硫化矿物硫化钠诱导浮选的电化学研究

本文研究了黄铜矿，黄铁矿的硫化钠诱导浮选行为。浮选实验，电化学研究表明，黄铜矿表现出较差的硫化钠诱导浮选行为，而黄铁矿则很好。硫化钠诱导浮选机理是由于ＨＳ－离子在矿物表面氧化产生疏水性的元素Ｓ０所致；硫化矿表面静电位的高低决定了ＨＳ－氧化成Ｓ０的可能性，黄铁矿表面静电位Ｅｍｓ高于ＨＳ－氧化成Ｓ０的电极电位，因而黄铁矿表现出良好的硫化钠诱导浮选特性；黄铜矿表面静电位低于这一电极电位，因而硫化钠诱导浮选性较差。     

无捕收剂浮选的电化学及量子化学研究

本文给出了有无硫化钠存在时。黄铜矿和黄铁矿的无捕收剂浮进行为。研究表明,黄铜矿自诱导浮选良好,有较宽的电位和pH范围;弱酸性和碱性介质中,黄铁矿自诱导浮选较差,没有电位范围。硫化钠的添加,明显促进了黄铁矿的无捕收剂浮选,黄铁矿有良好的硫化钠诱导浮选。对天然矿石验证试验表明,自诱导浮选技术能够有效分离黄铜矿和黄铁矿。通过HS~-离子吸附量的测定,矿物表面中性硫量提取分析、电化学测试和量子化学计算,较详细研究了黄铜矿和黄铁矿无捕收剂浮选的机理,矿物表面中性硫是主要疏水体。     

方铅矿诱导浮选研究

详细地考察了方铅矿和黄铁矿的诱导浮选行为。研究表明，方铅矿的自诱导可浮性良好，黄铁矿则很差。黄铁矿的适量硫化钠条件下，具有良好的硫诱导可浮性。与捕收剂诱导相比，自诱导或硫诱导均使铅硫的可浮硫的可浮性差异增大，同时浮选分离的范围也加宽。据此，对方铅矿和黄铁矿浮选分离进行了方案设计。人工混和矿试验表明，诱导浮选技术能够有效地分离方铅矿与黄铁矿。     

方铅矿诱导浮选研究

详细地考察了方铅矿和黄铁矿的诱导浮选行为，研究表明，方铅矿的自诱导可浮性良好，黄铁矿则很差。黄铁矿在适量硫化钠条件下，具有良好的硫诱导可浮性。与捕收剂诱导相比，自诱导或硫诱导均使铅硫的可浮性差异增大，同时浮选分离的范围也加宽。据此，对方铅矿和黄铁矿浮选分离进行了方案设计。人工混和矿试验表明，诱导浮选技术能够有效地分离方铅矿与黄铁矿。     

硫化铜矿诱导浮选的研究与应用

考察了黄铜矿和黄铁矿的诱导浮选行为，并对其机理进行探讨。研究表明，黄铜矿具有良好的自诱导可浮性；黄铁矿的自诱导可浮性差，但具有良好的硫化钠诱导可浮性。不同的诱导浮选特性可以使硫化铜矿的铜硫分离更具选择性。     

无捕收剂浮选的半导体能带理论讨论

用量子力学计算得到了方铅矿(PbS)和黄铁矿(FeS_2)的半导体能带图,以及分子氧和HS-离子的HOMO和LUMO的能量。计算结果画成方铅矿和黄铁矿半导体与分子氧和HS-离子作用的能级图,从电子转移微观层次上解释这两类矿物的无捕收剂浮选机理(包括自诱导浮选和硫化钠诱导浮选)。结果表明,P型半导体(以黄铁矿为典型代表)具有良好硫化钠诱导浮选行为,N型半导体(以方铅矿为典型代表)具有良好自诱导浮选行为。电子载流子浓度(n_e)与空穴载流子浓度(n_p)之比值可以作为一个参数来判断无捕收剂浮选行为:n_c/n_p值大,自诱导浮选行为好;n_p/n_e值大,硫化钠诱导浮选行为好。     

硫化矿－溶液界面电子转移的前线分子轨道理论讨论

本文通过半经验分子轨道法（ＣＮＤＯ／２）计算，得到了方铅矿和黄铁矿表面的电子结构、原子净电荷密度和前线分子轨道能量。用前线分子轨道理论探讨了电子在硫化矿－溶液界面转移的微观机理。硫化矿自诱导浮选涉及到电子从矿物表面转移到分子氧；硫化钠诱导浮选涉及到电子从ＨＳ－离子传递给矿物表面然后再给分子氧。研究表明，方铅矿表面电子能级较高，易给出电子，自诱导浮选好，黄铁矿表面电子能级较低，易接受电子，硫化钠诱导浮选好。     

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.     

硫化钠作还原剂硫化矿物无捕收剂浮选规律及分离方案的设计

硫化钠作为一种还原电位调整剂,在硫化矿物无捕收剂浮选中起着特殊作用。它能促进黄铁矿和毒砂的无捕收剂浮选,能抑制黄铜矿和方铅矿的无捕收剂浮选,从而表现出不同于其它常用还原剂(如S_2O_4~(2-)、SO_3~(2-))的特殊性能。通过控制硫化钠浓度来调控矿浆电位,实现硫化矿物之间的无捕收剂浮选分离。本文以黄铜矿、方铅矿、毒砂、黄铁矿和闪锌矿为例,设计了硫化钠存在下无捕收剂浮选分离的方案。这是一种新的浮选分离思想,可供硫化矿物浮选分离研究及生产实践参考。     

黄铁矿自诱导电化学浮选研究

研究了不同pH条件下黄铁矿的自诱导电化学浮选行为，并从电化学角度讨论了黄铁矿自诱导浮选机理。     

乙硫氮作捕收剂时无机调整剂加药顺序对典型硫化矿物浮选的影响

研究了乙硫氮作捕收剂时无机调整剂硫酸锌、亚硫酸钠、硫化钠和硫酸铜不同加药顺序对典型硫化矿物黄铜矿、方铅矿、闪锌矿和黄铁矿浮选行为的影响。结果表明,调整剂与捕收剂的加药顺序对硫化矿物浮选的影响不同。与调整剂先加时相比,乙硫氮先加时,硫酸锌对黄铜矿和方铅矿浮选的抑制作用减弱;硫酸锌、低用量硫酸铜、亚硫酸钠或硫化钠对闪锌矿浮选以及硫酸铜对黄铜矿和方铅矿浮选的抑制作用更强;硫酸锌或硫酸铜对黄铁矿浮选以及较高用量硫酸铜对闪锌矿浮选的活化作用相当;亚硫酸钠或硫化钠对黄铜矿、方铅矿和黄铁矿浮选的影响很小。研究结果可为部分硫化矿通过改变调整剂与捕收剂的加药顺序提高矿物浮选分离效率提供借鉴。     

会泽铅锌硫化矿异步浮选新技术研究

通过单因素和正交浮选试验研究了会泽方铅矿、黄铁矿与闪锌矿之间的浮选分离。根据浮选动力学基本原理,对方铅矿和黄铁矿的浮选动力学特性进行了分析。结果表明,基于总体平衡理论的分速浮选模型可以较好地模拟方铅矿和黄铁矿的浮选过程,浮选回收率模型拟合值与试验值之间的相关系数R2均达到0.999。研究认为,异步浮选新技术充分利用不同矿物及同种矿物可浮性和浮游速度特性,实现矿物的个性化、差异性浮选。进一步探讨了异步浮选新技术的理论背景,对选矿人员完善已有工艺及开发新技术具有一定的参考意义。     

乙硫氮作捕收剂时有机调整剂加药顺序对典型硫化矿物浮选的影响

研究了乙硫氮作捕收剂时有机大分子调整剂糊精、腐殖酸钠、阳离子瓜尔胶和DP115(改性聚丙烯酰胺有机大分子)不同加药顺序对典型硫化矿物黄铜矿、方铅矿、闪锌矿和黄铁矿浮选行为的影响。单矿物浮选试验结果表明,有机大分子调整剂与捕收剂乙硫氮的加药顺序对硫化矿物浮选的影响不同。与调整剂先加时相比,乙硫氮先加时,糊精对黄铜矿、方铅矿和闪锌矿浮选的抑制作用更强;腐殖酸钠对黄铜矿和方铅矿浮选的抑制作用不同程度增强,较低用量腐殖酸钠对闪锌矿浮选的抑制作用减弱,而较高用量时则强烈抑制闪锌矿;阳离子瓜尔胶对黄铜矿和方铅矿浮选的抑制作用减弱,对闪锌矿浮选的抑制作用略强;DP115对黄铜矿浮选的抑制作用减弱,低用量DP115对方铅矿浮选的抑制作用相当而对闪锌矿浮选的抑制作用减弱,较高用量时对方铅矿浮选的抑制作用更强而对闪锌矿浮选的抑制作用相当;糊精、腐殖酸钠、阳离子瓜尔胶和DP115对黄铁矿浮选的影响很小。研究结果可为部分硫化矿通过改变有机大分子调整剂与捕收剂的加药顺序提高矿物浮选分离的选择性和效率提供借鉴。     

Selective depression of pyrite with chitosan in Pb–Fe sulfide flotation

Chitosan was used in the flotation of pyrite–galena mixtures. The results indicated that chitosan preferentially adsorbed on pyrite and galena was floated from the pyrite–galena mixtures. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) and X-ray photoelectron spectroscopy (XPS) analyses were performed to study the interaction mechanism of chitosan on the pyrite and galena minerals at pH 4 and 6. ToF-SIMS showed that chitosan adsorbed heavily on pyrite but barely on galena when a mixture of pyrite and galena was treated by chitosan. The high resolution XPS spectra indicated that both the amine and the hydroxyl groups from chitosan reacted with pyrite surface, whereas no significant binding energy shifts were observed on galena. Combined with the authors’ previous studies of chitosan in other sulfide flotation systems, it was observed that chitosan could depress pyrite, galena, sphalerite and chalcopyrite to different extent when the minerals were floated alone. However, in the flotation of mineral mixtures, chitosan selectively adsorbed on one mineral which depressed its flotation, allowing the other mineral to be floated from the mixture. The competitive adsorption was attributed to the differences in the electron affinity value of the lattice metal ions. Chitosan strongly binds with metal ions with a high electron affinity.     

Comprehensive recovery of metals from cyanidation tailing

Cyanidation tailing is the residue produced in gold plants which use cyanidation to extract gold. It can be used as a secondary resource to recover residual metals that are of great economic value. The cyanidation tailing investigated in this paper was obtained from Shandong Province, China. It contained valuable metals such as chalcopyrite, galena, sphalerite and pyrite. In this study, alkaline sodium hypochlorite was used as a regulator in the pretreatment stage. It was proved that the sodium hypochlorite played two roles in the flotation pulp: oxidant and pH regulator. On one hand, sodium hypochlorite oxidized cyanide to cyanate, eliminating the negative effect of residual cyanide towards the environment. On the other hand, with the pH of flotation pulp exceeding 10, sphalerite and pyrite were depressed enormously, which was beneficial to the recovery of chalcopyrite and galena. With the Cu–Pb bulk flotation flowsheet, the cyanidation tailing was processed to obtain qualified Cu concentrate with grade of 13.17% and recovery of 70.00% compared with the original Cu grade of 0.21%. The Cu–Pb tailing was processed to obtain qualified Zn concentrate with grade of 34.72% and recovery of 69.58% compared with the original Zn grade of 0.33%, constituting the comprehensive recovery routing for the cyanidation tailing.     

Combinations of different-class collectors in selective sulphide-ore flotation

The paper discusses laboratory test data on well-known sulphydryl collectors and new modified dithiophosphates Beraflot used to float monomineral fractions of pyrite, chalcopyrite, galena, and sphalerite. Frothless flotation is employed in flotation tests, IR-spectroscopy is used to identify surface compounds, and technological investigations are based on froth flotation. It is shown that dimethyl dithiocarbamate, isobutyl dithiophosphate and modified collector Beraflot-3035 give the poorest results of pyrite flotation, while Beraflot-3035 provides the highest galena and chalcopyrite recovery. It is found that Beraflot-3035 is capable to form different surface compounds on pyrite, chalcopyrite, galena, and sphalerite. Unclosed ore tests verify selectivity of Beraflot-3035.     

Dispersion effect on a lead–zinc sulphide ore flotation

This investigation was performed with samples from a lead–zinc sulphide deposit aiming at studying the influence of the dispersion degree of the particles in the pulp on lead and zinc flotation. Samples of ore and also of the minerals sphalerite, galena, pyrite, and dolomite were selected for the experiments. Nine types of dispersing agents and six blends among them were employed.A set of three dispersing agents was selected for the lead flotation and another set of three was chosen for zinc flotation. The criteria for the reagents selection were: high dispersion degree for galena and low for the other species, high dispersion degree for sphalerite and low for the other species, low dispersion degree for pyrite and high for the other species, and high dispersion degree for all species.Lead flotation experiments were performed under three conditions aiming at verifying the influence of the dispersing agent, of the pH, and of sodium carbonate. The zinc flotation tests were carried out at pH 10.5, modulated with lime.The use of dispersing agents in lead flotation did not improve the overall efficiency of the circuit for, despite improving the lead metallurgical recovery, they increase significantly the zinc losses in the lead concentrate.Sodium carbonate presented a low dispersion degree and did not affect the lead flotation results when compared with those achieved at natural pH and at pH 9.8 modulated with lime.Two dispersing agents were particularly effective in zinc flotation: dispersant 3223, a sodium polyacrylate, and sodium hexametaphosphate. Both reagents significantly enhanced zinc recovery without impairing the concentrate quality.     

磨矿过程硫化矿物表面电化学性质及其对浮选的影响

本文根据浮选电化学理论分析讨论了丁黄药和乙硫氮在方铅矿、闪锌矿及黄铁矿三种硫化矿物表面的电化学作用过程,分析了磨矿环境具有低电位还原气氛产生的原因。腐蚀电偶测定结果表明,磨球介质与硫化矿物之间、方铅矿与黄铁矿之间的原电池相互作用减弱了黄铁矿表面的捕收剂作用过程,有利于方铅矿与黄铁矿的浮选分离。浮选试验结果表明利用磨矿过程进行浮选的工艺有较大的优越性     

云南某硫化铅锌矿工艺矿物学及选矿试验研究

针对云南某硫化铅锌矿,方铅矿嵌布粒度细、黄铁矿含量高的特点,进行了工艺矿物学与浮选回收技术研究。采用铅硫混浮-混合粗精矿再磨-铅硫分选-锌硫分选选矿回收工艺,基于全流程主要条件试验确定最佳工艺技术条件。实验室全流程闭路试验获得了Pb品位65.52%,Pb回收率87.51%,含锌3.89%的铅精矿;锌1,锌2合计Zn品位54.74%,Zn回收率95.02%的锌精矿及Fe品位42.02%,Fe回收率78.26%硫精矿。目的矿物方铅矿、闪锌矿和黄铁矿均得到良好回收。     

超声波预处理对不同体系中方铅矿浮选行为的影响

借助浮选试验、ICP-OES和XPS检测分析, 系统研究了不同体系中超声波预处理对方铅矿浮选行为的影响规律。结果表明, 对方铅矿和黄铁矿分别进行超声波处理时, 能有效促进矿物表面氧化成分的溶解, 暴露出新鲜表面, 使矿物可浮性明显提高。方铅矿和黄铁矿混合后进行超声波处理时, 会促进两种矿物之间的电化学反应, 使方铅矿表面氧化加深, 生成硫酸铅沉淀, 从而导致方铅矿可浮性降低, 尤其是对表面洁净的两种矿物混合后进行超声波处理时, 方铅矿可浮性进一步降低。此外, 方铅矿和黄铁矿之间的电化学反应程度还会因两者不同粒级引起的表面积比率的变化而产生较大差异, 进而影响方铅矿的可浮性。