02183nas a2200241 4500008004100000022001400041245011100055210006900166260000800235300001000243490000800253520135800261653001901619653001801638653002501656653002201681653001301703100002601716700002101742700002301763700002901786856012601815 2024 eng d a0263-876200aExperimental and kinetic modelling studies for the design of fixed bed methanol reactor over CuZA catalyst0 aExperimental and kinetic modelling studies for the design of fix cMAY a79-900 v2053 a

Direct conversion of CO 2 via hydrogenation to value-added chemicals is a vital approach for utilising CO 2 emitted into the atmosphere. In this paper, a critical analysis of reaction kinetic modelling studies is explored in a fixed bed reactor to improve methanol yield for different H 2 to CO 2 ratios by simulating a lab-scale reactor for adiabatic and isothermal conditions. The feed inlet temperature and pressure variations are applied to study the effect of both configurations on methanol production. The results show that the isothermal configuration yields 2.76% more methanol yield compared to the adiabatic reactor. The effect of H 2 to CO 2 molar ratios of 3, 6 and 9 on the performance of the catalyst and the influence of CO and CO 2 hydrogenation is investigated with model simulations. The overall methanol yield is increased from 19.03% to 36.41% with increase in H 2 to CO 2 molar ratio from 3 to 9. Experiments are performed using commercial copper-based catalyst for different temperatures of 210, 230 and 250 degrees C at a pressure of 40 bar for H 2 /CO 2 of 3 and GHSV of 720 h -1 as well as at optimal temperature of 250 degrees C and 50 bar with varying H 2 /CO 2 of 3, 6, 9 for 3 g and 6 g catalyst. The maximum methanol yield of 2.53% and space time yield of 13.59 mg/g cat .h is obtained at H 2 /CO 2 ratio of 9.

10aCO2 conversion10aCuZA catalyst10aH2 toCO2 molar ratio10aKinetic modelling10aMethanol1 aBagwan, Farahanaz, M.1 aDongapure, Pavan1 aKulkarni, Amol, A.1 aVasireddy, Satyam, Naidu uhttps://library.ncl.res.in/content/experimental-and-kinetic-modelling-studies-design-fixed-bed-methanol-reactor-over-cuza02098nas a2200241 4500008004100000022001400041245012000055210006900175260000800244300001200252490000700264520120300271653002901474653002001503653004301523653004701566653003301613653000901646100002601655700002101681700002901702856012501731 2024 eng d a0360-319900aReaction kinetics for catalytic hydrogenation of quinoline to decahydroquinoline as liquid organic hydrogen carrier0 aReaction kinetics for catalytic hydrogenation of quinoline to de cNOV a102-1120 v923 a

The catalytic hydrogenation of quinoline to decahydroquinoline (DHQ) formation is studied for various parameters such as temperature, hydrogen pressure, reaction time, solvents, reactant-to-solvent ratio, and catalyst loading over 5%Pd loaded on alumina (Pd/Al2O3) to obtain optimal reaction conditions. The hydrogen uptake of quinoline in the liquid phase reaction using isopropylalcohol (IPA) is studied in an autoclave reactor. The optimum reaction parameters of 50 bar H2 pressure and 175oC with reactant to solvent ratio of 1:9 for reaction time of 5 h are observed. The effect of IPA solvent showed that hydrogen uptake of 6.91 wt% with complete hydrogenation of quinoline and DHQ yield of more than 99% is observed. The reaction kinetic model is developed for a simplified reaction mechanism and is simulated using the Markov Chain Monte Carlo (MCMC) simulation tool to predict the rate constants and the experimental observations are validated with the model predictions. The activation energy for quinoline hydrogenation to py-THQ formation is estimated to be 136.57 kJ/mol. It is envisaged that quinoline hydrogenation to pz-THQ is the rate-limiting step in the DHQ formation.

10aDecahydroquinoline (DHQ)10aHydrogen uptake10aLiquid organic hydrogen carrier (LOHC)10aMarkov chain Monte Carlo (MCMC) simulation10aThermal screening unit (TSU)10atool1 aBagwan, Farahanaz, M.1 aKinage, Anil, K.1 aVasireddy, Satyam, Naidu uhttps://library.ncl.res.in/content/reaction-kinetics-catalytic-hydrogenation-quinoline-decahydroquinoline-liquid-organic01883nas a2200253 4500008004100000022001400041245010100055210006900156260000800225300001100233490000700244520100500251653002901256653003001285653002001315653002301335653002201358653002701380100002601407700002401433700002101457700002901478856012201507 2026 eng d a0930-751600aReaction kinetics for dehydrogenation of decahydroquinoline to quinoline for hydrogen generation0 aReaction kinetics for dehydrogenation of decahydroquinoline to q cFEB ae701770 v493 a

Catalytic dehydrogenation of decahydroquinoline (DHQ) to quinoline is a promising pathway for hydrogen release in liquid organic hydrogen carrier systems. In this work, solvent-free DHQ dehydrogenation over Pd/Al2O3 is systematically investigated to evaluate hydrogen release performance and reaction kinetics. High DHQ conversion (83.9%) and degree of dehydrogenation (82.7%) are achieved at optimal reaction conditions. A power-law kinetic model based on a simplified reaction mechanism is developed and simulated using a Markov Chain Monte Carlo (MCMC) approach for estimation of rate constants and validation of concentration profiles with experimental data. The apparent activation energies are determined to be 45.85 kJ/mol for DHQ to 5,6,7,8-tetrahydroquinoline (bz-THQ) and 185.43 kJ/mol for bz-THQ to quinoline formation, identifying latter as the rate-limiting step. This framework provides mechanistic insight and supports the potential of DHQ as an efficient hydrogen carrier.

10aDecahydroquinoline (DHQ)10adegree of dehydrogenation10aDehydrogenation10arate-limiting step10aReaction kinetics10aWeisz-Prater criterion1 aBagwan, Farahanaz, M.1 aDadkar, Sarthak, S.1 aKinage, Anil, K.1 aVasireddy, Satyam, Naidu uhttps://library.ncl.res.in/content/reaction-kinetics-dehydrogenation-decahydroquinoline-quinoline-hydrogen-generation