【作者】 马占伟；

【导师】 郭洪臣；

【作者基本信息】 大连理工大学 ， 工业催化， 2011， 硕士

【摘要】 在小型固定床反应装置上对DRF型催化剂进行了苯与乙醇气相烷基化制乙苯反应性能的研究,研究了工艺条件、镧和磷改性等因素对主要副产物二甲苯的生成影响。基于性能评价和特征表征相结合的方式,对DRF型催化剂和工业参比催化剂进行了稳定性对比考察,同时对两种催化剂催化性能差异的原因及其再生后的催化性能进行了探讨。得到了以下主要结果：(1)DRF型催化剂对苯与乙醇气相烷基化合成乙苯具有良好的乙苯选择性、稳定性以及较低的二甲苯相对含量。乙苯合成适宜的反应条件为：温度360-400℃,苯醇摩尔比在5-7,苯醇混合质量空速为12 h-1左右；(2)适当降低反应温度及提高苯醇摩尔比可抑制副产物二甲苯的生成。提高原料中苯醇摩尔比,有利于提高乙苯选择性并降低副产物二乙苯的选择性；在相对较大的质量空速下操作,缩短了反应物的停留时间,降低了催化剂的结焦程度,减少了二甲苯的生成几率；(3)La和P改性后DRF催化剂的总酸量较未改性前高,但产物中杂质二甲苯的含量未降低,乙苯选择性有所提高,二乙苯相对含量降低；(4)在2000 h的长周期寿命考察中,在相同反应条件下,DRF型催化剂上二甲苯的相对含量低于参比催化剂,乙苯选择性也优于参比催化剂,其综合催化性能超过了参比催化剂的水平,DRF型催化剂是一种具有良好工业应用前景的催化剂。更多还原

【Abstract】 Vapor-phase alkylation of benzene with ethanol was investigated in a small fixed-bed reactor over DRF catalyst. The influence of process conditions and catalyst modification was studied on the formation of main byproduct xylene. The paralleled stability test of DRF and referential catalysts was carried out and the catalystic performance differences among these catalysts were also investigated combining the catalytic reaction experiments and the characterization of the catalysts, and the performance of regeneration for two catalysts were studied via coke-burning regeneration methods. The results can be concluded as follow:(1) DRF catalyst has the good ethylbenzene selectivity, stability and the relative low content of xylene to the benzene alkylation with ethanol to form ethylbenzene. The results shows that the appropriate operating conditions are as follows:temperature,360～400℃; benzene/ethanol molar ratio,5～7; the weight hourly space velocity of benzene and ethanol, 12.(2) The decrease of reaction temperature and increase feed ratio can restrain the formation of xylene. The enhance of feed ratio of benzene to ethanol is beneficial to increase the ethylbenzene selectivity and reduce the diethylbenzene selectivity. Under the relatively big weight hourly space velocity, the retention time of the reactant is shortened, the coked degree of the catalyst is reduced and the probability of xylene generation is decreased.(3) The total acid quantity of modified DRF catalyst is larger than before, but the relative content of xylene is not reduced. Besides, the ethylbenzene selectivity is improved and the relative content of diethylbenzene is reduced over the modified catalyst.(4) The relative content of xylene is lower and selectivity of ethylbenzene is higher over DRF catalyst than referential catalyst in reaction for 2000 hours under the same conditions. The comprehensive performance has exceeded the level of referential catalyst. The results indicat that the DRF catalyst has good prospect of industrial application.更多还原