黄铁矿高效培养嗜酸氧化亚铁硫杆菌及过程分析

以黄铁矿为能量来源对嗜酸氧化亚铁硫杆菌的高效培养进行了研究,并针对培养过程中黄铁矿的能量利用进行了分析。研究表明,在黄铁矿浓度10 g/L、接菌浓度15%和pH＝2.0的条件下培养144 h后,嗜酸氧化亚铁硫杆菌细菌浓度达到6.4×10⁸个/mL。在培养嗜酸氧化亚铁硫杆菌过程中单位质量黄铁矿提供的能量约为培养基中单位质量FeSO₄·7H₂O提供能量的34.7倍,通过黄铁矿可以实现对嗜酸氧化亚铁硫杆菌的高效培养。     

耐冷嗜酸硫杆菌的生长特性和固定化培养

为解决氧化亚铁硫杆菌、嗜铁钩端螺旋菌等中温菌在低温和高酸的吸附尾液中作氧化剂时生长繁殖慢、氧化Fe²⁺速率低等问题,以耐冷嗜酸硫杆菌为研究对象,结合新疆某地浸采铀现场生产实际,对该菌的生长特性、耐酸驯化和固定化培养进行了探索。结果表明,该菌的接种量以10%为宜;当初始Fe²⁺浓度为0.3~0.5 g/L时,细菌仍能较快氧化Fe²⁺;在5~25℃条件下,耐冷嗜酸硫杆菌氧化Fe²⁺的速率均高于氧化亚铁硫杆菌,即耐冷嗜酸硫杆菌更适于溶浸液低温环境;耐冷嗜酸硫杆菌耐酸驯化后能在pH=0.31的培养液中保持较好的氧化活性;从生物陶粒表面电镜图片中可以观察出较厚的生物膜,固定化细菌和游离态细菌协同氧化Fe²⁺的速率是游离态细菌单独氧化的3.4倍。     

氧化亚铁硫杆菌在硫化矿物表面的吸附

研究了氧化亚铁硫杆菌在黄铁矿、黄铜矿、方铅矿和闪锌矿表面的吸附情况,结果表明,氧化亚铁硫杆菌在4种硫化矿物表面的吸附无明显选择性;溶液初始pH值对氧化亚铁硫杆菌在4种硫化矿物表面的吸附几乎无影响,但酸性环境有利于吸附的发生;细胞悬浮液浓度为0.1～1.0 g/L、矿浆浓度为15 g/L以上和温度为20～30 ℃是氧化亚铁硫杆菌在4种硫化矿物表面吸附的较适宜条件。扫描电子显微镜检测结果显示,氧化亚铁硫杆菌细胞表面的荚膜是重要的吸附位。红外光谱分析结果表明,氧化亚铁硫杆菌细胞表面含有-OH、-NH₂、C=O、C-O等活性基团,它们在吸附过程中起重要作用。     

非金属矿物的微生物加工技术研究(Ⅱ)--黄铁矿的微生物浮选研究

本文介绍了作者采用氧化亚铁硫杆菌(T.f菌)对纯黄铁矿矿物进行微生物浮选的研究成果。研究结果表明 ,T.f.菌能在10min内迅速地吸附到黄铁矿表面 ,使黄铁矿表面由疏水变为亲水 ,丧失可浮性 ,因而T.f.菌是黄铁矿的一种有效的微生物抑制剂。并且指出 ,T.f.菌对黄铁矿的抑制是一种生物胶体的吸附作用。     

非金属矿物的微生物加工技术研究(Ⅰ)--氧化亚铁硫杆菌及其生长规律研究

本文介绍了矿物的微生物加工技术的发展概况,矿物加工中常用微生物——氧化亚铁硫杆菌（Ｔｈｉｏｂａｃｉｌｌｕｓ ｆｅｒ－ｒｏｏｘｉｄａｎｓ,简称Ｔ．ｆ．菌）的结构、生理特性以及采集、培养方法,氧化亚铁硫杆菌分别在９Ｋ培养基和黄铁矿培养基中培养时的生长规律。     

氧化亚铁硫杆菌的分离纯化和生长特性研究

采用平板分离技术分离、纯化得到氧化亚铁硫杆菌,并对其中5株菌株开展生长特性研究。结果表明:2∶2固体培养基是一种较好的能用于分离、纯化氧化亚铁硫杆菌的培养基;氧化亚铁硫杆菌在培养基的初始pH为2.0～2.5时生长速度最快,最佳生长温度为30℃,初始ρ(Fe2+)为4.623g/L,适宜的接种量为10%。各菌株的生长特性存在一定差异。     

喷淋塔中固定化Acidithiobacillus ferrooxidans对Fe2 的生物氧化特性研究

为了增大嗜酸氧化亚铁硫杆菌细胞密度以提高其对Fe~(2+)的氧化速率,利用泰勒花环填料为载体,在喷淋塔中固定嗜酸氧化亚铁硫杆菌,考察固定化细胞对Fe~(2+)的生物氧化性能。采用扫描电子显微镜对载体表面进行形貌表征,X射线衍射仪和傅里叶红外光谱仪对填料表面沉淀进行成分分析。结果表明:在改良的9 K培养基中,嗜酸氧化亚铁硫杆菌被成功的固定在泰勒花环填料上,并伴有少量黄铵铁矾沉淀,这些沉淀和菌体细胞一起构成了生物反应系统的生物膜。嗜酸氧化亚铁硫杆菌在喷淋塔中完成固定化后,溶液初始pH值和温度是影响氧化速率的主要原因,其优化结果分别为2.25和34℃。在此条件下,整个生物反应系统能长期保持稳定的氧化特性,Fe~(2+)的氧化速率为4.27 g/L/h。     

表面活性剂OPD对生物浸出铁闪锌矿的影响

Lan Zhouyue等人在2009年22卷（1）期《Minerals Engineering》上撰文,介绍了表面活性剂对生物浸出铁闪锌矿影响的研究结果。表面活性剂为邻-苯二胺（OPD）,所用细菌为嗜酸氧化亚铁硫杆菌、嗜酸氧化硫硫杆菌和氧化亚铁钩端螺旋菌的混合菌。生物浸出在摇瓶中进行。     

脱硫菌培养条件及脱硫研究

介绍了pH值、培养时间和接种量对氧化亚铁硫杆菌生长的影响。测定该菌对煤炭脱硫效果的结果表明，在9K培养基初始pH=2、接种量15%的情况下，氧化亚铁硫杆菌生长5 d后浓度达108个/mL，10 d后黄铁矿脱除率达到52.29%,全硫脱除率达到37.75%。     

非金属矿物的微生物加工技术研究（Ⅰ）：氧化亚铁硫杆菌？…

本文介绍了矿物的微生物加工技术的发展概况，矿物加工常用微生物－氧化亚铁硫杆菌（Ｔｈｉｏｂａｃｍｌｕｓ ｆｅｒｒｏｏｘｉｄａｎｓ，简称Ｔ．ｆ．菌）的结构、生理特性以及采集、培养方法，氧化亚铁直菌分别在９Ｋ培养基和黄铁矿培养基中培养时的生长规律。     

氧化亚铁硫杆菌的筛选及其特性研究

从广东云浮一硫铁矿的酸性废水中分离出一株氧化亚铁硫杆菌,对其菌落形态和细胞形态进行了初步的探讨,研究了温度、初始pH、Fe2+初始浓度、接种量对细菌氧化Fe2+的影响。试验结果表明,该菌在pH=2 0、温度30～35℃活性最强,同时加大接种量也可以缩短细菌的迟缓期,培养基中过高的Fe2+浓度对该菌生长起抑制作用。     

Bioleaching of a Spanish complex sulphide ore bulk concentrate

In the present work the applicability of bioleaching using a mixed culture of mesophilic microorganisms (Thiobacillus ferrooxidans, Thiobacillus thiooxidans and Leptospirilum ferrooxidans) on a bulk concentrate of a Spanish complex sulphide ore was studied. The bulk concentrate mainly consisted of by chalcopyrite, sphalerite and pyrite. Effects of nutrient medium, stirring, pulp density, temperature and the addition of CO₂ (1% v/v) to the air flow were also studied. The highest leaching rates and recoveries were obtained with mechanically stirred reactors at 5% pulp density and 9K medium. However, by using 9K medium higher jarosite precipitation was observed. Results showed that the optimum temperature for copper bioleaching was 30°C, whereas zinc dissolution increased with a rise in the temperature.     

Influence of the attachment of acidophilic bacteria during the oxidation of mineral sulfides

Acidophilic bacteria found in mining environments are capable of oxidising insoluble sulfide minerals. The use of these bacteria during the oxidation of various mineral sulfides has received significant commercial interest.The attachment of Thiobacillus ferrooxidans and moderately thermophilic bacteria to sulfide minerals was investigated to further understand the mechanism(s) involved in the leaching of sulfide minerals. T.ferrooxidans (DSM 583 and ATCC 23270) and four strains of moderate thermophilic bacteria, Sulfobacillus thermosulfidooxidans, (strain TH1) and Sb.acidophilus (strains THWX, ALV and YTFI) all grown on ferrous iron, sulfur and a chalcopyrite concentrate (termed chalconc) were investigated using 3 sulfide mineral systems; pyrite, a chalcopyrite concentrate (chalconc) and an arsenic containing concentrate (termed arsenoconc). The degree of attachment of all substrate-grown cells along with contact angle measurements of both minerals and cells were determined in order to evaluate the effect of the growth substrate and the hydrophobic interactions on the attachment process. The attachment of both the mesophiles and moderate thermophiles were found to be dependant on the type of growth substrate, the substrate concentration and also the type of mineral studied. Whilst sufur-grown T. ferrooxidans (DSM 583) cells exhibited a higher degree of hydrophobicity, both ferrous iron and chalconc-grown cells showed a greater degree of attachment. This suggests that hydrophobic interactions are not principally responsible for the attachment of T. ferrooxidans to mineral sutfides. However, each moderately thermophilic strain exhibited greater attachment to the mineral sulfides when cultured on either the chalconc sample or elemental sulfur and all showed greater adhesion to the pyrite and arsenoconc samples than to the chalconc sample. Separate shake flask leaching of the sulfide samples T. ferrooxidans and Sb. thermosulfidooxidans (TH1) respectively in conjunction with the results of the attachment studies suggested that the leaching of mineral sulfides was a combination of both the direct and indirect mechanisms.     

The cell attachment and oxygen consumption of two strains of Thiobacillus ferrooxidans

Thiobacillus ferrooxidans is a chemolithoautotropic aerobic bacteria which derives energy for its metabolic functions through the oxidation of ferrous iron, sulfur and insoluble sulfides minerals.The attachment of Thiobacillus ferrooxidans cells to sulfide mineral surfaces was investigated to further understand the mechanism involved in the leaching of sulfide minerals. Two strains of Thiobacillus ferrooxidans (DSM 583 and ATCC 23270) grown on ferrous iron, sulfur and a chalcopyrite concentrate were investigated on three sulfide mineral surfaces; pyrite, chalcopyrite and arsenopyrite. The degree of attachment of all substrate grown cells along with contact angle measurements of both minerals and cells were determined to evaluate the effect of growth substrate and hydrophobic interactions on the attachment process. In addition, concentrations of both ferrous iron and the flotation collector potassium amyl xanthate were also studied. Whilst sulfur grown cells exhibited a higher degree of hydrophobicity, both ferrous iron and chalcopyrite grown cells showed a greater degree of attachment. This suggests hydrophobic interactions at the mineral/cell interface are not principally responsible for the attachment process. Differences in the adhesion of the two strains were also observed and suggests alternative interaction(s) between the cell and mineral surface is/are principally responsible for attachment. Increasing the concentration of ferrous iron as a growth substrate resulted in an increase in the degree of cell attachment. Correspondingly, increasing the concenrration of amyl xanthate decreased the adhesion of Thiobacillus ferrooxidans.Growth substrate, solution pH, ferrous iron, copper and cobalt ion concentrations were also investigated with respect to the oxygen consumption of the two strains of Thiobacillus ferrooxidans. Enzyme reaction kinetics were also studied allowing for determination of Km values for ferrous iron similar to those previously reported. Whilst cells grown on ferrous iron were able to oxidise the iron substrate over the range 1–200mM, cells grown on 1% sulfur were unable to oxidise similar concentrations of the iron substrate. However, following a single subculture onto ferrous iron, sulfur grown cells were able to utilise the ferrous iron substrate all be it at a decreased rate. Investigation of solution pH suggested both cultures had different optimum pH values for ferrous iron oxidation. Increasing concentrations of copper and cobalt (1–100mM) proved to decrease the rate of iron oxidation.     

氧化亚铁硫杆菌培养条件的优化

氧化亚铁硫杆菌生长代谢影响因素有很多,本试验主要对温度、pH、培养基的量以及接种量进行研究,同时也研究了不同氮源及能源条件对菌生长的影响,确定出氧化亚铁硫杆菌的最佳培养条件为温度28℃,pH=2.0,装液量为100mL(250mL锥形瓶),接种量为10%,最容易利用的能源物质是FeSO4,氮源是硫酸铵。     

氧化亚铁硫杆菌筛选及基质中Fe2+氧化研究

用液体、固体培养基交替培养的方法从某矿酸性矿坑水中得到一株氧化亚铁硫杆菌,研究了不同初始Fe2 浓度对该菌氧化速率的影响,同时还研究了初始pH值与初始Fe2 浓度对培养过程中沉淀产生的影响。结果表明:初始Fe2 的浓度为9.05 g/L,pH值为2.0左右是减少沉淀产生和发挥细菌氧化活性的最佳条件。     

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.     

捕收剂烯丙基异丁基硫氨酯在硫化铜矿表面的吸附机理

烯丙基异丁基硫氨酯(ATC)是新一代酯类选矿药剂,它对黄铜矿捕收力强,黄铁矿捕收力弱,是铜硫分离的优良捕收剂。为了考察ATC对黄铜矿和黄铁矿分离的影响及吸附机理,在纯矿物浮选试验的基础上,进行了动电位、吸附量测量试验和红外光谱分析。结果表明,ATC在试验pH范围内对黄铜矿的捕收能力强于对黄铁矿的捕收能力;ATC的捕收力及选择性均强于传统捕收剂Z-200;在pH=9.0、ATC用量为11.8 mg/L时,黄铜矿与黄铁矿回收率相差55个百分点;矿浆pH对黄铜矿可浮性影响较小,对黄铁矿可浮性影响大;ATC用量对黄铜矿电位影响大,对黄铁矿电位影响小;红外光谱分析表明ATC在黄铜矿表面是化学吸附,在黄铁矿表面是物理吸附。