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气相三氧化硫磺化甲苯制备对甲苯磺酸——温度对磺化反应的影响 总被引:3,自引:1,他引:2
气相三氧化硫磺化甲苯制备对甲苯磺酸——温度对磺化反应的影响刘邦孚吴金川张德立汪宝和谈道(天津大学石油化工技术开发中心,天津300072)关键词:甲苯三氧化硫磺化对甲苯磺酸1前言对甲苯磺酸是制备对甲酚的重要中间体,目前工业上主要是采用浓硫酸磺化甲苯来生... 相似文献
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气相磺化法研制对甲苯磺酸 总被引:2,自引:0,他引:2
采用新型的实验室制取方法——气相磺化法(即共沸去水磺化法)研制对甲苯磺酸。用过量的甲苯蒸汽直接磺化,经脱色、结晶、抽滤而制得。产品为白色晶体.含量大于90%,游离酸小于4%,收率能达到50%~60%。文中给出了制备条件、操作方法和产品特性数据。 相似文献
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本文论述了合成对甲苯磺酸的四种方法,分别采用硫酸、三氧化硫、氯磺酸等三种不同的磺化剂,并对这四种方法进行了比较,认为采用三氧化硫磺化法生产对甲苯磺酸具有一定的优势。同时简述了对甲苯磺酸的精制和分析方法。 相似文献
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以具有快速强放热特性的甲苯液相SO3磺化为目标反应,利用微反应器热、质传递能力强的优点,以提高反应性能和过程可控性。针对微反应器内的甲苯液相SO3磺化工艺进行了研究,考察了反应温度、SO3质量分数、SO3与甲苯物质的量之比、空速(LHSV)、产物放置时间、溶剂极性和母液循环次数对产物选择性的影响。结果表明,在温度为28℃、LHSV为13 000 h-1、1,2-二氯乙烷为溶剂的条件下,通过母液多次循环,磺酸异构体产物中对甲苯磺酸的选择性高达96.54%,间甲苯磺酸选择性则降低至0.33%。 相似文献
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一、前言生产苯酚目前还采用磺化碱熔法。苯经磺化生成苯磺酸,再转变为钠盐后进行碱熔生成苯酚钠,然后酸化得粗苯酚,经真空蒸馏得工业品苯酚。由于酸化过程是采用二氧化硫,因而在粗苯酚中带入了部分的亚硫酸氢钠,如果不进行中和,则在蒸镏过程中亚硫酸氢钠分解出的二氧化硫进入成品中,使成品容易变质而带色,影响产品质量。因此蒸馏前,必须用纯碱中和粗苯酚,使成弱碱性(pH=8)。过去,采用把纯碱与水配成浆状悬浮液直接加入蒸馏锅中与苯酚中和。去年,我们进行了改进,把粗苯酚在锅外中和成碱性(pH=8),再经过充分的澄清后进行蒸馏。这样,不但增加了产量,而且保证了质量和降低了原料消耗。 相似文献
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用精密转动氧弹燃烧热量计和衬铂氧弹测量了含一定结晶水的对甲基苯磺酸样品的固态燃烧焓值,用两种方法估算了无水对甲基苯磺酸(TSA)的固态生成焓值。其平均值和总误差为500±24kJ/mo 相似文献
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微波辐射对甲苯磺酸催化合成乙酸环己酯 总被引:15,自引:0,他引:15
以冰醋酸和环己醇为原料 ,环已烷为带水剂 ,对甲苯磺酸作催化剂 ,采用微波辐射技术 ,在常压下直接合成乙酸环己酯。最适宜反应条件为 :n(环己醇 )∶n(乙酸 ) =1 5∶1 0 ,对甲苯磺酸用量 0 2 0 g ,带水剂用量 5mL ,微波功率 5 95W ,辐射时间 15min ,产率达 97%以上 相似文献
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1-(并二甲硫基)甲基-4-甲氧基苯的合成 总被引:2,自引:0,他引:2
0.15mol茴香醛和0.6mol甲硫醇在9mmol对甲苯磺酸催化下发生反应,合成了相应的缩硫醛,产率83.7%。通过红外光谱、元素分析、核磁共振检测对产物结构进行了确证。此外,浓硫酸、氯化锌也是反应的催化剂。 相似文献
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糠醛异丙硫醇缩醛的合成研究 总被引:2,自引:0,他引:2
在15mmol对甲苯磺酸催化下,01mol糠醛和24ml异丙硫醇反应得到了糠醛异丙硫醇缩醛,产率748%。并通过IR、1HNMR对产物结构进行了确证。 相似文献
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A polyaniline (PANI) was synthesized by the oxidative polymerization using ammonium persulfate as an oxidizing agent. The PANI was then stirred with excess fuming sulfuric acid at room temperature for 6 h to obtain water soluble sulfonated polyaniline (SPANI). The degree of sulfonation was found to be 93–94% from the Fourier transform infrared (FTIR) and elemental analysis. The solubility of the SPANI in water was 1.25 g/L at room temperature and appeared as a green color solution. Conductivity of the PANI was decreased after sulfonation. A proliferation of hydrophilic nature of the PANI after sulfonation was observed from the water contact angle measurement. From the UV analysis, it was revealed that the energies required for the π–π* and bipolaron/polaron transitions are less and the intensity of these transitions are lower in SPANI compared to those of PANI. A detailed study on the crystal structures of PANI and SPANI were accomplished from the powder X‐ray diffraction analysis. The SPANI exhibited a more ordered structure having a higher degree of crystallinity and crystallite sizes with an increased unit cell volume compared to the PANI. After sulfonation the morphology of PANI was transformed from a rod‐like shape to a flat‐plate shape. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
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Opal hydrogels were prepared by sulfonation of dry polystyrene (PS) colloidal crystals with sulfuric acid, in which the introduced sulfonic acid and sulfone groups were responsible for the hydrophilic and crosslinked performances, respectively. The sulfonation occurred inwardly from the latex particles surface forming a hydrogel layer, whose thickness increased with temperature and modification time. The chemical compositions, water uptake and morphologies of the hydrogels were characterized. An application of the hydrogels as templates was demonstrated to prepare structured silica by a sol‐gel process. 相似文献
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茴香醛和惜内硫醇在对甲苯磺酸催化下发生反应,合成阿相应的缩硫醛,产率达84.9%。通过红外光谱、核磁共振检测,对产物结构进行了确证。 相似文献
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α-呋喃甲酸烷基酯类香料的合成 总被引:7,自引:0,他引:7
以0.01mol对甲苯磺酸和5ml30%过氧化氢作催化剂,在苯或甲苯中01molα 呋喃甲酸和05~012mol脂肪醇回流反应3h,以80%~956%的收率合成了7个糠酸烷基酯。结果表明酯的收率普遍提高。 相似文献
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Roberto Sanz Alberto Martínez Delia Miguel JuliaM. lvarez‐Gutirrez Flix Rodríguez 《Advanced Synthesis \u0026amp; Catalysis》2006,348(14):1841-1845
Simple Brønsted acids such as p‐toluenesulfonic acid monohydrate (PTS) or polymer‐bound p‐toluenesulfonic acid efficiently catalyze the direct nucleophilic substitution of the hydroxy group of allylic and benzylic alcohols with a large variety of carbon‐ and heteroatom‐centered nucleophiles. Reaction conditions are mild, the process is conducted under an atmosphere of air without the need for dried solvents, and water is the only side product of the reaction. 相似文献