Question

Which is the best thermodyinimc package to preduce styeren from ethylbenzene by dehydrogenation and why?

Answer 1

Styrene is an important intermediate product in the petrochemical industry. The commercial demand for styrene grows at 6% per year. This popularity is mainly due to its recyclable character, which is not shared by other thermoplastics. About 90% of the total production of styrene is based on the catalytic dehydrogenation of ethylbenzene (EB). This reaction is reversible and endothermic, and the maximum conversion of EB under real process conditions is limited by thermodynamic equilibrium to about 45%. The industrial process is conducted at a high temperature, usually between 550 and 650°C. This temperature must be carefully controlled to avoid thermal stress on the catalyst, which can cause irreversible damage and most importantly the loss of selectivity by the formation of coke .The operating pressure is usually atmospheric or lower and a catalyst of Fe2O3, associated with other metallic oxides, is used

To supply the high energy load consumed by the highly endothermic reaction of dehydrogenation, a great quantity of steam is used in the reactor feed. It was shown that increase in styrene production over that of the industrial conventional fixed-bed unit is achievable, if design, operating parameters, and catalysts are properly chosen