Zeolites as catalysts for organic transformations uses of ZSM

The high catalytic activity of zeolites arises from the Brpnsted acidity of A1 sites, represented in resonance pair 25.32. The Si Al ratio affects the number of such sites and acid strength of the zeolite. 

Zeolite catalysts are important in the catalytic cracking of heavy petroleum distillates. Their high selectivities and high 

Recent advances have shown zeolites are effective in catalysing the direct conversion of synthesis gas to motor fuels. The MTO (methanol-to-olefins) process converts MeOH to C2-C4 alkenes and is also catalysed by ZSM-5. The development of a gallium-modilied ZSM-5 catalyst (Ga-ZSM-5) has provided an efficient catalyst for the production of aromatic compounds from mixmres of C3 and C4 alkanes (commonly labelled LPG). 

Zeolites are replacing acid catalysts in a number of manufacturing processes. One of the most important is the alkylation of aromatics. The Mobil-Badger process for producing CgHsEt from CgHg and C2H4 provides the 

What are the similarities and differences between the structures of a feldspar mineral and a zeolite  

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The declining oil reserves have stimulated considerable efforts towards the exploration of alternative sources of energy and organic chemicals. One solution is to use the abundant supply of coal as a source of synthesis gas (CO + H2) which is readily converted to methanol (MeOH). MeOH can then be transformed into higher molecular weight hydrocarbons (olefins, aliphatics and aromatics) over shape-selective zeolite catalysts, the most successful of which in this respect is H-ZSM-5, capable of converting MeOH to hydrocarbons up to Cio- The selective synthesis of ethylene and propylene, the key intermediates for the production of detergents, plasticizers, lubricants and a variety of chemicals, proceeds over smaller pore zeolites such as chabazite and erionite. 

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