Alkylation of ethylbenzene with methanol over X type zeolites

The methylation of ethylbenzene over X type zeolites was studied at atmospheric pressure and temperature of 400–500 °C. Ring and side-chain alkylation take place, respectively, on the acid and base zeolite, viz. HX and KX. With KX at 500 °C, alkylation and dealkylation proceed, respectively, via carbanion and carbonium ion mechanism, whereas dehydrogenation and demethylation occur via free radical mechanism. The ratio of radical to ionic activity increases with increasing contact time, reaction temperature and time-on-stream.     

Catalytic process modeling and sensitivity analysis of alkylation of benzene with ethanol over MIL-101(Fe) and MIL-88(Fe)

A solvothermal method was used to synthesize MIL-101(Fe) and MIL-88(Fe), which were used for alkylation of benzene. The synthesized catalysts were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscope, dynamic light scattering, and BET techniques. Metal-organic frameworks (MOFs) were modeled to investigate the catalytic performance and existence of mass transfer limitations. Calculated effectiveness factors revealed absence of internal and external mass transfer. Sensitivity analysis revealed best operating conditions over MIL-101 at 120°C and 5 bar and over MIL-88 at 142°C and 9 bar.     

乙苯与乙醇在β沸石催化剂上的烷基化反应

考察了乙苯与乙醇在β沸石催化剂上的烷基化反应、乙苯自身的歧化反应,以及反应温度、物料料配比及质量空速对烷基化反应的影响.获得了在β沸石催化剂上乙苯与乙醇合成二乙苯的烷基化反应的适宜工艺条件.结果表明:在温度200～220℃;乙苯与乙醇物质的量之比为4～6;乙苯质量空速2～4的工艺条件下乙醇的利用率大于85%,烷基化选择性大于70%.     

二氧化碳气氛下改性SiO2负载V催化乙苯脱氢

以三嵌段共聚物P123为模板剂,正硅酸乙酯为硅源,采用水热法和浸渍法制备改性SiO2负载钒V/ZrO2-TiO2-SiO2催化剂.在CO2气氛下考察其催化乙苯脱氢的反应性能,并采用X射线衍射、BET比表面积、扫描电镜等技术对催化剂体相及表面性质进行表征.结果表明：催化剂在600℃、乙苯空速（LHSV）0.44 h-1、n（CO2）/n（EB）=5.4的条件下具有较好的催化活性,ZrO2和TiO2在SiO2负载型催化剂表面有相互修饰的作用.改性ZrO2-TiO2-SiO2载体有助于提高V2O5在载体表面的分散程度,抑制VOx的聚合,减小V2O5的微晶尺寸,提高其氧化还原能力.     

基于改进粒子群算法的乙苯脱氢过程多目标优化

设计了一种基于支配关系构造非支配解集的多目标粒子群算法(MOPSO),将当前找到的非支配解保存到一个外部集——最优解集,利用支配更新其最优解集,多次迭代后得到Pareto最优解集。把乙苯脱氢反应过程的收率和选择性作为优化目标,动力学模型和实际生产状况作为约束条件构造乙苯脱氢过程的多目标优化问题,利用改进的多目标粒子群算法进行优化求解。基于求得的Pareto最优解集研究了各个操作条件对乙苯脱氢生产过程收率和选择性的影响,为后续乙苯催化脱氢系统实施先进控制奠定了基础。     

第三代催化干气制乙苯装置设计

介绍了抚顺石化公司60 kt/a催化干气制乙苯装置的设计特点,比较了各种工艺方案.生产实践表明:该装置的主要工艺设计方案先进合理,主要工艺指标基本达到设计要求,为第三代催化干气制乙苯技术的工业应用奠定了基础.     

苯乙烯生产最新技术

乙苯脱氢技术是苯乙烯的主要生产方法。简要介绍了3种主要的乙苯生产工艺:气相法烷基化工艺、液相法烷基化工艺、稀乙烯原料制乙苯工艺的工艺特点、原理及国内外研究进展。在此基础上,对苯乙烯生产技术,如绝热负压脱氢技术、苯乙烯与环氧丙烷联产工艺的研究状况和主要技术指标进行了论述,并指出了苯乙烯生产技术的发展方向。     

Amorphous porous MxTi mixed oxides as catalysts for the oxidative dehydrogenation of ethylbenzene

The properties of different metal‐oxide‐doped porous titanium oxides as catalysts for the oxidative dehydrogenation of ethylbenzene were investigated. Amorphous porous mixed oxides based on the amorphous titania matrix with selected metal ion centers as active sites have been prepared by an acid‐catalyzed sol–gel method. The dehydrogenation of ethylbenzene was studied in a continuous gas phase flow reactor under different reaction temperatures at ambient pressure. Among the 23 catalysts studied the amorphous porous AM‐Cr₅Ti mixed oxide is the most promising catalyst. At 350 °C a 75% selectivity to styrene at a 29% conversion of ethylbenzene was obtained. BET, HRTEM, XRD, GC, MS, TGA and optical microscopy were employed to characterize the fresh and used AM‐Cr₅Ti catalyst. This revised version was published online in August 2006 with corrections to the Cover Date.     

乙苯装置反烷基化反应末期操作工况的优化

针对乙苯装置反烷基化反应末期多乙苯转化率下降 ,需要对反烷基化反应末期的操作工况优化 ,通过实验得出了优化的操作工况为 :反应温度 441～ 445℃ ,苯进料量 162 0～ 1810 m3/h,多乙苯进料中乙苯摩尔分数 1% ,反应压力 60 0 k Pa,可使多乙苯转化率大于等于 5 0 % ,延长催化剂的运行寿命 ,能耗小 ,选择性高     

高收率乙苯脱氢催化剂GS-12的工艺条件研究

介绍了高收率乙苯脱氢催化剂GS-12的特性,研究了乙苯脱氢反应温度、水蒸汽与乙苯物质的量比、空速与转化率和选择性的关系,确定了乙苯脱氢催化剂GS-12在实际生产中适宜的工艺条件.工业应用表明,GS-12催化剂活性较高,能够适应较低水蒸汽与乙苯物质的量比,机械强度高,抗粉化性能好,床层阻力降小,使用寿命预期在30个月以上,综合性能达到国际先进水平.