Soybean oil has been partially hydrogenated in the presence of a synthesized nickel catalyst, in an industrial reactor, under the standard industrial working conditions. The GC measurements of fatty acids in the investigated oil and hydrogenated products have been performed. The total trans isomers content has been determined by the LR spectroscopy. The model is established, which could be useful for the characterization of hydrogenation and isomerization reactions of poly-unsaturated acids. Iteration procedure, incorporating numerical simulation in each step is used to calculate rate constants of the proposed model from the comparison of the experimental and calculated kinetic runs. By the simultaneous treatment of the kinetic runs for the fatty acids composition and trans-isomer content, the 12 rate constants of individual hydrogenation and isomerization reaction steps are obtained.