Abstract: The present invention discloses a process and apparatus for improving the catalyst life and efficiency in a gas flow catalyst bed reactor assembly. The reactor comprises an outer reaction vessel, an inner displacement cylinder, and an annular catalyst bed surrounding the displacement cylinder having a top half and a bottom half. Fluid flow improvement is achieved by adding at least one baffle to the top half of the displacement cylinder to improve uniformity of fluid flow in the reaction vessel and across the catalyst bed. Also disclosed is a process for improving fluid flow uniformity in a gas phase reactor comprising an outer reaction vessel, an inner displacement vessel having a top half and a bottom half and a reaction outer surface and an inert inner space, and an annular catalyst bed. The process comprises conducting fluid flow simulations using actual reactor conditions. During simulation, baffles are added on the outer reaction surface of the displacement reactor to improve simulated fluid flow.

Abstract: The present invention discloses a process and apparatus for improving the catalyst life and efficiency in a gas flow catalyst bed reactor assembly. The reactor comprises an outer reaction vessel, an inner displacement cylinder, and an annular catalyst bed surrounding the displacement cylinder having a top half and a bottom half. Fluid flow improvement is achieved by adding at least one baffle to the top half of the displacement cylinder to improve uniformity of fluid flow in the reaction vessel and across the catalyst bed. Also disclosed is a process for improving fluid flow uniformity in a gas phase reactor comprising an outer reaction vessel, an inner displacement vessel having a top half and a bottom half and a reaction outer surface and an inert inner space, and an annular catalyst bed. The process comprises conducting fluid flow simulations using actual reactor conditions. During simulation, baffles are added on the outer reaction surface of the displacement reactor to improve simulated fluid flow.

Abstract: The present invention is directed to an apparatus and method for the distillation of a readily polymerizable vinyl aromatic compound employing a polymerization inhibitor. The vinyl aromatic compound is subjected to distillation in at least one fractionation column having at least one reboiler for maintaining the bottoms of said column at a proper temperature. The reboiler includes a heating section and a vapor phase section. The bottoms fraction from the fractionation column is cycled to the reboiler and subjected to heat to vaporize at least a portion of the bottoms fraction to form a vapor phase in the vapor section, A slip stream of the bottoms fraction is introduced to the vapor phase section of the reboiler. The slipstream contains polymerization inhibitor that had been added to the process at the fractionation column. The invention reduces fouling at the reboilers. The slipstream is optionally introduced to the reboiler using one or more spray nozzles.