Abstract: A process is disclosed for the production of methanol from a synthesis gas stream comprising hydrogen and carbon dioxide in which an equilibrium reaction to methanol is achieved by conducting the reaction and the product separation in a pressure swing adsorption and reaction zone containing a uniformly distributed adsorbent for the selective adsorption of methanol and a catalyst for the equilibrium conversion of the synthesis gas to methanol. More specifically, the process achieves the production of methanol by the reaction of the hydrogen and the carbon oxide with the simultaneous adsorption of the product at the same temperature and pressure. The passing of the synthesis stream to the bed is terminated and the bed is purged and depressurized to desorb the methanol product. In one embodiment, the bed is cocurrently purged with at least a portion of an effluent stream prior to depressurizing the bed.

Abstract: In a combination crystallization/xylene isomerization process for producing para-xylene crystals, the recovery section is modified to accommodate crystallizing and separating para-xylene crystals at two different temperatures (a higher temperature followed by a lower temperature). The benefit is a reduction in the overall energy cost of the process.

Abstract: The eutectic limit of para-xylene crystallization is overcome by enriching the concentration of para-xylene of the crystallization feed. This is accomplished by passing the crystallization feed stream through a selective adsorption zone to produce a para-xylene-enriched stream and a para-xylene-depleted stream. The para-xylene-depleted stream is passed to an isomerization zone to re-equilibrate the xylene mixture, thereby producing additional para-xylene. The para-xylene-enriched stream is passed to a crystallization zone to produce high purity para-xylene. The result is an increase in the overall para-xylene recovery.

Abstract: The present invention is an integrated catalytic reforming/hydrodealkylation process that maximizes benzene recovery by incorporating refrigeration and pressure swing adsorption separation units. In the refrigeration separation unit, liquid reformate is used as a sponge oil to recover benzene from a hydrodealkylation purge gas stream, which in the past has been vented. The pressure swing adsorption unit remove impurities from a hydrogen-rich gas stream prior to use in the hydrodealkylation unit.