Method of conducting an endothermic reaction in a packed-bed reactor with external energy addition

A method of carrying out an endothermic reaction in a stationary reactor having an active catalyst portion comprising first and second symmetric opposed portions flanked by a pair of inert reactor sections presenting two opposing outer ends, the reaction having a desired temperature profile within the reactor associated with an optimal conversion and product selectivity, the method comprising:

• passing a reaction mixture through the stationary reactor by introducing the mixture through the reactor first end;
• introducing heat at a first axially discrete location within the first symmetric portion to establish a desired temperature profile;
• catalyzing the endothermic reaction to produce a desired end product;
• and
• periodically reversing the flow of the reaction mixture by introducing the mixture at the second reactor end and switching the introduction of heat to a second discrete location within said second symmetrical reactor portion which is axially symmetrical to said first location, the rate of reversal being sufficient to reduce heat losses from the reactor.

A method of carrying out an endothermic reaction in a stationary reactor having an active catalyst portion comprising first and second symmetric opposed portions flanked by a pair of inert reactor sections presenting two opposing outer ends, the reaction having a desired temperature profile within the reactor associated with an optimal conversion and product selectivity, the method comprising:

• passing an ethylbenzene/steam reaction mixture, having a molar ratio of 6:1 and temperature of about 541 K through the stationary reactor by introducing the mixture through the reactor first end;
• introducing heat in the form of steam at a first axially discrete location within the first symmetric portion of catalyst to establish a desired temperature profile, sufficient steam being added to increase the steam/ethylbenezene molar ratio to 8:1;
• catalyzing ethylbenzene to produce styrene at the pressure of 2.3 atm;
• and
• periodically reversing the flow of the reaction mixture by introducing the steam/ethylbenezene mixture having a molar ratio of 6:1 at the second reactor end and switching the introduction of heat in the form of steam to a second discrete location within said second symmetrical reactor portion which is axially symmetrical to said first location, sufficient steam being added to increase the steam/ethylbenzene ratio to 8:1, the rate of reversal being in the range of 1 every 1-16 minutes.

A method of carrying out a catalyzed reaction of fluid reactant(s) utilizing the addition of added heat energy to produce desired reaction product(s) and comprising the steps of:

• providing a reactor having a catalyst bed presenting a catalytically active section;
• providing a reactant stream for passage into and through the active section of the catalyst bed;
• providing two inert regenerative heat exchange sections adjacent said catalyst bed in fluid communication therewith;
• directing the reactant stream into one of the inert sections for flow into the active section of the catalyst bed;
• adding and maintaining sufficient heat energy in the active section of the catalyst bed at discrete locations therein to achieve catalytic reaction of the reactant and to establish a desired temperature profile for said catalyzed reaction;
• allowing the reaction product produced in the active section of the catalyst bed to flow out of the reactor through another of the inert sections and to substantially prevent the occurrence of reverse reactions;
• monitoring the temperature profile of the catalytic reaction in the catalyst bed;
• and
• repetitively discontinuing direction of the reactant stream into one of the inert sections and shifting the reactant stream to another of the inert sections while at the same time shifting the reaction product exiting from the catalyst bed for flow through an inert section not then serving to direct reactant into the active section of the catalyst bed,
• said shifting of the reactant and reaction product stream from respective inert sections to other inert sections being carried out sufficiently repetitively to maintain a desired temperature profile in the reactor and effect trapping of energy in the inert section through which reaction product is exiting from the reactor catalyst bed.