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Aniruddha B Pandit - One of the best experts on this subject based on the ideXlab platform.

  • ultrasound assisted synthesis of biodiesel from palm fatty acid distillate
    Industrial & Engineering Chemistry Research, 2009
    Co-Authors: Vishwanath G Deshmane, Parag R Gogate, Aniruddha B Pandit
    Abstract:

    The present work aims at exploiting palm fatty acid distillate as a starting raw material for synthesis of biodiesel with the aim of reducing the cost of production. Esterification of palm fatty acid distillate (PFAD) with methanol in the presence of concentrated H 2 SO 4 as a catalyst has been investigated in the presence of ultrasonic irradiations at 22 kHz frequency and 120 W as supplied power dissipation. The effect of different operating parameters such as molar ratio of reactants, catalyst quantity, and operating temperature have been studied with the aim of process optimization. It has been observed that ultrasound significantly enhances the rate of reaction and also the extent of Equilibrium Conversion. A certain degree of Conversion attributed to heterogeneity of the system, which adds to mass transfer resistances under conventional approach, appears to get eliminated due to ultrasound. Conversion levels of more than 90% have been observed with the use of ultrasound in about 150 min under ambient operating conditions.

  • ultrasound assisted synthesis of isopropyl esters from palm fatty acid distillate
    Ultrasonics Sonochemistry, 2009
    Co-Authors: Vishwanath G Deshmane, Parag R Gogate, Aniruddha B Pandit
    Abstract:

    Esterification is one of the most preferred synthesis routes for organic esters which are most frequently used as plasticizers, solvents and perfumery and flavour chemicals. The present work deals with acid catalyzed synthesis of isopropyl esters from palm fatty acid distillate (PFAD) in the presence of ultrasonic irradiations operating at 25 kHz frequency and 1 kW of supplied power. Effect of different operating parameters such as molar ratio of reactants, catalyst quantity and operating temperature has been studied with an aim of optimization. It has been observed that ultrasound enhances the rate of reaction and the extent of Equilibrium Conversion. The optimum parameters for this process have been found to be 1:5 molar ratio of PFAD to isopropanol, catalyst concentration of 5% of PFAD and 60 °C reaction temperature. Maximum Conversion levels of about 80% have been obtained in 6 h of reaction time under these optimized conditions. Analysis of the kinetic data indicates that the reaction follows first order reversible path.

  • process intensification of synthesis process for medium chain glycerides using cavitation
    Chemical Engineering Journal, 2008
    Co-Authors: Vishwanath G Deshmane, Parag R Gogate, Aniruddha B Pandit
    Abstract:

    Abstract Cavitation results in conditions of local hot spots, turbulence and liquid circulation in the reactor which can result into intensification of chemical reactions. The present work investigates the effect of cavitating conditions on the synthesis process of medium chain glycerides (MCG) based on the esterification reaction between the fatty acids and glycerol. Effect of molar ratio and temperature on the rate of reaction and Equilibrium Conversion in the presence of ultrasound has been studied. It has been conclusively established that cavitation indeed results in substantial degree of intensification as compared to the conventional approach reported in the literature. Under optimized operating conditions of mole ratio (1:3) and temperature (90 °C), Equilibrium Conversion of 98.5% has been obtained in about 6 h of reaction time using cavitation.

Adele Brunetti - One of the best experts on this subject based on the ideXlab platform.

  • Dry Reforming of Methane in a Pd-Ag Membrane Reactor: Thermodynamic and Experimental Analysis
    MDPI AG, 2018
    Co-Authors: Alessio Caravella, Adele Brunetti, Monia Grandinetti, Giuseppe Barbieri
    Abstract:

    The present work is a study of CO2 Reforming of Methane (DRM) carried out in a catalytic Pd-based membrane reactor. A detailed thermodynamic analysis is carried out, calculating the chemical Equilibrium parameters in two different cases: (a) DRM along with the Reverse Water Gas Shift (RWGS) reaction and (b) DRM along with both RWGS and the Boudouard Reaction (BR). The performance of membrane reactor is then experimentally analyzed in terms of methane Conversion, hydrogen recovery and H2/CO reaction selectivity by varying feed pressure and CO2/CH4 feed molar ratio and 500 °C and GHSV = 100 h−1. Among the obtained results, a CH4 Conversion of about 26% and a H2 recovery of 47% are achieved at low feed pressures, exceeding the traditional reactor Equilibrium Conversion. This effect can be attributed to the favorable thermodynamics coupled to the hydrogen permeation through the membrane. This study further demonstrates the general effectiveness of membrane-integrated reaction processes, which makes the production of syngas more efficient and performing, providing important environmental benefits

  • direct Conversion of n butane to isobutene in a membrane reactor thermodynamic analysis
    Industrial & Engineering Chemistry Research, 2013
    Co-Authors: Hamid Almegren, Giuseppe Barbieri, Ilaria Mirabelli, Adele Brunetti, Enrico Drioli, Mohammed C Alkinany
    Abstract:

    Isobutene is an important intermediate compound in the petrochemical industry for the production of polymers (butyl rubber, polybutene, and isoprene) and methyl tert-butyl ether. In this work, the n-butane dehydroisomerization reaction in a membrane reactor (MR) was investigated by thermodynamic analysis in a wide range of temperatures, reaction pressures, and Equilibrium hydrogen partial pressures, by means of a simplified reaction scheme. The shift of the Equilibrium Conversion in an MR was evaluated by taking into account the chemical reaction Equilibrium and the permeative Equilibrium through a 100% hydrogen-selective membrane. The evaluated limits imposed by thermodynamics on an MR are much wider than those of a traditional reactor so that a Conversion of about 7 times higher could be obtained over that of the traditional process under a set of operating conditions. This gives a powerful indication on how the use of an MR can extend the thermodynamic limits of this reaction, in terms of Conversion, e...

  • a porous stainless steel supported silica membrane for wgs reaction in a catalytic membrane reactor
    Chemical Engineering Science, 2007
    Co-Authors: Adele Brunetti, Giuseppe Barbieri, Enrico Drioli, T Granato, Kueirrarn Lee
    Abstract:

    Abstract In this work the water gas shift (WGS) reaction in a membrane reactor (MR) using a porous stainless steel supported silica membrane and a CuO / CeO 2 based commercial catalyst was analysed in a temperature range of 220–290 °C up to 600 kPa. The reaction pressure effect on the CO Conversion and permeate stream composition was followed with special attention paid to the significant performance improvement in the MR. The best operating condition for the MR was identified as 280 ∘ C and 400 kPa, obtaining a CO Conversion of 95% with an increment of 8% with respect to TR. Furthermore, the membrane permeance ( H 2 : 9.7 – 29 ; CO : 0.3 – 1.1 ; CO 2 : 0.4 – 1.5 nmol / m 2 s Pa ) and selectivity ( H 2 / CO , H 2 / CO 2 ranging from 15 to 40) and the influence of other gases on H 2 permeation were evaluated before and after reaction testing. No inhibition effect of other gases on the hydrogen flux in all cases was observed. An MR using silica membranes was successfully employed in the WGS reaction, obtaining always higher Conversion than with a traditional reactor (TR) and also (at T > 250 ∘ C ) exceeding the TR Equilibrium Conversion (TREC).

  • wgs reaction in a membrane reactor using a porous stainless steel supported silica membrane
    Chemical Engineering and Processing, 2007
    Co-Authors: Adele Brunetti, Giuseppe Barbieri, Enrico Drioli, K H Lee, Bongkuk Sea, D W Lee
    Abstract:

    Abstract Water gas shift reaction for hydrogen production was studied in a catalytic membrane reactor using a supported silica membrane at 220–290 °C temperature and 2–6 bar pressure ranges. A CO Conversion higher than the thermodynamic Equilibrium of a traditional reactor was obtained. The best result, 95% CO Conversion, was achieved at 4 bar and 280 °C. The membrane was also characterized in terms of permeance and selectivity by means of permeation tests carried out before and after reaction. In addition, permeance and separation factor were also measured during the reaction. Permeance of all species (H2: 9.7–29; CO: 0.3–1.1; CO2: 0.4–1.5 nmol/m2 s Pa), selectivity (H2/CO, H2/CO2 and H2/N2) ranging from 15 to 40 and separation factors (H2/CO = 20–45), showed no dependence on the related permeation driving force. Differences between selectivity and separation factor were registered. Furthermore, no inhibition effects of other gases on the hydrogen flux were observed. The membrane was prepared by the soaking roller procedure depositing a silica layer on a stainless steel support with an intermediate γ-alumina layer. The membrane reactor allowing selective hydrogen permeation presents a good performance exceeding also the Equilibrium Conversion of a traditional reactor.

Giuseppe Barbieri - One of the best experts on this subject based on the ideXlab platform.

  • Dry Reforming of Methane in a Pd-Ag Membrane Reactor: Thermodynamic and Experimental Analysis
    MDPI AG, 2018
    Co-Authors: Alessio Caravella, Adele Brunetti, Monia Grandinetti, Giuseppe Barbieri
    Abstract:

    The present work is a study of CO2 Reforming of Methane (DRM) carried out in a catalytic Pd-based membrane reactor. A detailed thermodynamic analysis is carried out, calculating the chemical Equilibrium parameters in two different cases: (a) DRM along with the Reverse Water Gas Shift (RWGS) reaction and (b) DRM along with both RWGS and the Boudouard Reaction (BR). The performance of membrane reactor is then experimentally analyzed in terms of methane Conversion, hydrogen recovery and H2/CO reaction selectivity by varying feed pressure and CO2/CH4 feed molar ratio and 500 °C and GHSV = 100 h−1. Among the obtained results, a CH4 Conversion of about 26% and a H2 recovery of 47% are achieved at low feed pressures, exceeding the traditional reactor Equilibrium Conversion. This effect can be attributed to the favorable thermodynamics coupled to the hydrogen permeation through the membrane. This study further demonstrates the general effectiveness of membrane-integrated reaction processes, which makes the production of syngas more efficient and performing, providing important environmental benefits

  • membrane reactor Equilibrium Conversion
    2015
    Co-Authors: Giuseppe Barbieri
    Abstract:

    The Equilibrium constant of any reaction is function of temperature only. The Equilibrium of a conventional/traditional reacting system is function only of the thermodynamic variables (temperature, pressure, and mixture composition). It is independent from the reactor model (continuous stirred tank reactor, plug flow reactor, batch reactor, etc.), fluid dynamics (mixing, diffusion, etc.), heat exchange (isothermal, adiabatic, or no-isothermal reactor), reactor size, etc. since the Equilibrium is reached when variation in temperature, pressure, and composition is no longer present in the chemical system. This condition is mathematically expressed by the following equations set valid for a reacting closed (no mass transfer with the environment) system consisting of N reactions.

  • direct Conversion of n butane to isobutene in a membrane reactor thermodynamic analysis
    Industrial & Engineering Chemistry Research, 2013
    Co-Authors: Hamid Almegren, Giuseppe Barbieri, Ilaria Mirabelli, Adele Brunetti, Enrico Drioli, Mohammed C Alkinany
    Abstract:

    Isobutene is an important intermediate compound in the petrochemical industry for the production of polymers (butyl rubber, polybutene, and isoprene) and methyl tert-butyl ether. In this work, the n-butane dehydroisomerization reaction in a membrane reactor (MR) was investigated by thermodynamic analysis in a wide range of temperatures, reaction pressures, and Equilibrium hydrogen partial pressures, by means of a simplified reaction scheme. The shift of the Equilibrium Conversion in an MR was evaluated by taking into account the chemical reaction Equilibrium and the permeative Equilibrium through a 100% hydrogen-selective membrane. The evaluated limits imposed by thermodynamics on an MR are much wider than those of a traditional reactor so that a Conversion of about 7 times higher could be obtained over that of the traditional process under a set of operating conditions. This gives a powerful indication on how the use of an MR can extend the thermodynamic limits of this reaction, in terms of Conversion, e...

  • a porous stainless steel supported silica membrane for wgs reaction in a catalytic membrane reactor
    Chemical Engineering Science, 2007
    Co-Authors: Adele Brunetti, Giuseppe Barbieri, Enrico Drioli, T Granato, Kueirrarn Lee
    Abstract:

    Abstract In this work the water gas shift (WGS) reaction in a membrane reactor (MR) using a porous stainless steel supported silica membrane and a CuO / CeO 2 based commercial catalyst was analysed in a temperature range of 220–290 °C up to 600 kPa. The reaction pressure effect on the CO Conversion and permeate stream composition was followed with special attention paid to the significant performance improvement in the MR. The best operating condition for the MR was identified as 280 ∘ C and 400 kPa, obtaining a CO Conversion of 95% with an increment of 8% with respect to TR. Furthermore, the membrane permeance ( H 2 : 9.7 – 29 ; CO : 0.3 – 1.1 ; CO 2 : 0.4 – 1.5 nmol / m 2 s Pa ) and selectivity ( H 2 / CO , H 2 / CO 2 ranging from 15 to 40) and the influence of other gases on H 2 permeation were evaluated before and after reaction testing. No inhibition effect of other gases on the hydrogen flux in all cases was observed. An MR using silica membranes was successfully employed in the WGS reaction, obtaining always higher Conversion than with a traditional reactor (TR) and also (at T > 250 ∘ C ) exceeding the TR Equilibrium Conversion (TREC).

  • wgs reaction in a membrane reactor using a porous stainless steel supported silica membrane
    Chemical Engineering and Processing, 2007
    Co-Authors: Adele Brunetti, Giuseppe Barbieri, Enrico Drioli, K H Lee, Bongkuk Sea, D W Lee
    Abstract:

    Abstract Water gas shift reaction for hydrogen production was studied in a catalytic membrane reactor using a supported silica membrane at 220–290 °C temperature and 2–6 bar pressure ranges. A CO Conversion higher than the thermodynamic Equilibrium of a traditional reactor was obtained. The best result, 95% CO Conversion, was achieved at 4 bar and 280 °C. The membrane was also characterized in terms of permeance and selectivity by means of permeation tests carried out before and after reaction. In addition, permeance and separation factor were also measured during the reaction. Permeance of all species (H2: 9.7–29; CO: 0.3–1.1; CO2: 0.4–1.5 nmol/m2 s Pa), selectivity (H2/CO, H2/CO2 and H2/N2) ranging from 15 to 40 and separation factors (H2/CO = 20–45), showed no dependence on the related permeation driving force. Differences between selectivity and separation factor were registered. Furthermore, no inhibition effects of other gases on the hydrogen flux were observed. The membrane was prepared by the soaking roller procedure depositing a silica layer on a stainless steel support with an intermediate γ-alumina layer. The membrane reactor allowing selective hydrogen permeation presents a good performance exceeding also the Equilibrium Conversion of a traditional reactor.

Anders Holmen - One of the best experts on this subject based on the ideXlab platform.

  • characteristics of integrated micro packed bed reactor heat exchanger configurations in the direct synthesis of dimethyl ether
    Chemical Engineering and Processing, 2013
    Co-Authors: Fatemeh Hayer, Hamidreza Bakhtiarydavijany, Rune Myrstad, Peter Pfeifer, Anders Holmen, Hilde J Venvik
    Abstract:

    Abstract The performance of three integrated micro packed bed reactor-heat exchangers (IMPBRHEs) for direct DME synthesis over physical mixtures of CuO–ZnO–Al 2 O 3 and γ-Al 2 O 3 catalysts was experimentally investigated. Systematic variations in reactor and slit dimensions and configuration were analyzed in terms of thermal behaviour, mass transfer, pressure drop and residence time distribution (RTD). The pressure drop was always small ( Re  = 0.1–2. A narrow RTD was estimated by the dispersion analysis. Careful temperature measurements confirmed that the reaction temperature is mainly controlled by the oil heat exchange to give a practically uniform temperature profile for set inlet oil temperatures of 220–320 °C. The micro packed beds were found free of the internal as well as external mass transfer limitations, as showed by no significant change in the CO Conversion and DME yield for different catalyst particle sizes, no effect of varying the linear gas velocity, and no effect of manipulating reactant diffusion coefficient. Packed bed microstructured reactors hence provide an isobaric and isothermal environment free from transport limitations for the direct DME synthesis, in the kinetic regime as well as at Equilibrium Conversion.

  • characteristics of an integrated micro packed bed reactor heat exchanger for methanol synthesis from syngas
    Chemical Engineering Journal, 2011
    Co-Authors: Hamidreza Bakhtiarydavijany, Fatemeh Hayer, Xuyen Kim Phan, Rune Myrstad, Hilde J Venvik, Peter Pfeifer, Anders Holmen
    Abstract:

    Abstract The main characteristics of a multi-slit Integrated Micro Packed Bed Reactor-Heat Exchanger (IMPBRHE) for compact synthesis of methanol from syngas over a Cu/ZnO/Al 2 O 3 catalyst under industrial operating conditions (80 bar and 523 K) were investigated. The reaction experiments show that near Equilibrium Conversion per pass is achievable at low contact times (about 470 ms g/ml). The experiments show superior heat removal capability from the catalytic slits through isothermal conditions. Pressure drop measurements in agreement with calculation by Ergun equation indicate an isobaric reaction media in the slits. The IMPBRHE shows promising features for further research on process intensification and miniaturization.

Enrico Drioli - One of the best experts on this subject based on the ideXlab platform.

  • direct Conversion of n butane to isobutene in a membrane reactor thermodynamic analysis
    Industrial & Engineering Chemistry Research, 2013
    Co-Authors: Hamid Almegren, Giuseppe Barbieri, Ilaria Mirabelli, Adele Brunetti, Enrico Drioli, Mohammed C Alkinany
    Abstract:

    Isobutene is an important intermediate compound in the petrochemical industry for the production of polymers (butyl rubber, polybutene, and isoprene) and methyl tert-butyl ether. In this work, the n-butane dehydroisomerization reaction in a membrane reactor (MR) was investigated by thermodynamic analysis in a wide range of temperatures, reaction pressures, and Equilibrium hydrogen partial pressures, by means of a simplified reaction scheme. The shift of the Equilibrium Conversion in an MR was evaluated by taking into account the chemical reaction Equilibrium and the permeative Equilibrium through a 100% hydrogen-selective membrane. The evaluated limits imposed by thermodynamics on an MR are much wider than those of a traditional reactor so that a Conversion of about 7 times higher could be obtained over that of the traditional process under a set of operating conditions. This gives a powerful indication on how the use of an MR can extend the thermodynamic limits of this reaction, in terms of Conversion, e...

  • a porous stainless steel supported silica membrane for wgs reaction in a catalytic membrane reactor
    Chemical Engineering Science, 2007
    Co-Authors: Adele Brunetti, Giuseppe Barbieri, Enrico Drioli, T Granato, Kueirrarn Lee
    Abstract:

    Abstract In this work the water gas shift (WGS) reaction in a membrane reactor (MR) using a porous stainless steel supported silica membrane and a CuO / CeO 2 based commercial catalyst was analysed in a temperature range of 220–290 °C up to 600 kPa. The reaction pressure effect on the CO Conversion and permeate stream composition was followed with special attention paid to the significant performance improvement in the MR. The best operating condition for the MR was identified as 280 ∘ C and 400 kPa, obtaining a CO Conversion of 95% with an increment of 8% with respect to TR. Furthermore, the membrane permeance ( H 2 : 9.7 – 29 ; CO : 0.3 – 1.1 ; CO 2 : 0.4 – 1.5 nmol / m 2 s Pa ) and selectivity ( H 2 / CO , H 2 / CO 2 ranging from 15 to 40) and the influence of other gases on H 2 permeation were evaluated before and after reaction testing. No inhibition effect of other gases on the hydrogen flux in all cases was observed. An MR using silica membranes was successfully employed in the WGS reaction, obtaining always higher Conversion than with a traditional reactor (TR) and also (at T > 250 ∘ C ) exceeding the TR Equilibrium Conversion (TREC).

  • wgs reaction in a membrane reactor using a porous stainless steel supported silica membrane
    Chemical Engineering and Processing, 2007
    Co-Authors: Adele Brunetti, Giuseppe Barbieri, Enrico Drioli, K H Lee, Bongkuk Sea, D W Lee
    Abstract:

    Abstract Water gas shift reaction for hydrogen production was studied in a catalytic membrane reactor using a supported silica membrane at 220–290 °C temperature and 2–6 bar pressure ranges. A CO Conversion higher than the thermodynamic Equilibrium of a traditional reactor was obtained. The best result, 95% CO Conversion, was achieved at 4 bar and 280 °C. The membrane was also characterized in terms of permeance and selectivity by means of permeation tests carried out before and after reaction. In addition, permeance and separation factor were also measured during the reaction. Permeance of all species (H2: 9.7–29; CO: 0.3–1.1; CO2: 0.4–1.5 nmol/m2 s Pa), selectivity (H2/CO, H2/CO2 and H2/N2) ranging from 15 to 40 and separation factors (H2/CO = 20–45), showed no dependence on the related permeation driving force. Differences between selectivity and separation factor were registered. Furthermore, no inhibition effects of other gases on the hydrogen flux were observed. The membrane was prepared by the soaking roller procedure depositing a silica layer on a stainless steel support with an intermediate γ-alumina layer. The membrane reactor allowing selective hydrogen permeation presents a good performance exceeding also the Equilibrium Conversion of a traditional reactor.

  • Equilibrium Conversion for a pd based membrane reactor dependence on the temperature and pressure
    Chemical Engineering and Processing, 2003
    Co-Authors: Giuseppe Marigliano, Giuseppe Barbieri, Enrico Drioli
    Abstract:

    Abstract A thermodynamic tool based on the ‘reactor in series method’ was used to evaluate the Equilibrium Conversion of dehydrogenation reactions such as methane steam reforming (MSR) and water gas shift (WGS) in a Pd-based membrane reactor (MR). The permeation Equilibrium, expressed by the equality of the H 2 partial pressure on reaction and permeate sides, was imposed as the further constrain for MR. The Equilibrium Conversion shift is an increasing function of the sweep factor, which is an index of the extractive capacity of the membrane system. The Equilibrium Conversion of a MR was analysed as a function of temperature and pressure. It shows the same trend vs. temperature for MR and traditional reactor (TR). On the contrary, pressure play a very important role because it has a different influence on the Equilibrium of MR with respect to a TR. In particular, the positive effect on thermodynamic Conversion was shown also for the MSR reaction characterised by Δ ν >0.