Improved Supported Metal Oxides for the Oxidative Dehydrogenation of Propane

CATEGORY: OXIDATIVE DEHYDROGENATION
Improved Supported Metal Oxides for the Oxidative Dehydrogenation of Propane

Type	Journal Article
Author	Joseph T. Grant
Author	Alyssa M. Love
URL	http://link.springer.com/article/10.1007/s11244-016-0671-2
Volume	59
Issue	17-18
Pages	1545-1553
Publication	Topics in Catalysis
Date	2016/07/29
Abstract	Oxidative dehydrogenation of propane (ODHP) is an attractive reaction for the on-purpose production of propylene. However, rapid consecutive over-oxidation of the desired olefin limits the selectivity, hampering industrial feasibility. Supported metal oxides, and in particular dispersed vanadium-containing materials, offer promising results. However, it is necessary to improve both the selectivity and activity (space–time–yield) to make this reaction attractive. Authors build on previous work that made it possible to increase the dispersion of group V metal oxides on silica using a sodium promoter. Using Raman spectroscopy and 51V MAS NMR, they postulate that the minor decrease in observed turnover frequency (TOF) for ODHP using sodium-promoted materials may be due to Na+ ions weakly interacting with the V=O site, responsible for the initial H-atom abstraction. While their observed TOF is well within the range of literature reported TOF for these materials, such a large deviation in reported TOF may be due to various impurities used in the silica of previously reported studies. Subsequently, they prepared a ternary metal oxide catalyst based on vanadium and tantalum exhibiting superior selectivity and productivity. Productivity of a combined V- and Ta-oxide catalyst supported on silica doubles the productivity of catalysts with low loadings of vanadium oxide supported on silica. The cause of the significant improvement are currently under investigation.

Techno-Economic Analysis of Oxidative Dehydrogenation Options

CATEGORY: OXIDATIVE DEHYDROGENATION
Techno-Economic Analysis of Oxidative Dehydrogenation Options

Type	Journal Article
Author	Gennaro J. Maffia
Author	Anne M. Gaffney
URL	http://link.springer.com/article/10.1007/s11244-016-0677-9
Volume	59
Issue	17-18
Pages	1573-1579
Publication	Topics in Catalysis
Date	2016/08/16
Abstract	The world-wide market for light olefins will approach one trillion pounds per year by the year 2020. Light olefins are conventionally produced by the steam cracking of hydrocarbons from ethane to gas oil. Decades old, the technology results in a range of by-products, some valuable, some with fuel value, and some requiring waste treatment before disposal. Authors report an economic analysis using a cost of production procedure commonly called a required netback analysis. They compared their results with the expected performance of a novel catalytic route with very high selectivity, running at much lower temperatures and similar pressures. The new route uses a mixed metal oxide catalyst in packed tubes with a heat transfer fluid in the reactor shell for heat management. Results suggest that the new route has much lower variable cost, fixed costs and capital recovery reaching shutdown economic level.

Oxidative dehydrogenation of ethane to ethylene over Ni–Nb–M–O catalysts: Effect of promoter metal and CO2-admixture on the performance

CATEGORY: OXIDATIVE DEHYDROGENATION
Oxidative dehydrogenation of ethane to ethylene over Ni–Nb–M–O catalysts: Effect of promoter metal and CO2-admixture on the performance

Type	Journal Article
Author	AiLing Qiao
Author	Venkata Narayana Kalevaru
URL	http://www.sciencedirect.com/science/article/pii/S0920586115005325
Series	Catalysis promoting the development of chemical industry: A special issue dedicated to Tianjin University’s 120th anniversary
Volume	264
Pages	144-151
Publication	Catalysis Today
Date	April 15, 2016
Abstract	Ni–Nb–O based catalysts have high activity and selectivity for the oxidative dehydrogenation of ethane (ODHE) to ethylene at relatively low temperatures. The parent Ni–Nb–O catalyst used in this work exhibited an ethylene yield of 32%. This solid was further modified by three promoters each, i.e. Cr, Mo, W, belonging to the same group of elements but exhibiting different d-characters. The purpose of such modification is to further improve activity and/or selectivity. However, the catalytic results of the doped solids revealed somewhat reduced activity compared to the parent Ni–Nb–O catalyst during ODHE. BET surface area data, reducibility, acidity characteristics as well as near-surface composition of Ni–Nb–M–O showed considerable deviations. However, these depend upon the nature of promoter doped. The near-surface region Ni/Nb ratio is the key parameter for tuning the catalytic properties of the solids. Among the three modifiers used, Cr displayed relatively superior catalytic performance compared to other two yielding in an ethane conversion of 26% and an ethylene selectivity of ca. 65%. Even so, the introduction of CO2-admixture into the reactant feed mixture improved the selectivity of ethylene in ODHE. Ni–Nb–Cr–O solid in particular revealed an enhanced ethylene selectivity of ca. 85% at slightly reduced ethane conversion.