Buan, South Korea
Buan, South Korea

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Kim D.W.,Pukyong National University | Ha S.H.,Pukyong National University | Moon M.J.,Pukyong National University | Lim K.T.,Pukyong National University | And 4 more authors.
Journal of Nanoscience and Nanotechnology | Year: 2015

Cu-Zn-Al catalysts were prepared using microwave-assisted process and co-precipitation methods. The prepared catalysts were characterized by XRD, BET, XPS and TPD of ammonia and their catalytic activity for the hydrogenolysis of glycerol to propylene glycol was also examined. The XRD patterns of Cu/Zn/Al mixed catalysts show CuO and ZnO crystalline phase regardless of preparation method. The highest glycerol hydrogenolysis conversion is obtained with the catalyst having a Cu/Zn/Al ratio of 2:2:1. Hydrogen pre-reduction of catalysts significantly enhanced both glycerol conversions and selectivity to propylene glycol. The glycerol conversion increased with an increase of reaction temperature. However, the selectivity to propylene glycol increased with an increase of temperature, and then declined to 30.5% at 523 K. Copyright © 2015 American Scientific Publishers All rights reserved.

Lee S.-D.,Zeus Oil and Chemicals Co. | Kim B.-M.,Pusan National University | Kim D.-W.,Pusan National University | Kim M.-I.,Pusan National University | And 4 more authors.
Applied Catalysis A: General | Year: 2014

Polystyrene-supported quaternized ammonium salt catalysts (PS-alkyl-AX) were synthesized and characterized by various physicochemical analytic methods such as EA, FT-IR, XPS, and SEM. The reactivity of the catalysts was investigated for the synthesis of allyl glycidyl carbonate from CO2 and allyl glycidyl ether under mild reaction conditions. The PS-alkyl-AX catalysts showed good catalytic activity without using any solvent due to the synergistic effect of NH functional group and quaternary ammonium salt structure. Theoretical studies using density functional theory (DFT) was applied to investigate the reaction mechanism. The PS-hexyl-MeI catalyst was readily recoverable and reusable in subsequent reaction cycles without a significant loss in its activity. © 2014 Elsevier B.V. All rights reserved.

Kim D.-W.,Pusan National University | Park M.-S.,Pusan National University | Selvaraj M.,Pusan National University | Park G.-A.,Pusan National University | And 2 more authors.
Research on Chemical Intermediates | Year: 2011

Ionic liquids (ILs) immobilized onto a structurally modified Merrifield peptide resin (MPR) were prepared through the reaction of imidazole with alkoxylated MPR. Elemental analysis and scanning electron microscopy (SEM) observations showed that the immobilized IL groups were effectively incorporated on the support. The MPR-supported ILs (MPR-ILs) proved to be effective heterogeneous catalysts for the synthesis of glycerol carbonate (GC) from glycerol and urea. MPR-ILs with longer alkyl chain linkers and fewer sterically hindered counteranions resulted in higher conversion of glycerol. High temperature, high degree of vacuum and the presence of zinc oxide co-catalyst were favorable for glycerol conversion. The MPR-ILs could be reused in up to three consecutive runs without significant loss of their catalytic activity. © 2011 Springer Science+Business Media B.V.

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