阴极电泳漆槽液熟化周期研究

针对槽液熟化周期长的电泳漆品种,在进行电泳漆材料性能试验时提前将电泳漆中的乳液进行深度脱溶剂处理,除掉其中大部分的低沸点溶剂,可以有效缩短电泳漆槽液的熟化周期,在短时间内满足电泳漆的相关试验需求。     

车身电泳缩孔产生原因分析与防治

针对涂装电泳车身出现批量小缩孔问题,经挂板试验分析、实车生产验证和槽液取样送检分析,确定电泳小缩孔是因电泳槽液老化和长菌导致.通过电泳倒槽、补充新电泳树脂和溶剂、添加药剂等手段,改善了槽液参数指标,提升了电泳漆膜的外观质量和防腐蚀性能,为延缓槽液老化的速度和改善生产工艺的现场管理提供参考.     

核燃料后处理厂泵轮式混合澄清槽的选型与设计

核燃料后处理厂中通常采用混合澄清槽作为铀纯化流程和溶剂循环流程的液-液萃取设备。与普通的机械搅拌混合澄清槽相比,泵轮式混合澄清槽具有设备紧凑、易于进行放大设计等优点,因此在国外核燃料后处理厂中广泛使用。文章简要介绍了KAPL型、KREBS型、PowerGas型以及法国后处理厂使用的泵轮式混合澄清槽;通过比较几种混合澄清槽的优缺点,分析适用于我国核燃料后处理厂的泵轮式混合澄清槽的结构形式,并对泵轮式混合澄清槽进行简略设计。     

国外电镀环保文摘

[H79] 电渗析与金回收——闭路循环探讨 Electrodialysis and gold recovery——A closedloop appaoach:J.S.Lindstedt:Plat.Surf.Finish.,69(7),p.32-36,1982. 采用电渗析、离子交换、逆流清洗和过滤技术,使装饰镀金线实现闭路循环。电渗析器间歇处理氰化镀金静态清洗槽槽液、酸性镀金的静态清洗槽槽液及其冲洗槽槽液,金的回收率达95％,并去除了槽液中的杂质。采用脱盐水补充镀槽水分损失。三槽式逆流清洗水由第一清冼槽引出,经精密过滤和复床式离子交换后,处理水作为脱盐水回用于镀件清洗。离子交换     

槽液中助溶剂对电泳漆膜质量及环境的影响

使用正交试验法对电泳槽液中助溶剂的组成与配比进行优选.槽液中助溶剂组成与配比的变化对电泳漆膜的外观质量及环境有较大的影响.     

影响电泳泳透力的因素探讨

介绍了阴极电泳涂装原理,讨论了溶剂含量、槽液的pH、槽液电导率、电泳时间、施工电压对阴极电泳泳透力的影响。     

用反渗透技术回收镀镍漂洗水

利用反渗透技术将镀镍漂洗水浓缩分离,浓缩液中ρ(Ni2+)达到20 g/L左右,浓缩液补加到镀镍槽中,透过液在镀镍漂洗槽中循环使用,实现了镀镍废水的零排放.向镀镍槽中加入硫酸钾,提高镀液的导电性能,同时降低镀液中氯化镍的质量浓度,使镀镍过程中阳极溶解速度和阴极沉积速度相接近.镀件在镀镍前和镀镍后都经过回收槽漂洗,使回收槽中镍离子的质量浓度保持不变.大约是镀镍槽中镍离子质量浓度的一半.采用这些措施后,可实现反渗透浓缩液的完全回收利用.     

NHD脱硫脱碳装置有关生产问题的分析和改造措施

阐述了ＮＨＤ溶剂脱硫脱碳机理、工业应用特征,对ＮＨＤ脱硫系统的溶液循环量、贫液Ｈ２Ｓ贫度的控制、ＮＨＤ溶液中水含量控制、低压闪蒸槽的定位、透平涡轮的改造问题进行了分析,并总结了改造措施。     

电泳槽液颜料絮凝的补救办法及对策

电泳槽液更新周期长，槽液老化严重，槽液高温、溶剂补给、过度超滤都影响槽液稳定性，使其容易产生絮凝。本文介绍了长更新周期电泳槽液因高温而导致颜料絮凝的补救办法，从理论上分析了各种颜料絮凝的原因及长更新周期电泳槽液管理对策。     

2,3-丁二醇萃取-精馏耦合工艺开发研究

在前期液-液相平衡研究的基础上,得出正丁醇、乙酸乙酯及乙酸丁酯在萃取2,3-丁二醇时的不同特点.并根据其特点,分别设计了2条创新的间歇-循环的萃取-精馏耦合工艺.根据乙酸乙酯、乙酸丁酯分配系数小、相比(质量比)要求较大的特点,设计萃取-精馏耦合工艺一(即溶剂循环、料液间歇进料),该工艺具有相比逐渐增大、溶剂循环萃取的特...     

金昌冶炼厂废水处理工艺探讨

探讨了石灰－硫酸亚铁－晶种循环处理含重金属离子废水的工艺流程,一段中和槽ｐＨ值控制国８Ｆｅ／Ａｓ值为１．５,二段氧化槽,ｐＨ值控制在９．３左右,Ｆｅ／Ａｓ值为２０,中和槽ｐＨ值控制在１１,晶种回流比为２０％－３０％,处理后的废水中重金属离子,砷,氟,悬浮物含量及ｐＨ值均低于固定排放标准。     

从硫铁矿矿渣中制备聚合硫酸铁

以硫铁矿矿渣为原料 ,按反浮选和选择性浸出原理除去杂质 ,在 1 0 0°C用硫酸浸得硫酸铁和硫酸亚铁混合液 ,并测定了 Fe2 + 和 Fe3 + 含量。同时对废铁屑经硫酸洗涤和纯碱洗涤后 ,把过量的废铁屑加入该混合液中 ,使整个溶液还原成硫酸亚铁溶液。采用氯酸钠氧化法 ,在 65°C经氧化、水解、聚合得聚合硫酸铁溶液 ,讨论了影响聚合反应的主要因素。对炼油厂废水进行处理 ,合成的聚合硫酸铁的处理效果明显优于市售三氯化铝     

Preparation of superhydrophobic silica‐based films by using polyethylene glycol and tetraethoxysilane

Preparation of superhydrophobic silica‐based films via sol‐gel process by adding polyethylene glycol (PEG4000) in the silica sol precursor solution has been developed. The casting films were prepared by casting the above solution on the glass and adding poor solvent on it or not. Surface roughness of the films was obtained by removing polymer from the films at high temperature. Then, the hydrophobic group on the surfaces was obtained by reaction with hexamethyldisilazane (HMDS). Characteristic properties of the as‐prepared surface of the films were analyzed by contact angle measurement, scanning electron microscopy (SEM), atomic force microscope (AFM), Fourier transform infrared (FT‐IR) spectrophotometer, and X‐ray photoelectron spectrometer (XPS). The results showed that the contact angles of the films were varied with the PEG weight fraction of the films, the solvent for the PEG solution, the reaction temperature and time, and adding poor solvent (n‐hexane) or not. However, the surface roughness has been controlled by adjusting the experimental parameters during the early period. The contact angle of the film that prepared by spraying the poor solvent (n‐hexane) onto each coating layer for four times after casting process was greater than 150°. It was difficult to obtain superhydrophobic surface without adding n‐hexane onto any coating layer in this system. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Effective control of α-olefin selectivity during Fischer–Tropsch synthesis over polyethylene-glycol enwrapped porous catalyst

Effective control of α-olefin selectivity during Fischer–Tropsch synthesis (FTS) was achieved through continuously adding a polar solvent, polyethylene glycol (PEG), in a fixed-bed reactor over an industrial Fe-based catalyst under typical FTS reaction conditions. The α-olefin content increased drastically and was independent of carbon number in C₆₊ range, whereas the product carbon-number-distribution changed unobviously. Similar trend was also observed in the results obtained from a continuously stirred tank reactor using PEG as reaction medium. This phenomenon can be explained by the suppressed α-olefin secondary reactions due to the existence of a PEG-membrane on the catalyst surface.     

化工厂洗桶难生化降解废水的处理对策

采用调节池+中和反应池+混凝沉淀池+水解酸化池+接触氧化池+二沉池+活性炭滤池+清水池的工艺方法处理化工厂洗桶难生化降解废水,经一年的运行结果表明,对多变的、难生化降解废水用此方法处理效果稳定,COD去除率达85%以上,水的色度、COD等指标能够稳定达到广东省现地方标准一级标准。     

饲料级磷酸氢钙市场预测和技术开发

回顾国内外饲料级磷酸氢钙市场,并对未来市场需求进行预测。在当前普遍采用的工艺、工程技术的基础之上,笔者结合多年的工程实践,设计出了一些新的装置和方案如生石灰消化和配乳,导流管式单槽单桨或特殊结构的单槽双桨磷酸反应槽,连续式脱氟(一段中和)反应槽,白磷肥分离装置等,同时还进行了经济效益分析。     

以二氯甲烷为溶剂对乙酰基二茂铁Mannich反应的研究

利用乙酰基二茂铁的活性α-H的性质进行了乙酰基二茂铁Mannich反应研究,先以磷酸为催化剂,醋酐为酰化剂合成了乙酰基二茂铁,然后探讨在二氯甲烷为溶剂的情况下,乙酰基二茂铁与二乙胺、甲醛的Mannich反应。考察了反应温度、物料摩尔比和反应时间及催化剂的用量对反应条件的影响,并通过红外、质谱对产物进行了表征。确定了以二氯甲烷为溶剂乙酰基二茂铁Mannich反应的合成工艺:乙酰基二茂铁、甲醛、二乙胺的摩尔比为1.0∶2.0∶3.0;操作方式为先加入二乙胺和甲醛,10 min后滴加体积分数为36%盐酸调解pH值在4—6之间,20min后滴加乙酰基二茂铁的二氯甲烷溶液,控制反应温度为50—52℃,反应7 h,产率为77%。     

pH-driven phase separation: Simple routes for fabricating porous TiO2 film with superhydrophilic and anti-fog properties

A series of TiO₂ surfaces with different pore sizes were easily fabricated via pH-driven phase separation in the sol–gel under template-free conditions. The approach is to obtain TiO₂ films with well-defined macropores by utilizing neutralization reaction from acid–base combination. The tuning of solution pH from neutralization could reduce the miscibility of solvent and solute and enable the formation of phase separation. The influence of preparation conditions (ratios of acid-to-base, aging time and solvents) on the pore formation was investigated. The porous TiO₂ films prepared through pH-driven phase separation exhibit promising super hydrophilic characteristic anti-fog property.     

2,2-二羟甲基庚醛的合成工艺研究

以甲醛和庚醛为原料,经羟醛缩合反应合成了2,2-二羟甲基庚醛(DMH)。羟醛缩合反应的最佳工艺条件为:反应温度35℃,n(甲醛)∶n(庚醛)∶n(NaOH)=4∶1∶1.3,缩合剂为10%NaOH溶液,反应时间为5h。加甲酸中和碱,经精制DMH的收率达到67.8%。DMH的结构用红外光谱(IR)表征。     

Chemical absorption of carbon dioxide into phenyl glycidyl ether solution containing THA-CP-MS41 catalyst

Carbon dioxide was absorbed into the phenyl glycidyl ether (PGE) solution within a range of 0–2.0 kmol/m³ in a stirred batch tank with a planar gas-liquid interface at 333–363 K and 101.3 kPa. Trihexylamine-immobilized on chloropropyl-functionalized MCM-41 (THA-CP-MS41) was used as a mesoporous catalyst, dispersed in organic liquid for the reaction between carbon dioxide and PGE. The measured absorption rates were analyzed to obtain the reaction kinetics of the consecutive chemical reactions which consisted of two steps using the mass transfer mechanism based on film theory. The overall reaction kinetics, analyzed with the pseudo-first-order reaction constant in the consecutive reaction model, was equivalent to the consecutive reaction kinetics. Effects of polar solvent, such as N, N-dimethylacetamide, N-methyl-2-pyrrolidinone, and dimethyl sulfoxide, on the reaction rate constants were observed using the solubility parameter of the solvent.