Abstract: This invention provides a catalytic epoxidation of styrene to styrene oxide with molecular oxygen using cobalt containing zeolite. Catalytic epoxidation of styrene-to-styrene epoxide was carried out using molecular oxygen in presence of Co2+ exchanged zeolites. Molecular oxygen from air is also useful for the epoxidation reaction at atmospheric pressure. The presence of adsorbed water molecules in the catalyst also increases the styrene conversion without affecting the styrene oxide selectivity. Various alkali and alkaline earth cationic promoters were introduced into the zeolite catalyst to increase the styrene oxide selectivity. The present invention explore the effect of adsorbed water molecules and alkali and alkaline earth metal cationic promoters in the cobalt exchanged zeolite catalyst, on the styrene conversion and styrene oxide selectivity for the catalytic epoxidation of styrene to styrene oxide with molecular oxygen.
Type:
Grant
Filed:
March 14, 2006
Date of Patent:
March 18, 2008
Assignee:
Central Salt and Marine Chemicals Research Institute
Abstract: A new eco-friendly process is described in the present invention for the preparation of bromobenzene through substitution of one of the C—H proton of benzene ring with a highly reactive hypobromous acid generated in situ, said process comprises the steps of activating a water soluble, easy to handle, brominating reagent with a mineral acid at elevated temperature and atmospheric pressure to generate active bromine species which in turn reacts with benzene.
Type:
Grant
Filed:
December 17, 2003
Date of Patent:
October 18, 2005
Assignee:
Central Salt and Marine Chemicals Research Institute