The use of mathematical and computer models to explore the applicability of fluidized bed technology for highly exothermic catalytic reactions: II-oxidative dehydrogenation of ethylbenzene to styrene

✍ Scribed by S.S.E.H. Elnashaie; K.M. Wagialla; A.M. Helal

• Publisher: Elsevier Science
• Year: 1991
• Tongue: English
• Weight: 894 KB
• Volume: 15
• Category: Article
• ISSN: 0895-7177
• DOI: 10.1016/0895-7177(91)90032-3

✦ Synopsis

A model based on the two phase theory of fluidization is developed for the catalytic gasphase or&dative dehydrogenation of ethylbenzene to styrene in a fluidized bed reactor. The model takes into account the change in number of moles accompanying the reaction taking place in the dense phase. The system exhibited multiple steady states. An optimization search indicated that a maximum styrene production rate can be obtained at an oxygen/ethylbensene feed ratio of 0.39 and a dense phase temperature of 820 K. A parameteric sensitivity analysis, including a biication study, showed that this optimum steady state operation can be achieved by operating the reactor nonadiabatically with a feed temperature of 410 K and a catalyst particle diameter of 100 pm. Under these conditions the operating steady state would be an unstable one. NOMENCLATURE A, Aa, A, c PiI z Distance along bed height, m. &? Density of gas, 3. "ij Stoichiometric coefficient of compo-PP nent j in reaction i, dimensionless. Density of solid particle, 3. Emf Dense phase voidage at min-6 Bubble phase volume as a fraction imum fluidieation conditions, of total bed volume, dimensionless.

dimensioukas.