离子膜电解工艺操作与管理

分析了离子膜电解中各工艺控制指标对运行过程的影响 ,提出确保精制盐水杂质含量低 ,控制F -795膜的阴极碱液为 3 3 %～ 3 5 %、F - 893膜的阴极碱液为 3 2 %～ 3 3 .5 % ,阳极液质量浓度为 2 0 0～ 2 2 0g/L ,电解槽温度 ( 85± 3 )℃ ,以确保电解槽长期稳定运行     

CIM单元镍脂肪酸及其甲酯氢化催化剂的研制

在CIM - 6油脂氢化催化剂及其相关技术的基础上 ,研制成功CIM - 7脂肪酸氢化催化剂和CIM - 8脂肪酸甲酯氢化催化剂。又在相同条件下对十八碳烯酸加氢 ,同Pricat 9932 - 6(UnichemaInternational)、KE -FS40 (Sud -ChemicAg .)、G - 5 3 - 1(U .C .I.)催化剂对比 ,考察了CIM - 7的催化性能 ;当温度、压力、搅拌、时间相同 ,改变催化剂质量分数对不同酸值的棕榈油甲酯加氢 ,同SD - 2 5 0 (吉野Co .)催化剂对比 ,考察了CIM - 8的催化性能。结果表明 :(1)产品硬脂酸的碘值 (gI2 10 0g)分别为 0 76 (CIM - 7)、0 85 (Pricat9932 - 6 )、1.0 4(KE -FS40 )、1.2 8(G -5 3- 1) ,即催化活性和抗酸性CIM - 7>Pricat 9932 - 6 >KE -FS40 >G - 5 3 - 1。 (2 )当原料酸值为 1 1mgKOH g、w(催化剂 ) =0 2 0 %时 ,产品氢化棕榈油甲酯碘值 (gI2 10 0g)为 1 12 (CIM -8) ,2 4 0 7(SN - 2 5 0 ) ;当原料酸值为 0 0 3mgKOH g,w(催化剂 ) =0 0 76 %时 ,产品碘值为 1 90(CIM 8) ,12 18(SN - 2 5 0 ) ,即催化活性和抗酸性CIM - 8>>SN - 2 5 0。 3 产物中w(镍 ) =38 5×10 - 6 (CIM - 7) ,41 2× 10 - 6 (Pricat 9932 - 6 ) ,48 7× 10 - 6 (KE -SF40 ) ,5 7 4× 10 - 6 (G - 5 3- 1) ;1 18× 10 - 6 (CIM 8) ,1 83× 1     

导电涤纶的试制

用碘吸附 -铜离子络合工艺制得比电阻为 8× 10 3～ 1.5× 10 4 Ω· cm的导电涤纶 POY长丝。讨论了诸多因素对纤维比电阻的影响 ,通过实验选定了最佳工艺条件。碘吸附过程的最佳工艺条件为 :I/KI质量比 1.5～ 1.8,碘浓度 2 10 g/L,温度 70～ 80℃ ,时间 80 min;铜离子络合最佳工艺为 :Cu Cl/NH4 Cl质量比 0 .6 ,Cu Cl浓度 2 0～ 4 0 g/L,温度 85～ 95℃ ,时间 4 0 min     

用电化学法研制水杨醛

用阳离子交换膜 ,以Hg为阴极 ,Pb合金为阳极 ,由水杨酸电解还原研制水杨醛 ,实际产率达 80 %以上。由实验得出了电解合成的最佳条件 :14g水杨酸、2 5g亚硫酸氢钠、3 0g硼酸、2 7 5g氯化钾和 5 6g氢氧化钾共配制电解液 3 5 0mL ;电流密度 18A/dm2 ,电量 1 8F/mol,pH =6 0±0 2 ,电解反应的温度为 13～ 18℃ ,并采用分次投料方式。     

碘离子选择性电极测定海带、紫菜中碘及碘的浸出率

提出了用碘离子选择性电极测定海带、紫菜中碘的方法。在 0 .2 0 mol/L KNO3 ,1 .0× 1 0 -3mol/L Na2 SO3 ,p H 5 .0～ 6.0溶液中 ,碘离子浓度对数值在 5 .0× 1 0 -7～ 1 .0× 1 0 -1mol/L范围内与电位呈良好线性关系 ,检出限为 3× 1 0 -7mol/L,准确测定了海带、紫菜中碘的含量 ,对浸泡时间与海带中碘的浸出率关系进行了研究。回收率 95 %～ 98% ,相对标准偏差小于 2 .6%。     

联合法生产C1O2的几点体会

简要介绍了联合法ClO2 生产工艺 ,重点介绍了关于操作二氧化氯发生系统的几点体会 :控制NaCl、NaClO3 的质量浓度分别为 12 0± 5、4 5 0± 10 g/L ,盐酸质量分数为 (31± 0 .5 ) %且游离氯含量小于 1.0× 10 -5;吸收水量对产品二氧化氯溶液浓度的影响 ;控制发生器各室温度稳定 ;向发生器加酸要缓慢平稳 ;稳定各反应室加入的稀释空气量。另外还推测了二氧化氯发生器的构造     

自行设计安装的离子膜烧碱中试装置运行情况小结

一、概况我国早在1978年就由上海天原化工厂自己设计制造了中国第一台复极式离子膜电槽(0.5m~2×8室,年产100吨固碱),采用Nafion—227膜进行运转,生产300g/1的液碱。该装置在30A/dm~2时,单槽槽压为4～4.05V,电流效率83%,平均直流电耗     

一种新的全固态Zn（CN）4^2—电极用于镀锌液中锌的测定

本文报道了一种新的全固态Zn(CN)_4~(2-)离子电极的研制,以正交试验设计方法采用L_9(3~3)正交表试验优化电极性能。确定以十六烷基三丁基碘化铵(HTBA)为离子载体,膜含量5％,络合剂KCN浓度0.5mol/L时为最优因子组合。电极的平均斜率可达28.6mV/pc(20℃),线性范围1.0×10~(-1)～2.4×10~(-6)mol/L,检测下限4.0×10~(-7)mol/L。将电极用于各种镀锌液中Zn含量测定时,获得了良好的结果。     

S-940螯合树脂在二次盐水精制的使用情况

二次盐水质量是离子膜法电解生产能否高效、安全、稳定、长寿命运行的关键。目前 ,世界上只有 3家公司可以生产和提供工业化电解生产烧碱用膜 ,即美国杜邦公司、日本旭化成公司和旭硝子公司。无论哪家公司生产的离子膜 ,就膜本身而言 ,它们对二次盐水的质量要求大致相同 ,其中Ｃａ2 、Ｍｇ2 在 2× 1 0 - 8以下 ,最高也不能超过 3× 1 0 - 8;ＳＳ在 1 0 - 6 以下。氯碱工业用的原盐含有大量的Ｍｇ2 、Ｃａ2 、ＳＯ2 - 4等杂质 ,在食盐溶解过程中大量进入生产系统。在盐水精制过程中必须除去这些杂质。如果二次盐水Ｃａ2 、Ｍｇ2 含量…     

专利实例

电镀镍及其合金两则　2 0 0 35 0 1 无硼酸镀镍电解液一种无硼酸的镀镍电解液组成如下 :Ni SO4·6H2 O 2 0 0～ 360 g/L;Ni Cl2 · 6H2 O 30～ 90 g/L;Ni3 ( C6H5O7) 2 · 1 4H2 O2 4～ 42 g/L;C6H8O7· H2 O1 2～ 2 1 g/L;以水为溶剂。溶液的 p H值为 3～ 5。(日本专利 ) JP2 0 0 1 1 72 790 - A2 ( 2 0 0 1 - 0 6- 2 6)2 0 0 35 0 2 　　保护性 Ni- W合金镀层电解液提出了获得高耐蚀性 Ni- W合金镀层的方法和电解液。电解液组成和工艺条件如下 :硫酸镍 2 5～35 g/L;氯化镍 3～ 5 g/L;钨酸钠 8～ 5 0 g/L;柠檬酸钠 2 5～ 1 5…     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

Novel polyurethane coating technology through glycidyl carbamate chemistry

Glycidyl carbamate chemistry combines the excellent properties of polyurethanes with the crosslinking chemistry of epoxy resins. Glycidyl carbamate functional oligomers were synthesized by the reaction of polyfunctional isocyanate oligomers and glycidol. The oligomers were formulated into coatings with several amine functional crosslinkers at varying stoichiometric ratios and cured at different temperatures. Properties such as solvent resistance, hardness, and impact resistance were dependent on the composition and cure conditions. Most coatings had an excellent combination of properties. Studies were carried out to determine the kinetics of the curing reaction of the glycidyl carbamate functional oligomers with multifunctional and model amines. Detailed kinetic analysis of the curing reactions was also undertaken. The results indicated that the glycidyl carbamate functional group is more reactive than a glycidyl ether group. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, on October 27–29, 2004, in Chicago, IL.     

Highly moisture-proof polysilsesquioxane coating prepared via facile sol-gel process

A highly moisture-proof polysilsesquioxane coating was obtained from a new bis-silylated precursor, which was synthesized from 3-aminopropyltriethoxysilane (APTES) and m-xylylene diisocyanate (m-XDI) in tetrahydrofuran (THF) and verified by ¹H MAS NMR. For direct comparison purposes, an SiO₂ coating was also prepared by the Stöber method using tetraethoxysilane (TEOS) as the reactant. Interestingly, the coating obtained from the polysilsesquioxane sol exhibited a much higher moisture resistance capability than its counterpart, which was attributed to its more compact feature between nanoparticles as characterized by N₂ absorption experiment and transmission electron microscopy (TEM). Furthermore, its high transparency of about 92% showed potential for application in the protection of optical crystals.