Modelling of butene‐1 dehydrogenation in a fixed bed reactor — bed and pellet profiles

Abstract

A homogeneous model incorporating the Dumez & Froment kinetics has been proposed for the butene‐1 dehydrogenation reaction over a commercial chromia‐alumina catalyst. The model predicts bed and pellet concentration and temperature profiles. While the temperature profiles obtained suggest a temperature minimum in the reactor, the pellet remains nearly isothermal. Under the condition used in this study, a series type of coke deposition is obtained. A comparison between experimental results obtained using the neutron attenuation technique and theoretical coke profiles reveals excellent agreement and confirms the validity of the model and the kinetics employed.

Catalyst sintering in fixed‐bed reactors: Deactivation rate and thermal history

“…It can be observed that the pattern of coke deposition along the bed changed when the temperature was increased. Fluctuations in the coke dep- osition profile that can be observed in curve 1 are thought to be due to temperature inhomogeneities that appear under reaction conditions, as pointed out by Dumez and Froment (1976) and by Acharya and Hughes (1990). A slow-moving, lowtemperature wave during the dehydrogenation of 1-butene was also observed during the course of this work.…”

MTG Process in a Fixed-Bed Reactor. Operation and Simulation of a Pseudoadiabatic Experimental Unit

“…19,20 Other authors have usedLangmuir-Hinshelwood-Hougen-Watson(LHHW) kinetic models for the main reaction and for the deactivation. [21][22][23] At the same time, experimental techniques have been described in the literature for verification of the profiles calculated for the temperature and for coke deposition along the reactor. [24][25][26][27] In processes on acid catalysts, such as the MTG process, knowledge of the evolution with the time on stream of the temperature profile along the reactor is very important because the acid sites are very sensitive to temperature.…”

Regeneration of Coked Catalysts: The Effect of Aging upon the Characteristics of the Coke Deposits

“…The optimization of the operation of a chromia-alumina catalytic reactor coked during 1-butene dehydrogenation has been carried out by Dumez and Froment (1976) and by Borio et al (1992). Other authors have also simulated the production/ deactivation stage (Acharya and Hughes, 1990) and the regeneration stage (Acharya et al, 1992) for this system, although the optimization of the cycle was not attempted in this case.…”