MPEC技术对黑曲霉浸出铜尾砂的影响

应用MPEC技术调控黑曲霉菌丝形态,以实现铜尾砂的高效浸出。研究了Ti SiO4微粒子浓度对黑曲霉菌丝球直径影响,及其发酵液浸出铜尾砂效果。结果表明,添加Ti SiO4微粒子对黑曲霉菌丝球直径及其发酵液浸出铜尾砂有显著影响,当Ti SiO4微粒子浓度为25 g/L时,菌丝球直径为0.65 mm,铜浸出率可达84.5%。     

MPEC技术对黑曲霉浸出铜尾砂的影响

应用MPEC技术调控黑曲霉菌丝形态,以实现铜尾砂的高效浸出。研究了Ti SiO4微粒子浓度对黑曲霉菌丝球直径影响,及其发酵液浸出铜尾砂效果。结果表明,添加Ti SiO4微粒子对黑曲霉菌丝球直径及其发酵液浸出铜尾砂有显著影响,当Ti SiO4微粒子浓度为25 g/L时,菌丝球直径为0.65 mm,铜浸出率可达84.5%。     

菌丝球形态的黑曲霉发酵液浸出铜尾砂

尾砂中含有大量的金属,是一种潜在的可利用资源。旨在研发一种从铜尾砂中回收铜的生物浸出方法。利用正交设计,通过摇瓶试验,研究培养温度、发酵时间、接种量及培养基成分对黑曲霉菌丝球形态的影响,进而研究不同菌丝球形态的黑曲霉发酵液对尾砂中铜的浸出。研究表明,铜的浸出率随着黑曲霉菌丝球直径的减小而升高。在温度30℃,接种量0.8%(OD₆₀₀=0.1),马铃薯-蔗糖含量30%,发酵时间65 h的优化发酵条件下,获得大量表面光滑、直径为0.96 mm的菌丝球;利用该条件下的发酵液,在30℃,180 r·min^-1条件下浸出3 d,铜的浸出率达83.25%。     

铜砷滤饼废渣的生物浸出

采用生物浸出法处理铜砷滤饼废渣,考察了pH值、温度和菌种对浸出效果的影响,分析了铁氧化菌浸出机理和将生物浸出用于含砷废渣无害化处理的可行性. 结果表明,微生物对铜砷滤饼浸出起促进作用,热酸预处理后在50℃、pH值为1.5的条件下,以中度嗜热西伯利亚硫杆菌(Sulfobacillus sibiricu)浸出7 d,砷浸出率达91.33%,铜浸出率达94.22%.     

硫铁矿尾矿中铜的硫酸浸出

采用酸浸法提取硫铁矿尾矿中有价元素铜。研究了硫酸质量分数、浸出时间、矿石粒度、矿石投加量、浸出温度和转速对铜浸出的影响。在单因素实验的基础上,采用正交实验法对浸出工艺条件进行优化。采用扫描电镜(SEM)和能谱仪(EDS)对酸浸前后尾矿表面的微观形貌进行了分析,初步探讨了酸浸反应后期抑制Cu浸出的影响机制。结果表明,酸浸铜的最佳工艺条件为：硫酸质量分数30%、浸出时间6 h、矿石粒度150 ?m、矿石用量5 g、浸出温度108℃、转速440 r/min,在此条件下,铜的浸出率为50.68%。扫描电镜和能谱分析表明,浸出残渣表面被微米级的二氧化硅颗粒紧密包裹,钝化了后期的浸出反应。     

黑曲霉的产酸优化和对鸡粪的间接生物浸出效果

畜禽粪便是传统有机肥料,但近年来畜禽粪便中重金属含量过高。生物浸出技术可有效去除重金属,且具有低成本、低能耗和少污染的优势。从鸡粪中分离出一株产酸能力强的真菌,经过鉴定为黑曲霉。黑曲霉培养液对鸡粪进行生物浸出。通过正交实验优化黑曲霉产柠檬酸的条件,并考察浸出过程中重金属浸出率和形态的变化。结果表明,最优产酸条件为:蔗糖浓度100 g/L、接种量40 ml/L和温度30℃。在此条件下,柠檬酸的产量71.23 mmol/L。经过20 h生物浸出后,Cu、Zn和As浸出率分别为63.93%,79.22%和42.55%,达到《土壤环境质量农用地土壤污染风险管控标准(试行)(GB 15618—2018)》的标准。间接生物浸出过程对鸡粪重金属形态具有显著改变,大大降低鸡粪中重金属对环境造成的风险。     

黑曲霉的产酸优化和对鸡粪的间接生物浸出效果

畜禽粪便是传统有机肥料,但近年来畜禽粪便中重金属含量过高。生物浸出技术可有效去除重金属,且具有低成本、低能耗和少污染的优势。从鸡粪中分离出一株产酸能力强的真菌,经过鉴定为黑曲霉。黑曲霉培养液对鸡粪进行生物浸出。通过正交实验优化黑曲霉产柠檬酸的条件,并考察浸出过程中重金属浸出率和形态的变化。结果表明,最优产酸条件为:蔗糖浓度100 g/L、接种量40 ml/L和温度30℃。在此条件下,柠檬酸的产量71.23 mmol/L。经过20 h生物浸出后,Cu、Zn和As浸出率分别为63.93%,79.22%和42.55%,达到《土壤环境质量农用地土壤污染风险管控标准(试行)(GB 15618—2018)》的标准。间接生物浸出过程对鸡粪重金属形态具有显著改变,大大降低鸡粪中重金属对环境造成的风险。     

ICP-OES测定铜尾矿中的铜铅锌银

为准确快速地检测铜尾矿中的铜铅锌银,选择电感耦合等离子体原子发射光谱仪(ICP-OES)对其进行测定,对实验条件、方法检出限、精密度和加标回收率做了研究。铜尾矿样品经氢氟酸-盐酸-硝酸分解后,用ICP-OES同时测定铜铅锌银4种元素,方法的检出限为0.000 62～0.003 5μg·m L-1,精密度为0.67%～3.08%,回收率为90.0%～110.0%。     

生物浸出低品位镍铜硫化矿中的镍、铜、钴

报道了硫杆菌在3种不同方式下浸出低品位镍铜硫化矿的实验结果. 采用通气气搅浸出,在15%矿浆浓度下,浸出20 d后,镍、铜、钴浸出率可分别达到95.4%, 48.6%和82.6%;采用通气搅拌浸出,在25%的矿浆浓度下,浸出14 d后,镍、铜、钴浸出率分别为80.2%, 45.2%和78.4%. 采用柱式渗滤浸出,在液固比为40:1情况下,浸出49 d后,镍、铜、钴浸出率分别为48.5%, 37.5%和33.6%.     

黑曲霉菌一步浸取低砷硫化矿:Taguchi正交优化(英文)

A study was carried out to examine the possibility for Aspergillus niger strain KBS4 to bioleach metals from sulphide ore with low concentration of arsenic and to optimize the parameters that affect this process by orthogonal array optimization. Fungal sample was collected, purified and sequenced. The bioleaching process was optimized with L25 Taguchi orthogonal experimental array design. Five factors were investigated and 25 batch bioleaching tests were run at five levels for each factor. The parameters were initial pH, particle size, pulp density, initial inoculums and residence time for bioleaching. The experimental results showed that under optimized leaching conditions: pH 5.5, particle size 180 μm, initial inoculums size 3×10 7 spores per ml, pulp density 15% and residence time of 20 days, the bioleach ability of metals were 63% Fe, 68% Zn, 60% As, 79% Cu and 54% Al. The biosorption of metal ions by fungal biomass might occur during the bioleaching process but it did not hinder the removal of metal ions by bioleaching.     

Bioleaching of copper and other metals from low‐grade oxidized mining ores by Aspergillus niger

A study was initiated to determine the feasibility of using the fungus Aspergillus niger for bioleaching metals from oxide low‐grade ore. Large quantities of the metals are embodied in the low‐grade ores and mining residues that can be recovered. Presently available techniques (pyrometallurgical and hydrometallurgical) are expensive or may have a negative impact on the environment. An oxidized mining ore containing mainly copper (7245 mg kg^?1 residue) was studied. In this study, the fungus A niger produced a variety of organic acids. Addition of small quantities of sulfuric acid enhanced the organic acids, efficiency. Various agricultural wastes were evaluated as substrates and a maximum solubilization of 68% for copper for a medium containing potato peels was achieved. In conclusion, leaching of copper from a mining ore is technically feasible using A niger. Further research must be performed to increase the rate of copper removal. Copyright © 2003 Society of Chemical Industry     

One Step Bioleaching of Sulphide Ore with Low Concentration of Arsenic by Aspergiilus niger and Taguchi Orthogonal Array Optimization

A study was carried out to examine the possibility for Aspergillus niger strain KBS4 to bioleach metals from sulphide ore with low concentration of arsenic and to optimize the parameters that affect this process by orthogonal array optimization. Fungal sample was collected, purified and sequenced. T     

布氏酸菌浸出紫金山铜矿过程特性

研究了布氏酸菌浸出紫金山铜矿过程的特性. 考察了初始pH、接种量和矿浆浓度对浸出率的影响,表明布氏酸菌浸出的最佳操作条件为pH 2.0、接种量10%、矿浆浓度5%. 探讨了布氏酸菌的浸出机理,紫金山铜矿的浸出是细菌直接氧化和Fe3 化学氧化复合作用的结果. 布氏酸菌(65oC)对紫金山铜矿的浸出能力强,是氧化亚铁硫杆菌(31℃)的1.7倍,具有良好的工业应用前景.     

四株黑曲霉对高磷铁矿脱磷的研究

研究了四株不同来源的黑曲霉对高磷铁矿的脱磷作用,结果表明,在NBRIP培养基中,四株黑曲霉都能有效脱除高磷铁矿中的磷,但脱磷效率存在一定的差异,脱磷率从高到低依次为WIT-4>WIT-3>WIT-2>WIT-1。分析了四株黑曲霉对高磷铁矿的脱磷机制,发现黑曲霉生长代谢产生有机酸使体系可滴定酸浓度增加及pH下降是其脱磷的主要原因。     

硫杆菌浸出低品位镍铜硫化矿

阐述了氧化亚铁硫杆菌(TF5)和氧化硫硫杆菌(TT)在摇瓶中浸出金川低品位含钴、镍、铜硫化矿的工艺条件实验. 结果表明,浸出过程的pH值应控制在2.0左右;细菌的接种量应控制在3.0?109个/ml左右;低矿浆浓度有利于浸出的进行;氧化亚铁硫杆菌和氧化硫硫杆菌混合浸出,以2:1的比例混合比1:1的比例浸出率要高.     

铜蓝的细菌氧化浸出

研究了福建紫金山铜矿中主要目的矿物之一铜蓝的细菌浸出过程的影响因素,考察了铜蓝纯矿物的浸出特性. 实验室条件下细菌浸出铜蓝纯矿物的适宜条件为：接种量100%,矿浆浓度<5%,初始Fe2+浓度4.0 g/L. 20 d浸出周期内铜蓝浸出率可达60%以上. 通过向纯矿物浸出体系中添加Fe3+、黄铁矿和H2O2,探讨提高溶液氧化电位以强化浸出效果的可能性. 结果表明,添加Fe3+和H2O2对于提高溶液的氧化性效果不显著,同时影响细菌的浸出. 添加黄铁矿则能有效提高浸出过程的氧化电位,以1:2或1:1质量比添加黄铁矿能明显加快铜蓝的细菌浸出速率.     

Fixed bed and reduced lumped diffusion model parameter estimation of copper biosorption using Aspergillus niger biomass

In this study, fixed bed model and reduced lumped diffusion model were used to explain biosorption behaviour of Cu (II) in a continuous column of Aspergillus niger biomass. The breakthrough time was evaluated for both models as a function of influent flow rate and bed height for a feed solution at 10 mg/L metal ion concentration and compared with experimental results. MATLAB was used to solve the partial differential equations and breakthrough curve was plotted. The breakthrough time obtained experimentally was comparable with data evaluated by these models. It was observed that fixed bed model and reduced lumped diffusion model can predict column dynamics more accurately at high flow rate, that is, at 9.8 mL/min for all (2.1, 3.1, and 4.1 cm) bed heights. © 2011 Canadian Society for Chemical Engineering     

黑曲霉β-葡萄糖苷酶的研究进展

系统介绍了近年来黑曲霉β-葡萄糖苷酶(EC3.2.1.2)的酶解特征、酶学性质、催化机制、活性中心、生物学功能及应用技术等方面的研究进展,并展望了其应用前景。