TY - JOUR
T1 - Isomerization of linoleic acid over supported metal catalysts
AU - Bernas, Andreas
AU - Kumar, Narendra
AU - Mäki-Arvela, Päivi
AU - Kul'kova, Natalya V.
AU - Holmbom, Bjarne
AU - Salmi, Tapio
AU - Murzin, Dmitry Yu
N1 - Funding Information:
This work is part of the activities at the Åbo Akademi Process Chemistry Group within the Finnish Centre of Excellence Programme (2000–2005) by the Academy of Finland. Financial support from the Raisio Group Research Foundation is gratefully acknowledged. The authors express their gratitude to Markku Reunanen for his contribution to the GC–MS analyses.
Copyright:
Copyright 2004 Elsevier Science B.V., Amsterdam. All rights reserved.
PY - 2003/6/10
Y1 - 2003/6/10
N2 - Heterogeneous supported metal catalysts were applied for the isomerization reaction of linoleic acid (cis-9,cis-12-octadecadienoic acid) to conjugated linoleic acid (CLA) between 80 and 120°C in a diluted system. Ru, Ni, Pd, Pt, Rh, Ir, Os, and bimetallic Pt-Rh supported by activated carbon, Al2O3, SiO2Al2O3, MCM-22, H-MCM-41, H-Y, and H-β were screened. Catalyst characterization was done by XRD, X-ray fluorescence, XPS, H2-TPD, DCP-AES, and nitrogen adsorption techniques. The isomerization reaction was conducted batchwise in both 1-octanol and n-decane as solvents. Reactions taking place were the isomerization of linoleic acid to CLA, hydrogenation of linoleic acid and CLA to monounsaturated octadecenoic acids (oleic acid, elaidic acid, cis-vaccenic acid, and trans-vaccenic acid), as well as the further hydrogenation of monounsaturated acids to stearic acid (n-octadecanoic acid) with isomerization and hydrogenation being two competing parallel reactions. The isomerization reaction was enhanced by catalyst preactivation under hydrogen. The presence of chemisorbed hydrogen increased the conversion but reduced the isomerization selectivity. Ru and Ni showed the best isomerization properties whereas Pd favored the double bond hydrogenation reaction.
AB - Heterogeneous supported metal catalysts were applied for the isomerization reaction of linoleic acid (cis-9,cis-12-octadecadienoic acid) to conjugated linoleic acid (CLA) between 80 and 120°C in a diluted system. Ru, Ni, Pd, Pt, Rh, Ir, Os, and bimetallic Pt-Rh supported by activated carbon, Al2O3, SiO2Al2O3, MCM-22, H-MCM-41, H-Y, and H-β were screened. Catalyst characterization was done by XRD, X-ray fluorescence, XPS, H2-TPD, DCP-AES, and nitrogen adsorption techniques. The isomerization reaction was conducted batchwise in both 1-octanol and n-decane as solvents. Reactions taking place were the isomerization of linoleic acid to CLA, hydrogenation of linoleic acid and CLA to monounsaturated octadecenoic acids (oleic acid, elaidic acid, cis-vaccenic acid, and trans-vaccenic acid), as well as the further hydrogenation of monounsaturated acids to stearic acid (n-octadecanoic acid) with isomerization and hydrogenation being two competing parallel reactions. The isomerization reaction was enhanced by catalyst preactivation under hydrogen. The presence of chemisorbed hydrogen increased the conversion but reduced the isomerization selectivity. Ru and Ni showed the best isomerization properties whereas Pd favored the double bond hydrogenation reaction.
KW - Conjugated linoleic acid (CLA)
KW - Double bond migration
KW - Functional food
KW - Hydrogenation
KW - Isomerization
KW - Linoleic acid
KW - Supported metal catalysts
UR - http://www.scopus.com/inward/record.url?scp=0037809698&partnerID=8YFLogxK
U2 - 10.1016/S0926-860X(02)00646-4
DO - 10.1016/S0926-860X(02)00646-4
M3 - Article
AN - SCOPUS:0037809698
SN - 0926-860X
VL - 245
SP - 257
EP - 275
JO - Applied Catalysis A: General
JF - Applied Catalysis A: General
IS - 2
ER -