中温嗜酸硫杆菌浸出低品位硫化铜矿

研究了中温嗜酸硫杆菌的生长条件, 对黄铜矿进行了细菌浸出试验研究。研究表明, 中温嗜酸硫杆菌最适宜的生长条件为: pH值为2, 温度为30±1 ℃, 此条件下细菌浓度为2.24×10⁷个/mL。接种量、矿浆浓度对黄铜矿中铜的浸出率有显著的影响, 随着接种量的增加, 铜的浸出率提高。在相同浸出时间内, 矿浆浓度5%左右时, 黄铜矿中铜的浸出率最高。低品位硫化铜矿柱浸试验结果表明: 细菌浸出75 d, 铜的浸出率为45%。     

较低温度下细菌浸出黄铜矿工艺影响因素研究

以黄铜矿为研究对象，在温度较低的浸出条件下（15℃）采用正交试验的方法考察了矿石粒度、矿浆浓度、酸度、接种量以及起始Fe²⁺浓度对氧化亚铁硫杆菌（T.f菌）摇瓶浸出黄铜矿浸出过程的影响。试验结果表明：初始Fe²⁺浓度对细菌浸铜工艺影响最为显著；在15℃下的最佳浸出工艺条件为初始Fe²⁺浓度为6g/L，酸度控制在pH=2.0，接种量保持在15%，矿浆浓度为15%，矿石粒度为-200目。     

黄铜矿低温下银离子催化细菌浸出

在低温(8～10℃)下研究Ag 催化中等嗜热嗜酸菌氧化亚铁硫杆菌(Thiobacillus Ferrooxidans)浸出黄铜矿的作用,考察主要工艺因素对添加Ag 催化浸出过程的影响.结果表明,Ag 催化细菌浸出作用在低温浸出的初始阶段最为明显,添加Ag 的初始浓度为15mg/L时,90d后铜的最终浸出率达到58.96%,比未添加Ag 时高出近一倍,最佳浸出工艺条件为接种量20%,矿石粒度-74μm,矿浆浓度2%,pH值2.5.     

银山低品位复杂硫化铜矿生物浸出条件优化研究

采用摇瓶摇床浸出预实验与正交实验, 对江西银山低品位复杂硫化铜矿进行了浸出条件试验, 对浸出菌种、温度、pH值、转速和矿浆浓度等条件进行了优化。实验结果表明, 当浸出温度45 ℃, 浸出菌为嗜热氧化硫硫杆菌与嗜酸喜温硫杆菌的组合, 浸出体系pH值为1.7, 转速190 r/min, 矿浆浓度为10%时, 铜离子的浸出率达到72.3%。该研究为江西银山低品位复杂硫化铜矿的微生物冶金技术工业化提供了理论依据。     

永平低品位原生硫化铜矿石细菌浸出条件研究

为回收利用永平铜矿废矿石中的低品位原生硫化铜矿资源，通过摇瓶实验，研究了接种量、初始Fe^2＋浓度、矿浆酸度、矿石粒度和矿浆浓度等条件对永平低品位原生硫化铜矿石细菌浸出的影响。研究结果表明：有利于铜浸出的条件是接种量20％，初始Fe^2＋浓度0g／L，初始pH值1．2，浸出过程控制pH值小于1．50，矿石粒度5mm，矿浆浓度20％～25％；溶液中三价铁含量过高或产生铁的沉淀都会直接影响细菌的浸矿效果；尽管浸矿细菌能很好地适应浸矿环境，但铜的浸出速度偏慢、浸出率偏低，有待于采取强化浸出措施。     

嗜热硫氧化硫化杆菌与喜温嗜酸硫杆菌混合浸出铁闪锌矿研究

采用正交试验, 通过考察温度、pH值、喜温嗜酸硫杆菌接种时间和喜温嗜酸硫杆菌接种浓度4个因素, 研究硫氧化硫化杆菌与喜温嗜酸硫杆菌混合菌对铁闪锌矿浸出的影响。试验结果表明: 氧化硫细菌的加入, 有助于消除铁闪锌矿浸出过程中生成的、覆盖在矿物表面的元素硫, 使得硫氧化硫化杆菌和喜温嗜酸硫杆菌混合菌浸出铁闪锌矿的效果比单一硫氧化硫化杆菌浸出效果好; 混合菌浸出铁闪锌矿时浸出率达到54.2%, 而单一硫氧化硫化杆菌浸出时浸出率为46.8%。正交试验结果统计分析表明混合菌浸出铁闪锌矿的最优条件为: pH=1.8、第3 d接种喜温嗜酸硫杆菌和喜温嗜酸硫杆菌接种浓度2.5×10⁶个/mL; 其中pH值是影响混合菌浸出铁闪锌矿的主要因素, 其次是喜温嗜酸硫杆菌接种浓度及喜温嗜酸硫杆菌接种时间。     

用中等嗜热细菌常规和电化学生物浸出黄铜矿精矿

《Hydrometallurgy》2011年106卷第(1/2)期发表Ali Ahmadi等人文章,介绍用中等嗜热细菌常规和电化学生物浸出黄铜矿精矿的研究结果。在各种矿浆浓度以及在有和无细菌的情况下,进行了从Sarcheshmen黄铜矿精矿中提取铜的常规和电化学生物浸出试验。浸出条件:一台2 L搅拌式电生物反应器,矿浆含固量为0.2 kg/L,初始pH     

吉林铜钴镍多金属硫化矿的生物浸出试验研究

吉林某铜钴镍多金属硫化矿品位低,成分复杂,对其开展了生物摇瓶浸出与柱浸试验研究,结果表明:浸出温度对铜钴镍浸出率的影响显著,生物摇瓶浸出的适宜条件为矿浆浓度15%,初始pH值1.5,浸出温度30℃,不添加Fe~(2+);酸浸预处理7d后进行生物柱浸试验,矿石粒度为-10 mm,接菌浸出60 d后,铜、钴、镍的浸出率分别为7.32%、27.47%和27.08%,与矿石粒度-20 mm无菌浸出的条件相比,钴镍浸出率提高了近8个百分点,说明细粒有菌条件有利于金属的浸出;分析浸矿菌群组成,优势菌主要为嗜酸硫杆菌属(Acidithiobacillus)和钩端螺旋菌属(Leptospirillum)。     

嗜热嗜酸A.b.酸杆菌浸出硫化锌精矿

用分批反应器研究嗜热贝莱尔雷伊 (Brieleyi)酸杆菌 (简称A b 细菌 )浸出闪锌矿的动力学。在温度 65℃ ,pH =2条件下测定了A b 细菌在闪锌矿表面的吸附量 ,以及进行了闪锌矿粒的生物浸出试验。测定了闪锌矿浸出过程中前 30min时A b 细菌在矿物表面和溶液中的分布率 ,分布的平衡常数与朗格缪尔等温线相符。当向含A b 细菌的矿浆中加入 0 3、1 4kg/m3Fe3 时 ,由于形成黄钾铁矾类的铁沉淀物 ,导致浸出率明显下降。为了测定A b 细菌在闪锌矿表面生长动力学和化学计量参数 ,对分批生物浸出模型中不加Fe3 的浸出液采集的浸出数据进行了分析。这些生长参数表明 ,嗜热A b 细菌对闪锌矿的生物浸出率约是普通嗜中温铁氧化硫杆菌的 7倍。用分批浸出模型和估计的参数值模拟闪锌矿的初始粒度、细菌初始总浓度和闪锌矿矿浆的初始浓度三个重要变量对闪锌矿浸出率的影响。     

黄铜矿的嗜热细菌生物浸出工艺研究:温度-pH-氧化还原电位之间的依赖关系

嗜热细菌生物浸出黄铜矿的铜浸出率,取决于温度、pH和氧化还原电位,而且还取决于所使用的嗜热细菌的活性.研究了在不同的pH值和温度并有着不同的初始Fe3+数量的条件下,使用三种嗜热细菌浸出时达到的铜浸出率.获得的结果表明.由于Acidianus brierleyi(缩写为A.brierleyi菌)浸出铁(以Fe3+形式)的能力很低,由接近临界值(450mV,Ag°/AgCl参比电极)的氧化还原电位,反映出达到了很高的生物量浓度,在这样的氧化还原电位下浸出时铜浸出率最高.相比之下,由于Sulfolobus metallicus(S.metallicus菌)和Metallosphaera sedula(缩写为M.sedula菌)较高的浸出铁(以Fe3+形式)的能力,由很高的氧化还原电位反映出的很高的生物量浓度,再结合Fe3+以黄钾铁矾(KFe3[SO4]2·(OH)b)形式的沉淀作用,因而就降低了浸出速率.因此,在对于嗜热细菌的生长是最佳的温度时,并不总是意味着能达到很高的铜浸出率.一般地说,最高的铜浸出率是在初始pH值为1.5的条件下达到的.然而,在初始pH值为2.5时观测到比在pH 2.0时达到了更高的浸出率,证实了在高pH值时黄铜矿的生物浸出是受氧化还原电位而不是由pH或温度所控制的.当提供的为激发浸出反应所需的初始的Fe3+数量不足时,双向酸杆菌的生物浸出能力就会降氏,或浸出反应受到抑制,而硫化裂片菌和金属丝菌对初始的Fe3+提供量就没有那么敏感.这一结果证实了对矿物表面直接的酶促催化作用,能引发黄铜矿的生物浸出反应,但稍后氧化还原电位就控制着黄铜矿的浸出速率.     

Iron solubilization during anaerobic growth of acidophilic microorganisms with a polymetallic sulfide ore

Acidithiobacillus ferrooxidans at 30 °C and Sulfobacillus thermosulfidooxidans at 47 °C were selected from a preliminary screening of various acidophiles for their ferric iron reduction capacities during anaerobic, autotrophic growth on sulfur. The selected cultures were used with a polymetallic sulfide ore under anoxic conditions to demonstrate enhanced solubilization of iron during leaching in shaken flasks and enhanced removal of iron from laboratory ore-leaching columns, compared to leaching with continuous aeration. Ore-associated, ferric iron-rich precipitates, which were formed under previously oxidizing conditions, were a potential influence on extraction of target metals and percolation through ore columns and were available as the source of ferric iron for anaerobic sulfur oxidation. Over twice as much iron was removed by moderate thermophiles when anoxic phases were introduced during the leaching. Enhanced removal of iron and some improvement in extraction of base metals from ore fragments were also demonstrated with a selected “Sulfolobus”-like strain during growth and leaching with alternating periods of aeration and anoxic conditions at 70 °C.     

难选低品位铜镍矿细菌浸出的研究

阐述了难选低品位铜镍矿细菌浸出试验 ;考察了Ag+对该矿细菌浸出的催化作用 ,并初步讨论了其催化机理 ;依据多金属硫化矿细菌浸出机理提出了两段细菌浸出工艺 ,排除了镍对黄铜矿溶解的负面影响 ,使铜、镍浸出率分别达到 68 0 7%和 68 1 3%。     

亚氯酸钠氧化浸出黄铜矿研究

为了实现黄铜矿的高效浸出，研究了酸性条件下亚氯酸钠氧化浸出黄铜矿的适宜工艺条件，并进行了浸出动力学研究和浸出机理分析。结果表明，在亚氯酸钠与黄铜矿的物质的量之比为6、浸出液的pH=4、浸出温度为55 ℃、浸出时间为0.25 h时的铜浸出率为82.36%；亚氯酸钠在酸性条件下高效氧化浸出黄铜矿与亚氯酸钠能分解出氧化活性高的物质ClO₂、ClO^-₃和Cl₂有关；亚氯酸钠氧化浸出黄铜矿的过程由界面化学反应控制，活化能为42.69 kJ/mol。     

云南大红山铜矿化学浸出研究

以云南大红山铜矿的铜精矿为研究对象,分别考查其在稀硫酸、硫酸高铁、硫酸亚铁三种介质中的溶解情况。通过试验研究发现,在pH1.0~2.0、常温常压条件下,该铜精矿基本不溶于稀硫酸溶液和硫酸高铁溶液,而在硫酸亚铁溶液中该铜精矿溶解速率明显加快,但浸出后期有明显的钝化现象。浸渣XRD和SEM分析表明,硫酸亚铁溶液浸出后浸出渣有单体硫物相存在,而且矿物表面有明显的"腐蚀坑",能谱分析也证实矿物表面有硫元素过量的情况。另外,硫酸亚铁溶液浸出过程中体系酸耗明显增加,这一方面是由于Fe2+离子氧化造成的,另一方面矿石的大量溶解也增加了酸耗量。     

Bioleaching of chalcopyrite by Acidithiobacillus ferrooxidans

Acidithiobacillus ferrooxidans (A. ferrooxidans) was selected to experimentally study the effects of bacteria on the oxidation of chalcopyrite. The results indicated that A. ferrooxidans remarkably promoted the oxidation of chalcopyrite. The pH of the cell broth medium was observed to increase and then decrease during the bioleaching experiment. The number of suspended bacteria in the bio-oxidation process could be divided into three stages: the initial 4 days, in which the bacteria attached to the chalcopyrite surface and the number of suspended bacteria slightly decreased; day 5 to day 52, in which the suspended bacteria clearly increased with time and reached a maximum of 3.58 × 10⁷ cells/L on day 52; and day 53 to day 80, in which the number of suspended bacteria decreased. Other parameters such as redox potential (Eh) and iron ion concentrations increased with time. SEM micrographs showed that the cells were directly attached to the erosion pits on the smooth surfaces of the chalcopyrite. The erosion pits were similar to the bacteria in shape and size, and thus, the pits were likely products of dissolution by organic acids secreted by the attached cells. Compared to the unoxidized chalcopyrite, the elemental sulfur of the eroded chalcopyrite was clearly reduced, and the elemental oxygen was slightly increased. Moreover, a biofilm was present on the surfaces of the chalcopyrite particles. Therefore, the adherence of the cells to the mineral surfaces played a predominant role in altering the mineral appearance, which is important during the leaching of chalcopyrite.     

Effects of ultraviolet irradiation on bacteria mutation and bioleaching of low-grade copper tailings

This paper studies the effects of ultraviolet irradiation on the mutation of bacteria (i.e., Acidithiobacillus ferrooxidans LD-1) and on the bioleaching system for low-grade copper tailings. It is shown that ultraviolet irradiation can lead to an obvious LD-1 mutation, can improve bio-activity and bioleaching capability. The mutant LD-1 bacteria, after ultraviolet irradiation for 30 min, had the best oxidation activity, the oxidation rate of ferrous ion (Fe²⁺) in mutant bacteria culturing medium can reach 100% after 24 h (18 h less than that of the original bacteria under the same leaching conditions). After 30 days, copper extraction with mutant bacteria is increased by about 17%, compared with original bacteria, and by 70% compared to chemical leaching. These results show that the effects of mutant bacteria after ultraviolet irradiation are better than those of the original bacteria and much better than those of chemical leaching. The improved bioleaching rate of the mutant bacteria is attributed to the faster propagation rate and capabilities for stronger sulfuric acid generation. This study shows that mutant bacteria from ultraviolet irradiation have great potential for improving copper recovery from low-grade copper tailings.     

铜矿山残留硫化铜矿细菌浸出试验研究

本文阐述了开采完毕的矿坑中硫化铜矿的细菌浸出小型试验及模拟矿层结构的柱浸试验。其结果表明，残留疏化铜矿中铜矿物以黄铜矿为主，粒度为－０．０７４ｍｍ的矿石经７天细菌浸出，铜的浸出率可达２０％，加入一定量Ａｇ￣＋可使铜的浸出率提高至８０％～９０％，同时抑制了铁溶出。在模拟柱浸中，矿石粒度对铜的浸出有很大影响，粒度为２０～１００ｍｍ的矿石经１３４天的细菌浸出，铜浸出率可达到１０％左右。     

低电位化学浸出云南大红山黄铜矿

通常认为Fe3+离子是溶浸黄铜矿的有效氧化剂,Fe2+仅仅是Fe3+离子的供给源。但是有试验研究表明,对某些性质的黄铜矿而言,Fe2+离子比Fe3+离子具有更强的溶浸作用。本文对比了Fe2+与Fe3+离子浸出云南大红山黄铜矿的差异,详细研究了pH值、溶氧和Fe2+离子浓度等因素对低电位化学浸出的影响,并根据试验研究结果,系统总结了低电位化学浸出云南大红山黄铜矿的规律。     

Effects of quartz addition on chalcopyrite bioleaching in shaking flasks

This paper studies the effects of quartz on bioleaching of chalcopyrite by Acidithiobacillus ferrooxidans, LD-1 through shaking flask experiments. The results showed that quartz concentration can affect the copper extraction. After 32 days, copper extraction of the leaching system at 50 g L⁻¹ quartz concentration increased by about 20%, compared with that of the leaching system without quartz. XRD analysis showed that the amounts of jarosite on the chalcopyrite surface may reduce by the mechanical friction action between fine particles of quartz and chalcopyrite. The analysis of SEM indicated that the surfaces of chalcopyrite particles were eroded by different degrees and the degrees of change were the same as the effects of quartz concentration on copper extraction.     

活性炭催化浸出原生硫化铜矿研究进展

文章综述了活性炭催化浸出原生硫化铜矿的机理和近十年的研究进展,指出用活性炭催化原生硫化铜矿的工艺投入工业生产的可行性。