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通过离子交换工艺,去除电解锰工业硫酸锰溶液中的钴镍离子并进行富集。采用6%~10%稀硫酸作为解吸剂,30~50 g/L氨水作为离子交换树脂转型剂,可以将硫酸锰溶液中钴镍离子含量降低到3 mg/L以下,解吸液中钴镍离子含量分别富集了24. 5倍、25. 1倍。离子交换树脂在吸附钴镍离子的同时,对锌铜离子也具有良好的吸附效果,锌铜离子的含量能降低到3 mg/L、1 mg/L以下,有利于硫酸锰溶液的同步净化。 相似文献
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为了解汉中地区绿茶中铜、铁、锰、锌、氟的含量,采用微波消解-原子吸收分光光度法及氟离子选择电极法对汉中绿茶中的铜、铁、锰、锌、氟含量进行了测定。结果显示,汉中绿茶中铜、铁、锰、锌、氟的含量范围分别为66.96μg.g-1,482.30μg.g-1,854.57μg.g-1,89.75μg.g-1,48.6μg.g-1。与文献相比,汉中绿茶中铁、锌含量远高于平均值,锰和铜的含量与平均值相当;氟含量略低于绿茶平均氟含量。 相似文献
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镁合金电沉积镍形成机理及电镀工艺的研究 总被引:1,自引:0,他引:1
分析了浸锌层的作用机理,利用恒电势下电流密度随时间的变化和开路电势随时间变化的曲线,研完了镍在浸锌层上的形成机理.研究发现:镍的电沉积形核过程为连续形核,超电势增加时,晶核数迅速增加;镍层的生长过程遵循VolmerWeber模式;浸锌层能明显改善镀层结合力.在镀镍溶液中加入晶粒细化剂,细化了镀层晶粒,提高了镀层性能.X射线衍射表明:晶粒细化剂加入后,镍层晶粒明显细化,平均柱径约为26 nm,镍层表现为(111)择优取向.纳米晶镍层具有优良的性能,15μm厚的镀层24 h中性盐雾实验的保护等级为9级,热震和划痕试验表明结合力良好. 相似文献
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为提高金属陶瓷铜-铁酸镍的电导率,以氧化镍、三氧化二铁、铜、铁和镍为主要原料,采用两步固相烧结法,制备出铜-镍-铁-铁酸镍金属陶瓷试样。用阿基米德排水法测试样密度,并结合X射线衍射(XRD)和扫描电子显微镜(SEM)分析其微观结构,用四探针法测量了试样的电导率。研究表明,金属铁、镍的加入能够起到晶粒细化、提高致密度的作用,同时使铜与陶瓷的润湿性得到改善,并且有部分金属进入到陶瓷相中。在400~800℃,试样铜-镍-铁-铁酸镍比铜-铁酸镍的电导率有所提高,在960℃下试样的电导率为13.96Ω-1.cm-1。 相似文献
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利用钢板酸洗废液、镍电镀废液、铜电镀废液及锌电镀废液,以适量各废液调配,以ICP-AES检测其浓度,经化学共沉法而获得镍铜锌铁氧磁粉,热处理使晶粒长大,增大模具成型生胚密度,经烧结得环状体,测量其性质,经XRD,SEM,TEM及VSM等检测分析,实验结果显示镍铜锌铁氧磁粉晶体为尖晶石立方结构,晶粒大小为8~20 nm,饱和磁束密度为31.6 emu/g,经过750 ℃热处理饱和磁束密度为52.3 emu/g.烧结环状体晶粒大小为1~3 μm,饱和磁束密度为60.7 emu/g(3670 Gauss). 相似文献
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针对含重金属离子电镀废水,国内外普遍采用化学沉淀法来处理,而化学沉淀法存在运行费用高、二次污染等问题。由于铜离子、锌离子是最常出现在电镀工业中,本文选择铜离子和锌离子为研究对象,本文采用天然沸石处理模拟电镀废水中的铜离子和锌离子,考察了溶液pH值、天然沸石用量、反应时间、共存阳离子等多种物理化学参数的影响。实验结果表明,天然沸石吸附铜离子的最佳参数:当初始浓度为200 mg/L,溶液pH值为7,天然沸石用量为30 g/L,反应时间为20 min时,处理后的水质满足《污水综合排放标准》(GB8978-1996)要求。铜离子分别与锌、镍、铅和六价铬离子共存时,锌和镍离子在低浓度时对铜离子的吸附影响不大;铅和六价铬离子明显抑制铜离子的吸附。天然沸石吸附新离子的最佳参数:初始浓度在200 mg/L,溶液pH值为7,天然沸石用量为30 g/L,反应时间在20 min时,处理后的水质满足《污水综合排放标准》(GB8978-1996)要求。锌离子分别与铜、镍、铅和六价铬离子共存时,铜离子几乎对锌离子无影响;镍离子的影响很小;铅和六价铬离子明显抑制锌离子的吸附,为实际电镀废水的高效处理提供理论依据。 相似文献
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制定了快速测定铜-镍合金镀液中铜和镍的分光光度法。在强碱性条件下三异丙醇胺与铜离子生成稳定的蓝色配合物,与镍离子生成稳定的橙黄色配合物。用光度法在波长430nm处测定镍,铜配离子对测定无影响,可以直接得到镀液中镍的质量浓度。在波长680nm处测定铜和镍的总吸光度,利用已测得的镍的质量浓度用差减法计算铜的质量浓度。镀液中的铁杂质与三异丙醇胺生成无色配离子,不干扰铜和镍的测定,镀液中的配位剂焦磷酸钾及其它组分对测定无影响。实验表明,本法测定铜和镍的相对平均偏差分别为0.85%和1.0%,回收率分别为100.7%和98.3%。本法简练,快速而准确,优于其他方法。 相似文献
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无氰碱性镀铜清洁生产工艺的研究 总被引:4,自引:1,他引:3
借鉴国外先进技术,开发出一种无氰碱性镀铜工艺。讨论了该工艺的镀液组分及操作备件的影响。对镀层外观、沉积速度及镀液分散能力与覆盖能力进行了测试,并与国外某知名品牌的工艺进行了比较。结果表明,这两种工艺性能相当。采用该工艺对3种不同基材电镀无氰碱铜,后镀镍,通过弯曲试验和热震试验检测镀层的结合力,结果发现镀层与基材结合力良好。提出了该工艺镀液的维护与注意事项。该工艺操作简单,控制容易,实际应用效果良好,适合钢铁件、黄铜、锌合金压铸件、铝合金浸锌层的预镀。 相似文献
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Debasis Senapati G. Roy Chaudhury P. V. R. Bhaskara Sarma 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1994,59(4):335-339
Acidic nickel-bearing solution containing iron, cobalt, manganese, zinc and copper was processed through a solvent extraction and precipitation technique to obtain a pure nickel sulphate solution. Iron was extracted using 0.2M Cyanex-272 (partially neutralised) as the extractant. Stripping of iron from the loaded organic has also been studied. After iron recovery through solvent extraction the raffinate still contained 0·25 g dm?3 of iron which was quantitatively separated by a lime precipitation technique. During this iron precipitation there was no loss of cobalt and nickel but copper, manganese and zinc were coprecipitated to some extent. From the iron-free nickel sulphate solution the other impurities were extracted using the same extractant (Cyanex-272) in a single stage. The metal ions from the loaded organic were stripped using a 0·5% (v/v) H2SO4 solution in a single stage. The entire operation needs only seven stages: two stages for iron extraction, three stages for iron stripping from the loaded organic, and one stage each for extraction and stripping of other impurities. In the entire operation the loss of nickel was less than 0·5%. 相似文献
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R. E. F. Einerhand W. H. M. Visscher E. Barendrecht 《Journal of Applied Electrochemistry》1988,18(6):799-806
The determination of the amount of hydrogen produced during the electrodeposition of zinc from alkaline zincate solutions was carried out using the rotating ring-disc electrode (RRDE) technique. The experimental conditions for which the RRDE technique offers reliable results are discussed. Hydrogen production during zinc deposition was studied for a range of cathodic (disc) current densities (20–500 A m–2) and electrolyte compositions (1–7 M KOH, 0.01–0.2 M zincate). It was found that an increasing amount of hydrogen was formed with increasing (disc) current density and decreasing KOH and zincate concentration. The impact of hydrogen formation during the charging process on nickel oxide/zinc secondary battery performance is expected to be small. It is concluded that in battery electrolytes (8 M KOH, 1 M zincate) hydrogen is formed chiefly by corrosion of the zinc electrode rather than by electrochemical formation during the electrochemical reduction of zinc. 相似文献
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Kolesnikov A. V. Vorob’eva O. I. Kapustin Yu. I. 《Theoretical Foundations of Chemical Engineering》2011,45(5):794-799
This work is devoted to the electroflotation purification of wastewater from copper and nickel ions in the presence of surface-active
compounds (SACs) and oil. The kinetics of these processes were studied. It was shown that the presence of oil decelerates
the initial stage of the process of extraction of nickel(II) and copper(II) hydroxides. SACs do not affect the extraction
of copper hydroxide and the process is intensified for nickel hydroxide. The possibility of extracting metal ions as phosphates
was demonstrated. 相似文献
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Addition of zincate to the leach liquor for the preparation of skeletal copper increases the copper surface area; however it does not stabilize the structure against rearrangement. The leaching kinetics have been studied using a rotating disc electrode (RDE) at 269–293 K in 2–8 M NaOH and 0.0005–0.1 M Na2ZnO2. Zincate ions precipitate as zinc oxide, due to the local consumption of hydroxide ions near the leach front as the aluminium dissolves. This oxide hinders the aluminium dissolution, slowing the leaching rate. It also hinders copper dissolution/redeposition and prevents copper diffusion, thus reducing the structural rearrangement significantly, and causing the formation of a much finer copper structure with increased surface area. The zinc oxide redissolves as the leach front passes, releasing the copper to rearrange once more, thereby allowing the surface area to decrease with time. The activation energy for leaching was found to be 84 ± 6 kJ mol–1. 相似文献
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铁氧体法去除废水中的镍、铬、锌、铜离子 总被引:2,自引:0,他引:2
采用铁氧体法处理含镍、铬、锌、铜的废水,研究了pH及硫酸亚铁投加量对重金属离子去除效果的影响.对于镍、锌、铜离子,最佳絮凝pH分别为8.00~9.80、8.00~10.50和10.00,投加的亚铁离子与其摩尔比均为2~8;六价铬的最佳还原pH为4.00~5.50,最佳絮凝pH则为8.00~10.50,最佳投料比为20.... 相似文献