闪锌矿抑制剂的作用机理及研究进展

概述了闪锌矿浮选抑制剂的主要进展,分析了铅锌分离难的原因。从有机抑制剂和无机抑制剂两个方面对闪锌矿抑制剂的研究进展展开了综述,重点论述了闪锌矿抑制机理及其应用实例,并指出组合药剂以及开发新型无毒、高效、环保的浮选抑制剂的发展方向,为实现资源高效利用提供一定的指导。     

铅锌分离中锌矿物的抑制剂和活化剂及作用机理

介绍了闪锌矿的抑制剂及活化剂、异极矿和菱锌矿的活化剂及其作用机理和它们在选矿厂中的应用。通过进一步对锌矿物与药剂作用机理的研究与探索,认为研制新型高效的药剂仍是主要的研究方向。     

磨矿方式影响闪锌矿抑制剂性能的机理研究

在铜锌共生矿铜、锌浮选分离过程中,抑制闪锌矿上浮是关键。为了研究提高抑制效果的途径,通过单矿物浮选试验,利用扫描电子显微镜分析、拉曼光谱分析,研究比较了水射流磨矿与球磨磨矿(铁介质)两种不同磨矿方式对闪锌矿抑制剂作用的影响。浮选试验结果表明,无抑制剂水射流磨矿回收率大于球磨(铁介质),同时抑制剂对水射流磨矿产出的闪锌矿的抑制效果远大于对球磨(铁介质)磨矿产物的效果,说明水射流磨矿对闪锌矿天然界面保持较好,球磨(铁介质)较差。拉曼光谱分析表明,抑制剂与水射流磨矿产物中的闪锌矿作用较强,而经球磨(铁介质)磨矿,闪锌矿之间及闪锌矿表面与铁球发生反应,生成大量亲水性的羟基铁化合物,干扰了抑制剂与闪锌矿表面的作用,抑制作用显著变差。     

铜锌矿物分离中闪锌矿抑制剂的作用机理研究进展

在铜锌矿物分选中,大多采用抑制锌矿物浮选铜矿物的工艺,因此对闪锌矿抑制剂及其作用机理研究,对于提高铜锌矿浮选指标具有非常重要的意义。本文对铜锌矿物浮选分离困难的原因进行了分析,介绍了几种常用的无机抑制剂、有机抑制剂和组合抑制剂的作用机理及应用实践,并指出了研制高效、廉价、环保、无毒抑制剂是未来铜锌分离抑制剂研究发展的方向。      

组合抑制剂在硫化矿浮选过程中抑制闪锌矿的电化学机理

采用热力学计算、循环伏安测试和紫外光谱分析,研究组合抑制剂(Na2SO3+ZnSO4)对闪锌矿抑制作用的电化学行为及机理。将抑制剂Na2SO3与ZnSO4组合使用,抑制组分Zn(OH)2稳定存在的区域比ZnSO4单独使用时拓宽,由pH=11.5增大到12.5。在pH为4.00的酸性条件下,该组合抑制剂对闪锌矿的抑制作用不明显,此时组合抑制剂的加入并未阻止捕收剂DDTC与闪锌矿作用。继续增大pH值到9.18,逆向扫描过程中生成Zn(OH)2的阴极峰增大了,即大量的亲水性产物Zn(OH)2覆盖在闪锌矿的表面,阻碍捕收剂DDTC与闪锌矿进一步作用,抑制作用较为明显。当pH值增大到11.88的高碱性条件下,闪锌矿自身的氧化占据了主导地位,组合抑制剂的抑制作用不如弱碱性条件明显。加入组合抑制剂(Na2SO3+ZnSO4)后,从抑制前后紫外光谱吸收峰反射强度的差值来看,闪锌矿在中碱条件下抑制效果最好。     

组合抑制剂对硫化矿浮选过程中抑制闪锌矿的电化学机理研究

采用热力学计算、循环伏安测试和紫外光谱分析,研究了组合抑制剂（Na2SO3 ZnSO4）对闪锌矿抑制作用的电化学行为及机理。热力学及电化学分析结果表明,若将抑制剂Na2SO3与ZnSO4组合使用,抑制组分Zn(OH)2稳定存在的区域比ZnSO4单独使用时拓宽了,由之前的11.5增大到了12.5。在pH为4.00的酸性条件下,该组合抑制剂对闪锌矿的抑制作用不明显,此时组合抑制剂的加入并未阻止捕收剂DDTC与闪锌矿作用。继续增大pH值到9.18,逆向扫描过程中生成Zn(OH)2的阴极峰增大了,即大量的亲水性产物Zn(OH)2覆盖在闪锌矿的表面,阻碍了捕收剂DDTC与闪锌矿进一步作用,抑制作用较为明显。当pH值增大到11.88的高碱性条件下,闪锌矿自身的氧化占据了主导地位,组合抑制剂的抑制作用不如弱碱性条件明显。紫外光谱分析表明,加入组合抑制剂（Na2SO3 ZnSO4）后,从抑制前后吸收峰反射强度的差值来看,闪锌矿在中碱条件下抑制效果最好。     

应用分子力学法研究铜离子活化闪锌矿作用机理

用分子力学方法对Cu2＋与闪锌矿作用以及Cu2＋作用后闪锌矿表面与丁基黄药相互作用进行模拟和计算,结果表明：Cu2＋对闪锌矿起到很好的活化作用,Cu2＋在闪锌矿表面的活化机理是发生键合作用;Cu2＋活化后,丁基黄药同时吸附在闪锌矿表面Cu和Zn原子上。浮选试验和XPS测试结果验证了分子模拟所推出的结论,分子力学模拟方法可以较好解释矿物浮选作用机理。     

铅锌分离中HEDP对活化闪锌矿的抑制性能及机理研究

矿浆中的Pb²⁺会对闪锌矿的浮选行为产生较大影响,因此探究闪锌矿抑制剂对活化闪锌矿抑制效果,对于铅锌高效分离具有重要意义。拟通过单矿物浮选和人工混合矿浮选试验探究在丁基钠黄药(SIBX)体系下,铅离子对新型闪锌矿抑制剂羟基乙叉二磷酸(HEDP)抑制性能的影响,并通过Zeta电位、XPS和SEM表征手段探究HEDP在铅活化闪锌矿表面的吸附行为。单矿物浮选试验结果表明,HEDP在pH为8～11时能有效抑制铅活化闪锌矿的上浮,而几乎不影响方铅矿的浮选。人工混合矿试验结果表明,在矿浆pH=9、HEDP浓度100 mg/L、SIBX浓度20 mg/L的条件下,方铅矿的回收率高达88.21%,而闪锌矿的回收率仅有9.47%。SEM、Zeta电位和XPS分析结果表明,HEDP会与闪锌矿表面的活化产物羟基铅作用,化学吸附在被铅离子活化的闪锌矿表面,进而阻止丁基钠黄药(SIBX)在闪锌矿表面的吸附。     

方铅矿新型抑制剂BK508C及其作用机理研究

针对钼铅分离过程使用磷诺克斯抑铅浮钼存在毒性大、污染严重等问题,开展了新型环保型抑制剂BK508C替代磷诺克斯试验研究。采用单矿物浮选试验和人工混矿浮选试验的方法研究了BK508C对辉钼矿与方铅矿浮选行为的影响,并通过分子模拟、接触角测试、吸附量测定和红外光谱分析等方法研究其作用机理。单矿物浮选试验采用12.5mg/L用量的BK508C可使方铅矿的回收率降至10.82%,人工混矿分离试验分离系数达到6.32,分离效果高于磷诺克斯,说明BK508C可以替代磷诺克斯试剂实现钼铅分离。机理研究表明,BK508C与Pb_²⁺以1:1配位方式形成络合物,化学吸附在方铅矿表面,在辉钼矿表面吸附较弱,可以实现选择性抑铅浮钼。     

Investigations on different starches as depressants for iron ore flotation

Four different starches, namely soluble starch, corn starch, potato starch and rice starch with different characteristics have been studied as depressants for hematite in cationic flotation using dodecylamine as the collector. Surface charge measurement and Fourier transform infrared spectroscopy (FTIR) have been used to understand the starch–hematite interaction. The lowering of surface charge and change of peaks at 750–1500 cm⁻¹ region indicate the presence of hydrogen bonding and chemical interaction between hematite and starches. The results of flotation studies with pure minerals of hematite and quartz and a low grade iron ore at different conditions suggest that all the starches are good depressants for hematite. Maximum adsorption for all the four starches with hematite occurs at the pH value 5–9. However soluble starch is found to be the better depressant at slightly alkaline pH. The flotation of natural occurring banded iron ore using different starches has indicated that it is possible to achieve an iron grade of 63–65% Fe with 85–88% recovery.     

Characterisation of coarse composite sphalerite particles with respect to flotation

The flotation response of a typical zinc-lead (Zn/Pb) ore, with respect to coarse composite (sulphide/non-sulphide) particles is reported. The flotation tests were carried out on a selected feed particle size range (−600 + 75 μm, at P₈₀ of 390 μm) and the recovery of Zn composite particles analysed on a size by size basis. The best results were achieved with the use of 75 g/t sodium isopropyl xanthate (SIPX), obtaining a Zn recovery of 77%, with a significant improvement at the coarse end of the particle size distribution. Computerised scanning electron microscope (QEMSCAN) was used to characterise value mineral grain size and degree of liberation, as well as gangue and sphalerite association in particles reporting to both concentrate and tailings. A new characterisation function (Locking ratio, LR) was developed based on the data from the automated mineralogical analysis to characterise particles into two-phase composites with different degree of locking texture (simple and complex). The function, which is based on the mode of occurrence of sphalerite, grain size, proportion and composition of the constituent minerals in each particle, was used to study the flotation response of the particles with different degrees of locking. The results highlight the difference in recoverability of the sphalerite bearing particles with different degrees of locking, with simple locking texture giving higher recovery than complex locking texture, for the same overall liberation.     

Froth flotation of sphalerite: Collector concentration,gas dispersion and particle size effects

This experimental work on sphalerite flotation investigated the effect on flotation performance of three particle size fractions, namely, coarse (d₈₀ = 100 μm), medium (d₈₀ = 39 μm) and fine (d₈₀ = 15 μm), bubble size distribution, superficial air velocity, and collector dosage. Bubble size distributions were characterized with the image analysis technique. The two-phase (liquid–gas) centrifugal pump and frother addition (MIBC, 5–30 ppm) allowed generating bubble diameters between 150 and 1050 μm, and air holdup ranging from 0.2% and 1.3%. Main results showed that each particle-size distribution required an optimal bubble-size profile, and that sphalerite recovery proceeded from mechanisms involving true flotation (when J_g = 0.04 cm/s and 1.9 × 10⁻⁴ M SIPX). However, cluster-flotation occurs at high collector dosage (when J_g = 0.04 cm/s and d₃₂ between 285 and 1030 μm), and requiring further investigation.     

Detachment of coarse composite sphalerite particles from bubbles in flotation: Influence of xanthate collector type and concentration

The force required to detach sphalerite ore particles from air bubbles has been measured in flotation concentrates, for particles in the size range of 150–300 μm and 300–600 μm with different degrees of liberation. An electro-acoustic vibrating apparatus, that produces typical force conditions experienced in a flotation cell, was used to measure particle–bubble detachment as a function of the vibrational acceleration. Sodium isopropyl xanthate (SIPX) and potassium amyl xanthate (PAX) collectors were used in flotation, at different concentrations. At a fixed frequency of 50 Hz, the maximum vibrational amplitude at which a particle detaches from bubble was used to calculate the particle detachment force. It was shown that changes in surface hydrophobicity (contact angle), due to variations in reagent conditions have significant impact on particles detaching from bubbles. On average, detachment of particles from oscillating bubble correlated well with xanthate concentration and hydrocarbon chain length of xanthate ions. Particles (300–600 μm) with high contact angle obviously required higher force to detach from bubbles than similar particles with lower contact angle. This correlated well with the flotation response at the different reagent conditions. SEM analysis of particles after detachment showed that fully liberated particles attached to bubbles more readily and also gave higher detachment force than composite particles. Moreover larger detachment forces were observed, on average, for particles with irregular shape compared to particles with rounded shape of the same size range.     

提高云南昭通地区铅锌矿铅锌回收率的工艺技术研究

对云南昭通地区铅锌矿选矿工艺进行了研究,该矿原矿含铅２％—５％,锌９％—１４％。原生产技术指标为铅精矿品位４１．９３％、回收率７２．３９％,锌精矿品位５１．２３％、回收率６９．６９％。通过对原矿性质的研究和选矿试验,确定了磨矿粒度为７０％－２００目,改变了生产工艺流程结构,并辅以合适的硫铁矿抑制剂,将原铅、硫分选后的硫精矿进一步扫选,回收部分铅,并增加了硫精矿中回收锌的作业,所得锌粗精矿并入锌精选作业,此工艺流程应用于生产的生产技术指标为：铅精矿品位４２．８０％、回收率８０．８８％,锌精矿品位５３．６４％、回收率８１．０７％。获得了显著的经济效益。     

赤铁矿反浮选抑制剂研究

反浮选是提高铁精矿品位的有效方法,而抑制剂的选用是影响反浮选工艺的关键因素,本文从最常用的淀粉抑制剂入手,阐述了赤铁矿反浮选抑制剂的研究进展,综合分析了天然高分子和有机合成高分子各自的优缺点。结合有机小分子螯合抑制剂选择性好的特点以及聚合物分子量具有可控性的特点,有望研制大分子有机抑制剂以替代淀粉作为赤铁矿反浮选抑制剂,其前景较为光明。     

闪锌矿磨矿浮选过程中电化学研究进展

闪锌矿作为提炼锌的主要矿物原料,是重要的锌矿石,但由于其复杂的共伴生关系,制约了闪锌矿的高效开发和利用。闪锌矿属硫化物矿物,具有半导体特性,在磨矿和浮选过程中的电化学特性显著。闪锌矿晶体中金属杂质的改变、磨矿环境和浮选溶液环境的改变,都会改变闪锌矿矿物表面的电化学性质,进而影响闪锌矿的分离与富集,了解闪锌矿电化学机理,改变闪锌矿电化学条件,可使闪锌矿的浮选朝着有利方向进行。本文对近几年国内外闪锌矿电化学机理研究进行文献综述,通过对闪锌矿磨矿和浮选过程中的电化学特性进行分析研究,为闪锌矿电化学机理的后续研究提供了理论支持,对进一步提高含锌资源的综合利用和开发提供理论依据,也对其它具有导电性能的硫化物矿物的研究提供了新的方法和理论。     

镍黄铁矿浮选中抑制剂的作用

介绍了蛇纹石对镍黄铁矿浮选的影响,解释了几种常用抑制剂的作用机理。六偏磷酸钠和水玻璃主要通过生成亲水性的配合物,改变蛇纹石的表面电性而起分散和抑制作用;羧甲基纤维素主要通过氢键有与蛇纹石表面的金属离子发生化学吸附而起絮凝和抑制作用;提出了在镍黄铁矿浮选中选用抑制剂的研究思路。     

The role of calcium in xanthate adsorption onto sphalerite

This paper presents results of a laboratory study designed to look into the effect of calcium on sphalerite hydrophobization with xanthate making use of zeta potential, contact angle, microflotation and UV/vis spectrometry techniques. The experimental results show that xanthate adsorbs onto the mineral surface at neutral and slightly acid pH as reflected by contact angle, floatability (by microflotation) and xanthate adsorption (by UV/vis spectrometry) measurements. Apparently, xanthate adsorption is due to both the less negative surface charge of the mineral and to the presence of Zn²⁺ in equilibrium with the mineral, rather than Zn(OH)₂, which is the product of the mineral oxidation with dissolved oxygen at pH above 8. When calcium is present in the aqueous solution at concentrations similar to that of saturation for gypsum precipitation (e.g., about 0.017 mol/L), calcium apparently adsorbs on the sphalerite surface decreasing its negative charge (e.g., zeta potential) and promoting xanthate adsorption and hydrophobization, as reflected by contact angle and floatability measurements (ca. 30° and 33% recovery, respectively). Calcium adsorption appears to be favoured by the increase in pH, as reflected by the increased xanthate adsorption, thus suggesting that the calcium hydroxo-complex (CaOH⁺) is the adsorbing species. At pH 10 and 11, precipitation of calcium hydroxide (observed by SEM-EDS measurements at pH 11) appears to counteract xanthate adsorption, substantially decreasing mineral hydrophobicity. Calcium and xanthate appear to display some type of chemical interaction while calcium and dithiophosphinate do not.