摘要
采用COMSOL Multiphysics软件对规整及散堆固定床反应器内的乙苯脱氢反应进行了模拟计算,对比了等温和绝热条件下2种反应器的性能,研究了反应器串联段数、工艺条件、催化剂结构对绝热规整反应器内乙苯脱氢反应性能的影响。结果表明:等温和绝热条件下,与颗粒散堆固定床相比,规整反应器的乙苯转化率更高、苯乙烯选择性更高、反应器压降更小。进料温度为893 K、压力为104 k Pa时,绝热规整反应器中乙苯转化率为54.81%,苯乙烯选择性为94.84%,而绝热散堆固定床仅为39.55%和92.52%。对于绝热规整反应器,三段工艺的乙苯转化率和苯乙烯收率比一段或二段工艺高;升高温度、降低压力可以提高乙苯转化率,且较低的温度和压力可得到较高的苯乙烯选择性;减小催化剂孔壁厚度可以得到更高的乙苯转化率和苯乙烯选择性,适宜孔壁厚度为0.2 mm;催化剂孔密度对反应性能几乎没影响。
Ethyl-benzene dehydrogenation process in monolithic and randomly packed reactors was simulated by COMSOL Multiphysics, and the reactor performances were compared under isothermal and adiabatic conditions. The influence of stage number, process conditions and catalyst structural parameters on the performance of adiabatic monolithic reactor was also investigated. The results indicate that higher ethyl-benzene conversion and styrene selectivity as well as lower pressure drop can be obtained in monolithic reactor compared with randomly packed reactors under both isothermal and adiabatic conditions. The ethyl-benzene conversion is 54.81% and the styrene selectivity is 94.84% at 893 K and 104 kPa in the monolithic reactor, while they are 39.55% and 92.52% of the random one, respectively. For adiabatic monolithic reactor, a three-stage reactor can achieve higher ethyl-benzene conversion and higher styrene yield than a one- or two-stage reactor. The conversion of ethyl-benzene increases with the increase of temperature and the decrease of pressure, and lower temperature and pressure are favorable for higher styrene selectivity. Reducing catalyst wall thickness realizes higher ethyl-benzene conversion and styrene selectivity, and an appropriate thickness is 0.2 mm. The cell density of catalyst has little impact on the reactor performance.
出处
《化学工程》
CAS
CSCD
北大核心
2017年第6期55-61,共7页
Chemical Engineering(China)
关键词
乙苯脱氢
苯乙烯
规整反应器
规整催化剂
模拟
ethyl-benzene dehydrogenation
styrene
monolithic reactor
monolithic catalyst
simulation
