02291nas a2200253   4500008004100000022001400041245009200055210006900147260010600216300001400322490000700336520136000343653001901703653000801722653001301730653002601743653002501769100002401794700002301818700002201841700002701863700002901890856011801919       2007                        eng d  a0009-250900aModeling of bubble column slurry reactor for reductive alkylation of p-phenylenediamine0 aModeling of bubble column slurry reactor for reductive alkylatio  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcDEC  a7290-73040 v623 a<p>A bubble column slurry reactor (BCSR) model has been developed for the reductive alkylation of p-phenylenediamine (PPDA) with methyl ethyl ketone (MEK) to N, N'-di-secondary-alkyl-p-phenylenediamine (Di-amine). This particular reaction system is commercially relevant and involves a combination of parallel and consecutive reactions comprising equilibrium non-catalytic (homogeneous) and catalytic (heterogeneous) steps. The proposed model is based on the `mixing cell approach'. In this work the mixing cell approach has been extended by including a liquid backflow stream from all but the bottommost mixing cell. The model incorporates the contributions of gas-liquid and liquid-solid mass transfer, heat effects, and complex multistep reaction kinetics. CFD model is used to estimate the extent of backflow among mixing cells and its dependence on operating parameters. The effect of gas and liquid velocities, catalyst loading, inlet PPDA concentration, and temperature on the conversion, selectivity, global rate of hydrogenation, and temperature rise is discussed. The comparison of the current approach with the traditional mixing cell model is discussed. The BCSR model presented here will be useful to provide guidelines for designing and improving overall performance of bubble column reactors. (C) 2007 Elsevier Ltd. All rights reserved.</p>10abubble columns10aCFD10akinetics10aMathematical modeling10aReductive alkylation1 aChaudhari, Amit, S.1 aRampure, Mohan, R.1 aRanade, Vivek, V.1 aJaganathan, Rengaswamy1 aChaudhari, Raghunath, V.  uhttp://library.ncl.res.in/content/modeling-bubble-column-slurry-reactor-reductive-alkylation-p-phenylenediamine-0