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讨论了氯化外镀锌溶液中杂质铁离子对镀液性能及镀层质量的影响,试验结果表明:Fe^2+可以与Zn^2 共同电沉积,而不影响镀层的外观质量,Fe^2 逐渐被氧化,生物Fe(OH)3的沉淀,使镀层粗糙,介绍了几种污染镀液的处理方法,大处理,铁离子沉淀剂,络合剂,还原剂方法。 相似文献
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分别以PEG-1000、β-环糊精和吐温-60等为助络合剂,采用不同工艺方法制备了具有不同结构的双金属氰化物络合物(DMC)催化剂,研究了不同助络合剂和不同制备方法对DMC催化剂的形貌、粒径、晶型结构和催化活性的影响.结果表明以PEG-1000、β-环糊精和吐温-60等为助络合剂,利用传统制备方法可以获得晶态与非晶态组分混合物的DMC催化剂.而将助络合剂提前加入到钾盐和锌盐溶液中,可制备出高度分散的非晶态的DMC.这种非晶态的DMC催化剂活性高,反应速度快,其催化性能明显优于利用传统制备方法制备的DMC. 相似文献
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维尔希-100是一新型络合剂,对金属铁离子具有很强的络合能力。在冷却水系统清洗过程中投加适量的维尔希-100有助于提高清洗金属腐蚀产物和垢物的现场效果。 相似文献
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一、前言在聚氯乙烯悬浮聚合中,络合剂的加入,既可消除聚合体系中金属离子(特别是铁离子)对提高聚合速率导致产品质量降低的影响;又可防止水合铁离子静电吸附在PVC粒子空穴中影响树脂加工质量;另 相似文献
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《硅酸盐学报》2016,(10)
以马来酸、甘氨酸或柠檬酸作为络合剂,采用溶胶-凝胶法制备锂离子电池Li Ni0.80Co0.15Al0.05O_2正极材料,对比了络合剂种类对样品电化学性能的影响。结果表明:采用不同络合剂制备的样品都具有层状结构,以柠檬酸为络合剂制备的样品存在较多的八面体单晶体。电化学分析显示,以马来酸为络合剂制备的样品具有最佳的充放电和循环性能:0.2C下首次放电容量为176 m A·h/g,30次循环后容量保持率为97.3%;1C下首次放电容量为162 m A·h/g,30次循环后容量保持率为92.3%。根据循环伏安曲线得到的锂离子的扩散系数表明,采用马来酸为络合剂制备的样品具有最大的扩散系数。 相似文献
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利用传统方法分析镍-铁合金镀液中的硼酸,镀液中亚铁离子会严重影响测定结果。介绍了一种方法,用过硫酸钠氧化镀液中的亚铁离子和络合剂,再用氢氧化钠沉淀出铁离子和镍离子,过滤后用硫酸酸化试液,以甲基红为指示剂,用碱中和过量的硫酸。最后用甘露醇与硼酸反应生成较强的络合酸,以酚酞作指示剂,用氢氧化钠标准溶液滴定。这种方法分析结果较准确,能够满足监控镀液中硼酸的要求。 相似文献
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为制备高纯稀土,降低非稀土杂质铁含量,对添加环烷酸的N235萃取分离铁进行了实验研究.Fe(II)的萃取率随有机相N235浓度增加、环烷酸添加量减少及水相酸度增加而增加.添加少量环烷酸的N235萃取剂基本不萃取料液中的稀土,但料液中稀土的存在有助于铁萃取.经过7级逆流萃取实验,REO中的Fe2O3由0.58%降到10-6. 相似文献
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A novel preparation method of polyaluminum chloride/polyacrylamide composite coagulant: Composition and characteristic
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Xiaoping Wang Xiaomin Tang Ping Feng Xinyu Li Chuanliang Zhao Wei Chen Huaili Zheng 《应用聚合物科学杂志》2017,134(11)
Inorganic/organic composite coagulants have drawn a wide attention through the years owing to its superior coagulation behaviors. In this study, polyaluminum chloride (PAC)/polyacrylamide (PAM) composite coagulant was synthesized by ultraviolet (UV) irradiation by using PAC and acrylamide (AM) as raw materials, urea as a solubilizer, and 2,2′‐Azobis[2‐(2‐imidazolin‐2‐yl)propane]dihydrochloride (VA‐044) as an initiator. The effect of total monomer mass fraction, solubilizer dosage and initiator dosage on the viscosity and molecular weight of PAC/PAM composite coagulant was discussed. The results suggest that the composite coagulant with high polymerization degree, intrinsic viscosity of 1483 mL/g and molecular weight of 7.38 million, could be obtained when the total monomer mass fraction of 40%, urea dosage of 1.5% and initiator dosage of 0.6% are chosen in the preparation. It is a potential preparation method of composite coagulant with short preparation time and high preparation efficiency. Fourier transform infrared spectrum and 1H nuclear magnetic resonance spectroscopy represent that the coagulant for polyaluminum chloride and polypropylene are copolymer. Thermal gravimetric analysis describes the high thermal stability of composite coagulant. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44500. 相似文献
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黄凤妹 《化学工业与工程技术》2011,32(6):11-13
活性炭生产中用磷酸液进行活化,磷酸液可重复回收利用。由于木屑、炭屑等原材料的影响,用于反复活化浸渍的磷酸液中铁质量分数将从小于10×10-6上升到数百×10-6,甚至更高,不能满足医药、食品等行业对铁离子含量要求较高的活性炭生产之需。采用二甲基肼、15%磷酸液、二硫化碳3种药品于一定条件下反应,制得了螯合络合沉淀剂,于常温下可将回收来的磷酸母液中的铁离子除去,除铁效果显著,达到50×10-6以下,从而使回收的磷酸液满足医药、食品等行业用活性炭的生产要求。该法工艺简单、成本低,且不引入杂质离子,是一种值得推广的应用技术。 相似文献
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介绍了一种全新的方法-粘度法研究水处理混凝剂(聚合氯化铝)在水溶液中的形态的原理和方法,求得水化离子团特征值A2,从而为进一步摸清聚合氯化铝在水溶液中的形态奠定了基础,为开发新型高效混凝剂提供有指导意义的信息。 相似文献
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The effect of hydrogen chloride on the decomposition of poly(vinyl chloride) (PVC) has been studied and a mechanism for the autocatalysis is given. The chloride ion formed upon dissociation of the hydrogen chloride is a strong base in the medium of the reaction, and hence constitutes the active species. Therefore, the acceleration of the decomposition of PVC can be prevented by either removing the free acid from the system with the aid of an acid acceptor or adding a complexing agent such as ferric chloride. 相似文献
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Lim-Seok Kang Seung-Woo Han Chul-Woo Jung 《Korean Journal of Chemical Engineering》2001,18(6):965-970
This research explored the feasibility of preparing and utilizing preformed polymeric solution of Al(III) and Fe(III) as coagulants
for water treatment. The differentiation and quantification of hydrolytic Al and Fe species in the coagulants were done by
utilizing spectrophotometric method based on the interaction of Al or Fe with ferron as a complexing agent. In addition, 27A1-NMR,
FT-IR, and powdered XRD were used to characterize the nature and structure of the hydrolytic species in these coagulants.
The properties of the polyaluminum chloride (PAC1) and polymeric iron chloride (PIG) showed that the mass fractions of the
maximum polymeric Al produced at r(OH/Al)=2.2 and Fe at r=1.5(OH/Fe) were 85% and 20% of the total aluminum and iron in solution,
respectively. Coagulation tests were conducted under various coagulant dosages and pHs for each coagulant prepared. In case
of PAC1 coagulants, a coagulation test on Nakdong river waters with three PACls (r=2.0, 2.2, 2.35) showed that the effectiveness
of coagulation was in the order, r=2.2>2.0>2.35, corresponding to the order of polymeric aluminum contents. And, for the PIC1
coagulants, the PIC1 of r=1.5 was most effective for the removal of turbidity and TOC from the raw water.
Presented at the Int’l Symp. on Chem. Eng. (Cheju, Feb. 8–10, 2001), dedicated to Prof. H. S. Chun on the occasion of his
retirement from Korea University. 相似文献