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1.
铁闪锌矿浮选精矿生物浸出   总被引:5,自引:1,他引:4  
石绍渊  方兆珩 《化工学报》2004,55(7):1145-1149
研究了氧化亚铁硫杆菌浸出铁闪锌矿浮选精矿的过程, 考察了正无菌、原菌种与驯化菌等条件下铁闪锌矿的浸出效果和矿浆浓度对矿物中有价金属浸出速率的影响. 摇瓶试验表明: pH值2.0、温度35 ℃、细菌接种量10%、矿浆浓度5%、矿石粒度<35.5μm(90%以上)和摇床转速160r&#8226;min-1浸出条件下, 经过驯化的氧化亚铁硫杆菌能够显著地提高铁闪锌矿的溶解速率和浸出率;提高矿浆浓度导致铁闪锌矿中有价金属浸出率降低, 但单位时间内总的锌离子浸出量相应提高.  相似文献   

2.
耐低pH的氧化亚铁硫杆菌选育及其氧化硫酸亚铁的初步研究   总被引:12,自引:0,他引:12  
低pH条件下高效氧化硫酸亚铁的氧化亚铁硫杆菌的选育是两步法生物浸出工艺应用的前提条件. 本文经定向培育和连续培养筛选得到pH为1.7~2.0条件下氧化硫酸亚铁的氧化亚铁硫杆菌驯化菌,其氧化硫酸亚铁的最适pH值由原来的2.0~3.0下降到1.7~2.0,在初始pH为1.7条件下培养48 h后,9K培养基中Fe2+氧化率从13.1%提高到85%. 动力学研究结果表明,该菌在250 ml摇瓶中装量100 ml、接种量10%、起始pH=1.7、温度31℃、转速120 r/min的优化条件下培养52 h后,9K培养基中Fe2+氧化率在98%以上,对数期的细菌比生长速率为0.0635 h-1,与出发菌株相近. 该菌有望用于两步法生物浸出矿物的新工艺.  相似文献   

3.
硫杆菌浸出低品位镍铜硫化矿   总被引:17,自引:4,他引:13  
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.  相似文献   

4.
氧化亚铁硫杆菌的分离培养及其浸磷效果   总被引:5,自引:0,他引:5  
从安徽某煤矿的酸性矿坑水中分离出能有效浸出低品位磷矿的氧化亚铁硫杆菌菌株,对其形态特征和生长特性进行了初步的研究,并通过研究不同固体培养基成分对氧化亚铁硫杆菌分离纯化的影响,确定了适宜的分离条件:9K固体培养基的Fe2+浓度为4.5 g/L,采用下层涂布异养菌(红酵母菌)、上层涂布氧化亚铁硫杆菌的双层平板. 考察了培养基、能源物质及表面活性剂等因素对所选育的氧化亚铁硫杆菌的浸磷效果的影响,通过初步实验,浸磷率可达48%.  相似文献   

5.
低温下氧化亚铁硫杆菌浸出黄铜矿   总被引:3,自引:0,他引:3  
张德诚  朱莉  罗学刚 《化工进展》2008,27(1):125-130
使用中温菌氧化亚铁硫杆菌(Thiobacillus ferrooxidans)在低温条件(8~10 ℃)下浸出黄铜矿.结果表明:经过90d的低温摇瓶浸出后,在无菌硫酸浸出过程中,黄铜矿可以自发氧化分解,最终浸出率为16.08%;在无菌高铁硫酸浸出过程中,由于Fe3 起到了一定的氧化作用,最终浸出率为21.3%;在有菌浸出过程中,氧化亚铁硫杆菌在低温下的浸出率可达37.96%.氧化亚铁硫杆菌在低温下浸出黄铜矿的最适pH值为2.0,在接种量为10%,矿石粒径为0.16 mm,矿浆浓度为2%时较为适宜.在低温浸出的初始阶段,当添加Fe2 的量为6 g/L时能促进浸出率提高最大,最终可达到53.51%.  相似文献   

6.
利用复合添加剂焙烧、低浓度酸浸出法对石煤矿进行提钒研究,考察了焙烧、浸出两个过程中各种工艺参数对浸出率的影响。实验结果表明,适宜的焙烧、浸出工艺条件为:复合添加剂中添加剂硫酸钠、氯化钠、碳酸钠的最佳质量比为7∶1∶11,焙烧温度为750℃,焙烧时间为2.5 h,浸出温度为50℃,浸出时间为5 h。最佳工艺条件下钒的浸出率可达81.9%,明显高于传统的钠法焙烧工艺。  相似文献   

7.
研究了自行选育的氧化亚铁硫杆菌的生长特性。结果表明:我们自行选育培养的脱硫自养菌氧化亚铁硫杆菌,在特定条件下具有快速高效将Fe^2+转化为Fe^3+的功能,通过氧化亚铁硫杆菌生长因素的研究,确定了其生长的最佳条件,即在细菌处于对数生长期时,按10%接种量接种,调节培养液pH为2.5左右,30℃时振荡培养,氧化亚铁硫杆菌的生长活性最佳。通过考察培养过程中Fe^3+浓度的变化,测定了不同接种量时氧化亚铁硫杆菌的氧化性能参数μ。  相似文献   

8.
采用微波辐照对氧化亚铁硫杆菌进行诱变,并利用诱变菌在黄铁矿存在条件下从磷矿粉中浸出可溶性磷.结果表明:800 W微波辐照功率条件下(处理4 min),氧化亚铁硫杆菌浸磷的效果较佳,磷的浸出率达12.25%,比原菌提高了52.74%.通过微波诱变可提高氧化亚铁硫杆菌的氧化活性和产酸量,从而增强磷矿粉中可溶性磷的浸出效果.  相似文献   

9.
为了解决氢氧化镁净化染料废水过程中过滤难的问题,提出了一种球状氢氧化镁的合成方法以及刚果红废水净化处理工艺。采用七水硫酸镁、氢氧化钠和氨水为原料,在晶型控制剂条件下制备球状氢氧化镁,利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)等对产物进行表征。通过振荡实验研究了微孔球状氢氧化镁对水溶液中刚果红的吸附行为,分别考察氢氧化镁加入剂量、时间、溶液p H、振荡转速、温度等因素对吸附效果的影响。研究表明,球状氢氧化镁加入剂量、时间、溶液p H、温度对氢氧化镁吸附刚果红影响较大,振荡转速对其吸附影响较小。同时,在刚果红初始浓度为100mg/L时,得到其最佳吸附工艺条件为:在室温下,微孔球状氢氧化镁的投入量为2g/L,吸附时间为70min,刚果红溶液的p H调节到4~8,吸附振荡转速为220r/min。在此吸附工艺条件,对刚果红初始浓度为100mg/L的吸附率高达93.29%。吸附平衡实验表明,在刚果红废水溶液初始p H为2和吸附温度为40℃时,球状氢氧化镁对刚果红分子的吸附更符合Langmuir模型;刚果红废水溶液初始p H在4~8时,Freundlich吸附模式更适合描述球状氢氧化镁对刚果红的吸附。  相似文献   

10.
对我国某地石煤发电飞灰进行碱浸提钒实验研究,飞灰中的钒主要以V(V)形态弥散于硅、铝氧化物中. 结合钒的赋存形式,考察了反应时间、液固比、碱浓度及温度对钒浸出率的影响. 结果表明,钒浸出率与四因素均呈正比关系. 在搅拌转速500 r/min、180℃、浸出时间3 h、液固比5 mL/g及NaOH浓度200 g/L的最佳工艺条件下,钒浸出率可达85%以上. 浸出液中Al2O3, K, Fe含量分别小于500, 420与9 mg/L. 浸出液返回浸出体系,可充分利用浸出液中富余的碱进一步富集溶液中的钒.  相似文献   

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Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.  相似文献   

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Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.  相似文献   

15.
In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.  相似文献   

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Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.  相似文献   

19.
收集了2007年7月~2008年6月世界塑料工业的相关资料,介绍了2007~2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.  相似文献   

20.
收集了2005年7月~2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。  相似文献   

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