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以间甲基苯酚为基本原料,经过亚硝化、氧化反应合成了3-甲基-4-硝基苯酚,研究了一步氧化法合成的工艺参数,最终得到了一步氧化法合成3-甲基-4-硝基苯酚的较佳工艺条件。小试实验结果表明:在最佳工艺条件下,3-甲基-4-硝基苯酚的合成收率达到97%。 相似文献
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《精细化工原料及中间体》2019,(3)
<正>本发明涉及一种由二氧化碳和苯酚一步合成水杨酸苯酯的方法,属于水杨酸苯酯合成技术领域。该方法以二氧化碳和苯酚为原料,在一定的二氧化碳压力和温度下,采用催化剂、助剂,直接催化合成水杨酸苯酯。本发明以二氧化碳、苯酚为原料一步催化合成水杨酸苯酯,其工艺路线简单,原料易得,成本低廉,避免了腐蚀性强和毒性大的原料及催化剂的使用;以二氧化碳作为反应物,实现二氧化碳化学利 相似文献
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以苯甲醇、苯酚为起始原料,利用相转移催化法经5步反应合成一种二苯美仑类化合物:4-(邻苄氧基)-N-乙基丁胺盐酸盐,反应总收率68.8%。反应过程中采用了优化的工艺技术,通过提高催化剂活性Al2O3的用量,结果使中间体2-苄基苯酚收率超过文献值8%。整个合成具有原料价廉易得、反应条件温和等特点。 相似文献
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《塑料制造》2006,(10):51-51
日本Daicel化工公司与大阪的关西大学应用化学系合作开发了一种丛苯和一氧化碳出发一步合成苯酚的工艺路线。以往提出的一些直接法苯酚生产技术,例如苯和氢气及氧气在钯催化的膜式反应器中反应的工艺,都因收率太低(低于15%)而难以实现工业应用。而在目前常用的工业生产苯酚路线中,一般需要三个步骤来产出苯酚。首先,苯与丙烯反应而生成异丙苯;然后异丙苯氧化生成过氧化氢异丙苯,再分解得到苯酚和联产物丙酮。而在这种新工艺中,苯在有空气(0.5~1MPa分压)存在的环境中与其还原剂作用的一氧化碳(0.5-1MPa分压)反应而直接合成苯酚。反应可以在醋酸水溶液中于90度的温度下进行,采用一种非均相催化体系如磷酸钼钒。在实验室条件下,已经取得了25%~30%的单程转化率和90%的苯酚选择性。催化剂可以使用5次以上,然后则必须进行更换。 相似文献
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D.P. Ivanov V.I. Sobolev L.V. Pirutko G.I. Panov 《Advanced Synthesis \u0026amp; Catalysis》2002,344(9):986-995
The synthesis of dihydroxybenzenes (DHB) via the gas‐phase oxidation of phenol with nitrous oxide in the presence of benzene was studied. Addition of benzene to the feed mixture greatly improves the selectivity and catalytic stability of the Fe‐containing ZSM‐5 zeolite, that was previously considered to be a main obstacle to the development of a new process. Reaction conditions strongly affect the distribution of the DHB isomers: the ratio of hydroquinone to catechol may vary from 1.4 to 10, with the resorcinol fraction being nearly constant and comprising 3–5%. Some 40 h experiments on the oxidation of a phenol‐benzene mixture demonstrated the high efficiency of the formed FeZSM‐5 catalyst. With a good stability, the catalyst provides 97% phenol selectivity referred to DHB and 85–90% N2O selectivity referred to the sum of DHBs and phenol. A new process for hydroquinone and catechol synthesis based on the neat oxidation of benzene with recycling of the phenol as an intermediate product is suggested. 相似文献
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催化苯直接羟基化是开发绿色苯酚生产新技术的高原子经济性的挑战性课题,但该工艺存在芳香C-H键难活化、产物酚的选择性较低等问题,其中高效催化剂的研制是核心问题之一。根据含铁催化剂独特的化学结构和催化性能,本文从配合物均相催化剂、仿生催化剂、负载型非均相催化剂等方面综述了含铁催化剂催化苯直接羟基化制备苯酚的研究进展,并着重介绍了Fenton体系和仿生催化体系的反应机理。分析表明,以氧化物及天然矿物作为载体的含铁催化剂合成简单,活性高,有较大的研究及工业开发价值。此外,研究催化机理对设计合成高效苯羟基化的催化剂具有指导意义。 相似文献
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Nonionic organic contaminants such as phenol, benzene, and toluene from contaminated wastewater on laboratory scale can be effectively sorbed by cellulosic wood pulp sheet incorporated with three polar functional groups. The synthesis was carried out by graft copolymerization reaction of N,N‐dimethylaminoethylmethacrylate with methacrylic acid onto wood pulp. The preparation conditions at which the grafting process proceeds homogeneously are determined. Characterization and some selected properties of the original and grafted wood pulp were evaluated using FTIR and scanning electron microscope, also, the removal of phenol, benzene, and toluene on laboratory scale was investigated by using gas chromatography. It was found that phenol shows the highest removal percent than that of benzene and toluene. The efficiency of removal of the nonionic contaminants is found to be 97%, which shows a great promise for its applicability in the removal of organic contaminates from wastewater. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3589–3595, 2006 相似文献
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环己基苯经过氧化反应可生产苯酚和环己酮,还可以用作锂离子电池电解液的添加剂,也可用作柴油的十六烷值调和组分,是一种高附加值、有市场潜力的精细化学品。本文介绍了国内外通过苯与环己烯烷基化合成环己基苯及所用催化剂的研究进展,总结了苯加氢烷基化反应机理和反应路径的研究成果,包括加氢烷基化活性的来源、中间产物和碳正离子中间体的推断以及各反应产物的形成。通过对加氢烷基化机理的认识,回顾了加氢烷基化催化剂的设计思路和发展历程。最后指出可开发用于苯与环己烯烷基化的B酸型、B-L酸型以及固载化离子液体等新型催化剂。提出可借助最新的碳正离子研究手段对加氢烷基化机理进行补充完善,并认为可利用多级孔沸石作为加氢烷基化催化剂的酸性载体。 相似文献
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DFT calculations have been achieved to obtain a convincing model for the active structure in a Re cluster/HZSM-5 catalyst active for direct phenol synthesis from benzene and molecular oxygen. Re10 clusters with interstitial N atoms composed of two Re octahedra edge-shared with each other were concluded as a stable active structure in agreement with the EXAFS analysis. The adsorption and behavior of benzene, oxygen atom and molecule and phenol on the Re cluster were examined to obtain the energy diagram for the phenol synthesis including intermediate and transition states, which explains the reaction steps for the phenol synthesis. 相似文献
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间三氟甲基苯酚是医药和农药化工中的重要中间体。三氟甲苯经过硝化、氢化还原、重氮化水解得到产品。本文在前人的工作基础上对三氟甲基苯酚的合成工艺进行了优化改进,提高了收率和纯度,并对反应的优化过程给出了解释。 相似文献
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The direct synthesis of phenol from benzene in the gas phase was studied over hydroxyapatite catalysts. The reaction was carried out in a fixed-bed reactor at atmospheric pressure and reaction temperature of 450°C in the presence of ammonia. A high selectivity (about 97%) of phenol formation at about 3.5% conversion of benzene was achieved over catalysts containing Ca and Cu ions in the cation part of hydroxyapatite. Besides phenol as the main reaction product, aniline is also formed. The reaction mechanism involves formation of N2O from NH3 in the first step of reaction. Benzene is oxidized by active oxygen species which are formed on the catalyst by decomposition of N2O. 相似文献