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Toshio Suzuki - One of the best experts on this subject based on the ideXlab platform.
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palladium supported ionic liquid catalyst pd sh silc immobilized on mercaptopropyl silica gel as a chemoselective reusable and heterogeneous catalyst for catalytic hydrogenation
Green Chemistry, 2011Co-Authors: Hisahiro Hagiwara, Takashi Hoshi, Tomomi Nakamura, Toshio SuzukiAbstract:Palladium acetate was immobilized as Pd-SH-SILC (Pd-supported ionic liquid catalyst) in the pores of amorphous mercaptopropyl silica gel with the aid of an ionic liquid [bmim]BF4. The heterogeneous Pd-SH-SILC was effective for catalytic hydrogenation of a variety of olefins at atmospheric pressure and room temperature. It withstood recycling up to 10 times by Decantation.
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immobilization of grubbs catalyst as supported ionic liquid catalyst ru silc
Synlett, 2008Co-Authors: Hisahiro Hagiwara, Naotaro Okunaka, Takashi Hoshi, Toshio SuzukiAbstract:Grubbs olefin metathesis catalyst was immobilized as a ruthenium-supported ionic liquid catalyst (Ru-SILC) in pores of amorphous alumina with the aid of ionic liquid [hmim]PF 6 . This Ru-SILC was effective for various olefin metathesis reactions such as intra- or intermolecular macrocyclization and dimerization, and used up to six times after simple Decantation.
Ivana Maria Pereira - One of the best experts on this subject based on the ideXlab platform.
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Estudo de alguns parametros para precipitação de glicerol atraves de complexação com zinconio em vinhaças de alcool carburante e de aguardente e em lixivias fracas de sabvaria
[s.n.], 2018Co-Authors: Ivana Maria PereiraAbstract:Orientador: Roberto Herminio MorettiDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de AlimentosResumo: Neste trabalho avaliaram-se diferentes parâmetros, à nivel de laboratório, para precipitar glicerol de vinhaça mista da produção de álcool carburante e vinhaça de caIdo de cana da produção de aguardente, bem como de lixívias fracas de saboaria, através da complexação do glicerol com zircônio e posterior separação por centrifugação e decantação natural. Os processos utilizados consistiram do aquecimento dos efluentes (vinhaças "in natura" e pré-concentrada ou lixívias) com compostos de zircônio dando formação a uiït complexo glicerol-zircônio que precipita em meio alcalino. O precipitado foi então separado por centrifugação ou por decantação natural. Os precipitados após aquecimento a pH ácido liberam o glicerol, que pode então ser destilado. As variáveis estudadas foram: pH de precipitação do camplexo glicerol-zircônia; concentração de zircônio; compostos de zircônio (cloreto, nitrato e hidróxido); processo de separação de Precipitado e tempo de decantação natural. Os resultados mostraram que a pH 9.0 obteve-se a melhor precipitação do complexo glicerol-zircônio conseguindo-se uma maior concentração de glicerol no precipitado com menor perda de zircônio no sobrenadante para todos os efluentes empregados. A maior eficiência na concentração de glicerol foi obtida com hidróxido de zircônio para os dois processos de separação de precipitada e com todos os efluentes estudados, A decantação natural foi um processo de separação de precipitado melhor que a centrifugação quando utilizou-se hidróxido de zírcônio, tanto para as vinhaças quanto para a lixívia. O tempo ótimo de decantação foi de 3 horas. As concentrações ótimas de zircônio, quando foi empregado hidróxido e utilizando a decantação como processo de separação, foram de 1.6 %. (m/v) para vinhaça mista da produção de álcool carburante e vinhaça de aguardente. Para vinhaça mista pré-concentrada e lixívia fraca, esta concentração foi de 2.0% (m/v)Abstract: In this research, the different parameters involved in the precipitation of glycerol from fuel alcohol stillage (vinasse) distilled alcoholic liquor stillage and from a watery lye resulting from soap production, using complexing of the glycerol by zirconium and subsequent separation by centrifugation and by naturaI Decantation were evaluated. The process used consisted of heating those effluents (unconcentrated and pre-concentrated vinasse or lye) with zirconium compounds, thus forming a glycerol zirconium complex that precipitated in an alkaline medium. The precipitate separated by centrifugation or Decantation. After heating under acid conditions the precipitates released the glycerol, wich couId then be distilled. The variables studied were: pH for complex precipitation; zirconium concentration; zirconium compounds (chloride, nitrate and hydroxide); precipitate separation process and natural Decantation time. The resuIts showed that, with all the effluents studied, the optimum ph for the precipitation of the glycerol- zirconium cotmplex was 9.0 in order to obtain the highest glycerol concentration in the precipitate with lower loss o-f zirconium in the supernatant, In all cases the most efficient compound for glycerol concentration was zirconium hydroxide. Natural, Decantation was a better process for precipitate separation than centrifugation when the compound used was zirconium hydroxide both for stillages and for the watery lye. The optimum sedimentation time was three hours. The optimum zirconium concentration was 1,6% when using hydroxide zirconium and Decantation as the precipitate separation process for the unconcentrated sugar cane stillages resuIting from fuel alcohol production and resulting from distilled alcoholic liquor, and 2.0 % for the pre-concentrated sugar cane stillages resuIting from fuel alcohol production and for the watery lyeMestradoMestre em Tecnologia de Alimento
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Estudo de alguns parametros para precipitação de glicerol atraves de complexação com zinconio em vinhaças de alcool carburante e de aguardente e em lixivias fracas de sabvaria
2017Co-Authors: Ivana Maria PereiraAbstract:Resumo: Neste trabalho avaliaram-se diferentes parâmetros, à nivel de laboratório, para precipitar glicerol de vinhaça mista da produção de álcool carburante e vinhaça de caIdo de cana da produção de aguardente, bem como de lixívias fracas de saboaria, através da complexação do glicerol com zircônio e posterior separação por centrifugação e decantação natural. Os processos utilizados consistiram do aquecimento dos efluentes (vinhaças "in natura" e pré-concentrada ou lixívias) com compostos de zircônio dando formação a uiït complexo glicerol-zircônio que precipita em meio alcalino. O precipitado foi então separado por centrifugação ou por decantação natural. Os precipitados após aquecimento a pH ácido liberam o glicerol, que pode então ser destilado. As variáveis estudadas foram: pH de precipitação do camplexo glicerol-zircônia; concentração de zircônio; compostos de zircônio (cloreto, nitrato e hidróxido); processo de separação de Precipitado e tempo de decantação natural. Os resultados mostraram que a pH 9.0 obteve-se a melhor precipitação do complexo glicerol-zircônio conseguindo-se uma maior concentração de glicerol no precipitado com menor perda de zircônio no sobrenadante para todos os efluentes empregados. A maior eficiência na concentração de glicerol foi obtida com hidróxido de zircônio para os dois processos de separação de precipitada e com todos os efluentes estudados, A decantação natural foi um processo de separação de precipitado melhor que a centrifugação quando utilizou-se hidróxido de zírcônio, tanto para as vinhaças quanto para a lixívia. O tempo ótimo de decantação foi de 3 horas. As concentrações ótimas de zircônio, quando foi empregado hidróxido e utilizando a decantação como processo de separação, foram de 1.6 %. (m/v) para vinhaça mista da produção de álcool carburante e vinhaça de aguardente. Para vinhaça mista pré-concentrada e lixívia fraca, esta concentração foi de 2.0% (m/v).Abstract:In this research, the different parameters involved in the precipitation of glycerol from fuel alcohol stillage (vinasse) distilled alcoholic liquor stillage and from a watery lye resulting from soap production, using complexing of the glycerol by zirconium and subsequent separation by centrifugation and by naturaI Decantation were evaluated. The process used consisted of heating those effluents (unconcentrated and pre-concentrated vinasse or lye) with zirconium compounds, thus forming a glycerol zirconium complex that precipitated in an alkaline medium. The precipitate separated by centrifugation or Decantation. After heating under acid conditions the precipitates released the glycerol, wich couId then be distilled. The variables studied were: pH for complex precipitation; zirconium concentration; zirconium compounds (chloride, nitrate and hydroxide); precipitate separation process and natural Decantation time. The resuIts showed that, with all the effluents studied, the optimum ph for the precipitation of the glycerol- zirconium cotmplex was 9.0 in order to obtain the highest glycerol concentration in the precipitate with lower loss o-f zirconium in the supernatant, In all cases the most efficient compound for glycerol concentration was zirconium hydroxide. Natural, Decantation was a better process for precipitate separation than centrifugation when the compound used was zirconium hydroxide both for stillages and for the watery lye. The optimum sedimentation time was three hours. The optimum zirconium concentration was 1,6% when using hydroxide zirconium and Decantation as the precipitate separation process for the unconcentrated sugar cane stillages resuIting from fuel alcohol production and resulting from distilled alcoholic liquor, and 2.0 % for the pre-concentrated sugar cane stillages resuIting from fuel alcohol production and for the watery lye
Yan Zhang - One of the best experts on this subject based on the ideXlab platform.
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magnetic hydroxyapatite encapsulated γ fe2o3 nanoparticles functionalized with basic ionic liquids for aqueous knoevenagel condensation
Applied Catalysis A-general, 2009Co-Authors: Yan ZhangAbstract:Abstract Hydroxyapatite-encapsulated γ-Fe 2 O 3 nanoparticles functionalized with diethyl aliphatic amine basic ionic liquids were synthesized and used as efficient magnetic catalysts for aqueous Knoevenagel condensation reactions. Quantitative conversion of the reactants was achieved under mild conditions; recycle of the catalyst, through convenient magnetic Decantation, shows non-significant loss in activity. In comparison with the controlled experiments catalyzed by homogeneous basic ionic liquids and the basic ionic liquid-modified polystyrene resin, the excellent performance of the magnetic catalyst was attributed to the cooperativity between the base sites generated by framework HAP and the supported basic ionic liquids.
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basic ionic liquids supported on hydroxyapatite encapsulated γ fe2o3 nanocrystallites an efficient magnetic and recyclable heterogeneous catalyst for aqueous knoevenagel condensation
Journal of Molecular Catalysis A-chemical, 2009Co-Authors: Yan Zhang, Yingwei Zhao, Chungu XiaAbstract:A series of basic ionic liquids functionalized hydroxyapatite-encapsulated γ-Fe2O3 magnetic nanoparticles were synthesized and characterized by XRD, XPS, HRTEM, IR and BET. These magnetic nanoparticles were used as efficient heterogeneous catalysts for aqueous Knoevenagel condensation under mild conditions and excellent results for extended substrates were obtained. In comparison with the control experiments, the high activity is ascribed to the cooperativity between the base sites generated by framework hydroxyapatite and supported basic ionic liquids. Separation of the catalyst from the reaction mixture was readily achieved by simple magnetic Decantation and the catalyst could be easily recycled without appreciable loss of catalytic activity.
Hisahiro Hagiwara - One of the best experts on this subject based on the ideXlab platform.
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palladium supported ionic liquid catalyst pd sh silc immobilized on mercaptopropyl silica gel as a chemoselective reusable and heterogeneous catalyst for catalytic hydrogenation
Green Chemistry, 2011Co-Authors: Hisahiro Hagiwara, Takashi Hoshi, Tomomi Nakamura, Toshio SuzukiAbstract:Palladium acetate was immobilized as Pd-SH-SILC (Pd-supported ionic liquid catalyst) in the pores of amorphous mercaptopropyl silica gel with the aid of an ionic liquid [bmim]BF4. The heterogeneous Pd-SH-SILC was effective for catalytic hydrogenation of a variety of olefins at atmospheric pressure and room temperature. It withstood recycling up to 10 times by Decantation.
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immobilization of grubbs catalyst as supported ionic liquid catalyst ru silc
Synlett, 2008Co-Authors: Hisahiro Hagiwara, Naotaro Okunaka, Takashi Hoshi, Toshio SuzukiAbstract:Grubbs olefin metathesis catalyst was immobilized as a ruthenium-supported ionic liquid catalyst (Ru-SILC) in pores of amorphous alumina with the aid of ionic liquid [hmim]PF 6 . This Ru-SILC was effective for various olefin metathesis reactions such as intra- or intermolecular macrocyclization and dimerization, and used up to six times after simple Decantation.
Jeanluc Bertrandkrajewski - One of the best experts on this subject based on the ideXlab platform.
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modelisation numerique 3d de la Decantation et de la remise en suspension des polluants particulaires en regime transitoire dans un bassin de retenue Decantation des eaux pluviales
Houille Blanche-revue Internationale De L Eau, 2013Co-Authors: Hexiang Yan, Gislain Lipeme Kouyi, Jeanluc BertrandkrajewskiAbstract:Les bassins de retenue des eaux pluviales peuvent etre utilises pour controler les polluants particulaires des rejets urbains par temps de pluie. Pour ameliorer leur fonctionnement, il est indispensable de maitriser et mieux modeliser les phenomenes lies au transport des particules (Decantation, remise en suspension, dispersion). En general, le debit et les rejets polluants varient en fonction du temps au cours des evenements pluvieux. Cependant, la majorite des etudes faisant appel a la CFD pour simuler le transport particulaire dans les bassins de Decantation n'a pas accorde suffisamment d'attention a l'effet des variations temporelles sur les mecanismes de transport. Cet article presente une nouvelle demarche de modelisation du transport particulaire a l'aide de l'approche Euler-Lagrange afin de prendre en compte la remise en suspension en conditions transitoires. Pour ce faire, plusieurs conditions limites au fond ont ete developpees et implementees dans un code de calcul afin de representer l'interaction entre les particules et le fond du bassin. La comparaison des resultats des simulations avec les donnees experimentales sur l'efficacite de Decantation et les zones de depot montre que les conditions de type BTKE et BSS estimees a partir des caracteristiques des particules sont satisfaisantes.
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modelisation numerique 3d des ecoulements turbulents a surface libre charges en polluants particulaires dans un bassin de retenue Decantation des eaux pluviales
Houille Blanche-revue Internationale De L Eau, 2011Co-Authors: Hexiang Yan, Gislain Lipeme Kouyi, Jeanluc BertrandkrajewskiAbstract:Une fraction importante des charges polluantes des eaux pluviales est fixee sur les particules solides souvent vehiculees en suspension et qui decantent facilement lorsque les conditions hydrodynamiques le permettent (faible vitesse d’ecoulement en general). C’est pourquoi la connaissance du transport solide et de la Decantation est indispensable a la conception et a la gestion d’un bassin. Une nouvelle methode permettant de simuler les processus de Decantation est presentee dans cet article. Elle est fondee sur la comparaison de l’energie transportee par la particule lorsqu’elle decante a l’energie cinetique turbulente pres du fond. L’energie liee a la particule qui decante est calculee a partir de sa vitesse de chute. Sur cette base, un programme a ete developpe et integre dans le logiciel Ansys Fluent. Le modele developpe a ensuite ete teste dans le but d’identifier les zones preferentielles de depot dans un bassin pilote. Les resultats obtenus montrent que les zones de depot observees et simulees sont similaires. Cette methode permet de prendre en compte simultanement les caracteristiques de la particule (principalement la vitesse de chute) et celles de l’ecoulement pres du fond (en particulier l’energie cinetique turbulente).
