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Direct synthesis of hydrogen peroxide in a trickle bed reactor / Pierdomenico Biasi in Industrial & engineering chemistry research, Vol. 51 N° 26 (Juillet 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 26 (Juillet 2012) . - pp. 8883-8890 Titre : Direct synthesis of hydrogen peroxide in a trickle bed reactor : Comparison of Pd - based catalysts Type de document : texte imprimé Auteurs : Pierdomenico Biasi, Auteur ; Paolo Canu, Auteur ; Federica Menegazzo, Auteur Année de publication : 2012 Article en page(s) : pp. 8883-8890 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Catalyst  Trickle  bed  reactor  Hydrogen  peroxide Résumé : Palladium catalysts based on different supports, silica (SiO2), zirconia (Z), sulfated ceria (CeS), and sulfated zirconia (ZS), previously tested in a semibatch reactor, were chosen to demonstrate how the direct synthesis process can be improved by continuous operation in a three-phase fixed bed. The gas and liquid flow rates were systematically varied to find suitable combinations for a maximum hydrogen peroxide production rate and selectivity. Different catalysts gave the same results in terms of selectivity and production rate with different operating conditions. A selectivity of 60% and 70% was found with two different catalysts (namely, Pd-ZS and Pd-CeS). Very interestingly those selectivities were found with different gas and liquid flow rates (i.e., 70% of selectivity for Pd-ZS with liquid 1 mL/min and gas 2.7 mL/min, liquid 0.5 mL/min MeOH and gas 4 mL/ min, and finally liquid 2 mL/min MeOH and gas 1 mL/min 65% of selectivity for Pd-CeS with liquid 1 mL/min and gas 4 mL/ min). Moreover, the same maximum production rate of H2O2 around 3 μmol/min for Pd-CeS, Pd-ZS, and Pd-Z was achieved with different liquid and gas flow rates. Continuous operation and reactor technology play important roles in this green synthesis: optimization of gas and liquid flow rates and contact time between the liquid and the solid (catalysts) phase lead to a dramatic selectivity improvement in a continuous reactor, raising the value obtained in the semibatch reactor from 30% to 70%. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26107443 [article] Direct synthesis of hydrogen peroxide in a trickle bed reactor : Comparison of Pd - based catalysts [texte imprimé] / Pierdomenico Biasi, Auteur ; Paolo Canu, Auteur ; Federica Menegazzo, Auteur . - 2012 . - pp. 8883-8890. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 26 (Juillet 2012) . - pp. 8883-8890 Mots-clés : Catalyst  Trickle  bed  reactor  Hydrogen  peroxide Résumé : Palladium catalysts based on different supports, silica (SiO2), zirconia (Z), sulfated ceria (CeS), and sulfated zirconia (ZS), previously tested in a semibatch reactor, were chosen to demonstrate how the direct synthesis process can be improved by continuous operation in a three-phase fixed bed. The gas and liquid flow rates were systematically varied to find suitable combinations for a maximum hydrogen peroxide production rate and selectivity. Different catalysts gave the same results in terms of selectivity and production rate with different operating conditions. A selectivity of 60% and 70% was found with two different catalysts (namely, Pd-ZS and Pd-CeS). Very interestingly those selectivities were found with different gas and liquid flow rates (i.e., 70% of selectivity for Pd-ZS with liquid 1 mL/min and gas 2.7 mL/min, liquid 0.5 mL/min MeOH and gas 4 mL/ min, and finally liquid 2 mL/min MeOH and gas 1 mL/min 65% of selectivity for Pd-CeS with liquid 1 mL/min and gas 4 mL/ min). Moreover, the same maximum production rate of H2O2 around 3 μmol/min for Pd-CeS, Pd-ZS, and Pd-Z was achieved with different liquid and gas flow rates. Continuous operation and reactor technology play important roles in this green synthesis: optimization of gas and liquid flow rates and contact time between the liquid and the solid (catalysts) phase lead to a dramatic selectivity improvement in a continuous reactor, raising the value obtained in the semibatch reactor from 30% to 70%. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26107443

Hydrogen peroxide direct synthesis / Pierdomenico Biasi in Industrial & engineering chemistry research, Vol. 49 N° 21 (Novembre 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 21 (Novembre 2010) . - pp. 10627-10632 Titre : Hydrogen peroxide direct synthesis : Selectivity enhancement in a trickle bed reactor Type de document : texte imprimé Auteurs : Pierdomenico Biasi, Auteur ; Federica Menegazzo, Auteur ; Francesco Pinna, Auteur Année de publication : 2011 Article en page(s) : pp. 10627-10632 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Trickle  bed  reactor  Hydrogen  peroxide Résumé : H2O2 direct synthesis over a palladium catalyst based on sulfated ceria (Pd-CeS) has been studied in a trickle-bed reactor at ― 10 °C. The combined effect of liquid and gas flow rates was studied by independent variations. The maximum productivity and selectivity was always found at flow rate combinations intermediate within the investigated range. The reactor operated under pressure and its effect was investigated (10 and 20 bar), resulting in a significant gain in selectivity. Selectivity up to 80% has been measured at the highest pressure tested (20 bars), liquid flow rate of 2 mL/min, and 6 mL/min gas flow rate. The maximum production rate measured was 0.0035 mmol/min with 0.5 mL/min liquid flow rate and 2.7 mL/min gas flow rate. Relevance of direct water formation has been isolated by independently investigating H2O2 decomposition and hydrogenation. Results indicate directions of further performance improvements and the importance of reactor type and operation. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=23447955 [article] Hydrogen peroxide direct synthesis : Selectivity enhancement in a trickle bed reactor [texte imprimé] / Pierdomenico Biasi, Auteur ; Federica Menegazzo, Auteur ; Francesco Pinna, Auteur . - 2011 . - pp. 10627-10632. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 21 (Novembre 2010) . - pp. 10627-10632 Mots-clés : Trickle  bed  reactor  Hydrogen  peroxide Résumé : H2O2 direct synthesis over a palladium catalyst based on sulfated ceria (Pd-CeS) has been studied in a trickle-bed reactor at ― 10 °C. The combined effect of liquid and gas flow rates was studied by independent variations. The maximum productivity and selectivity was always found at flow rate combinations intermediate within the investigated range. The reactor operated under pressure and its effect was investigated (10 and 20 bar), resulting in a significant gain in selectivity. Selectivity up to 80% has been measured at the highest pressure tested (20 bars), liquid flow rate of 2 mL/min, and 6 mL/min gas flow rate. The maximum production rate measured was 0.0035 mmol/min with 0.5 mL/min liquid flow rate and 2.7 mL/min gas flow rate. Relevance of direct water formation has been isolated by independently investigating H2O2 decomposition and hydrogenation. Results indicate directions of further performance improvements and the importance of reactor type and operation. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=23447955

Kinetics and mechanism of H2O2 direct synthesis over a Pd/C catalyst in a batch reactor / Pierdomenico Biasi in Industrial & engineering chemistry research, Vol. 51 N° 26 (Juillet 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 26 (Juillet 2012) . - pp. 8903–8912 Titre : Kinetics and mechanism of H2O2 direct synthesis over a Pd/C catalyst in a batch reactor Type de document : texte imprimé Auteurs : Pierdomenico Biasi, Auteur ; Nicola Gemo, Auteur ; José Rafael Hernández Carucci, Auteur Année de publication : 2012 Article en page(s) : pp. 8903–8912 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Kinetics  Catalyst Résumé : Kinetic experiments of the decomposition, hydrogenation, and direct synthesis of hydrogen peroxide were performed on a commercial Pd/C catalyst. Temperature effects and subsequent hydrogen addition were investigated without using promoters. The hydrogen amount in the liquid phase was measured online by using a Fugatron Instrument to investigate the effect of the gas on the direct synthesis. Decomposition and hydrogenation reactions were affected differently by the temperatures used during the experiments. The formation of hydrogen peroxide showed different behaviors with different hydrogen feeding policies. The hydrogen dissolved in the liquid phase measured experimentally was correlated with the hydrogen peroxide production. As the amount of dissolved hydrogen increases in the liquid phase the direct synthesis rate increases, while the reaction slows down as the hydrogen pressure is decreased. The selectivity is also affected by the H2 recharges. Every time that hydrogen is recharged in the reactor (during the direct synthesis) the selectivity toward H2O2 increases. Two different methods to recharge H2 during the reaction were analyzed. The first method consists in feeding the hydrogen when it is totally consumed, the second one in refilling hydrogen in the reactor before its total consumption. The hydrogen solubility was found as an important parameter for the direct synthesis. An explanation on hydrogen peroxide formation was given taking into account the H2/Pd ratio. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2021398 [article] Kinetics and mechanism of H2O2 direct synthesis over a Pd/C catalyst in a batch reactor [texte imprimé] / Pierdomenico Biasi, Auteur ; Nicola Gemo, Auteur ; José Rafael Hernández Carucci, Auteur . - 2012 . - pp. 8903–8912. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 26 (Juillet 2012) . - pp. 8903–8912 Mots-clés : Kinetics  Catalyst Résumé : Kinetic experiments of the decomposition, hydrogenation, and direct synthesis of hydrogen peroxide were performed on a commercial Pd/C catalyst. Temperature effects and subsequent hydrogen addition were investigated without using promoters. The hydrogen amount in the liquid phase was measured online by using a Fugatron Instrument to investigate the effect of the gas on the direct synthesis. Decomposition and hydrogenation reactions were affected differently by the temperatures used during the experiments. The formation of hydrogen peroxide showed different behaviors with different hydrogen feeding policies. The hydrogen dissolved in the liquid phase measured experimentally was correlated with the hydrogen peroxide production. As the amount of dissolved hydrogen increases in the liquid phase the direct synthesis rate increases, while the reaction slows down as the hydrogen pressure is decreased. The selectivity is also affected by the H2 recharges. Every time that hydrogen is recharged in the reactor (during the direct synthesis) the selectivity toward H2O2 increases. Two different methods to recharge H2 during the reaction were analyzed. The first method consists in feeding the hydrogen when it is totally consumed, the second one in refilling hydrogen in the reactor before its total consumption. The hydrogen solubility was found as an important parameter for the direct synthesis. An explanation on hydrogen peroxide formation was given taking into account the H2/Pd ratio. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2021398

Modeling of direct synthesis of hydrogen peroxide in a packed-bed reactor / Teuvo Kilpio in Industrial & engineering chemistry research, Vol. 51 N° 41 (Octobre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 41 (Octobre 2012) . - pp. 13366–13378 Titre : Modeling of direct synthesis of hydrogen peroxide in a packed-bed reactor Type de document : texte imprimé Auteurs : Teuvo Kilpio, Auteur ; Pierdomenico Biasi, Auteur ; Alice Bittante, Auteur Année de publication : 2012 Article en page(s) : pp. 13366–13378 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Hydrogen  peroxide Résumé : Direct synthesis of hydrogen peroxide from oxygen and hydrogen continues to be a research topic of high interest. It would be most desirable if this synthesis could be carried out in a continuous fixed-bed reactor in a safe way, with a catalyst providing both high selectivity and high productivity. This could significantly simplify the hydrogen peroxide production process and reduce both operating and investment costs. In the conventional anthraquinone-based production process, the hydrogenation and oxidation steps are carried out in separate reactors, and extraction is finally used for hydrogen peroxide recovery. Recirculation of large quantities of the multicomponent organic working solution takes place, and expensive filtration of the hydrogenation catalyst from this vast stream is required when a slurry reactor is used. The main benefit of the conventional process is that it is a well-proven and reliably operating technology. The most straightforward approach for the direct synthesis is to carry out the reaction between H2 and O2 on a heterogeneous catalyst, preferably Pd or Pd/Au catalyst, in a suitable solvent. Methanol is one of the most popular choices for the solvent because the solubilities of H2 and O2 in methanol are much larger than those in water. This article presents a modeling study for the direct synthesis of hydrogen peroxide with methanol as the solvent in a continuous three-phase reactor. The modeling study used data from an experimental study performed with a Pd/CeS catalyst in our laboratory reactor. The aim of the modeling was to provide insight into the physical and chemical phenomena occurring during the process. The reaction system was a challenging one, because both side reaction and decomposition reactions took place simultaneously with the highly desirable synthesis. The model was found to describe the experimental data from the fixed-bed reactor rather well. Particle diffusion was found to be most severe for the synthesis and oxidation reactions. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie301919y [article] Modeling of direct synthesis of hydrogen peroxide in a packed-bed reactor [texte imprimé] / Teuvo Kilpio, Auteur ; Pierdomenico Biasi, Auteur ; Alice Bittante, Auteur . - 2012 . - pp. 13366–13378. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 41 (Octobre 2012) . - pp. 13366–13378 Mots-clés : Hydrogen  peroxide Résumé : Direct synthesis of hydrogen peroxide from oxygen and hydrogen continues to be a research topic of high interest. It would be most desirable if this synthesis could be carried out in a continuous fixed-bed reactor in a safe way, with a catalyst providing both high selectivity and high productivity. This could significantly simplify the hydrogen peroxide production process and reduce both operating and investment costs. In the conventional anthraquinone-based production process, the hydrogenation and oxidation steps are carried out in separate reactors, and extraction is finally used for hydrogen peroxide recovery. Recirculation of large quantities of the multicomponent organic working solution takes place, and expensive filtration of the hydrogenation catalyst from this vast stream is required when a slurry reactor is used. The main benefit of the conventional process is that it is a well-proven and reliably operating technology. The most straightforward approach for the direct synthesis is to carry out the reaction between H2 and O2 on a heterogeneous catalyst, preferably Pd or Pd/Au catalyst, in a suitable solvent. Methanol is one of the most popular choices for the solvent because the solubilities of H2 and O2 in methanol are much larger than those in water. This article presents a modeling study for the direct synthesis of hydrogen peroxide with methanol as the solvent in a continuous three-phase reactor. The modeling study used data from an experimental study performed with a Pd/CeS catalyst in our laboratory reactor. The aim of the modeling was to provide insight into the physical and chemical phenomena occurring during the process. The reaction system was a challenging one, because both side reaction and decomposition reactions took place simultaneously with the highly desirable synthesis. The model was found to describe the experimental data from the fixed-bed reactor rather well. Particle diffusion was found to be most severe for the synthesis and oxidation reactions. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie301919y