Dehydrogenation of Alkanes

Abstract

The sections in this article are Introduction Importance of Light Alkenes Historical Developments Conceptual Approach Influence of Temperature on the Equilibrium Influence of Partial Pressure on the Equilibrium Energy of Alkane Dehydrogenation Formation of By‐Products Removal of Hydrogen to Shift the Equilibrium Spatial Separation of Dehydrogenation and Hydrogen Combustion Dehydrogenation and Hydrogen Combustion in a Catalyst Bed Oxidative Dehydrogenation ( ODH ) Catalytic Systems Supported Chromia Catalysts Chromia on Al 2 O 3 Supports A Structure and Reactivity B Oxidized State C Reduced State D Regeneration Chromia on Si O 2 / Zr O 2 Supports Supported Platinum/Tin Catalysts Platinum as Active Component Tin as Modifier State and Mode of Operation of Platinum and Tin A State of Pt and Sn B Mode of Operation of Pt and Sn C Ensemble Effect D Ligand Effect Role of the Support Regeneration of Supported Platinum/Tin Catalysts A Treatment with Molecular Oxygen B Treatment with Chlorine C Treatment with Hydrogen Kinetics and Mechanism Kinetics of Dehydrogenation Chromia/Alumina Catalysts A Mechanism 1 B Mechanism 2 Platinum and Platinum/Tin Catalysts Kinetics of Deactivation Reactor Concepts Endothermic Character Preheating the Feed and Carrying out the Reaction in an Adiabatic Reaction System Carrying Out the Reaction in a Heated Reactor Preheating the Catalyst and Carrying Out the Reaction in an Adiabatic Reactor Regeneration Continuous Systems Discontinuous Systems Commercial Processes UOP Oleflex Process U hde STAR Process ABB Lummus CATOFIN Process Linde PDH Process S namprogetti‐ Y arsintez FBD Process Dehydrogenation of Other Alkanes Dehydrogenation of Heavy n ‐Alkanes Dehydrogenation of Cyclohexane Future Developments Membrane Technology CO 2 as a Diluent Conclusions and Future Prospects

Conversion of Y into SSZ-13 zeolites and ethylene-to-propylene reactions over the obtained SSZ-13 zeolites

“…The SSZ-13s prepared by MW heating were analyzed for aluminum content (or SAR), porosity, Al coordination, and acidity by ICP, nitrogen adsorption, 27 Al NMR, and NH 3 -TPD, respectively. As shown in Table 2, the SAR values confirmed the wide range of Al contents in the SSZ-13s and the introduction of additional Si (because of the higher SAR values of the SSZ-13s compared with used Y) in the conversion of Y into the SSZ-13 zeolites.…”

“…To meet increasing demand, propylene has been produced by several new strategies, such as propane dehydrogenation and the metathesis of ethylene and 2-butene [27,28]. However, the propylene supply may fail to satisfy the demand in the near future (if there is no conversion of ethylene into propylene) due to the rapidly increasing ethylene supply from ethane cracker and shale gas.…”

“…(a) Nitrogen adsorption isotherms, (b)27 Al NMR spectra and (c) ammonia TPD patterns of SSZ-13 zeolites prepared with MW (Left and right-hand desorption signals correspond to the weak and strong acid sites, respectively).…”

Effect of VOx Species and Support on Coke Formation and Catalyst Stability in Nonoxidative Propane Dehydrogenation

“…The existing industrial DH processes employ catalysts based on chromium oxide or metallicp latinum. [2,4] Supported VO x -containing catalysts were extensively studied for their activity and selectivity in the conversion of C 3 -C 4 hydrocarbonsi nto corresponding olefins in the absence of gas-phase O 2 .Fromamechanistic viewpoint, this reactioncan run oxidatively or nonoxidatively with participation of lattice oxygen of oxidized VO x species [5][6][7][8][9][10][11][12][13][14] or their reduced counterparts, [15,16] respectively.A lthought he former approachi st hermodynamically not limited, it suffers from low on-stream stability caused by ar educed capacity of VO x speciest op rovide their activeo xygen. Recently, VO x /SiO 2 -Al 2 O 3 catalysts were shown to have commercially attractive activity, propylene selectivity and durability in propane DH.…”

“…It is industrially produced as ac o-product of steam cracking of naphtha and fluid catalytic cracking of heavy oil fractions. [1,2] Metathesis of ethylene with 2-butenes [3] and nonoxidative dehydrogenation (DH) of propane [2] are two commerciallya vailableo n-purpose propylene production alternatives. Growing extraction of shale gas drives the price of propaned own thus making the latter process more commercially attractive despite high energy demandc aused by strong endothermicity of the reaction.…”