A process for producing styrene by dehydrogenation of ethylbenzene comprising feeding steam and ethylbenzene to three or more dehydrogenation reactors connected in series, an intermediate heater for heating the reaction mixture through heat exchange with steam being provided between each of said dehydrogenation reactors, said steam being first used as a medium to heat the respective intermediate heaters, and then mixed with ethylbenzene supplied as the feed to the first of said series of reactors, wherein 3 to 10 mols of steam are mixed with one mol of ethylbenzene and the temperature and pressure at the inlet of the final dehydrogenation reactor are 600°-680° C. and 0.4-0.8 Kg/cm2 (abs.), respectively, is disclosed.

Process for producing styrene

The present invention relates to a process for the production of styrene by the catalytic dehydrogenation of ethylbenzene into styrene in the presence of steam which is, in a first stage, used for heating the reaction effluents, and then used as diluent for ethylbenzene. This process is characterized in that: a molar ratio of steam:ethylbenzene of between 5 and 13 is used, the temperature in the dehydrogenation reactors is between 580° and 645° C., the average pressure in the first reactor is 0.6-1 kg/cm2 and those in the second and the third reactors is 0.4-0.7 kg/cm2, and the hourly space velocity of liquid ethylbenzene is 0.20-0.35 h-1.

Process for production of styrene

A reactor system for effecting dehydrogenation reactions is disclosed comprised of an adiabatic reactor and a non-adiabatic reactor wherein the reactants are serially passed therethrough with the reactants being heated during passage through the latter reactor.

Process and apparatus for the dehydrogenation of alkylated aromatic hydrocarbons

A method for improving productivity and process stability in styrene monomer manufacturing system using a reaction system having multiple reactors connected in series, which can prevent destruction of the embedded catalyst and bending of a screen which supports catalyst and achieve homogeneous catalyst inactivation during the reaction by divergence of some portions of the feed containing steam and ethylbenzene and injection thereof into a certain point of the system.

Method for improving productivity and process stability in styrene manufacturing system having multiple reactors connected in series

Methods and systems for heating a reactor feed in a multi reactor hydrocarbon dehydrogenation process. The methods and systems are advantageously employed for the production of styrene by the catalytic dehydrogenation of ethylbenzene. The catalytic dehydrogenation process employs heating steam operating at a steam to oil ratio of about 1.0 or less and relatively low steam superheater furnace temperature, such that all components exposed to steam in the process (outside of the fired heaters) can be constructed with standard metallurgy.

Method of preheating dehydrogenation reactor feed

METHOD OF CATALYTICALLY DEHYDROGENATING AN ALKYLATED AROMATIC HYDROCARBON HAVING AT LEAST TWO CARBON ATOMS IN A SIDE-CHAIN TO A VINYLAROMATIC HYDROCARBON BY RAPIDLY PASSING THROUGH A CATALYST ZONE A FEEDSTOCK WHICH HAS BEEN HEATED TO THE REACTION TEMPERATURE AND HAS BEEN OBTAINED BY MIXING A PREHEATED MIXTURE CONTAINING THE ALKYLATED AROMATIC HYDROCARBON AND OPTIONALLY STEAM AND OPTIONALLY THE VINYLAROMATIC HYDROCARBON WITH STEAM HEATED TO A TEMPERATURE ABOVE THE TEMPERATURE OF REACTION. THE PREHEATED MIXTURE HAS A TEMPERATURE OF FROM 400* TO 620* C. AND THE STEAM HEATED TO ABOVE THE REACTION TEMPERATURE HAS A TEMPERATURE OF FROM 820* TO 1,100* C. AND THE RESULTING FEEDSTOCK HAS A BLEND TEMPERATURE OF FROM 550* TO 700* C., THE TIME TAKEN FOR MIXING THE PREHEATED MIXTURE WITH THE HEATED STEAM BEING LESS THAN 0.1 SECOND WHILE THE RESIDENCE TIME OF THE RESULTING FEEDSTOCK BETWEEN THE MIXING POINT AND THE POINT OF ENTRY INTO THE CATALYST ZONE IS LESS THAN 0.2 SECOND. THE PRODUCTS ARE IMPORTANT MONOMERS AND COMONOMERS.

Winfried Single Dipl-Ing

Papers

Catalytically dehydrogenating alkylated aromatic hydrocarbons

Verfahren zur katalytischen Dehydrierung eines alkylierten aromatischen Kohlenwasserstoffes