What is dehydrogenation of ethylbenzene?
Introduction. The dehydrogenation of ethylbenzene over potassium-promoted iron oxide catalysts is a reversible endothermic reaction which is performed at around 900 K in excess of steam yielding styrene and the main by-products benzene and toluene [1].
How do you make styrene from ethylbenzene?
The conventional method of producing styrene involves the alkylation of benzene with ethylene to produce ethylbenzene, followed by dehydrogenation of ethylbenzene to styrene. Styrene undergoes polymerization by all the common methods used in plastics technology to produce a wide variety of polymers and copolymers.
How do you make ethylbenzene?
Ethylbenzene is produced by the catalytic alkylation of benzene with ethylene, or from mixed xylenes by isomer separation and catalytic isomerisation, or from 1,3-butadiene in a two-step process where the butadiene is converted to vinylcyclohexane which is then dehydrogenated.
What is produced by dehydrogenating ethylbenzene?
Abstract. The dehydrogenation of ethylbenzene to styrene is a highly important industrial reaction and the focus of significant research in order to optimise the selectivity to styrene and minimise catalyst deactivation.
Is dehydrogenation exothermic or endothermic?
Dehydrogenation processes are used extensively to produce aromatics in the petrochemical industry. Such processes are highly endothermic and require temperatures of 500 °C and above. Dehydrogenation also converts saturated fats to unsaturated fats.
How is styrene obtained?
Almost all styrene is now produced by dehydrogenation of ethylbenzene, a compound obtained by reacting ethylene and benzene—both of which in turn are derived from petroleum. More than half of the styrene produced is made into polystyrene, a light, stiff plastic widely used in injection-molded or foamed articles.
What is a dehydrogenation reaction?
Dehydrogenation is the process by which hydrogen is removed from an organic compound to form a new chemical (e.g., to convert saturated into unsaturated compounds). It is used to produce aldehydes and ketones by the dehydrogenation of alcohols.
What is ethylbenzene used for?
It is naturally found in coal tar and petroleum and is also found in manufactured products such as inks, pesticides, and paints. Ethylbenzene is used primarily to make another chemical, styrene. Other uses include as a solvent, in fuels, and to make other chemicals.
What is produced by dehydrogenating ethylbenzene over zinc oxide catalyst?
Dehydrogenation of ethylbenzene to styrene in the presence of CO 2 was investigated over a series of catalysts prepared by calcination of hydrotalcite-like compounds. The Mg/Zn/Al/Fe catalyst affords the highest ethylbenzene conversion of 53.8% and a styrene selectivity of 96.7% at 773 K.
What type of reaction is a dehydrogenation?
Dehydrogenation is the a chemical reaction that involves the removal of hydrogen, usually from an organic molecule. It is the reverse of hydrogenation. Dehydrogenation is important, both as a useful reaction and a serious problem.