白铅矿的硫化电位控制浮选机理研究

以乙基黄药为捕收剂,硫化钠为硫化剂,通过单矿物浮选试验系统地研究了白铅矿浮选时硫化钠用量、硫化时间、搅拌条件、加药方式以及矿浆p H对硫化过程中矿物的浮游性、矿浆电位、硫离子电极电位的影响。采用多元回归方法建立了浮选回收率与硫化电位的数学模型,数学模型很好地反映了两者之间的关系。使用相关系数法分析了各因素对硫化电位的影响趋势及两者间的相关性。利用Matlab数学软件拟合出硫化电位与主要影响因子间的数学模型方程,再结合回收率与电位的数学模型,可以实现对硫化过程及时、合理的调控。     

白铅矿、褐铁矿的硫化浮选试验研究

详细研究了硫化钠用量、矿浆pH值、硫化时间以及pH调整剂种类对白铅矿和褐铁矿浮选的影响,重点考察了乙基黄药、丁基黄药、异丁基黄药、戊基黄药和异戊基黄药五种黄药的捕收性能。试验结果表明,在适宜条件下白铅矿经过硫化后具有很好的可浮性,而褐铁矿则很难被硫化,可浮性较差;异丁基黄药浮选白铅矿效果最好。褐铁矿含量影响白铅矿的浮选回收率,褐铁矿含量越高,白铅矿浮选回收率越低。     

白铅矿硫化浮选体系的电化学性质研究

针对白铅矿的硫化浮选体系, 研究了硫化钠用量、乙黄药用量、硫化时间、矿浆酸碱度、叶轮搅拌速度、加药方式等工艺参数对浮选回收率、矿浆电位和硫离子电极电位的影响。结果表明, 合适的硫化钠用量是实现白铅矿浮选的关键, 在矿浆电位为-380~-10 mV、硫离子电极电位为-640~-320 mV时, 白铅矿回收率可达90%以上。采用矿浆电位和硫离子电极电位监测白铅矿的硫化过程在理论上是可行的。     

氧化铅矿石硫化浮选工艺研究

针对某铅锌矿处理的高氧化率复杂铅锌矿石中的氧化铅矿石,进行了硫化浮选工艺的研究。浮选采用Na2S作为氧化铅的硫化药剂。研究结果表明,采用硫化浮选技术获得的铅精矿品位达到46.02%、铅回收率达到81.16%,实现了氧化铅矿物的高效回收。     

白铅矿浮选体系中硫化钠作用机理研究

本文采用XPS、XRD和SEM研究了白铅矿经硫化钠处理后的表面状态,表明矿物表面有PbS薄膜的存在,结合浮选试验探讨了乙基黄药浮选体系中硫化钠的作用机理.研究表明,PbS薄膜的生成活化了白铝矿.     

菱锌矿表面硫化研究进展

氧化锌矿和硫化锌矿是锌资源的主要组成部分,随着锌需求的不断增长及硫化锌矿资源的日益消耗,氧化锌矿的高效利用将成为解决锌资源匮乏问题的重要手段,而菱锌矿作为氧化锌矿物的典型代表,被广大科研工作者关注和研究。近年来,硫化浮选法被广泛应用于处理氧化锌矿,故硫化是该工艺的关键环节。在前人研究的基础上,本文详细归纳和分析了菱锌矿的表面硫化机理及影响硫化的主要因素,并详细阐述了强化菱锌矿表面硫化的方法,指出在今后的研究中,应借助多学科交叉及各先进检测分析手段完善菱锌矿的表面硫化机理和强化硫化机制。同时,研发高效硫化-绿色清洁的新型高效浮选技术有助于选矿工作者们更好地从事生产实践。     

白铅矿,菱锌矿晶体化学性质与硫化行为

本研究采用红外光谱、俄歇电子能谱、X 射线光电子能谱、X 射线衍射等手段测定了白铅矿、菱锌矿硫化表面产物.结果表明,白铅矿经硫化剂作用后,其解离表面存在 PbS、PbSO_4和碱式碳酸盐.这些化合物并非单纯以化学吸附的方式存在,还可通过 S~(2-)离子与 CO_3~(2-)离子发生交换反应而进入晶格,在白铅矿表面形成了以 PbS 为主要成分的结晶膜.菱锌矿只有在加温硫化的情况下才能有效地形成以 ZnS 为主要成分的结晶膜.菱锌矿解离面上 CO_3~(2-)对 Zn~(2+)离子的屏蔽作用对其表面的硫化有一定的影响.     

白铅矿表面硫化及黄药吸附的密度泛函理论研究

硫化-黄药法是浮选白铅矿的主要方法，为探究硫化对白铅矿表面结构的影响，采用基于紧束缚法的密度泛函理论对乙黄药、丙黄药和丁黄药在白铅矿(001)表面的吸附进行模拟。结果表明，3种烃基黄药类捕收剂会与清洁白铅矿(001)表面发生化学吸附，并且随着碳链长度增长，吸附作用更强；水化作用会增大药剂分子在矿物表面的吸附距离，导致黄药与水化白铅矿(001)表面基本不发生化学吸附；硫化后的白铅矿(001)表面会与黄药发生吸附，且吸附作用明显增强。研究结果可为实现白铅矿的高效浮选提供理论指导。     

硫化矿浮选机理的量子化学研究进展*

以硫化矿浮选机理的量子化学研究历程为主线,从浮选剂与硫化矿作用机理研究、矿物表面特性研究以及采用的量子化学研究方法的变革等三个方面,简要评述了我国硫化矿浮选机理的量子化学研究现状及发展方向。     

硫化矿物浮选理论基础

本评述的目的是为了对硫化矿物的浮选效果进行预测和根据实验室试验进行按比例放大。化学参数和物理参数之间的交互作用和不平衡影响使完成这些任务更为困难。硫化矿物从开采到破碎的磨矿，一直到以精矿离开浮选槽的过程中都发生着物理变化和化学变化。本文对这变化进行了叙述。讨论了近年来新发明的测试技术，鉴定和估计矿物表面组分数量的优点。     

Calculation of the specific surface area in flotation

Different weighting functions for calculating the specific surface area and average bubble diameter in froth flotation have been studied. The weighting functions considered were number, length, area and volume. Using bubble size distribution data obtained from image processing of batch flotation froth, specific surface area and average equivalent diameter were calculated. It was found that weighting by surface area was the most appropriate method to determine both specific surface area and average equivalent diameter. The equivalent ellipsoidal diameter was found to be a more appropriate average diameter than the equivalent spherical diameter.     

2021年浮选药剂的进展

收集了2021年国内核心期刊发表的部分浮选药剂的信息,分硫化矿捕收剂、氧化矿捕收剂、调整剂、起泡剂、浮选药剂的结构与性能,及废水处理五个方面介绍并略加评论.     

镍黄铁矿无捕收剂浮选行为及表面氧化电化学研究

研究了镍黄铁矿在无捕收剂条件下浮选行为及表面氧化电化学过程。单矿物浮选和循环伏安曲线结果表明,在4.0＜pH＜11.0时,镍黄铁矿表面容易发生适度氧化生成大量疏水性单质硫,使矿物表面疏水实现无捕收剂可浮,其对应的电位区间为110~386mV。在强碱条件下,镍黄铁矿表面前期氧化生成的疏水性单质硫易深度氧化为高价亲水硫化物致钝层,阻碍电化学反应的继续进行,使镍黄铁矿无捕收剂可浮性差。     

煤泥浮选气泡比表面积的计算方法

为了从基于分水岭变换分割后的煤泥浮选泡沫图像上获得更加准确的气泡大小的分布情况,需要计算气泡的比表面积.由于气泡的不规则性,使用等效椭圆比等效圆来计算面积、体积更能反应真实的气泡情况.通过对比表面积进行不同的加权,比较表明,使用气泡投影的横截面积作为加权系数是描述气泡分布情况最适合的方法.同时还讨论了气泡特征与浮选操作条件之间的关系,为计算机在线控制浮选过程建立基础.     

Estimation of the actual bubble surface area flux in flotation

The bubble surface area flux, S_B, defined as the ration between the superficial gas rate J_G and the Sauter mean bubble diameter D₃₂, has been widely used to describe the gas phase dispersion efficiency in flotation machines, and from this predict flotation performance, notable mineral recovery to forecast plant economics.In this work, results of bubble size distribution (BSD) generated in a pilot column are analyzed. Using video and image analysis techniques, the impact of different sampling rates on the BSD was evaluated. Measurements were carried out for D₃₂ = 1–2 mm, J_G = 0.5–1.5 cm/s and two frother concentration, with a maximum sampling rate of 100 fps. In addition, the bubble rise velocity in the bubble swarm was measured, as a function of the individual bubble diameter, for different operational conditions.The identification of the BSD depends on the proper selection of the visual field and sampling rate for acquisition and processing of bubble images. Distortion in the estimation occurs because a larger holdup of small bubbles is observed, relative to the overall data set, due to their lower velocity.The actual BSD was obtained by correcting the observed population, considering the effect of bubble rise velocity. Thus, the actual bubble surface area flux, S_B, was calculated. The results were evaluated at a pilot scale (air–water system) as well as an industrial plant scale (air-pulp system).     

Study on the flotation behaviour of low energy materials at low surface tensions

Surface tension is one of the most important factors in a flotation process, normally being understood to mean surface tension at the pulp surface. In most cases this is enough, but when we try to process materials which have low surface energies, we also have to take into account the surface tension between the air bubbles and the liquid (water) in the flotation cell. This paper reports preliminary study results on this subject.     

Spectroelectrochemical investigations of flotation reagent–surface interaction

Surface enhanced Raman scattering (SERS) spectroscopy at surfaces under electrochemical control has been applied to elucidate the adsorption of thiol collectors. SERS spectroelectrochemical studies at coinage metal electrodes have been carried out on ethyl xanthate, and three isoxanthates, O-isopropyl-N-ethylthionocarbamate, 2-mercaptobenzothiazole, diisobutyldithiophosphinate and butylethoxycarbonylthiourea. For each collector, adsorption occurs via charge transfer to form a metal–sulfur bond and, in situations for which the reversible potential of the formation of the bulk phase is known, at underpotentials. Mercaptobenzothioazole was detected on chalcopyrite after immersion in a solution of the collector after the deposition of gold to induce SERS.     

A model to relate the flotation rate constant and the bubble surface area flux in mechanical flotation cells

Two recent flotation models developed by the authors are discussed, viz. the bubble population balance model and the attachment-detachment model. The bubble population balance model describes the history of a bubble population in a flotation cell in terms of the sub-processes of bubble breakage and coalescence. The attachment-detachment model allows for the presence of a gas phase in the flotation cell, both in terms of a gas residence time and the attachment and detachment of mineral particles to/from bubbles. When combined the two models predict a near-linear region about a point of inflexion on the (simulated) response between the flotation rate constant (k) and the flux of bubble surface area through the flotation cell (S_b). It is proposed by the authors that this region corresponds to the linear k−S_b relationship observed in a recent research project on flotation kinetics in mechanical flotation cells by Gorain et al. (1997).