离子膜法电解系统加酸探讨

探讨了阳极液加酸的作用、脱氯塔加酸量及电解槽加酸的控制和需注意的事项。     

浅谈离子膜电槽加酸的调节

本文介绍了离子膜电槽进槽盐水加酸的原理，以及酸度不足对运行带来的影响和加酸过量对电解槽及离子膜造成的危害分析，总结出电槽加酸的必要性，并探讨控制加酸量维持PH值稳定的方法，延长离子膜的使用寿命。     

离子膜电解槽加酸探讨

采用向离子膜电解槽阳极液中加盐酸的方法可以提高阳极电流效率,同时可以降低氯中含氧和阳极液氯酸盐含量。以蓝星北化机厂家NBH-2.7型自然循环离子膜电解槽为例,阐述了阳极液加酸的作用、加酸点、加酸量控制和应注意的问题。     

影响1,4-丁二醇加酸色度原因探讨

针对1,4-丁二醇(BDO)加酸色度偏高的问题,我们详细研究BDO中的金属和有机杂质对加酸色度的影响。通过实验发现1,4-丁烯二醇含量对加酸色度有明显的影响,其他杂质则影响较小。该研究结果将有助于控制BDO产品质量,也为BDO产品质量指标的修订提供参考。     

高浓度印钞凹印废水处理的实验研究

对高浓度印钞凹印废水进行了一系列的非加酸工艺的处理试验。结果表明,完全可以采用非加酸工艺达到理想的处理效果。当投加S-1018系列处理剂后,出水pH控制在6～7,CODCr控制在<2000mg/L的范围内,为该废水治理达标排放奠定了基础。     

如何提高糠醛的产量

通过控制加酸的量及改造锅炉来提高糠醛的产量。     

加酸运行提高循环水浓缩倍数的研究

分析了乌石化公司几套循环水系统及补水现状,提出加酸运行能有效提高循环水浓缩倍数并简述加酸运行的必备条件。计算饱和指数从理论上进行分析,同时从静态和动态试验进行验证。动模试验结果证实平行的两组试验,加入同样药剂,分别控制pH值为8.0～8.5和8.4～8.9,粘附速率分别是0.27mg/(cm·2d),和0.42mg/(cm·2d),说明加酸能有效地减少结垢。     

循环水加酸改善水质工艺

汽轮机凝汽器循环冷却水消耗水量大,采用循环水加酸改善水质工艺,在增大循环水的浓缩倍率(由2．6上升至3．3)的同时,控制加酸后循环水的pH值,电厂新鲜水补水量由200t／h降低到160t／h,阻垢剂的用量也相应减少,经济效益良好。     

输卤回水长管道化学清洗排气技术

介绍了输卤回水长管道的化学清洗的一种排气技术。该技术首先进行理论计算,根据计算值通过加酸量控制排气量,加酸方式为一次流过、不循环的清洗方式,解决了管道清洗中气阻和爆管问题,实现了化学清洗的平稳进行,收到了良好的效果。     

新旧离子膜混装时的加酸控制

通过理论计算和实际操作,说明新旧离子膜混装时如何控制加酸量更有利用安全运行。     

2-丙烯酰胺基-2-甲基丙磺酸合成工艺的新进展

2-丙烯酰胺基-2-甲基丙磺酸（AMPS）的合成方法主要有异丁烯法、异丁醇法、羟基磺酸法、异丁烯磺酸法等,对比反应条件,气相异丁烯法是最温和的,适宜工业化生产。目前异丁烯法已成为主流。为提高产品质量,应从反应下手,改进AMPS的生产工艺。主要改进方法有：合成重结晶一步法、添加试剂法、连续法等。合成重结晶一步法将缩短生产周期,提高生产效率;添加试剂将改善反应性能,提高反应质量;连续法生产AMPS投资少,产品稳定,将成为合成AMPS的趋势。     

对甲苯磺酰氨基脲的合成工艺研究

以甲苯、氯磺酸、水合肼、氰酸盐等为原料 ,通过三步反应合成聚丙烯用高效发泡剂对甲苯磺酰氨基脲。研究表明 ,加入一定量的铵盐可提高制备对甲基苯磺酰氯中间体的反应温度 ,从而使其收率增加 ;用四氢呋喃做溶剂比用苯做溶剂可以得到较高产率的对甲基苯磺酰肼中间体 ;反应温度对终产物的收率影响较大。     

低游离酚热塑性酚醛树脂的合成

改变传统合成工艺,在热塑性酚醛树脂合成过程中加入1种有机酸A,得到低游离酚酚醛树脂。考察了酚、醛物质的量比,有机酸A用量对树脂软化点的影响以及反应温度、反应时间对树脂中游离酚含量的影响。确定了最佳合成工艺条件:第1步反应温度98~104℃,反应时间1 h,催化剂盐酸用量1.0%(基于苯酚质量),苯酚、甲醛和有机酸A的物质的量比为1∶0.82∶0.02;第2步反应温度180℃,反应时间1.5 h。通过气相色谱分析游离酚质量分数由原来的5%~10%降到0.55%。     

高品质环氧大豆油的研制

文章采用732#强酸性阳离子交换树脂为催化剂,改进型无溶剂法合成高品质环氧大豆油。实验确定了高品质环氧大豆油的最佳合成条件:采用逐步加料,按m(大豆油):m(88%甲酸):m(30%双氧水):m(催化剂)=1:0.35:1.2:0.15的比例加料,加0.5 mL 1%的EDTA稳定剂,制得的环氧大豆油品质较高。     

2-丙烯酰胺-2-甲基丙磺酸合成中试研究

介绍了以丙烯腈、发烟硫酸、异丁烯为原料,一步反应生产2-丙烯酰胺-2-甲基丙磺酸（AMPS）的中试研究.该工艺主要由合成、精制、溶剂回收三个单元组成,其中原料投料摩尔比为丙烯腈∶发烟硫酸∶异丁烯=7∶1∶1,加酸反应温度10℃,时间3h;通入异丁烯反应温度40 ℃,时间2.5 h.粗产品收率不低于90％,精制收率不低于65％,精制后可得质量分数大于99％的AMPS产品.     

The electrochemical reduction of Sn(II) at the dropping mercury electrode from aqueous 1 M sulfuric acid and from 0.3 M phenolsulphonic acid and its inhibition by ensa-6

By means of the demodulation technique for the first time the high reduction rate constant of the Sn(II) ion in sulfuric acid is obtained. From the value of the operational transfer coefficient it follows that a following, potential independent “chemical” step is rate determining. On the addition of an inhibitor at positive potentials the transfer of the first electron can be made slow because this process is inhibited much more strongly than the following chemical step. At high concentration of the inhibitor the first electron transfer is rate determining at all potentials. In phenolsulphonic acid as the base electrolyte it appears that an intermediate chemical step is rate controlling together with the following chemical step. The intermediate step could be made rate determining by adding a little of the inhibitor. With a high concentraton of the inhibitor the first electron transfer becomes rate controlling again. Also the reduction of Sn(II) from a practical plating bath is discussed.     

CONSECUTIVE ESTERIFICATION OF 1,4-BUTANEDIOL WITH ACRYLIC ACID BY HOMOGENEOUS CATALYSIS

The esterification of 1,4-butanediol with acrylic acid catalyzed by sulfuric acid in the absence of solvent was studied in a batch stirred reactor. Experiments were carried out with different acid/ alcohol mole ratios and different amounts of sulfuric acid in the temperature range 70 to 90°C and 1 atm. It was found that the esterification of 1.4-butanediol with acrylic acid is a two-step consecutive, reversible reaction and each esterification step follows a first-order rate expression with respect to each component. A kinetic model was proposed to describe such a consecutive, reversible esterification reaction catalyzed by sulfuric acid. The equilibrium constants were determined from the equilibrium concentrations of each component while the rate constants in each reaction step were calculated by correlating the experimental data with the developed kinetic model.     

Effect of operating parameters on precipitation for recovery of lactic acid from calcium lactate fermentation broth

Precipitation is a simple, efficient method for separating and recovering lactic acid in the form of calcium lactate from fermentation broth by adding sulfuric acid. Major operating parameters of the recovery step as well as the temperature of concentration of the recovered lactic acid solution and the type and amount of adsorbent used for pigment (color) removal were optimized. When the molar ratio of calcium lactate to sulfuric acid was 1: 1 and the pH was increased to a value greater than the pKa (3.86), calcium sulfate was precipitated and could be removed more effectively, allowing for more efficient separation and recovery of supernatant lactic acid. Precipitation could be facilitated by adding calcium lactate solution with mixing (up to 220 rpm) and was completed in over 18 h. The optimal temperature for the concentration of lactic acid recovered from the supernatant after removing the precipitated calcium sulfate was found to be 90 °C in terms of the time required for concentration and the stability of the product. Activated carbon (SX-PLUS, 9 g/L) was most effective as an adsorbent for color removal from the recovered lactic acid. Under the optimized precipitation conditions, an overall yield of 92% of lactic acid from fermentation broth could be achieved.     

酸性氯化钾镀锌故障分析

在对某铁件制品进行酸性氯化钾镀锌过程中,镀层出现低位发雾,而且有白斑,在硝酸出光及钝化后依然存在。运用鱼骨分析法、排除法等方法分析发现,该故障产生原因是由于镀件在防锈水中浸泡时形成的一层氧化膜的缘故。针对此问题,经过反复实验,对原工艺流程进行了改进,增加了一道98%浓硫酸浸泡(3～10s)工序,从而避免了该故障的发生。     

2,6-二甲基3,5-二氯-4-羟基吡啶合成工艺研究

以脱氢醋酸为原料经两步反应合成 2 ,6 二甲基 3,5 二氯 4 羟基吡啶 ,第一步是 2 ,6 二甲基 4 羟基吡啶的制备 ,第二步是 2 ,6 二甲基 4 羟基吡啶的氯化反应。对于 2 ,6 二甲基 4 羟基吡啶的制备 ,投料比为n (脱氢醋酸 )∶n (氨 ) =1∶2 ,反应溶剂的体积组成为V(N ,N 二甲基甲酰胺 )∶ V(反应中蒸出液 )∶ V(前次反应抽滤母液 ) =1∶1∶2 5 ,投料的顺序为先将脱氢醋酸溶于溶剂中 ,再加氨水 ,而不能先加氨水后加溶剂。氯代反应制备 2 ,6 二甲基 3,5 二氯 4 羟基吡啶 ,2 ,6 二甲基 4 羟基吡啶水溶液的质量浓度为 0 0 5g/mL ,操作顺序为通氯气一定时间后 ,先调节反应液pH到 3,然后将固体滤出。