@article { ISI:000228203100026, title = {Hydroformylation of 1-hexene using Rh/TPPTS complex exchanged on anion exchange resin: kinetic studies}, journal = {Journal of Molecular Catalysis A-Chemical}, volume = {232}, number = {1-2}, year = {2005}, month = {MAY}, pages = {179-186}, publisher = {ELSEVIER SCIENCE BV}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

The exchange of the Rh/Triphenylphosphine trisulfonate sodium [TPPTS] complex on to an anion exchange resin results in a stable heterogenized catalyst for the hydroformylation of alkenes. The kinetics of hydroformylation of 1-hexene using Rh/TPPTS complex exchanged on anion exchange resin to Amberlite IRA-93 has been investigated for the first time. The rate of the reaction was found to be dependent on the partial pressure of hydrogen and 1-hexene concentrations with a first order. A maximum in the rate with increasing partial pressure of carbon monoxide was observed. A rate model has been proposed which predicts the observed rate data within reasonable error. The activation energy was found to be 84.37 kJ/mol. (c) 2005 Elsevier B.V. All rights reserved.

}, keywords = {heterogenized catalyst, Hydroformylation, ion-exchange resin, kinetics, Rhodium}, issn = {1381-1169}, doi = {10.1016/j.molcata.2005.01.033}, author = {Diwakar, Makarand M. and Deshpande, R. M. and Chaudhari, Raghunath V.} } @article { ISI:000251763600036, title = {Modeling of bubble column slurry reactor for reductive alkylation of p-phenylenediamine}, journal = {Chemical Engineering Science}, volume = {62}, number = {24, SI}, year = {2007}, note = {8th International Conference on Gas-Liquid and Gas-Liquid-Solid Reactor Engineering, Indian Inst Technol Delhi, New Delhi, INDIA, DEC 16-19, 2007}, month = {DEC}, pages = {7290-7304}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, type = {Article}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

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{\textquoteright}-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 {\textquoteleft}mixing cell approach{\textquoteright}. 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.

}, keywords = {bubble columns, CFD, kinetics, Mathematical modeling, Reductive alkylation}, issn = {0009-2509}, doi = {10.1016/j.ces.2007.08.065}, author = {Chaudhari, Amit S. and Rampure, Mohan R. and Ranade, Vivek V. and Jaganathan, Rengaswamy and Chaudhari, Raghunath V.} } @article { ISI:000268905100015, title = {Kinetics of arylation of 3-bromo-benzophenone with n-butylacrylate using NC palladacycle catalyst}, journal = {Journal of Molecular Catalysis A-Chemical}, volume = {309}, number = {1-2}, year = {2009}, month = {AUG}, pages = {111-116}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

The kinetics of arylation of n-butylacrylate (n-BA) with 3-bromo-benzophenone (BBP) using a monomeric palladacycle complex [Pd(ppy)(PPh(3))(OTs)](ppy=2-phenylpyridine) catalyst has been studied. The effect of concentration of the substrate, base (NaOAc), and catalyst was studied at three different temperatures (413-433 K). The rate was found to be first order with respect to catalyst, first order tending to zero order with respect to n-butylacrylate and NaOAc concentrations. The rate passed through a maximum with variation of BBP concentration. The observed results have been explained on the basis of formation of Pd species (PdX(2), PdX(3)(-), PdX(4)(2-), and Pd(2)X(6)(2-)) which are inactive for the Heck reaction. Various empirical rate equations were considered to fit the rate data and the best fitting model has been selected. The rates predicted by model were found to be in good agreement with the observed experimental data. (C) 2009 Elsevier B.V. All rights reserved.

}, keywords = {Arylation, Heck reaction, kinetics, Palladacycle}, issn = {1381-1169}, doi = {10.1016/j.molcata.2009.05.003}, author = {Atla, Shashi B. and Rajurkar, Kalpendra B. and Kelkar, Ashutosh A. and Chaudhari, Raghunath V.} } @article { ISI:000276206700037, title = {Kinetics of reductive alkylations of phenylenediamines: influence of substrates isomeric structure}, journal = {Chemical Engineering Science}, volume = {65}, number = {1, SI}, year = {2010}, note = {20th International Symposium on Chemical Reaction Engineering, Kyoto, JAPAN, SEP, 2008}, month = {JAN}, pages = {232-239}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

Reductive alkylation of ortho-, meta- and para-phenylenediamines (PDAs) with methyl ethyl ketone (MEK) has been studied in a semi-batch slurry reactor in the presence of a commercial 3\% Pt/Al(2)O(3) catalyst. It was observed that the PDA isomers differ remarkably from each other in their activity in reductive alkylation and product distribution. The activity was found to decrease in the following order: PPDA \> OPDA \> MPDA. To understand the substrate structure-activity correlation, the homogeneous equilibrium reactions involved in the alkylation step and the overall catalytic reactions were studied separately. Kinetics of reductive alkylation of PDAs with MEK as a solvent and alkylating agent with 3\% Pt/Al(2)O(3) catalyst was studied in a semi-batch slurry reactor over a temperature range of 373-453K and pressure range of 2.07-6.21 MPa. Semi-batch slurry reactor models were developed and kinetic parameters were estimated by fitting the integral batch reactor data at different temperatures to understand the influence of different reaction steps on the activity and selectivity of different products. Published by Elsevier Ltd.

}, keywords = {Batch, catalysis, kinetics, Multiphase reactions, Phenylenediamines, Reaction engineering, Reductive alkylation}, issn = {0009-2509}, doi = {10.1016/j.ces.2009.06.065}, author = {Roy, Debdut and Chaudhari, Amit S. and Chaudhari, Raghunath V.} }