Methanol to olefin catalysis

J.F. (2004) Theoretical smdy of the methylbenzane side-chain hydrocarbon pool mechanism in methanol to olefin catalysis. /. Am. Chem. Soc., 126, 2991-3001. 

Methylbenzene chemistry on zeolite h-beta multiple insights into methanol-to-olefin catalysis. /. Phys. Chem. B, 106, 2294-2303. 

HSAPO-34 during methanol-to-olefin catalysis ex situ characterization after cryogenic grinding. Catal. Lett., 76, 89-94. 

Haw, J.F. and Marcus, D. (2005) Well-defined (supra) molecular structures in zeolite methanol-to-olefin catalysis. Top. Catal, 34, 41 8. 

J. F., Nicholas, J.B., Heneghan, C., Methybenzenes Are the Organic Reaction Centers for Methanol-to-Olefin Catalysis on HSAPO-34, p. 10725-10727, Copyright 2000 American Chemical Society... 

D. Lesthaeghe, V. van Speybroeck, G. B. Marin, M. Waroquier, The rise and fall of direct mechanisms in methanol-to-olefin catalysis an overview of theoretical contributions, Ind. Eng. Chem. Res., 2007, 46, 8832-8838. 

Song WG, Fu H, Haws JF SupramolecrJar origins of product selectivity for methanol-to-olefin catalysis on HSAPO-34, J Am Chem Soe 123 4749-4754, 2001. 

Most of the commercial zeolite catalyzed processes occur either through acid catalysis fluid catalytic cracking (FCC), aromatic alkylation, methanol to olefins (MTO),... 

Most of the catalytic interest in the AlP04-based molecular sieves have centered on the SAPOs which have weak to moderate Bronsted acidity, and two have been commerciahzed SAPO-11 in lube oil dewaxing by Ghevron and SAPO-34 in methanol-to-olefins conversion by UOP/Norsk Hydro. Spurred on by the success of TS-1 in oxidation catalysis, there is renewed interest in Ti, Co, V, Mn and Cr substituted AlP04-based materials, for a review of recent developments in the AlP04-based molecular sieves see [35]. 

Lewis, J.M.O. (1988) Methanol to olefins process using silicoalumino-phosphate molecular sieve catalysts, in Catalysis 1987 (ed. J.W. Ward), Elsevier, Amsterdam, p. 199. 

Other modifications of zeolites can be achieved with, reagents which react with OH groups. The silanation of various mordenites is the only process to be studied in detail. ZSM-5 treated with dimethyl silane has been described as a catalyst for the conversion of methanol to olefins. The use of various other reagents (P, B, and Sb compounds) with ZSM-5 and related zeolites has also been described. The effects observed in catalysis are broadly similar... 

J. Marchi at Ryksuniversiteit Gent (Belgium) provide a comprehensive review of zeolite catalysis for the methanol-to-olefin reaction. He examines small, medium, and large-pore zeolites, the important role of acidity and shape selectivity on product distribution, and, like several of the other Reporters, the importance of understanding the coke-forming deactivation processes. 

The capabilities of zeolites are largely limited by the almost exclusive use of SiO AlO tetrahedral building blocks (aluminophosphate and other structures have not yet found large-scale application in catalysis, except for SAPO-34 used for methanol to olefins conversion). The 3D framework of zeolites is microporous with channels or voids of up to 1.0 nm in size. It is for this reason that the field of catalytic applications of zeolites is limited to small organic molecules (usually not larger than o-xylene). In contrast, MOFs contain bulky organic components and can be formed from an infinite set of building blocks, which make it possible to finely tune their porous properties. 

Iron has played an extremely important role in catalysis in the past, present and increasingly will in the future. The fundamental work carried out over a centuiy ago continues to he relevant and informative to modern catalysis. The discovery and development of heterogeneous iron-hased catalysts used in large-scale ammonia, methanol and hydrocarbon synthesis, amongst others, has undoubtedly sculpted modern science and society. Most crucial to the use of iron in modem catalysis is perhaps the excellent sustainability traits associated with iron. The high natural abundance, low cost and low toxicity of iron oxides and iron salts provides sustainable avenues for molecule diversification. In particular, the ability of simple iron oxides and iron salts to facilitate crosscoupling and olefin hydrofunctionalisation reactions, where noble metals are commonly required, demonstrates a significant advance towards more sustainable synthesis. 

Mole s reaction path for olefin formation via toluene. Adapted from Mole T, Bett G, Seddon D. Conversion of methanol to hydrocarbons overZSM-5 zeolite an examination of the role of aromatic hydrocarbons using IScarbon- and deuterium-labeled feeds.] Catal 1983 84 435—45 Mole T, WhitesideJA, Seddon D. Aromatic co-catalysis of methanol conversion over zeolite catalysts.] Catal 1983 82 261-6. 

Polymer-supported catalysts incorporating organometaUic complexes also behave in much the same way as their soluble analogues (28). Extensive research has been done in attempts to develop supported rhodium complex catalysts for olefin hydroformylation and methanol carbonylation, but the effort has not been commercially successful. The difficulty is that the polymer-supported catalysts are not sufftciendy stable the valuable metal is continuously leached into the product stream (28). Consequendy, the soHd catalysts fail to eliminate the problems of corrosion and catalyst recovery and recycle that are characteristic of solution catalysis. 

As in the hydroformylation of olefins, isomerization (of excess epoxide) occurs, producing ketones (23). Since the catalysis by dicobalt octacarbonyl is promoted by methanol, which is known to cause disproportionation,... 

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