Enhancing performance of three-phase catalytic packed-bed reactors

Our previous theoretical work predicted the possibility of enhancing three- phase packed-bed reactor performance by operating in the pulsing-flow regim e. This article deals with the experimental study of the beneficial effect of pulsing flow on reaction outcome. Hydrogenation of phenylacetylene, diss olved in n-tetradecane over Pt/alumina catalyst, was chosen as the experime ntal reaction system. This is a triangular reaction, with styrene and ethyl benzene as the desired intermediate and final products, respectively. With properly designed experiments, the reaction performance in pulsing flow and trickling-flow regimes was compared directly, The effects of process varia bles such as temperature, feed flow rates, and reactant concentration on re action behavior were studied. A simplified model to describe the qualitativ e trends was also developed. Both experiments and calculations show that th e yield of styrene is higher in pulsing flow than in trickling flow, which confirms the advantages of pulsing-flow operation predicted by the theoreti cal work.