各种电镀槽液的管理和处理方法

电镀槽液的管理和处理方法是决定电镀厂产品质量和经济效益的重要手段。为此,本文详细论述了各种电镀槽液的处理方法,其中包括1,除油槽液的处理,2,氰化物镀铜或铜锡合金槽液的处理;3,镀镍槽液的处理;4,镀铬槽液的处理;5,镀锌槽液(氨三乙酸-氯化铵镀液和氰化镀锌槽液)的处理。特别是对镀镍槽液的处理,不但论述了常规处理方法还论述了镀镍槽液的大处理方法,考虑到可能存在杂质的情况,分别论述了当含有铁、铬、铜、胶体杂质时的处理方法,对电镀厂的质量管理和故障处理将有参考价值。     

电沉积铂研究Ⅰ--工艺条件与镀层性能

研制了2种新的电沉积铂镀液体系：新槽液Ⅰ号和Ⅱ号。通过实验研究了电流密度、温度和主盐含量对镀液电流效率的影响,并与常用的碱性P盐槽液、酸性P盐槽液和DNS槽液进行对比。结果发现：新槽液Ⅰ号在电流密度为2A／dm^2、工作温度为30～40℃以及主盐含量为4～10g/L时,电流效率较高,从而可以在较低的温度下实现光亮镀铂。分散能力实验表明,新槽液Ⅰ号具有良好的分散能力。扫描电镜(SEM)图和X射线晶体衍射(XRD)图也证明,与传统的可获得色泽最白、性能最优的镀层的DNS槽液相比,新槽液Ⅰ号获得的镀层对晶面的择优程度与DNS槽液相近,但其内应力更小、表面更平整、结晶更细致、厚度更大。     

横管初冷器排液系统的改进

我厂新建的焦炉煤气净化装置中,鼓风冷凝工段采用了五台横管初冷器。初冷器中段的冷凝液经5个中段水封槽后自流入中段冷凝液槽;下段的冷凝液经5个下段水封槽后自流入下段冷凝液槽,再经满流进入中段冷凝液槽中,中段冷凝液槽中的冷凝液用泵送至焦油除渣器处理。 由于上述排液流程存在管线复杂、占地面积大、生产操作麻烦和检修困难等问题,我们根据以往的操作经验对其进行了改进,取得了较好的效果。 我们取消了5个初冷器中段水封槽、1个50m~3的中段冷凝液槽及两台中段冷凝液泵。将     

信息动态

0 前言 低氢脆镀镉被广泛应用于航空领域.槽液状况直接决定镀层质量.槽液成分比较复杂,包括氰化钠、氧化镉及氢氧化钠等.如果日常维护不到位,槽液会发生恶化.废弃的槽液不能直接排放,必须经过严格处理,需要花费大量的人力和物力.如何维护好镀镉槽液,对于提高产品质量、降低成本及环境保护等具有重要意义.本文将低氢脆镀镉槽液的恶化原因及维护措施阐述如下.     

低氢脆镀镉槽液恶化原因及维护

<正>0前言低氢脆镀镉被广泛应用于航空领域。槽液状况直接决定镀层质量。槽液成分比较复杂,包括氰化钠、氧化镉及氢氧化钠等。如果日常维护不到位,槽液会发生恶化。废弃的槽液不能直接排放,必须经过严格处理,需要花费大量的人力和物力。如何维护好镀镉槽液,对于提高产品质量、降低成本及环境保护等具有重要意义。本文将低氢脆镀镉槽液的恶化原因及维护措施阐述如下。1低氢脆镀镉槽液恶化原因(1)化学药品和水质不纯。     

沼气脱硫富液槽液位合理波动范围分析

沼气吸收法脱硫过程中,带有流量循环式双容器串联性质的脱硫塔和富液槽的液位可以采用间接控制方法。通过采用富液和贫液的流量比值控制,并研究富液槽液位波动合理的范围,找到其液位波动动态平衡点,实现对脱硫塔、富液槽液位均匀控制的目标。消除富液槽满罐或排尽的现象。针对当前的工艺设备参数进行研究计算得出结论:流量比值系数理论上为1;富液槽液位的合理波动范围在0.264m。     

国内文献摘要

<正>改进的乙二醇生产系统一种改进的乙二醇生产系统,包括第一乙二醇液封槽、第二乙二醇液封槽、第三乙二醇液封槽、第四乙二醇液封槽、蒸发器、乙二醇低点收集槽、分离塔、回用乙二醇收集槽及浆料配制罐;所述蒸发器的出口和回用乙二醇收集槽的之间的管路上设有第一换热器,而新鲜乙二醇的管路则通过前述的第一换     

氨基磺酸镍电铸层产生针孔、麻点的原因分析及工艺改进

通过对比试验对润湿剂、金属离子杂质、有机物杂质、槽液pH以及固体颗粒物等因素进行排查,得出氨基磺酸盐电铸镍层产生针孔、麻点的原因,并提出相应的工艺改进措施。槽液中存在固体颗粒和槽液pH不在工艺范围内是造成镀层表面针孔和麻点的主要原因。为保证产品质量,电铸时应采用精密循环过滤系统对电铸槽液进行连续净化并控制槽液pH在允许的工艺范围内。     

沟槽参数对螺旋槽液膜密封空化诱发影响分析

为进一步探索液膜密封端面空穴发生诱因及其影响规律,本文基于JFO（Jakobsson-Floberg-Olsson）空化边界,建立双坝区中间开螺旋槽的液膜密封物理模型,通过空穴可视化实验验证了程序算法的准确性,分析了不同空化边界下液膜密封的空穴特征。以密封面间润滑液体的液膜压力和密度变化为判据,探讨了槽深、槽角和槽数等参数对液膜始破位置、重生位置及空穴发生面积的影响。结果表明：相比Half-Sommerfeld和Reynolds空化边界,基于JFO空化边界计算的空穴特征能更好地与实验结果相吻合;较大槽深和槽数,均缩小了液膜始破位置沿螺旋方向的空穴长度和液膜重生位置沿周向的空穴宽度,前者提升了两位置的空穴度,而后者降低了液膜重生位置的空穴度;槽角的增大,在扩大两位置空穴尺度的同时,提升了相应位置的空穴度;而液膜中空穴发生面积随槽深的增加线性降低,在较小槽角时先线性增加后随槽角增大呈抛物线增加趋势,而在槽数大于12时随槽数增加线性降低。     

湿式氧化法脱硫的问题讨论（下）

6富液槽的设置 设置富液槽的必要性已被重视，尤其二元催化法半脱富液槽的设置对副盐的生成影响极大。根据栲胶法开发专家的意见：富液槽的容积应达到溶液停留时间〉20min时，HS一与氧化态析硫反应才能大部分完成，富液槽的容积因为催化剂的析硫反应速度有所不同而对容积的要求也不同。     

钾盐对氰化镀铜溶液性能的影响

研究了钾盐对氰化镀铜溶液性能的影响,结果表明,向镀液中加30～60 g/L的硫酸钾,能够明显提高镀层的光亮度和镀液的覆盖能力,当采用较低质量浓度氰化镀铜溶液时,硫酸钾能够提高镀液的分散能力.生产实践表明:在挂镀氰化镀铜槽中用硫酸钾取代有机光亮剂能够提高镀层与基体之间的结合力.     

影响化学镀镍液活性的研究

通过实验研究了在中温碱性化学镀镍溶液体系中,影响碱性化学镀液活性与寿命的最主要因素不是亚磷酸根的累积,而是镀液中铵盐的累积.通过采用不合铵盐的碱替代氨水来调节镀液pH值的方式,能有效地控制镀液中铵盐的累积,有效地延长了镀液的使用寿命.     

阴极电泳涂料槽液细菌含量的测定与防治

采用了细菌测试片法检测阴极电泳涂料槽液中的细菌含量,该方法能够快速准确地检测出槽液细菌的含量,并采用相应的杀菌剂进行杀菌。同时对杀菌前后的槽液进行了性能对比试验。     

Effect of surfactant on morphology and pore size of polysulfone membrane

The skin layer structure can be changed by adjusting the diffusion rate of the non-solvent into the polymer solution between membrane and coagulation bath through adding surfactant into either coagulation bath or dope solution. When adding SDS in coagulation bath, the variation trend of apparent diffusion coefficient during phase separation and scanning electron microscopy morphology of resultant membranes indicated that, at the beginning SDS migrated to the membrane-bath interface during phase separation process, playing a role as mechanical barrier within 0.15 wt% SDS concentration. Once the SDS concentration exceeds CMC, the remaining SDS will form micelles act as a carrier, hence, the phase separation rate accelerated. The membranes were characterized roughness parameters, obtained by the atomic force microscopic technique. While adding surfactant in the dope solution, compared with SDS addition into the coagulation bath, apparent diffusion coefficient and SEM morphology showed the similar trend, and the excellent range of SDS concentration is 0.08 wt%-0.1 wt%. As changing the nature of surfactant in the dope solution, we found that, with the increase of surfactant hydrophile-lipophile balance (HLB) value, the rate of phase separation speeds up, the size of macrovoid increases, flux increases gradually and rejection is weakened.     

Effect of EDTA concentration on the physical and optical properties of Cds thin films

Application of ethylenediamine tetraacetic acid (EDTA) in the chemical bath solution to enhance the physical and optical properties of chemical bath deposited CdS film was realised. The observed beneficial effect on the crystallisation of CdS crystallites in the bath solution followed by deposition on glass substrates reduces the amorphousity and enhances the crystallinity of the film. The optical transparency of the film attains a maximum of 80% over the wavelength range of 650–1100 nm for the film deposited from EDTA‐added solution having the concentration of 0.006 mol/L. Also, the observed intensity of the characteristic photoluminescence emission was found to be dependent on the concentration of EDTA in the bath solution. © 2011 Canadian Society for Chemical Engineering     

Pore generation in asymmetric polymeric membranes Correlation with solvent mobilities

Summary Analyzing videomicroscopy observations, this work deals with macrovoids detected through the skin of asymmetric polymeric membranes. The circle-like images of the macrovoids were found to form two-dimensional random patterns ; these were characterized from the mean distance, <λ>, determined between nearest neighboring images. Starting from polyetherimide or polyacrylonitrile solutions, each solution cast as a film was immersed in a water bath, at room temperature ; <λ> was shortened either by increasing the solvent concentration in the casting solution or by decreasing the solvent concentration in the bath (non-solvent of the polymer). This study was based on the assumption that the formation of the macrovoid pattern may be correlated to the interface instability resulting from the current of solvent diffusing towards the bath and initiated by the immersion of the polymer solution. Master curves, involving <λ>, the solvent concentrations in the polymeric solutions or in the bath and the solvent diffusion coefficients, measured prior to the immersion of the solution in the bath, were drawn. Diffusion coefficients were measured using a pulsed magnetic field gradient method. Received: 6 November 1998/Revised version: 9 February 1999/Accepted: 9 February 1999     

Electrowinning/Electrostripping and Electrodialysis Processes for the Recovery and Recycle of Metals from Plating Rinse Solutions

Abstract

Two electrochemical-based methods have been evaluated to remove heavy metals from a tin/zinc electroplating rinse solution with subsequent recycle of the metals back into the original plating bath. The first method uses electrodialysis to move tin to the anolyte strip solution as an anionic citrato complex while zinc is distributed to both the anolyte and catholyte, showing it exists as both an anionic citrato complex and in free cationic form. Zinc can be recovered by scraping the loose deposit from the cathode and dissolving it in mineral acid.

The second method is a combined electrowinning/ electrostripping technique. The process involves continuously flowing the plating rinse solution through a porous graphite cathode and removing the metal ions via electrodeposition. When a sufficient quantity of metal has been deposited, the electrode is placed in a solution whose chemical composition is similar to that of the original plating bath and the metals ions are stripped from the electrode anodically. The resulting solution is then placed into the original plating bath.

Both methods were used to treat a surrogate rinse solution originally containing 100–300 parts per million of each metal and were successful in reducing the metal-ion concentrations to less than 15 parts per million each. Approximately 70% of the tin and 100% of the zinc are recoverable by either method.     

Study on the control of pore sizes of membranes using chemical methods: Part III. The performance of carbonates and bicarbonates in the membrane-making process by the chemical reaction

In this paper, polyvinylidene fluoride (PVDF)/polymethyl acrilate (PMMA)/cellulose acetate (CA) blend UF membranes were prepared by chemical reaction introduced phase-inversion method. The results of the experiment show that: (1) The membrane pore size distribution is more uniform due to the presence of carbonates or bicarbonates in the coagulation bath; (2) No more than the stoichiometric ratio amount of carbonates or bicarbonates in the coagulation bath can effectively improve the membrane pore size distribution and make the pore size of membrane more uniform; (3) The membrane prepared by carbonates solution as a working solution in coagulation bath possess superior performance than that by bicarbonates.     

Causes of the appearance of adhesions in the formation of cuprammonium staple fibre

Conclusions 1. It has been shown that the content of ammonia in the spinning solution and the coagulation bath, the content of sodium sulphate in the coagulation bath, and the rate of its feed to the spinning unit affect the adhesivity of cuprammonium staple fibre.2. To decrease the number of adhesions in the fibre it may be recommended that the ratio of ammonia to cellulose in the solution should be kept between 0.48 and 0.50, the content of ammonia in the coagulation bath should be not more than 0.05 g/litre and that of sodium sulphate 1.2–1.5 g/litre, and the rate of feed of the bath should be 18–20 litres/min.We express our thanks to Prof. A. B. Pakshver for valuable advice in the performance of this investigation.Ivanov Chemical and Technological Institute (IKhTI); Shui Factory. Translated from Khimicheskie Volokna, No. 3, pp. 41–42, May–June, 1969.     

Preparation and properties of conductive polyaniline/poly‐ω‐aminoundecanoyle fibers

Historically, polyaniline (PANI) had been considered an intractable material, but it can be dissolved in some solvents. Therefore, it could be processed into films or fibers. A process of preparing a blend of conductive fibers of PANI/poly‐ω‐aminoundecanoyle (PA11) is described in this paper. PANI in the emeraldine base was blended with PA11 in concentrated sulfuric acid (c‐H₂SO₄) to form a spinning dope solution. This solution was used to spin conductive PANI / PA11 fibers by wet‐spinning technology. As‐spun fibers were obtained by spinning the dopes into coagulation bath water or diluted acid and drawn fibers were obtained by drawing the as‐spun fibers in warm drawing bath water. A scanning electron microscope was employed to study the effect of the acid concentration in the coagulation bath on the microstructure of as‐spun fibers. The results showed that the coagulating rate of as‐spun fibers was reduced and the size of pore shrank with an increase in the acid concentration in the coagulation bath. The weight fraction of PANI in the dope solution also had an influence on the microstructure of as‐spun fibers. The microstructure of as‐spun fibers had an influence on the drawing process and on the mechanical properties of the drawn fibers. Meanwhile, the electrically conductive property of the drawn fibers with different percentage of PANI was measured. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1458–1464, 2002