Catalysis of Organic..

O’Keefe, Jiang, Ng and Rempel 367OOOH 2O+ Ac – H 2 O(DIBK)+ H OH2(isomesityloxide)O(mesityl oxide)O+ Ac – H 2 O+ AcOO(MIBK)+H 2 + Ac– H 2 OOH(DMHA)(MIBC)(phorone)OOHAc + C 7 H 12(mesitylene)(α-isophorone)(β-isophorone)Higher molecular weight productsFigure 2. Undesirable consecutive reactions in the synthesis of MIBKThe latter approach affords greater flexibility allowing the catalyst and reactionzones to be designed and optimized independently for each reaction step. In thisconfiguration, it is possible to design the hydrogenation catalyst in a manner toprotect the active sites and facilitate hydrogen transport. Previously, we havedeveloped a CD process for the production of DAA from acetone (8). A CD processfor the one step synthesis of MIBK appears to be a simple extension of this DAAprocess. However, the introduction of hydrogen to this system opens up numerouspossible reaction pathways. Most noteworthy is the hydrogenation of acetone toproduce 2-propanol, which is a significant competing reaction for the expected CDprocess conditions (2,4). In this work, the results of a preliminary pilot scaleinvestigation of the one step synthesis of MIBK in a CD pilot plant operating in acontinuous mode utilizing two commercial catalysts in separate reaction zones isreported. The objective was to obtain a cursory assessment of the process byinvestigating the effects of the reaction temperature as well as the hydrogen andacetone feed rates on the MIBK yield and selectivity and to establish the technicalfeasibility of a CD process for MIBK synthesis utilizing two separate reaction zones.