矿石粒度对活性炭催化低品位原生硫化铜矿石细菌氧化的影响

通过摇瓶试验,研究了矿石粒度对活性炭催化原生硫化铜矿石细菌氧化浸出的影响。结果表明：在活性炭催化低品位原生硫化铜矿石细菌浸出过程中,矿石粒度对铜的浸出率有较大影响。矿石粒度小于0．1mm最有利于铜的浸出,浸出240h,铜浸出率达83％;矿石粒度过细,溶液中三价铁含量升高,产生的铁沉淀物会直接影响铜的浸出。     

低品位铜矿石的浸出

低品位铜矿石中的铜过去是采用浸出－渗碳法获得的,近年来,一般是采用浸出－溶剂萃取－电积法获得的。在这种新工艺中,浸出工序是将矿石中的铜以铜（Ⅱ）离子的形式溶于硫酸浸出液中,除铜以外,也溶解了铁离子等成分,因此,在下一工序中就要把铜（Ⅱ）离子选择性地萃取到有机相中,再用反萃得到浓的硫酸酸性铜（Ⅱ）溶液。最后,通过电解还原该溶液中的铜（Ⅱ）离子,从而得到金属铜（电解铜）。为了更有效地进行低品位铜矿石的浸出,提出使用各种浸出促进剂,其中包括银离子、界面活性剂、活性碳、铁粉、赤铁矿粉以及铁离子,但是都还…     

矿石粒度和矿浆浓度对原生硫化铜矿细菌浸出的影响

通过摇瓶试验研究矿石粒度和矿浆浓度对原生硫化铜矿石中细菌浸出的影响,并初步探讨了浸矿过程中细菌的氧化活性及其对浸矿的影响。研究结果表明:在原生硫化铜矿石细菌浸出过程中,有利于铜浸出的矿石粒度和矿浆浓度分别是5 mm和20%~25%;溶液中三价铁含量过高或产生的铁沉淀都会直接影响细菌的氧化活性和浸矿效果。     

含砷低品位硫化铜矿生物堆浸工业试验

福建紫金山含砷低品位硫化铜矿年产300tCu和1000tCu生物堆浸工业试验结果表明:铜浸出率随着矿石粒度的减小而提高,矿石粒度为-30mm,浸出周期为270d,铜的浸出率达到80.58%;铜萃取率和电积电流效率随着浸出液pH值的降低和电积液中铁的质量浓度的增加而降低,当浸出液pH值下降到1.19时,铜萃取率下降到了50%;通过增加堆高、定期中和萃余液、增加负载有机相洗涤和活性炭+沙滤+气浮塔脱除电积原液中有机物等工艺改进后,降低了萃取剂、煤油和电能的消耗量,提高了铜的浸出速率,浸出周期为200d,铜浸出率为81.31%,铜萃取--电积的耗电量为2679.98kW.h.t-1,高纯阴极铜生产成本1.05万元.t-1.     

非离子型表面活性剂对风化壳淋积型稀土矿浸出过程的影响

为了缓解风化壳淋积型稀土矿浸取过程存在的浸取周期长、浸出剂用量大和稀土拖尾等问题,以非离子型表面活性剂为助浸剂,氯化镁为浸出剂,对稀土浸出过程进行研究,研究复配浸出剂溶液性质,分析浸矿前后矿物粒径分布,探讨表面活性剂的促渗机理。研究结果显示,加入表面活性剂后,稀土浸出率提高,渗透速度加快,溶液的表面张力和接触角均减小,黏度增大,矿物颗粒的中值粒径明显减小,矿物表面Zeta电位增大,其中加入吐温40后稀土浸出率提高至86.38%,表面张力减小19.00%,接触角减小53.19%,溶液黏度减小4.29%,溶液性质变化最大。加入表面活性剂后可使溶液更容易润湿矿物,进入孔隙的阻力变小,扩散层厚度减小,黏土矿物的膨胀受到抑制,使得溶液浸出稀土的效果更好,其中吐温40对溶液浸出稀土的渗流效果影响最大,助渗效果最好。     

低品位次生硫化铜矿酸性矿坑水喷淋堆浸工业试验

以酸性矿坑水为浸出剂,对紫金山低品位次生硫化铜矿进行堆浸工业试验。重点考察了矿石性质、喷淋制度、堆浸过程中浸矿细菌的种群结构等对矿石铜和铁浸出率的影响。结果表明,矿石堆浸210天,平均铜浸出率65.9%、铁浸出率5.4%。含酸性坑水喷淋次生硫化铜矿生物堆浸的湿法提铜工艺在工业上是可行的。     

永平铜矿氧化矿溶浸试验研究

根据永平铜矿氧化矿的矿物性质和矿物工艺学特征，在实验室进行了氧化矿浸铜试验研究，主要研究了浸出液的酸浓度、铁离子浓度、矿石粒度、浸出时间等因素对铜浸出率的影响，得出了一些有工业实用价值的结论。     

活性炭在原生硫化铜矿细菌浸出中对铜与铁离子吸附的影响

通过摇瓶实验,研究了活性炭在原生硫化铜矿细菌浸出中对铜与铁离子吸附的影响.研究结果表明,活性炭浓度和pH值对活性炭吸附铜和铁离子有重要影响,活性炭对铜和铁离子的吸附量随活性炭浓度增加而增加.在原生硫化铜矿石细菌浸出的初始阶段,添加活性炭可以大大加快铜的浸出速度和提高铜的浸出率,在600h内,铜的浸出率可以达到79%,比不添加活性炭时提高了68%.     

从低品位钼铅矿中提取钼的试验研究

研究了从氧化钼矿石中回收钼,考察了NaOH质量浓度、温度、时间、液固体积质量比对钼浸出率的影响。试验结果表明:在NaOH质量浓度80g/L、温度95℃、液固体积质量比3∶1条件下浸出矿石120min,钼浸出率达80%以上;浸出液先以Na2S溶液沉铅,再以HCl溶液调节pH=8除硅,然后再用HCl溶液调节pH=2.5,用D314大孔弱碱性阴离子交换树脂吸附钼,用10%NaOH溶液在40℃下解吸钼,钼吸附率及解吸率分别达到95%和97%。     

刚果(金)氧化铜矿硫酸浸出的研究

研究了刚果(金)Shamitunba氧化铜矿的浸出过程。详细考察了矿石粒度、初始酸浓度、浸出温度、浸出时间、还原剂加入量及其它因素对铜和钴浸出率的影响。考察了浸出矿浆沉降、过滤和洗涤的效果。试验结果表明,在最佳试验条件下,铜、钴的浸出率分别为95.32%,41.99%。浸出液含铜4.47g/L,浸出液含钴0.032g/L。     

浸出-电沉积法从多金属低品位矿制备铜粉的研究

文章采用浸出-电沉积方法研究了多金属低品位氧化矿提取金属铜的工艺。探讨了工艺中温度、浸出时间、液固比（L／S）、硫酸浓度、矿样粒度、氧化剂等对铜的浸出率的影响。在硫酸浓度为10％,浸出时间控制在5h,液固比取5：1,浸出温度为95℃,粒度0．125mm以下占40％的最优条件下,得到铜的浸出率为82．2％。采用控制阴极电势电积法直接处理硫酸浸出液,在控制阴极电位小于500mV,铜离子的浓度为1～2g／L,H2S04为180g／L的条件下,得到铜含量在99％以上的优质海绵铜。     

表面活性剂对磷钾伴生矿提钾过程的影响

在HCl-H3PO4混酸处理磷钾伴生矿提钾过程中,考察不同类型的表面活性剂对钾浸出率的影响。结果表明,阴离子表面活性剂(十二烷基磺酸钠和十二烷基硫酸钠)的加入能将钾的浸出率提高10~15个百分点,最高可达95.01%。阳离子表面活性剂(十二烷基三甲基氯化铵)以及非离子表面活性剂(聚乙二醇-6000及聚乙二醇-10000)的加入对钾的浸出产生抑制效果。     

含铜金矿石氨氰体系浸金机理研究

对于金以非包裹形式存在的含铜金矿石,直接氰化虽然能取得较高的金浸出率(92%),但氰耗高(130 kg/t),而且氰化物耗量并不与铜的浸出量成线性关系。氨氰体系浸金可以得到较高金浸出率的同时,降低氰化物耗量。该体系中最佳氨氰比为3∶1,最大的氰化钠用量为14.7 kg/t,继续增大氰化钠用量,金的浸出率并不明显增高,而过量的氨则会导致试样中铜的快速溶解,同样不利于金的浸出。试样中的可溶性铜使浸出液中的Cu2+浓度满足氨氰体系浸金的要求,过量的Cu2+对浸金不利。研究结果表明,氨氰体系浸出金的机理可能是铜氨络离子充当氧化剂,而氰铜络离子(以Cu(CN)32-为主)充当浸金剂,浸出液中铜浓度和金浓度变化的四个阶段支持了此浸金机理。     

EFFECT OF CERTAIN SURFACTANTS ON THE LEACHING AND PRECIPITATION PROCESSES IN ZINC FERRITE RESIDUE TREATMENT

The effect of a surfactant mixture of nonylphenolpolyethylene glycol (D1), dinaphthylmethane-4,4′-disulphonic acid (D2), and polyethylene glycol with molecular weight 400 (D3) on the dissolution of zinc and metal impurities present in zinc ferrite residue in dilute sulfuric acid (160 g L^?1 H₂SO₄) as well as on both jarosite and goethite precipitation was studied at 90°C. The following influences of the surfactant mixture (D1 + D2 + D3), determined by comparing the results obtained in the presence and absence of surfactants, were found. Adsorption of surfactants on zinc ferrite residue surface decreases the dissolution of zinc and metal impurities (Fe, Cu, Cd, As, Sb, and Co). Their extraction efficiencies at the end of the super hot leaching process carried out with surfactants are 4.85–6.29% lower than without them. The formation of a sulfur “sponge” layer on the surface of liquor during the dissolution of ZnS present in zinc ferrite residue is hindered by the surfactants due to their effect as wetting agents and sulfur dispersants. The presence of surfactants reduces the amount of zinc and metal impurities (Fe, Cu, Cd, and As) remaining in the solution after jarosite or goethite precipitation by 5.33–5.86% or 8.03–9.93%, respectively. The volume of jarosite and goethite precipitates increases in the presence of surfactants due to their effect as wetting and flocculation agents. On the other hand, D1 and D3 act as complexing agents. The abovementioned effects of surfactants improve the sorption capacity of both jarosite and goethite, thus ensuring better purification of zinc sulphate solutions, but hindering zinc leaching.     

镉车间铜渣中有价金属铜的回收

试验表明 ,在pH <1的硫酸溶液中加入经自然风干后的铜渣和FeSO4 进行堆浸 ,经过 34天二个阶段的自然堆浸作业 ,铜渣中Cu的浸出率可达到 90 %以上 ,该工艺在技术上是可行的     

铁离子对土状铜矿中铜浸出影响研究

考察Fe3+浓度、Fe3+/Fe2+对土状铜矿中铜浸出率的影响,分析了酸浸过程中铁离子提高铜浸出率的机理。结果表明,在矿浆浓度30%、酸浓度36.8g/L、12.0g/L硫酸铁溶液浸出土状矿48h后,铜浸出率为62.4%,与无铁时铜浸出率相比提高了10个百分点。其中有92.6%游离氧化铜、70.3%结合氧化铜、35.6%次生硫化铜和11.8%原生硫化铜被浸出,除原生硫化铜外,均比无铁时有明显提高。并且随着Fe2+/Fe3+的降低,铜浸出率逐渐增加。增加Fe3+浓度提高了溶液电位,从而提高铜浸出率。     

硫代硫酸盐提金理论研究：阴极过程及浸金机理

本文研究了金在硫代硫酸盐溶液中溶解的阴极机理,结果表明,在含铜氨的溶液中,二价铜氨络离子在金表面直接还原,生成的一价铜氨络离子进入溶液后,迅速被氧化再生为二价铜氨络离子,后者又到金粒表面上还原。根据硫代硫酸盐浸金阳、阴极过程电化学研究的结果,提出了氨性硫代硫酸盐浸金的电化学—催化机理及模型。从本质上揭露了铜、氨在硫代硫酸盐浸金过程中的作用,填补了硫代硫酸盐提金理论的空白。     

Investigation of Leaching Kinetics of Copper from Malachite Ore in Ammonium Nitrate Solutions

The production of metallic copper from low-grade copper ores is generally carried out by hydrometallurgical methods. Leaching is the first prerequisite of any hydrometallurgical process. Solutions containing ammonia may allow for selective leaching of the copper from the ore. In this study, the leaching kinetics of malachite, which is an oxidized copper ore, in ammonium nitrate solutions was examined. The effects of some experimental parameters on the leaching process were investigated, and a kinetic model to represent the effects of these parameters on the leaching rate was developed. It was determined that the leaching rate increased with increasing solution concentration, temperature, and agitation speed, as well as decreasing particle size. It was found that the leaching reaction followed the mixed kinetic controlled model, which includes two different leaching processes including the surface chemical reaction (303?K to 323?K [30?°C to 50?°C]) and diffusion through a porous product layer (323?K to 343?K [50?°C to 70?°C]). The activation energies of these sequential steps were determined to be 95.10 and 29.50?kJ/mol, respectively.     

Effects of Surfactant Addition on Dewatering of Alum Sludges

In Taiwan, surfactants are frequently used in the flotation process to aid in solid/liquid separation. Their effect on the dewatering of alum sludge was investigated. Various amounts of cationic and anionic surfactants were added to sludge samples, and the dewatering characteristics of the sludge and the water content of sludge cakes were evaluated. Both surfactants improved the dewatering of the sludge by lowering the specific resistance to filtration, decreasing the bound water content, and increasing the dewatering rate of the sludge. Different combinations of anionic and cationic surfactants and polyelectrolytes were also experimented on to study the effect of surfactant addition on the dewatering characteristics of polyelectrolyte-conditioned sludge. Experimental results indicated that both cationic and anionic surfactants adversely affected the dewatering of the conditioned sludge. The addition of surfactant to the oppositely charged polyelectrolyte proved to be most detrimental to sludge dewatering due to the precipitation between surfactant and polyelectrolyte. The addition of cationic surfactant to the cationic polyelectrolyte-conditioned sludge had the least effect.