Butenes dehydrogenation

The spent C4 streams from either process can be sent to isobutylene extraction, butene dehydrogenation, or used in further refinery processing. 

The constraint of thermodynamic equilibrium for the butene dehydrogenation reaction is effectively removed since hydrogen is converted to water by oxidation. Equilibrium yields then approach 100% over the complete temperature and partial pressure range of interest. 

The Behavior of Titania-Supported Iron Oxide Catalysts in Butene Dehydrogenation... 

A schematic of a palladium membrane reactor is shown in figure 1. The reversible reaction of 1-butene dehydrogenation occurs on the reaction side of the membrane in which the chrome-alumina catalyst is uniformly packed. The oxidation of hydrogen with oxygen in air occurs in the permeation or separation side on the palladium membrane surface. The... 

Figure 4 Arrhenius Plot of the Observed Reaction Rate of 1-butene Dehydrogenation...

The feasibility of the palladium membrane system with an oxidation reaction on the permeation side and 1-butene dehydrogenation reaction on the reaction side in a membrane reactor has been successfully demonstrated. The palladium and its alloy membrane not only can withstand high temperature but also are selectively permeable to hydrogen... 

PF/PF Adiabatic isothermal Tube side 1-butene dehydrogenation (tul side) oxidation of H2 (shell side) Itoh Sl Govind, 1989b... 

For a comparison with known commercial processes used for increasing the yield of butadiene, it is enough to indicate that the removal of 90% of the hydrogen formed in the course of butene dehydrogenation at 800 K and atmospheric pressure is equivalent to... 

I-Butene dehydrogenation coupled with hydrogen oxidation/ dense Pd membrane... 

Butene dehydrogenation into butadiene on chromia-alumina A- Empirical deactivation functions ... 

Fig 13. Evolution of the coke profile in an adiabatic reactor for butene dehydrogenation [Ref 331 ... 

Fig 14 Flow of butadiene at the exit of an adiabatic reactor for butene dehydrogenation versus time [Ref. 33]. 

Sheikh, J. Kershenbaum, L.S. Alpay, E. 1-Butene dehydrogenation in rapid pressure swing reaction processes. Chem. Eng. Sci. 2001, 56, 1511. 

A somewhat different application of perovskites is the oxidative dehydrogenation of olefins. Kehl et al. (202) reported that Lao.8Cro.65Feo.55Ch can be used for butene dehydrogenation to butadiene and also for the conversion of other monoolefins containing at least four C atoms, such as the production of isoprene from isoamylenes. 

Often an important reason to avoid intraparticle diffusion resistances is from selectivity considerations. To maximize the intermediate product in a consecutive reaction scheme, we should avoid intraparticle diffusional resistances. For butene dehydrogenation it can be seen in Fig. 14 that... 

All NiO catalysts used here showed the phenomenon of wildness described by Reilly (16). This state of the catalyst is characterized by a sharp drop in bed temperature, a large increase in product gas, and considerable laydown of carbon. The selectivity of butene dehydrogenation to butadiene falls effectively to zero. Several experiments were performed in an attempt to find the cause of wildness. There can be little doubt that this condition is due to reduction of nickel oxide to nickel metal, and it is the latter which disrupts the carbon-carbon bonds. X-ray analysis of a wild NiO catalyst showed the presence of approximately 50% metallic nickel, and reduction would probably go to completion if the reactor did not choke with carbon. 

Li may be estimated as at least a factor of 5 for butene dehydrogenation and about 15 for butadiene decomposition. 

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