿色环保意识和要求的增强,对稀土分离纯化工艺技术提出了新的挑战.在几十年生产应用中,分离纯化稀土元素的技术方法不断完善改进,文章综述了分级结晶和沉淀法、化学气相传输法、离子交换法、萃取树脂色层法、溶剂萃取法、液膜法和氧化还原法在稀土分离纯化中的应用现状,并对比分析了不同方法存在的优势和弊端.在此基础上,阐述了溶剂萃取法中中性萃取剂、酸性萃取剂、胺类萃取剂和离子液体萃取剂的发展应用现状,同时探讨了络合剂和协同体系对分离稀土性能的影响.并展望了未来稀土分离纯化技术研究的发展方向,为更加绿化高效开发利用稀土资源提供借鉴.

As an important strategic resource,rare earth was widely used in the fields of national defense,aerospace,permanent magnet materials,new energy vehicles,luminescent materials,etc.,and the requirements for the purity of a single rare earth in various fields were getting higher and higher. Therefore,efficient separation technology became the key to rare earth applications. Solvent method,as the most important method for separating rare earths,had been widely studied in practical production applications. At present,organic extractants could be divided into neutral extractants,acidic extractants,alkaline extractants and ionic liquid extractants according to the difference in their properties. Among them,neutral extractants generally included oxygen-containing extractants（lipids,ketones,etc.）,phosphine-containing extractants（phosphonates,phosphine oxides,etc.）,nitrogen-containing extractants（substituted amides）and sulfur-containing extractants（sulfoxides,sulfides）. This type of extractant was used in industrial rare earth extraction due to its advantages of easy stripping and stable extraction,but there were also problems such as easy emulsification and degradation,and the extraction mechanism of rare earth was more complicated. In addition to the neutral coordination mechanism,the agent also had a hydrated cation coordination mechanism,which increased the difficulty of controlling the extraction conditions. Acidic extractants generally included phosphonic acids,carboxylic acids,chelates,etc. This type of extractant had the advantages of good separation effect on rare earth elements,large saturation capacity and strong pertinence,but there were also problems such as difficulty in stripping,easy emulsification,and production of ammonia nitrogen wastewater and damage to the environment,which restricted the development and application of phosphonic acid extractants. Amines compared with acidic extractants,although they had the advantages of large extraction capacity,strong selectivity and good stability,the overall separation effect was lower than that of acidic extractants. More stages were required to achieve rare earth separation,which reduced production efficiency;compared with other traditional extractants,ionic liquid extractants had the advantages of low volatility and stability,strong stability,low toxicity,large adsorption capacity,high designability,and easy circulation. Taking advantage of such advantages,it had good application potential in the field of rare earth extraction and separation. However,during the extraction process,the ionic liquid would enter the solution in the form of ions,causing the loss of the ionic liquid and increasing the production cost. At present,it was still only in the laboratory research stage. With the increasing awareness of green environmental protection,the disadvantages of the original single extraction system for separating rare earths became more and more obvious,and it was very important to develop a green and efficient extraction system and process. The research and application of synergistic extraction system and complex extraction system were expounded. Among them,two or more extraction agents were combined to form a multi-element extraction system,and combined with the advantages of each extraction agent,it could often show higher extraction rate and selectivity,increase the stability of the extract,and improve the organic extraction agent. However,there were still unsolved problems in the synergistic extraction extractant system. For example,when the extractant was recovered during the synergistic extraction process,the molar ratio of the extractant changed due to the difference in solubility and recovery effect. Direct circulation was not conducive to medium and long-term stable operation of the industry. At the same time,the root cause of the synergistic effect had not been discovered,and theoretical research needed to be further developed. The complexation extraction system was mainly to add a certain complexing agent to the extraction system to inhibit or promote the extraction complexation to achieve the purpose of improving the separation effect. Generally,the addition of complexing agents could better promote the extraction and separation of rare earths. In addition,it was basically non-toxic,environmentally friendly,and had the advantages of high reaction efficiency and good selectivity,which made the screening and application of complexing agents very meaningful. However,after the complexing agent was added into the extraction system,it was difficult to be effectively recycled,which was also the main reason for restricting the application of complexing agent in industry. The development of science and technology had higher and higher requirements for the purity of rare earths,and the research on the extraction and separation of rare earths had been widely carried out at home and abroad. In the process of continuous development in recent decades,the solvent method had been continuously improved and innovated as the most important method of current industrial production,and the limitations of other types of extraction methods had also been continuously overcome,jointly promoting the development of green technology for rare earth extraction and separation. Although many studies were still in the stage of laboratory research and application,this also laid a theoretical foundation for industrial production and application,and contributed to the better utilization of rare earth resources.

铜铅硫化矿的高效浮选分离一直是选矿领域的重点和难点.针对铜铅硫化混合精矿,提出采用硫酸预处理—浮选分离新工艺,通过对黄铜矿和方铅矿单矿物硫酸处理前后的接触角测定、人工混合矿和实际铜铅混合精矿预处理—浮选分离试验研究,分析了硫酸对方铅矿和黄铜矿的作用机理,确定了最佳预处理条件.研究结果表明,硫酸预处理后方铅矿的表面接触角大幅降低并受到选择性抑制,而黄铜矿的可浮性不受影响;人工混合矿的最佳预处理条件为硫酸浓度2.0 mol/L,温度100℃,处理时间25 min;针对含Pb 15.74％、Cu 11.58％ 的实际铜铅混合硫化精矿,采用"预处理-铜铅浮选分离"新工艺,获得铜精矿Cu品位18.12％,含Pb 2.87％,Cu回收率94.80％;铅精矿Pb品位36.15％,含Cu 1.54％,Pb回收率89.92％ 的良好指标,对铜铅硫化混合精矿的高效分离提供了新思路.

粗颗粒浮选技术提高了矿物颗粒可浮选粒度上限,并且可以减少能量的消耗,这对于预选抛尾和粗粒尾矿再选,特别是对易于过粉碎的矿物浮选具有重大意义.近年来已有许多粗粒浮选技术应用于煤炭、磷酸盐矿等的选别.从分析粗颗粒矿物的性质及其难浮选的问题出发,提出了改善粗颗粒浮选的方法,总结了泡沫中浮选法、闪速浮选法、流化床浮选法等浮选方法及相关设备,并介绍了不同方法在实际生产应用中的优缺点.

Solvent extraction is the most important method for rare earth extraction and separation.Currently,di(2-ethylhexyl) phosphoric acid (HDEHP) and 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester (HEH/EHP) are widely used in industrial production,but there are still obvious deficiencies that require further research to resolve.In this paper,the unsaponification extraction of light rare earth ions in a hydrochloric acid medium by di(2-ethylhexyl) phosphoric acid-di(1-methyl-heptyl) methyl phosphonate (HDEHP-P350) system was studied.The results show that the addition of P350 reduces the extraction capacity of HDEHP,and also greatly reduces the concentration of acidity required for the back-extraction.It still has a good separation factor for light rare earths without saponification,and the extractant is not easy to emulsify.With an aqueous phase of pH =2.85,and HDEHP mole fraction XHDEHP =0.9 (compared with O/A-2),the separation effect of light rare earth is the best,resulting in the separation coefficient βCe/La =3.39,βPr/Ce =1.67 and βNd/Pr =1.45,respectively.The loaded light rare earth ions extracted by HDEHP-P350 can be easily stripped when 2 mol/L HCl is used as the stripping agent.Finally,the extraction mechanism is discussed using a slope method,and the final structure of the extracted com-plex is determined to be RECl[(DEHP)2]2P350(o),based on a combination of infrared spectra and 1H NMR and 31p NMR analyses.

方铅矿浮选抑制剂的开发和研究是铅多金属硫化矿浮选中的重点和难点.本论文提出采用硫酸溶液钝化方铅矿使其表面氧化改性并降低其表面疏水性的新方法.通过方铅矿硫酸钝化条件试验、接触角测定和X射线光电子能谱分析(XPS)等研究手段,分析了方铅矿在硫酸钝化前后的可浮性变化,确定了方铅矿最佳钝化条件,阐述了方铅矿表面酸钝化的本质.研究结果表明,方铅矿的最佳钝化条件为硫酸浓度2.0 mol/L,钝化温度100℃,钝化时间25 min.方铅矿钝化后表面接触角由93.02°减小到44.65°,表明酸钝化可有效降低方铅矿的表面疏水性和可浮性,XPS分析结果表明钝化后的方铅矿表面生成了亲水的PbSO4,导致其可浮性急剧下降.

Naturally, smithsonite and calcite have similar surface physico-chemical properties so as similar floatability, hence their separation via flotation has always been one of the difficult problems in mineral processing industry. To solve this dilemma, efficient flotation reagents which could expand the difference in surface properties could be a good bailout. In this study, guar gum was successfully employed as depressant for calcite during the smithsonite flotation, and its function mechanism were studied by micro flotation, and X-ray photoelectron spectroscopy (XPS) analysis, Fourier transform infrared (FT-IR) analysis, and Zeta potential measurement. The result of micro flotation showed that using guar gum as a depressant can effectively separate smithsonite from calcite by flotation; the analysis results of XPS, FT-IR, and Zeta potential measurements showed that the adsorption behavior of Guar gum on calcite and smithsonite was significantly different. Guar gum selectively adsorbed on the calcite surface and formed strong Ca-O chemical bond via phosphate group and hydroxide radical, which reduced the number of Ca adsorption sites on the calcite surface and thus hindered the interaction between sodium oleate and calcite surface, realizing the effective flotation separation of smithsonite from calcite.

As the most important method for the separation and purification of rare earth elements, solvent extraction is widely used in industry. HDEHP (Di(2-ethylhexyl) phosphoric acid) has become the most commonly used organic extractant because of its high separation factor for rare earth elements and large processing capacity. However, the large amount of ammonia nitrogen wastewater generated during the extraction process creates huge pressure on the environment. The tartaric acid complexing agent has been added to the aqueous phase to improve the extraction performance of HDEHP without saponification. This can effectively avoid the generation of ammonia nitrogen wastewater, which is more in line with the concept of green production. In this study, the effect of tartaric acid on the separation of Pr and Nd by HDEHP in hydrochloric acid and the corresponding mechanism are investigated. This study showed that the addition of tartaric acid could significantly increase the separation coefficient of HDEHP for Pr and Nd. When the tartaric acid concentration was 0.4 mol/L and the solution pH was 2.5, the separation coefficient reached beta Nd/Pr = 1.85, which was higher than the separation coefficient of HDEHP for Pr and Nd in the saponification system. Combining Fourier-transform infrared spectroscopy, nuclear magnetic spectroscopy other analysis and detection methods, and in-depth exploration of the extraction mechanism, the final extraction of the compound structures was determined.

Solvent extraction is the most widely used method for separation and purification of rare earth elements, and organic extractants such as di(2-ethylhexyl) phosphoric acid (P204) and di(1-methyl-heptyl) methyl phosphonate (P350) are most commonly used for industrial applications. However, the presence of impurity ions in the feed liquid during extraction can easily emulsify the extractant and affect the quality of rare earth products. Aluminum ion is the most common impurity ion in the feed liquid, and it is an important cause of emulsification of the extractant. In this study, the influence of aluminum ion was investigated on the extraction of light rare earth elements by the P204-P350 system in hydrochloric acid medium. The results show that Al3+ competes with light rare earths in the extraction process, reducing the overall extraction rate. In addition, the Al3+ stripping rate is low and there is continuous accumulation of Al3+ in the organic phase during the stripping process, affecting the extraction efficiency and even causing emulsification. The slope method and infrared detection were utilized to explore the formation of an extraction compound of Al3+ and the extractant P204-P350 that entered the organic phase as AlCl[(HA)2]2P350(o).

随着我国高品质锌资源的不断开采,高镁锌矿成为生产锌的主要来源之一.云南兰坪高镁锌矿含Zn 3.16％,含MgO 16.11％,脉石以蛇纹石和绿泥石为主.分析了抑制剂对蛇纹石、绿泥石的电化学作用机理,研究了磨矿细度、浮选药剂种类及用量对锌浮选回收降镁的影响.结果表明,当磨矿细度-45μm占90％时,以石灰、硫酸铜为调整剂,丁基黄药为捕收剂,水玻璃和六偏磷酸钠为组合抑制剂,采用"一粗一扫三精"的浮选闭路流程,最终获得了Zn品位52.53％、Zn回收率90.19％、MgO含量0.96％的锌精矿.对类似高镁锌矿的高效浮选有一定的借鉴意义.

硫化矿尾矿储量增长过快,且利用率低,造成了其堆存严重、占地面积大等问题,给社会和环境带来了极大危害,因此硫化矿尾矿的资源化利用愈发受到重视.通过综合论述硫化矿尾矿的现状和危害,阐明了硫化矿尾矿多途径利用的必要性,并根据其组分和性质特点,从作为建材原料、化工产品、尾矿再选和尾矿充填四个方面论述了硫化矿尾矿的资源化利用途径.其中,硫化矿尾矿作为建材原料可以用来生产水泥、混凝土制品、建筑用砖、微晶玻璃和陶瓷;生产的化工产品包括硫磺、工业硫酸、冶金熔剂、耐火材料和金属镁等;尾矿再选可以通过传统选矿(重、磁、浮)和生物浸出的方法来实现,缓解了矿产资源短缺的现状;尾矿充填有效避免了采空区渗漏、塌陷等安全事故.对硫化矿尾矿的资源化利用进行总结梳理,可为其后续研究提供一定参考.

锡作为现代工业不可或缺的金属,应用前景广阔.随着开采的锡矿越来越表现出贫、细、杂,以及多金属共生的特性,增加了选别技术的难度.概述了锡石选别工艺的现状,从传统重选到不同浮选工艺研究,同时介绍了浮选中捕收剂、抑制剂和活化剂的应用情况.在此基础上,展望了未来锡矿选别工艺和药剂研发的方向,为开发绿色高效选别工艺和经济实用药剂提供借鉴.