均苯四酸二酐的生产和应用

介绍了均苯四酸二酐的性质,生产概况,制备和应用情况。     

溶胶-凝胶法制备催化剂的研究进展

溶胶 凝胶技术越来越广泛应用于催化剂制备过程,介绍了溶胶-凝胶法的机理、分类以及在催化剂制备中的应用与特点,分析归纳了溶胶 凝胶法制备催化剂过程中金属前驱体、水解、干燥方法和焙烧温度等因素对制得高分散、高比表面积和良好孔径的催化剂的影响。在制备催化剂的过程中,要合理调节和控制这些因素,才能制备高分散性、高纯度和高活性的催化剂。最新研究结果表明,用溶胶 凝胶法制得的催化剂组分更分散,改善晶格氧活性,对异丁烷转化率和氧化产物的选择性均有所改善。     

国内外偏酐,均酐生产现状及进展

介绍了国内外偏苯三酸酐,均苯四酸二酐的生产现状,生产工艺,发展趋势,原料来源及在精细化工产品中的应用,并且分析了偏苯三酸酐产品的经济效益。     

非酸性催化剂催化合成均苯四酸四辛酯研究

以均苯四甲酸二酐（或酸）与2-乙基己醇在非酸性催化剂存在下进行酯化反应,合成了均苯四酸四（2-乙基己）酯增塑剂（统称均苯四酸四辛酯增塑剂）。研究了催化剂用量、投料配比、反应温度及时间对均酐（酸）转化率的影响,确定了最佳工艺条件,转化率可达99．8％。对酯化动力学进行了初步研究,并建立了300吨／年生产装置。采用非酸性催化剂进行酯化反应,取消了中和、水洗工序,降低了原料消耗,减少了废水,回收醇的质量也得到改善。     

溶胶-凝胶法制备纳米尺度催化剂的研究进展

介绍了溶胶-凝胶法制备纳米尺度催化剂的基本过程和其最新研究进展。指出:将溶胶-凝胶法与其他技术相结合,从而提高纳米催化剂的稳定性,将是溶胶-凝胶法在纳米催化剂制备中的发展方向。     

均苯甲酸二酐的生产和应用

介绍了均苯二甲酸二酐的性质,生产方法及应用情况。     

Ce-Mo-Ti-V催化制备苯四甲酸二酐

开发了一种由均四甲苯空气气相氧化制均苯四甲酸二酐过程所需的催化剂,该催化剂活性组分为Ce-Mo-Ti-V。通过实验研究了载体种类、活性组分、温度、空速和反应物浓度对工艺结果的影响。实验表明：在空速6 000 h^－1,温度为455℃,均四甲苯浓度为20 g/m³时,均苯四甲酸二酐的质量收率达到101.7%。     

气相氧化法生产均苯四甲酸二酐催化剂进展

介绍了均四甲苯空气气相氧化制均苯四甲酸二酐氧化过程所需催化剂的进展,着重介绍了催化剂活性组分和制备方法在国内外的研究和应用情况,井展望了未来的研究方向.     

精均苯四甲酸二酐的研制

开发了一种由均四甲苯空气气相氧化制备均苯四甲酸二酐过程所需的催化剂,该催化剂活性组分为V-Ti-P-Nb。研究了载体种类、活性组分、温度、空速和反应物浓度对工艺结果的影响。同时研究了将粗酐直接利用有机溶剂进行重结晶精制的方法。     

均苯四甲酸二酐生产中废料的回收利用

本文介绍了均苯四甲酸二酐的用途和生产过程,同时重点介绍了生产中废料的回收利用。     

Fire safety of thermoplastic polyurethane based on pyromellitic dianhydride

In this paper, pyromellitic dianhydride (PMDA) was firstly used as fire safety agent for thermoplastic polyurethane (TPU). And, the fire safety improvement of PMDA in TPU was intensively investigated by limiting oxygen index (LOI), smoke density test (SDT), cone calorimeter test, and thermogravimetric/infrared spectroscopy, respectively. It has been found that PMDA could significantly improve the ignition level, and the LOI value increase to 28.5% when 8.0 wt% PMDA was incorporated into TPU; PMDA also could effectively suppress the smoke production and heat release during the combustion process. The peak heat release rate and total smoke release of the sample with 8.0 wt% PMDA were decreased by 68% and 22% compared with pure TPU in cone calorimeter test. The thermogravimetric/infrared spectroscopy results showed that PMDA could improve the thermal stability of TPU composites at high temperature and increased the release of CO₂, H₂O, and so on. All results confirmed that PMDA would have a good prospect in reducing the fire hazard of TPU.     

Fenton试剂预处理高浓度均苯四甲酸二酐生产废水的研究

研究采用Fenton试剂预处理含高浓度均苯四甲酸二酐生产废水。以废水的COD去除率为指标,通过单因素试验和正交试验,对Fenton试剂催化氧化有机物的影响因素进行分析。结果表明:在反应初始pH值为3.0、H2O2用量为35mmol/L、Fe2+用量为4.0mmol/L、反应时间为60min的条件下,COD的去除率达到76%。同时,处理后废水的BOD5与COD的质量比由0.140提高到0.417,可生化性显著提高,有利于后续的生化处理。     

均四甲苯的制备及应用

综述了均四甲苯的制备工艺、反应机理、分离提纯方法以及以均四甲苯为原料制备均苯四甲酸二酐(PMDA)的方法。     

Curing and thermal behaviour of epoxy resin in the presence of pyromellitic dianhydride and imidazole

The curing behaviour of DGEBA was investigated by differential scanning calorimetry in the presence of varying amounts of PMDA. The molar ratio of DGEBA : PMDA was varied as 1 : 0.8, 1 : 1, 1 : 1.5, 1 : 2.0, and 1 : 2.5. The heat of polymerization (ΔH) was found to be maximum at a molar ratio of 1 : 0.8 (DGEBA : PMDA). To study the effect of imidazole content on the curing behaviour, varying amounts of imidazole, i.e., 0.1, 0.15, 0.2, and 0.3% (w/w) were used keeping the ratio of DGEBA : PMDA (1 : 0.8) constant. A broad exotherm was observed in all the samples. A significant decrease in the peak exotherm was observed when 0.1% imidazole was used. Further increase in the imidazole concentration up to 0.2% resulted in a marginal decrease in the peak exotherm temperature. Thermal stability of epoxy resin, cured isothermally, was evaluated by recording thermogravimetric traces in nitrogen atmosphere. The percent char yield was highest in case of resin sample, IP1‐30 (i.e., DGEBA (1 mole) cured using 0.8 mole of PMDA in the presence of 0.3 (w/w) of imidazole). © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

共沉淀法制备铜钴基低碳混合醇催化剂

采用分步连续共沉淀法制备系列K改性的铜钴基催化剂,并对催化剂催化活性进行考察。结果表明,在钴铜质量比1∶1、K_2CO_3质量分数1%、pH=7.2和反应温度310℃条件下,催化剂催化活性最佳,CO转化率65.74%,液相产物中C_(2+)OH产量0.062 g·(m L·h)-1,C_(2+)OH质量分数18.95%。     

V2O5基多元催化剂的表面酸性与均四甲苯催化氧化选择性和活性的关系

以均四甲苯气相催化氧化制备均苯四甲酸二酐为研究对象,通过测定催化剂表面酸性,研究了以V2O5为基础,加入其它金属氧化物的多元组分催化剂的表面酸性与氧化选择性和活性的关系;同时研究了催化剂的组成、V2O5还原度和焙烧温度对其酸性的影响。结果表明,催化剂的表面酸性与氧化选择性和活性有关,V2O5-TiO2-Na2O-P2O5是酸性催化剂;对于催化剂V2O5-TiO2-Na2O-P2O5来说,当V^5 /Vtotal的值接近54．3％时,催化剂的表面酸性最高,当此催化剂在温度为550℃下焙烧,所得催化剂的酸度有一最大值。