钙固化碱焙烧−水浸法从二次铝渣中分离氟和铝

设计一种钙固化碱焙烧−水浸出联合工艺处置二次铝渣,研究CaO用量、NaOH用量、焙烧温度和时间对铝溶出和氟固化行为的影响。在最佳实验条件(焙烧温度1000℃、Al与NaOH摩尔比1꞉0.6、F与CaO摩尔比1꞉2.5、焙烧时间2.0 h)下,氟和铝被分离,其中氟固化率为99.98%,铝溶出率为52.97%。水浸液经蒸发结晶,可得到符合中国工业标准的NaAlO_(2)产品;水浸渣可作为速凝水泥原料。总体而言,此研究为处置二次铝渣提供了一个有效、环保的解决方案。

Alkyl dimethyl betaine activates the low-temperature collection capacity of sodium oleate for scheelite

The impact of alkyl dimethyl betaine (ADB) on the collection capacity of sodium oleate (NaOl) at low temperatures was evaluated using flotation tests at various scales. The low-temperature synergistic mechanism of ADB and NaOl was explored by infrared spectroscopy, X-ray photoelectron spectroscopy, surface tension measurement, foam performance test, and flotation reagent size measurement.The flotation tests revealed that the collector mixed with octadecyl dimethyl betaine (ODB) and NaOl in a mass ratio of 4:96 exhibited the highest collection capacity. The combined collector could increase the scheelite recovery by 3.48% at low temperatures of 8–12℃. This is particularly relevant in the Luanchuan area, which has the largest scheelite concentrate output in China. The results confirmed that ODB enhanced the collection capability of NaOl by improving the dispersion and foaming performance. Betaine can be introduced as an additive to NaOl to improve the recovery of scheelite at low temperatures.

樟叶提取物作为新型环境友好抑制剂在白钨矿与方解石浮选分离中的应用

采用简单的物理方法,直接榨取樟叶汁液作为白钨矿和方解石分离的抑制剂。通过接触角测量、傅里叶转换红外光谱测试和原子力显微镜研究樟叶提取物中活性成分及其抑制机理。浮选试验表明,樟叶提取物对方解石有较强的抑制作用,对白钨矿的抑制作用较小。原子力显微镜检测证实方解石表面吸附有樟叶提取物的有效成分。红外光谱结果表明,吸附在方解石表面的组分含有大量的羟基,这些羟基使方解石疏水。Zeta电位和红外光谱结果表明,樟树叶提取物在方解石表面的吸附量远大于在白钨矿表面的吸附量。樟叶提取物在白钨矿和方解石浮选分离中具有潜在的应用价值。

Review of tungsten resource reserves,tungsten concentrate production and tungsten beneficiation technology in China

Tungsten is a strategic metal that is widely used in various fields such as electron communication,aeronautics and astronautics,materials and chemical engineering,due to its special properties.China has the largest reserves of tungsten resources and the largest output of tungsten concentrate in the world,and plays a decisive role in the world tungsten market.In this work,firstly,the reserves and distribution characteristics of tungsten resources in China were summarized,and the production situation of tungsten concentrate in China was reviewed.Based on the gross domestic product per capita(GDP/capita),five different annual GDP growth rates were used to estimate China’s tungsten concentrate production in the future.The estimation results suggested that if China’s economy continues to grow at the current rate,the accumulative production of tungsten concentrate will exceed current reserves by approximately 2032.Then,from the aspects of process flow,beneficiation equipment and flotation reagents,the beneficiation technology development of different types of tungsten ore in China was also reviewed,including wolframite,scheelite and tungsten-bearing slime.Finally,taking several representative tungsten mines in China as examples,the classic beneficiation technology of different types of tungsten ores was elucidated in detail.Meanwhile,the development direction of tungsten beneficiation technology in the future was put forward,which was of great significance to maintain the superiority of tungsten resources in China.

采用还原-磁化焙烧法从高铁锌焙砂中选择性浸出锌

为实现高铁锌焙砂中锌的选择性浸出,提出一种将还原焙烧与磁化焙烧相结合以强化铁酸锌选择性分解的新工艺。通过热力学分析和焙烧实验,详细研究铁酸锌的分解机理。结果表明,在8%CO(体积分数)、750℃、50%CO/(CO+CO_(2))(体积分数)和90 min的最佳还原焙烧条件下,锌焙砂中94.65%的铁酸锌被还原分解为氧化锌和氧化亚铁。随后,还原焙砂在450℃的空气气氛中磁化焙烧30 min后,焙砂中的氧化亚铁被选择性地磁化为四氧化三铁。磁化焙砂经低酸浸出后,焙砂中93.62%的锌被浸出进入溶液,而90%以上的铁以磁铁矿的形式富集在浸出渣中,浸出渣中的铁可通过磁选法进一步回收。

Synergistic depression mechanism of zinc sulfate and sodium dimethyl dithiocarbamate on sphalerite in Pb−Zn flotation system

The depression mechanism of zinc sulfate(ZnSO4)and sodium dimethyl dithiocarbamate(DMDC)as the combined depressant on sphalerite was investigated by micro-flotation experiments,ion complexing tests,contact angle tests and X-ray photoelectron spectroscopy(XPS)analysis.The micro-flotation tests revealed that ZnSO4+DMDC had a better selective depression effect on sphalerite than using single ZnSO4 or DMDC.Ion complexing tests confirmed that DMDC had a strong complexing capacity with lead ions or hydroxy complexes.Contact angle tests illustrated that ZnSO4+DMDC makes the sphalerite surface more hydrophilic than ZnSO4 or DMDC.XPS analysis indicated that the combined depressant could prevent collector adsorbing on the Pb-activated sphalerite surface by a competitive adsorption method,while the combined depressant and collector were co-adsorbed on galena surface.

Review on development of low-grade scheelite recovery from molybdenum tailings in Luanchuan, China: A case study of Luoyang Yulu Mining Company

Luanchuan area is one of the regions with the largest scale of scheelite beneficiation and the largest output of scheelite concentrate in the world. After years of innovation and progress, the beneficiation technology of low-grade scheelite associated with molybdenum tailings in Luanchuan area is becoming more and more perfect. In this study, the development process of low-grade scheelite recycling technology in Luanchuan area was reviewed, including raw ore properties, beneficiation process, flotation equipment and flotation reagents. Meanwhile, taking Luoyang Yulu Mining Co., Ltd. as an example, the effects of various technical transformations such as the optimization of the beneficiation process, the column-machine combined process, and the high-efficiency flotation reagents were elucidated in detail. However, the recycling technology of low-grade scheelite of Luanchuan area is still possible to be improved. As a result, coupled with the latest research progress, the development direction of low-grade scheelite beneficiation in Luanchuan area was also prospected. It is of great significance to further improve the recovery efficiency of low-grade scheelite resources in Luanchuan area and this can provide technical reference for other scheelite plants.

Selective depression of copper-activated sphalerite by polyaspartic acid during chalcopyrite flotation

Environmentally friendly flotation reagent,polyaspartic acid(PAPA),was tested as a potential selective depressant in the flotation separation of chalcopyrite and Cu-activated sphalerite.The depression mechanism of PAPA was revealed by contact angle measurements,Zeta potential measurements,Fourier transform infrared spectroscopy(FT-IR)analysis and inductively coupled plasma(ICP)measurement.The micro-flotation tests with single minerals showed that PAPA selectively depressed Cu-activated sphalerite,while chalcopyrite remained floatable.Moreover,a concentrate containing 31.40%Cu with a recovery of 92.43%was obtained in flotation tests of artificially mixed minerals.Results of contact angle measurements,Zeta potential measurements and FT-IR spectrum revealed that PAPA exerted a much stronger adsorption on Cu-activated sphalerite surface than on chalcopyrite surface,preventing the further adsorption of sodium diethyl dithiocarbamate(DDTC)on its surface.ICP measurements indicated that PAPA had an excellent complexing ability with Cu^(2+)in flotation pulp,weakening the activation of Cu species on sphalerite surface and producing selective depression.

Application of EDTMPS as a novel calcite depressant in scheelite flotation

In this study, the innovative use of ethylenediamine tetramethylene phosphonic sodium(EDTMPS) as a calcite depressant in scheelite flotation was investigated by flotation experiments, and its selective depression mechanism was revealed by contact angle measurement, FTIR analysis, Zeta potential test and XPS analysis. The flotation experiment results showed that scheelite and calcite could be efficiently separated under the following conditions: pulp p H=9.5, Na OL concentration of 1.5×10^(-4)mol/L, EDTMPS concentration of 3.0×10^(-5)mol/L, a scheelite concentrate with WO3grade of 65.49%, recovery of 83.29%and separation efficiency of 65.29% could be obtained from the artificially mixed minerals. The analysis results of mineral surface properties demonstrated that EDTMPS was strongly adsorbed onto the calcite surface through the reaction between the phosphonate group and the calcium ions, which hindered Na OL adsorption and increased the hydrophilicity of calcite. However, EDTMPS had weak adsorption strength on the scheelite surface, which didn’t affect further adsorption of Na OL, hence, the scheelite remained hydrophobic. Consequently, the selective adsorption of EDTMPS on the two minerals’ surfaces increased a difference in wettability and thus enabling them to be separated by flotation. Finally, the mechanism model of this flotation separation process was established.

Effect of depressants on flotation separation of magnesite from dolomite and calcite

The flotation separation of magnesite from calcium-containing minerals has always been a difficult subject in minerals processing.This work studied the inhibition effects of carboxymethyl cellulose(CMC),sodium lignosulphonate,polyaspartic acid(PASP)and sodium silicate on flotation behaviors of magnesite,dolomite and calcite,providing guidance for the development of reagents in magnesite flotation.The micro-flotation results showed that among these four depressants,sodium silicate presented the strongest selectivity due to the highest recovery difference,and the flotation separation of magnesite from dolomite and calcite could be achieved by using sodium silicate as the depressant.Contact angle measurement indicated that the addition of sodium silicate caused the largest differences in surface wettability of the three minerals,which was in line with micro-flotation tests.Furthermore,zeta potential test,the Fourier transform infrared(FT-IR)spectroscopy and atomic force microscope(AFM)imaging were used to reveal the inhibition mechanism of sodium silicate.The results indicated that the dominated component SiO(OH)3
of sodium silicate could adsorb on minerals surfaces,and the adsorption of sodium silicate hardly affected the adsorption of NaOL on magnesite surface,but caused the reduction of NaOL adsorption on dolomite and calcite surfaces,thereby increasing the flotation selectivity.

Selective depression mechanism of combination of lime and sodium humate on arsenopyrite in flotation separation of Zn-As bulk concentrate

Lime(CaO)and sodium humate(NaHA)were used as the combined depressant for arsenopyrite pre-treated by CuSO_(4) and butyl xanthate.Micro-flotation tests show that the combined depressant CaO and NaHA achieved the selective depression of arsenopyrite.Closed-circuit lab-scale test results indicate that the synergistic effect of CaO+NaHA achieved a satisfactory flotation separation of sphalerite and arsenopyrite,for which the Zn grade and recovery of Zn concentrate were 51.21%and 92.21%,respectively.Contact angle measurements,adsorption amount measurements and X-ray photoelectron spectroscopy analysis indicate that the dissolved calcium species(mainly as Ca(2+))were adsorbed on the mineral surfaces,thereby promoting NaHA adsorption.Moreover,the surface of the arsenopyrite absorbed more amount of calcium species and NaHA than that of the sphalerite,thereby accounting for the strong hydrophilic surface of arsenopyrite.The adsorption of NaHA on arsenopyrite was mainly chemical adsorption through its carboxyl groups and Ca atoms,whereas that on sphalerite surface was relatively weak.

Utilization of wastewater from zeolite production in synthesis of flotation reagents

The application of waste alkali liquids as a substitute of sodium hydroxide for the saponification to improve the collection performance of fatty acids was investigated by saponification reaction test and flotation test.The results of the saponification reaction test indicated that the optimal conditions for the saponification were stirring rate of 55 r/min,initial temperature of 40℃ and stirring time of 45 min.Meanwhile,the laboratory scale and industrial scale flotation experiments showed that the fatty acid salt synthesized by wastewater achieved an index comparable to fatty acid sodium synthesized by sodium hydroxide.As a consequence,it was feasible to replace sodium hydroxide with the wastewater from zeolite production for fatty acid saponification.The cross-border utilization of waste alkali liquids not only reduced environmental pollution,but also produced excellent economic benefits.

Cu-state evolution during leaching of bornite at 50 ℃

The bioleaching of bornite with mixed moderately thermophilic culture at 50 °C was investigated. The intermediary species formed during the leaching of bornite were characterized by XRD and XPS. In addition, the evolution of Cu-state during leaching of bornite was further studied by applying φh–p H diagram and cyclic voltammetry. The results showed that the bornite was more likely to be leached at high redox potential. Furthermore, the intermediary sulfides, such as isocubanite, covellite, chalcopyrite, disulfide, and polysulfide, were formed in the course of bornite dissolution. The Cu 2 p photoelectron spectrum revealed that the valence of copper in bornite and intermediary sulfide formed in the dissolution of bornite is ＋1. The bornite and chalcopyrite can be converted into each other, and both can be further converted to covellite and/or chalcocite.

铅锌冶炼污酸渣中重金属溶出研究

铅锌冶炼行业产生的重金属污酸渣对环境风险大,但同时也是一种可利用资源,硫酸钙基体净化是其资源化利用的第一步。本工作对污酸渣开展了全面的矿相解析,获得了污酸渣中重金属与硫酸钙的嵌布规律,并系统研究了加热时间、加热温度及硫酸浓度对污酸渣中Fe, Zn, As, Pb, Cd, Sb等关键元素浸出率的影响,系统探究了这些元素在酸性介质中的溶出规律,且基于硫酸钙晶相与介质水活度、温度的一般规律,开展了硫酸介质中常压下水活度调控致相转和高温水热致相转对元素溶出的影响。结果表明,加热时间为2 h、加热温度为80℃及硫酸浓度为.01 mol/L时效果较为理想,且在此优化溶出条件下,污酸渣中As, Zn, Sb, Cd, Fe的浸出率均可达95%以上,浸出残渣为表面光滑的薄片状和棒状的二水硫酸钙晶相;降低介质中水的活度和水热条件能够促进硫酸钙的相转,借助硫酸钙形态或晶型的转化,可进一步强化硫酸钙晶格内或晶间重金属的溶出。基于硫酸钙转晶的金属强化溶出技术是硫酸钙渣基体深度净化的有效手段。

Key technologies and development trends for efficient flotation recovery of lepidolite

Lepidolite is an essential lithium resource with diverse applications in lithium-ion batteries,ceramics,glass,and other industrial sectors.Efficient flotation of lepidolite is crucial for the extraction and recycling of lithium resources,holding significant economic and environmental importance.This review provides a comprehensive overview of the research progress on the processes,reagents,and mechanistic understanding of lepidolite flotation,grounded in the fundamental properties of lepidolite and its major gangue minerals.The article critically analyzes the current lepidolite flotation technologies and highlights the research focus on overcoming the challenge of significant fine-grained lepidolite losses during the flotation process.Through synthesis and discussion,the review also presents an outlook on the future development of lepidolite flotation technology.This comprehensive review serves as a valuable reference for advancing lepidolite flotation techniques,providing insights that enhance the efficient recovery and utilization of lithium resources,as well as the development of the new energy industry.