Kinetics of Alkali Isomerization of Linoleic Acid from Walnut Oil Converted into Conjugation of Linoleic Acid

Abstract:

Conjugated linoleic acid (CLA) was prepared by alkali isomerization using walnut oil as raw materials, KOH as catalyst and propylene glycol as solvent. The kinetics of alkali isomerization of linoleic acid from walnut oil converted into CLA was experimentally studied under the reaction conditions of 393~453 K,and which the initial mass ratio of propylene glycol, walnut oil and KOH was 3:2:1. The mechanism of alkali isomerization was proposed, and the mechanism model was put forward through theoretical derivation.The rate constants were determined, the mechanism model was verified,and the kinetics parameters were obtained.The results showed that alkali isomerization reaction was first order the concentration of linoleic acid, which the apparent activation energy was 67.22 kJ·mol^-1 and the pre-exponential constant was 8.963×10⁵min^-1.

• Periodical: Advanced Materials Research (Volume 773)
• Pages: 316-321
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.773.316
• Online since: September 2013
• Authors: Xiang Feng Xiong, Chao Yin Chen, Sheng Lan Zhao, Ben Yong Han
• Keywords: Alkali Isomerization, Conjugated Linoleic Acid, Kinetic, Rate Constant

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