12 resultados para spent zinc manganese dioxide batteries

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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我国电池生产量已经达到209亿节(2003年),多年来一直占据世界第一大电池生产国的地位,其中锌锰电池占大多数。废锌锰电池丢弃后,其中的重金属物质会逐渐渗透到地下,污染土壤和水体。重金属在生物体内富集,会使生物体致畸或致变。但同时,废锌锰电池中也含有大量有用的资源如锌、二氧化锰等。应对其进行回收利用,变废为宝。本文介绍了废锌锰电池回收处理的主要技术及研究进展,不同的处理技术回收废锌锰电池时的目标产物各不相同,但一般可分为以下几种:以单质形式回收锌、锰和汞;以合金的形式回收锌和锰;回收锌和二氧化锰;回收各金属元素制备复合微量元素肥料;回收锌、锰元素制备锰锌铁氧体;回收锌、锰元素制备硫酸锌和碳酸锰等。本文对一些废锌锰电池回收处理技术的优缺点从无害化程度、资源化程度、产品等级、工艺要求以及二次污染五个方面进行了分析和比较。在对国内外废锌锰电池回收处理技术进行分析比较的基础上提出了一种成本较低、可操作性较强的处理技术:先以干法除去废锌锰电池中的汞,然后以湿法除去其它的有害重金属并进一步加工制备有机螯合微量元素肥料。 本文以回转窑中物料停留时间的经验公式和传热学的知识设计和计算了回转窑的长度和内径尺寸、电热丝的功率以及外围的保温材料厚度等参数。用保温材料和润滑油相结合的方式对回转窑的连接部分实行密封。通过调整回转窑的转速和回转窑支架两端高度差的方式控制物料在回转窑中的停留时间,从而调节热解时间的长短。利用自动控制设备调节电热丝的功率从而调节试验中的热解温度。利用该回转窑在不同条件下对热解处理废锌锰电池进行了试验研究,热解过程中产生的尾气和颗粒物用一系列吸收液进行吸收和固定。 在热解试验中改变影响热解过程的三种因素:热解温度、热解时间和载气流速并按三因素四水平的正交方法安排试验。改变废锌锰电池热解过程中的热解温度、热解时间和载气流速三种因素进行正交试验并利用正交统计学的方法分析了这三种因素对热解除汞率的影响。利用ICP检测仪测定了各吸收液中汞的含量,并分析热解气体产物经过系列吸收液时汞被吸收的情况以及汞的形态分布。利用气相色谱仪对尾气成分进行了测定,并对热解过程中产气的过程和规律进行了分析。用X射线衍射测试的方法研究了热解前后锌锰电池的物质形态变化情况。对除汞率的正交统计分析表明,合适的热解条件为:热解温度690℃,热解时间100min,载气流速0.06m3/h,在这种试验条件下热解处理废锌锰电池的除汞率达到100%。同时还得到:热解时间对除汞效果影响最大,热解温度次之,载气流速的影响较小。ICP测试的结果表明:热解尾气在经过试验中设置的吸收瓶后,其中的汞被完全吸收,尾气中95%以上的汞以单质的形式存在。气相色谱分析的结果表明,热解开始后,废锌锰电池中的有机质迅速分解,其产物为C2H4、CH4和H2等。一段时间后,有机质的分解量大幅度减少,同时废电池中的石墨碳和高价金属氧化物发生氧化还原反应,生成CO气体。对废锌锰电池原料以及热解残渣的X射线衍射分析表明,当热解温度为350℃时,X射线衍射图谱上2θ值为35°附近的区域有新峰出现,但不明显,说明有结晶体形成但量不大。500℃时上述峰明显增强,这是由于ZnO和FeO形成了结晶体,同时在2θ值为41°附近有新峰出现,这是高价锰氧化物与石墨碳发生氧化还原反应生成了MnO并形成了结晶体。650℃时,2θ值在41°附近的峰显著增强,且热解过程中形成的峰稳定下来,基本上不再有新的结晶体生成。热解后,高价锰氧化物的相对含量从32.2%下降到4.6%,而MnO的相对含量则从6.4%上升到38.6%。热解后的残渣中晶体物质含量大,金属元素大多以低价态存在,适合于制备有机螯合微量元素肥料。

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Different effects of divalent metal ions on electrochemiluminescence (ECL) sensor with Ru(bPY)(3)(2+) immobilized in Eastman-AQ membrane were investigated. Mg2+,Ca2+ and Fe2+ can elevate the ECL of Ru(bpY)(3)(2+)/proline; while metal ions that underwent redox reactions on the electrode such as Mn2+ and Co2+ presented intensive quenching effects on Ru(bpy)(3)(2+) ECL. Also, the quenching effect of Mn2+ on the ECL sensor with Ru(bpY)(3)(2+) immobilized in Eastman-AQ membrane enhanced to about 30-folds compared with the case that Ru(bpy)(3)(2+) was dissolved in phosphate buffer, and the enhanced quenching effects of Mn2+ were studied.

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A copper/zinc superoxide dismutase (Cu/ZnSOD) gene and a manganese superoxide dismutase (MnSOD) gene of the human parasite Clonorchis sinensis have been cloned and their gene products functionally characterized. Genes Cu/ZnSOD and MnSOD encode proteins of 16 kDa and 25.4 kDa, respectively. The deduced amino acid sequences of the two genes contained highly conserved residues required for activity and secondary structure formation of Cu/ZnSOD and MnSOD, respectively, and show up to 73.7% and 75.4% identities with their counterparts in other animals. The genomic DNA sequence analysis of Cu/ZnSOD gene revealed this as an intronless gene. Inhibitor studies with purified recombinant Cu/ ZnSOD and MnSOD, both of which were functionally expressed in Escherichia coli, confirmed that they are copper/zinc and manganese-containing SOD, respectively. Immunoblots showed that both C. sinensis Cu/ZnSOD and MnSOD should be antigenic for humans, and both, especially the C. sinensis MnSOD, exhibit extensive cross-reactions with sera of patients infected by other trematodes or cestodes. RT-PCR and SOD activity staining of parasite lysates indicate that there are no significant differences in mRNA level or SOD activity for both species of SOD, indicating cytosolic Cu/ZnSOD and MnSOD might play a comparatively important role in the C. sinensis antioxidant system.

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An experimentally simple and inexpensive catalyst system based on hexabutylguanidinium/ZnBr, has been developed for the coupling of carbon dioxide and epoxides to form cyclic carbonates with significant catalytic activity under mild reaction conditions without using additional organic solvents (e.g. the turnover frequencies (TOF, h(-1)) values as high as 6.6 x 10(3) h(-1) for styrene oxide and 1.01 x 10(4) h(-1) for epichlorohydrin). This catalyst system also offers the advantages of recyclability and reusability. Therefore, it is a very effective, environmentally benign, and simple catalytic process. The special steric and electrophilic characteristics of hexabutylguanidinium bromide ionic liquid result in the prominent performance of this novel catalyst system.

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Various organometallic compounds (diphenylzinc, dibenzylzinc, dicyclohexylzinc, bis( pentafluorophenyl) zinc, diethylzinc, di(n-butyl) zinc, triethylaluminum) were used to form Y(CCl3COO)(3)-organometallic compound-glycerol catalyst for the copolymerization of carbon dioxide and propylene oxide. It was found that Y(CCl3COO)(3)-diphenylzinc-glycerol catalyst showed the highest catalytic activity, at optimum conditions the yield could be as high as 478.8 ( g polymer/mol Zn h).

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A series of single-component cobalt salen complexes, N,N'-bis(salicylidene)-1,2phenylenediamino cobaltIII X(X = Cl (1a), Br (1b), NO3 (1c), CF3COO (1d), BF4 (le), and N3 (If)) (SalphCoX), were prepared for alternating copolymerization of carbon dioxide and propylene oxide(PO) under mild condition. The axial anion X group of the SalenphCoX played important role in tailoring the catalytic activity, polymeric/cyclic carbonate selectivity, as well as stereochemistry of carbonate unit sequence in the polymer chain. SalenphCoX with an electron-withdrawing axial X group (complex 1c) was an ideal catalyst for the copolymerization of CO2 and PO to selectively produce polycarbonate with similar to 99% carbonate linkage and over 81% head-to-tail structure.

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Reactions of Ln(III) acetate (Ln = Pr and Nd) and a polydentate Schiff-base in a mixture of methanol and acetonitrile resulted in the unprecedented assembly of novel Ln(10) aggregates containing two Ln(5) pentagons templated by mu(5)-CO32-, introduced via spontaneous fixation of atmospheric carbon dioxide. Magnetic analysis using an expression including the ligand field effects and molecular field approximation indicates weak antiferromagnetic coupling between the metal ions. This synthetic approach may represent a promising new route toward the design of new lanthanide clusters and novel multifunctional materials.

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Samarium and manganese co-doped zinc borosilicate storage glasses were prepared by high temperature solid state method. The effect of doping samarium on the defect of Mn activated sample was studied by means of thermoluminescence spectra. It was found that the shallower traps of the sample predominate with the addition of samarium, as a result, the phosphorescence and storage properties of the manganese doped zinc borosilicate glasses were greatly changed.