氧化预处理对铜钼浮选分离效果的影响

以NaClO或H₂O₂为氧化剂,研究了氧化对铜钼浮选分离试验效果的影响。探究了氧化剂用量、氧化时间和矿浆pH值等因素对黄铜矿和辉钼矿可浮性的影响以及作用机理。单矿物浮选实验结果表明,NaClO或H₂O₂氧化处理均可选择性抑制黄铜矿,且几乎不影响辉钼矿的可浮性。混合矿浮选实验结果表明,NaClO或H₂O₂氧化预处理-浮选都能实现铜钼有效分离,且分离效果均优于传统的黄铜矿抑制剂硫化钠。接触角测量结果表明,NaClO或H₂O₂氧化处理都可选择性地使黄铜矿表面亲水。Zeta电位和XPS分析结果表明,黄铜矿表面变得亲水是因为氧化处理后矿物表面生成了不溶于水的亲水性氧化物和氢氧化物。     

The use of canola oil as an environmentally friendly flotation collector in sulphide mineral processing

The efficiency of mineral flotation relies on the ability to selectively recover different value minerals into their respective concentrates at optimum grades and recoveries based on the differing hydrophobicities. Many of the common hydrophobizing reagents (collectors) currently used in flotation have significant occupational and environmental implications, and hence there is a quest for environmentally benign chemical additives that give similar or better performance than the more toxic conventional reagents. In this paper, we provide substantial experimental evidence that the use of edible, fatty acid-based oils (canola and palm) can foster the flotation recovery of chalcopyrite and molybdenite minerals more selectively against pyrite than the conventional collectors, sodium isopropyl, potassium amyl xanthates and diesel oil.Single and mixed chalcopyrite/pyrite minerals and plant sulphide ores’ flotation studies using canola and palm oils, in contrast with conventional collectors, are reported herein. The results indicate greater efficacy of the canola and palm oils in comparison with the conventional collectors for chalcopyrite and molybdenite recoveries and product upgrades. This is believed to be due to the edible oils’ specific interactions with iron oxides sites preferentially formed in situ on the surfaces of the chalcopyrite or molybdenite in the pulp rather than on the pyrite surfaces, causing limited recovery of the pyrite. Complementary contact angle results confirmed that more canola oil is adsorbed onto chalcopyrite surfaces than onto pyrite surfaces. For the mineral mixtures tested, the edible oil’s degree of unsaturation had a noticeable effect on its performance as a collector. A higher pyrite recovery and slightly lower chalcopyrite grade was obtained with palm oil than with canola oil. These findings suggest that the use of canola oil has a potential to add to the existing array of flotation collectors and would represent a combined opportunity for both the mining and agricultural sectors, with concomitant health, environmental and economic benefits.     

Cu-S flotation separation via the combination of sodium humate and lime in a low pH medium

The flotation separation of chalcopyrite and pyrite was studied in the presence of sodium humate. The results of flotation tests indicated that pyrite can be selectively depressed by sodium humate, and the activity of sodium humate was strongly affected by the pH of the pulp. At high pH values, pyrite was strongly depressed by sodium humate; however, the content of chalcopyrite was not affected. Ore flotation tests were successfully conducted in the laboratory and at the Dexing Copper Mine by applying sodium humate as a pyrite depressant. By adding 40-60 g/t of sodium humate to the pulp and adjusting the pH to 10-10.5 with CaO, a concentrate with a Cu content of 24% was obtained without reducing the Cu recovery rate. In addition, the dosage of CaO was reduced, and the recovery of Au, Ag and Mo in the copper concentrate was enhanced due to the reduced pH of the pulp. The zeta potential, adsorption of xanthate and contact angle of the mineral surface were measured, and the results from surface measurements indicated that there was a strong hydrophilic interaction between sodium humate and the surface of pyrite. Moreover, the results revealed that the interaction between sodium humate and chalcopyrite was weak. Infrared (IR) spectra of pyrite and sodium humate were obtained, and the results indicated that sodium humate was chemically adsorbed on the surface of pyrite.     

Adsorption of tailored carboxymethyl cellulose polymers on talc and chalcopyrite: Correlation between coverage,wettability, and flotation

A carefully chosen selection of CMC polymers was used to probe the depression of talc and chalcopyrite and to highlight the effect of specific alterations of the bulk polymer chemistry on the power and selectivity of the depressants. In situ tapping mode atomic force microscopy (AFM), captive bubble contact angle measurements, and flotation tests were used to study the adsorption of the CMC polymers on chalcopyrite and talc. The degree of substitution and distribution of substitution of carboxymethyl groups on CMC was seen to have a strong influence on the ability of the polymers to adsorb onto the surface of talc and chalcopyrite. High substitution results in low coverage on both minerals whereas low substitution results in higher coverage. The influence of distribution of substitution (random or clustered) was also seen to affect the adsorption, with more random/even substitution giving rise to greater adsorption on talc and chalcopyrite. The contact angle of talc and chalcopyrite is significantly altered in the presence of the three polymers, with increased surface coverage (determined by AFM) correlating with the ability of the polymers to decrease the wettability of talc and chalcopyrite. This trend was also followed in single and mixed mineral talc and chalcopyrite flotation.     

一种新型辉钼矿抑制剂及其在铜钼浮选分离中的机理研究

针对目前铜钼浮选分离所使用的传统黄铜矿抑制剂存在毒性大、对环境污染严重等问题,开发出新型辉钼矿的抑制剂以实现铜钼的有效分离具有重要的意义。本文拟开发黄腐酸(FA)作为新型高效的辉钼矿抑制剂,通过单矿物浮选试验和人工混合矿浮选试验探究抑制剂浓度、矿浆pH、捕收剂浓度等因素对黄铜矿和辉钼矿可浮性及铜钼分离效果的影响,并采用FTIR和Zeta电位表征手段探究FA在黄铜矿和辉钼矿表面的吸附行为。浮选试验结果表明,FA在pH为4~12的范围内能够有效地抑制辉钼矿的浮选,而对黄铜矿的浮选影响不大;FA能够显著地扩大辉钼矿和黄铜矿之间可浮性的差异。在pH为9,FA浓度为200mg/L,SIBX浓度为20mg/L条件下,人工混合矿试验取得了较好的结果,黄铜矿回收率高达70.20%,辉钼矿回收率仅有16.83%。FTIR和Zeta电位结果表明,FA能够克服静电斥力吸附在辉钼矿表面,并且FA与SIBX在黄铜矿表面存在竞争吸附,SIBX能够取代黄铜矿表面已吸附的FA,使其表面恢复疏水性,而SIBX几乎不影响FA在辉钼矿表面的吸附,使辉钼矿表面保持亲水性,从而能够实现铜钼的有效分离。     

印度洋海盆沉积物中稀土的赋存状态及其浸出研究

印度洋海盆沉积物作为重要的稀土资源，已成为保障我国稀土供应的重要途径。为探究利用印度洋海盆沉积物提取稀土的可行性，通过激光粒度分析、化学物相分析、SEM分析等考察了某印度洋海盆沉积 物中稀土元素赋存状态，并采用硫酸为浸出剂，研究硫酸浓度、液固比、浸出温度及时间对稀土浸出率的影响，对最佳条件下获得的浸出液通过氨水中和沉淀净化。结果表明：①沉积物颗粒极细，体积平均粒径仅 4.47 μm，其主要矿物组成为黏土、锰氧化物、石英、长石、云母、绿泥石和石盐，其中稀土主要赋存于磷灰石中，占总稀土比例达73.10%；②在硫酸浓度2 mol/L，液固比7∶1，浸出温度55 ℃，浸出时间120 min的 最佳条件下，主要稀土元素La、Ce、Nd和Y的浸出率分别为80.57%，66.33%，88.42%和93.25%，高价值的重稀土Gd、Dy和Er浸出率分别为92.63%、55.30%和93.17%。③稀土浸出液成分复杂，且稀土含量偏低，仅有100 mg/L左右，采用氨水调节pH值至5.14，可有效去除Al和Fe，但稀土损失率也达到了30.85%。该研究结果对进一步开发利用深海稀土资源具有重要意义。     

H2O2及海水对铜钼硫化矿浮选分离的影响及机理研究

自然界中黄铜矿与辉钼矿常伴生存在，黄铜矿和辉钼矿的分离常采用浮选方法，而现有的浮选分离法存在环境污染较大等问题。为探究一种清洁、高效的铜钼硫化矿浮选分离方法，在以海水或纯水造浆的情况下，以H₂O₂为氧化剂对黄铜矿和辉钼矿进行预处理，然后进行纯矿物浮选试验和人工混合矿浮选试验，并通过接触角测定和XPS分析来揭示其影响机理。结果表明：①在海水和纯水中，黄铜矿经H₂O₂处理后，可浮性显著降低；在海水中，H₂O₂预处理能提高辉钼矿的可浮性，而在纯水中H2O2的预处理反而会降低辉钼矿的可浮性。②黄铜矿经H₂O₂预处理后可浮性降低，与黄铜矿颗粒表面被H2O2氧化，形成亲水氧化物有关；无论在纯水还是海水中，H₂O₂对辉钼矿可浮性的影响相对较小，主要与H₂O₂对辉钼矿表面的氧化作用较弱有关。③无论在纯水还是海水中，经H₂O₂预处理的黄铜矿与辉钼矿的人工混合矿能较好地实现分离，且在海水中的分离效果更好，这对海水代替纯水进行铜钼浮选分离具有重要的指导意义。     

铜铅分离有机抑制剂FCLS的研究

研究了不同pH值和矿浆电位下有机抑制剂FCLS对黄铜矿和方铅矿的抑制作用。结果表明, 未添加FCLS时, 方铅矿和黄铜矿都具有良好的可浮性。FCLS存在时, 黄铜矿的浮选回收率略有降低, 方铅矿受到强烈的抑制。随着pH值增大, 矿浆电位逐渐降低, 矿浆电位对这两种矿物浮选回收率几乎没有影响。通过红外光谱研究了FCLS与矿物的作用机理, 结果表明, FCLS在方铅矿表面发生了强烈的吸附而在黄铜矿表面发生了微弱的吸附。     

某铜钼矿的可选性研究

矿石中主要金属矿物为黄铜矿、辉钼矿.采用铜钼混选-铜钼混精再磨后铜钼分离的选别工艺流程,得到了含Mo 46.87%、回收率86.24%的钼精矿;含Cu 20.19%、回收率91.64%的铜精矿.     

氧化预处理技术在铜钼硫化矿浮选分离中的研究进展

黄铜矿和辉钼矿是两种典型的硫化矿,其浮选分离一直是业界关注的焦点.硫化矿易氧化,矿物表面氧化程度和氧化产物类型对其浮选行为有重要影响.黄铜矿、辉钼矿在浮选之前进行氧化预处理,它们会产生不同程度的氧化和不同类型的氧化产物,这些原因使矿物的表面原有的性质发生改变,从而改变矿物固有的浮选行为,实现黄铜矿和辉钼矿的浮选分离.论...     

矿浆电位对铜钼浮选分离的影响及机理分析

为探究矿浆电位对铜钼矿浮选的影响，采用黄铜矿、辉钼矿纯矿物作为样品，进行了矿浆pH、浮选药剂种类及用量对矿浆电位影响的研究。结果表明，黄铜矿上浮最佳矿浆电位为360 mV，pH为8。硫化钠、硫酸铵、碳酸钠三种调整剂按质量比1:1:1混合使用时，黄铜矿更易达到上浮电位区间。同时，当矿浆pH为9左右时，巯基乙酸能很好地抑制黄铜矿的上浮，并且对辉钼矿具有很好的选择性作用效果，有利于二者的分离。机理分析结果表明，在矿浆pH为8时，矿浆中生成大量的CuS是促进黄铜矿上浮的主要原因。      

黄铁矿氧化抑制行为及机理研究

利用纯矿物浮选试验研究了次氯酸钠、过硫酸铵及含钙药剂 CK等氧化剂对黄铁矿、黄铜矿可浮性的影响 ,并采用实际矿石进行了验证。根据黄铁矿的电化学性质、接触角测定和黄药在矿物表面的吸附量测定 ,分析了黄铁矿在氧化状态下受抑时的表面性质。结果表明 ,氧化剂能减小黄铁矿的接触角 ,增大亲水性 ,阻止或减少黄药在矿物表面的吸附从而使黄铁矿受到抑制。     

细粒硫化铜矿与易泥化钙镁矿物的浮选分离

承德某硫化铜矿铜品位仅为0.44%,脉石矿物主要为蛇纹石及方解石等钙镁矿物。针对黄铜矿粒度细、脉石矿物易泥化而导致黄铜矿分选效率低的特点,采用"一段脱泥-二段分级分选"的工艺流程,并使用酸化水玻璃作为脉石矿物的主要抑制剂,进行了硫化铜矿选矿试验,取得精矿品位13.97%,回收率82.98%的良好分选指标。通过对矿石的扫描电子显微镜(SEM)分析、单矿物Zeta电位及润湿接触角的测定,表明黄铜矿与蛇纹石及方解石的异相凝聚是其难选的主要原因。酸化水玻璃可以显著降低蛇纹石及方解石的表面动电位,在p H=7~9的浮选区间内使其电位由正变负,消除与黄铜矿的异相凝聚;酸化水玻璃中最具活性的硅酸胶粒可强烈吸附在蛇纹石及方解石表面,增强其亲水性,从而有利于与黄铜矿的浮选分离。     

Selective chalcopyrite flotation from pyrite with glycerine-xanthate as depressant

Micro-flotation tests, adsorption, electrokinetic and FTIR measurements were carried out in order to investigate the selective depression mechanism of sodium glycerine-xanthate (SGX) on pyrite in chalcopyrite flotation. The flotation results showed a large difference in chalcopyrite (>85%) and pyrite (<30%) recovery as stirred pulp-mixing with SGX before the addition of collector sodium butyl xanthate (SBX), at the range of pH 7–10. A much stronger adsorption of SGX on pyrite than chalcopyrite was dramatically revealed by zeta potential measurements, which can explain the better floatability of chalcopyrite than pyrite. The adsorption of SBX onto pyrite was depressed intensely while that onto chalcopyrite was affected slightly when SGX was used as depressant, because of more stronger adsorption between SGX and SBX occurring onto the pyrite surfaces. The absorbed amount of SGX on chalcopyrite increases slightly, over the pH range from 3 to 12, while that on pyrite increases rapidly with the increased SGX concentration, which is consistent with the flotation results. FTIR reflection spectroscopic measurements further demonstrated the depression effect of pre-absorbed SGX on SBX adsorption, which is attributed to its hydrophilic hydroxyl groups.     

The separation of chalcopyrite and chalcocite from pyrite in cleaner flotation after regrinding

In this study, the differences between the separation of chalcopyrite and chalcocite from pyrite in cleaner flotation after regrinding were investigated. In the rougher flotation prior to regrinding, high chalcopyrite and chalcocite recovery were obtained in conjunction with high pyrite flotation recovery due to the activation of pyrite by copper ions during primary grinding. The rougher flotation concentrate was reground in a rod mill before cleaner flotation. It was found that chalcopyrite and chalcocite exhibited different flotation behavior and also affected pyrite flotation differently in cleaner flotation. The mechanism underpinning these phenomena was investigated by a range of techniques including the polarization of mineral electrodes, X-ray photoelectron spectroscopy (XPS) analyses and ethylene diamine tetraacetic acid (EDTA) extraction. It was found that the flotation behavior of both copper minerals and their effect on pyrite flotation after regrinding were governed by their electrochemical activities and galvanic coupling with pyrite.     

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.     

Depressing effect of flocculants on molybdenite flotation

The quality of recycled process water is an important issue in the flotation of Cu–Mo ores. Processing of Cu–Mo ores includes two steps: a bulk flotation where molybdenite is recovered together with Cu sulfides, and a subsequent selective flotation step where molybdenite is separated from depressed copper sulfides. Flocculants are usually employed in the middling thickeners in the copper plant, and in the Cu–Mo bulk concentrate ahead of the molybdenite plant. However, the floatability of molybdenite, similarly to other naturally hydrophobic minerals, is highly sensitive to the presence of both natural and synthetic polymers. In this work flotation tests demonstrate that conventional flocculants, high-molecular weight anionic polyacrylamides (PAM), are strong molybdenite depressants. Low-molecular weight shear degraded polyacrylamides in spite of losing flocculation efficiency maintain depressing ability for molybdenite. Also a non-ionic flocculant, polyethylene oxide (PEO), has been studied in this project. Our results indicate that PEO is an efficient flocculant for molybdenite suspensions in a wide pH range. However, similarly to polyacrylamides, the PEO flocculant also depresses molybdenite flotation.     

铜钼浮选分离中黄铜矿抑制剂的研究进展及展望

铜、钼是我国重要的战略资源，二者主要来源于斑岩型铜钼矿。浮选处理该类矿石资源时，通常采用混合浮选-铜钼分离工艺获得铜精矿和钼精矿。然而，由于黄铜矿和辉钼矿可浮性接近，为了较好的将二者有效分离，常需加入一定量抑制剂以调控二者表面湿润性，进而实现高效铜钼分离。因此，抑制剂一直是铜钼分离的核心所在。本文综述了近年来黄铜矿无机抑制剂、有机抑制剂和组合抑制剂三个方面的研究进展，分析并展望了未来铜钼浮选分离的重点研究方向，旨在为实现绿色高效铜钼分离提供技术及理论支撑。     

影响典型铜矿物可浮性的晶体化学基因研究

为实现“基因矿物加工”系统工程建设，探究基因特征与铜矿浮选的关系，以具有代表性的铜矿物黄铜矿、斑铜矿、孔雀石、蓝铜矿和赤铜矿作为研究对象，通过 XPS、溶解性试验、Zeta 电位、接触角等测试分析及 MS 模拟计算等分析总结了含铜矿物的基因特征。通过浮选试验得到了含铜矿物的天然可浮性为：斑铜矿>黄铜矿> 赤铜矿>孔雀石>蓝铜矿；在乙基钠黄药（NaEX）、丁基钠黄药（NaBX）、异戊基黄药（NaIAX）和丁铵黑药体系下的浮选规律为黄铜矿、斑铜矿有较好的可浮性，而孔雀石、蓝铜矿和赤铜矿的可浮性较差，可浮性优异大致规律为：斑铜矿>黄铜矿>蓝铜矿≈孔雀石>赤铜矿；结合基因特征分析得出含铜矿物的天然可浮性规律与断裂面、断裂键密度和断裂键等基因特征有关，而在 NaEX、NaBX、NaIAX 和丁铵黑药体系下铜矿物的可浮性规律与铜矿物的禁带宽度和表面 S 元素含量基因特征有关。     

柠檬酸对锡石浮选行为的影响及其作用机理分析

通过浮选试验考察了柠檬酸对水杨羟肟酸体系中锡石浮选行为的影响,并结合接触角检测、动电位检测和溶液化学计算分析了其作用机理。在7pH9范围内,以200mg/L水杨羟肟酸为捕收剂浮选,锡石回收率达到80%以上。在pH4时,柠檬酸会对锡石产生明显的抑制作用;柠檬酸用量50mg/L、pH=7条件下,锡石回收率仅为25.3%。锡石表面接触角为33°,加入水杨羟肟酸后锡石接触角升高至120°,柠檬酸的作用又使接触角下降至44°。动电位检测和溶液化学计算表明水杨羟肟酸和柠檬酸均可以化学吸附在锡石表面。柠檬酸一方面增强了锡石表面的亲水性,另一方面减少了水杨羟肟酸在锡石表面的吸附,这两方面的作用使锡石在浮选过程中受到抑制。