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What are zeolites ? What is their utility ? |
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Answer» Solution :The catalytic reaction that DEPENDS upon the pore structure of the catalyst and the size of the reactants and PRODUCTS is called shape-selective catalysis. Zeolites are good shape-selective catalysts because of their honeycomb-like structures. They are microporous aluminousilicateswith three dimensional networks of silicates in which some SILICON atoms are REPLACED by aluminium atoms giving Al-O-Si framework. The reactions taking place in zeolites depend upon the size and shape of reactants and products as well as upon the PORES and cavities of the zeolites. Utility : Zeolites are widely used as catalysts in petrochemical industries for cracking and isomerisation of hydrocarbons. An important zeolite catalyst used in petrochemical industry is ZSM-5. It converts alcohols directly into gasoline (petrol) by dehydrating them to give a mixture of hydrocarbons. |
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