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Catalytic hydrogenolysis of glycerol to propylene glycol over mixed oxides derived from a hydrotalcite-type precursor / Lekha Charan Meher in Industrial & engineering chemistry research, Vol. 48 N°4 (Février 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N°4 (Février 2009) . - pp. 1840–1846 Titre : Catalytic hydrogenolysis of glycerol to propylene glycol over mixed oxides derived from a hydrotalcite-type precursor Type de document : texte imprimé Auteurs : Lekha Charan Meher, Auteur ; Rajesh Gopinath, Auteur ; S. N. Naik, Auteur Année de publication : 2009 Article en page(s) : pp. 1840–1846 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Propylene  glycol  Glycerol  Hydrogenolysis  Cu/Zn/Al  mixed-metal  oxide  catalysts Résumé : Selective hydrogenolysis of glycerol to propylene glycol was performed using an environmentally friendly hydrotalcite-derived mixed-metal oxide catalyst. The Mg/Al, Zn/Al, Ni/Mg/Al, Ni/Co/Mg/Al, and Cu/Zn/Al mixed-metal oxide catalysts were prepared from their corresponding hydrotalcite precursors having M2+/M3+ compositions over the range of 0.5−3.0. The physicochemical properties of the catalysts were studied by X-ray diffraction (XRD), inductively coupled plasma mass spectrometry (ICP-MS), NH3 and CO2 temperature-programmed desorption (TPD), and nitrogen adsorption studies. The XRD patterns of pure hydrotalcites exhibited characteristics of hydrotalcite phases, while those of calcined hydrotalcites showed the formation of corresponding metal oxides. The ICP-MS analysis showed agreement between the calculated and actual metal compositions. The prepared catalysts were evaluated for the hydrogenolysis of glycerol to propylene glycol in a Parr reactor. The activity studies indicated a maximum glycerol conversion and selectivity toward propylene glycol in the case of Cu/Zn/Al mixed-metal oxide catalysts. Further, the reaction parameters were optimized with the most active Cu/Zn/Al catalyst, and it was found that at a catalyst concentration of 5% (w/w) of aqueous glycerol, a hydrogen pressure of 200 psig, and 80% glycerol dilution, a maximum glycerol conversion of 52% with 93−94% selectivity toward propylene glycol were obtained. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8011424 [article] Catalytic hydrogenolysis of glycerol to propylene glycol over mixed oxides derived from a hydrotalcite-type precursor [texte imprimé] / Lekha Charan Meher, Auteur ; Rajesh Gopinath, Auteur ; S. N. Naik, Auteur . - 2009 . - pp. 1840–1846. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N°4 (Février 2009) . - pp. 1840–1846 Mots-clés : Propylene  glycol  Glycerol  Hydrogenolysis  Cu/Zn/Al  mixed-metal  oxide  catalysts Résumé : Selective hydrogenolysis of glycerol to propylene glycol was performed using an environmentally friendly hydrotalcite-derived mixed-metal oxide catalyst. The Mg/Al, Zn/Al, Ni/Mg/Al, Ni/Co/Mg/Al, and Cu/Zn/Al mixed-metal oxide catalysts were prepared from their corresponding hydrotalcite precursors having M2+/M3+ compositions over the range of 0.5−3.0. The physicochemical properties of the catalysts were studied by X-ray diffraction (XRD), inductively coupled plasma mass spectrometry (ICP-MS), NH3 and CO2 temperature-programmed desorption (TPD), and nitrogen adsorption studies. The XRD patterns of pure hydrotalcites exhibited characteristics of hydrotalcite phases, while those of calcined hydrotalcites showed the formation of corresponding metal oxides. The ICP-MS analysis showed agreement between the calculated and actual metal compositions. The prepared catalysts were evaluated for the hydrogenolysis of glycerol to propylene glycol in a Parr reactor. The activity studies indicated a maximum glycerol conversion and selectivity toward propylene glycol in the case of Cu/Zn/Al mixed-metal oxide catalysts. Further, the reaction parameters were optimized with the most active Cu/Zn/Al catalyst, and it was found that at a catalyst concentration of 5% (w/w) of aqueous glycerol, a hydrogen pressure of 200 psig, and 80% glycerol dilution, a maximum glycerol conversion of 52% with 93−94% selectivity toward propylene glycol were obtained. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8011424

Composition of absolutes of jasminum sambac L. flowers fractionated with liquid CO2 and methanol and comparison with liquid CO2 extract / P. K. Rout in The journal of essential oil research, Vol. 22 N° 5 (Septembre/Octobre 2010) 

Public ISBD [article]  in The journal of essential oil research > Vol. 22 N° 5 (Septembre/Octobre 2010) . - pp. 398-406 Titre : Composition of absolutes of jasminum sambac L. flowers fractionated with liquid CO2 and methanol and comparison with liquid CO2 extract Type de document : texte imprimé Auteurs : P. K. Rout, Auteur ; S. N. Naik, Auteur ; Y. R. Rao, Auteur Année de publication : 2011 Article en page(s) : pp. 398-406 Note générale : Génie Chimique Langues : Anglais (eng) Mots-clés : Jasminum  sambac  Oleaceae  Liquid  CO2  fractionation  Liquid  CO2  extract  Concrete  composition  Absolute  composition  Linalool  Benzyl  acetate  (E,E)-α-farnesene  (Z)-3-hexenyl  benzoate Index. décimale : 646 Résumé : Absolutes obtained by fractionation of the pentane extract (concrete) of flowers of Jasminum sambac L. with cold methanol or liquid CO2 were compared. Direct extraction of flowers with liquid CO2 gave a relatively fat-free and superior product in 0.44% yield. It was found that the CO2 method of fractionation of pentane extract is a practical process providing an organoleptically superior product, though the product is not totally free from waxy substances. (E,E)-α-Farnesene and (Z)-3-hexenyl benzoate, along with compounds like indole, methyl anthranilate and methyl jasmonate, responsible for high diffusivity of the jasmine fragrance, have been obtained with improved recoveries in the CO2 fractionated concrete. DEWEY : 665 ISSN : 1041-2905 En ligne : http://www.tandfonline.com/doi/abs/10.1080/10412905.2010.9700356 [article] Composition of absolutes of jasminum sambac L. flowers fractionated with liquid CO2 and methanol and comparison with liquid CO2 extract [texte imprimé] / P. K. Rout, Auteur ; S. N. Naik, Auteur ; Y. R. Rao, Auteur . - 2011 . - pp. 398-406. Génie Chimique Langues : Anglais (eng) in The journal of essential oil research > Vol. 22 N° 5 (Septembre/Octobre 2010) . - pp. 398-406 Mots-clés : Jasminum  sambac  Oleaceae  Liquid  CO2  fractionation  Liquid  CO2  extract  Concrete  composition  Absolute  composition  Linalool  Benzyl  acetate  (E,E)-α-farnesene  (Z)-3-hexenyl  benzoate Index. décimale : 646 Résumé : Absolutes obtained by fractionation of the pentane extract (concrete) of flowers of Jasminum sambac L. with cold methanol or liquid CO2 were compared. Direct extraction of flowers with liquid CO2 gave a relatively fat-free and superior product in 0.44% yield. It was found that the CO2 method of fractionation of pentane extract is a practical process providing an organoleptically superior product, though the product is not totally free from waxy substances. (E,E)-α-Farnesene and (Z)-3-hexenyl benzoate, along with compounds like indole, methyl anthranilate and methyl jasmonate, responsible for high diffusivity of the jasmine fragrance, have been obtained with improved recoveries in the CO2 fractionated concrete. DEWEY : 665 ISSN : 1041-2905 En ligne : http://www.tandfonline.com/doi/abs/10.1080/10412905.2010.9700356

Composition of essential oils of tagetes patula L. growing in northern India / D. Vidya Sagar in The journal of essential oil research, Vol. 17 N° 4 (Juillet-Août 2005) 

Public ISBD [article]  in The journal of essential oil research > Vol. 17 N° 4 (Juillet-Août 2005) . - pp. 446-448 Titre : Composition of essential oils of tagetes patula L. growing in northern India Type de document : texte imprimé Auteurs : D. Vidya Sagar, Auteur ; S. N. Naik, Auteur ; P. K. Rout, Auteur Année de publication : 2006 Article en page(s) : pp. 446-448 Note générale : Génie Chimique Langues : Anglais (eng) Mots-clés : Tagetes  patula  Asteraceae  Essential  oil  composition  Limonene  (Z)-β-ocimene  Dihydrotagetone  Terpinolene  p-cymen-8-ol  Piperitone  Trans-sesquisabinene  hydrate Résumé : The chemical compositions of the essential oils of Tagetes patula leaf, capitula and total above ground herb collected from Farrukhnagar (28°N, 76°E), Haryana, India were subjected to analysis by GC and GC/MS. The major constituents of the oils were limonene (6.2–13.6%), (Z)-(3-ocimene (0.3–8.3%), dihydrotagetone (4.5–8.1%), terpinolene (0–11.2%), p-cymen-8-ol (3.4–11.0%), piperitone (6.1–11.9%), piperitenone (2.7–8.1%), β-caryophyllene (2.3–8.0%) and trans-sesquisabinene hydrate (2.0–12.5%). ISSN : 1041-2905 En ligne : http://www.tandfonline.com/doi/abs/10.1080/10412905.2005.9698958#.UeJfvWF2_n4 [article] Composition of essential oils of tagetes patula L. growing in northern India [texte imprimé] / D. Vidya Sagar, Auteur ; S. N. Naik, Auteur ; P. K. Rout, Auteur . - 2006 . - pp. 446-448. Génie Chimique Langues : Anglais (eng) in The journal of essential oil research > Vol. 17 N° 4 (Juillet-Août 2005) . - pp. 446-448 Mots-clés : Tagetes  patula  Asteraceae  Essential  oil  composition  Limonene  (Z)-β-ocimene  Dihydrotagetone  Terpinolene  p-cymen-8-ol  Piperitone  Trans-sesquisabinene  hydrate Résumé : The chemical compositions of the essential oils of Tagetes patula leaf, capitula and total above ground herb collected from Farrukhnagar (28°N, 76°E), Haryana, India were subjected to analysis by GC and GC/MS. The major constituents of the oils were limonene (6.2–13.6%), (Z)-(3-ocimene (0.3–8.3%), dihydrotagetone (4.5–8.1%), terpinolene (0–11.2%), p-cymen-8-ol (3.4–11.0%), piperitone (6.1–11.9%), piperitenone (2.7–8.1%), β-caryophyllene (2.3–8.0%) and trans-sesquisabinene hydrate (2.0–12.5%). ISSN : 1041-2905 En ligne : http://www.tandfonline.com/doi/abs/10.1080/10412905.2005.9698958#.UeJfvWF2_n4