Kevin R. Heier

Bio: Kevin R. Heier is an academic researcher. The author has contributed to research in topics: Catalysis & Soybean oil. The author has an hindex of 1, co-authored 1 publications receiving 53 citations.

Kinetics, Gas−Liquid Mass Transfer, and Modeling of the Soybean Oil Hydrogenation Process

Abstract: The kinetics for soybean oil hydrogenation using a commercial Ni/Al2O3 catalyst were investigated in a 2 × 10-3 m3 agitated reaction calorimeter operating under a wide range of temperatures (383−44...

Three-phase hydrogenation of d-glucose over a carbon supported ruthenium catalyst—mass transfer and kinetics

Abstract: The catalytic hydrogenation of d -glucose to d -sorbitol over a 5% Ru/C catalyst was studied in a semi-batch slurry autoclave operating at 373–403 K and 4.0–7.5 MPa hydrogen pressure. The d -glucose concentration was varied between 0.56 and 1.39 mol/l. The kinetic experiments were carried out in the absence of mass transport limitations, which was verified by using measured gas–liquid mass transfer coefficients and estimated diffusion and liquid–solid mass transfer coefficients. Many literature reports suffer from transport limitations. In the operating regime studied the reaction rate showed a first order dependency with respect to hydrogen. A shift in the order of d -glucose was observed. At low d -glucose concentrations (up to ca. 0.3 mol/l) the reaction showed a first order dependency, while at higher concentrations this changed to zero order behavior. No inhibition by sorbitol or mannitol was observed. The kinetic data were modeled using three plausible rate models based on Langmuir–Hinshelwood–Hougen–Watson (LHHW) kinetics assuming that the surface reaction is rate-determining. Model 1 involves non-competitive adsorption of hydrogen and d -glucose. Hydrogen adsorption is either molecular or dissociative, but due to the weak adsorption it results in both cases in a linear hydrogen pressure dependency, i.e. the same rate expression; Model 2 is based on competitive adsorption of molecular hydrogen and d -glucose; and Model 3 assumes competitive adsorption of dissociatively chemisorbed hydrogen and d -glucose. All three models described the data satisfactorily and further statistic discrimination between these models was not possible.

Monolithic Catalysts as an Alternative to Slurry Systems: Hydrogenation of Edible Oil

Abstract: The use of monolithic catalysts in multiphase applications has received increasing interest throughout the last years. In this paper the use of monolithic catalysts in the hydrogenation of edible oils is studied. In comparative experiments the monolithic catalysts have shown a lower tendency to form trans-fatty acids compared to slurry catalysts with equal composition. It is also demonstrated that the monolithic catalyst could be reused several times without significant changes in the product composition. With respect to the effect of the operating parameters on the performance, common knowledge applies. By using a monolithic-catalyst-based technology, the process complexity can be significantly reduced as the separation of the oil and the catalyst becomes straightforward and the filtration and bleach steps are eliminated. An economic evaluation showed a significant reduction in the product cost when monoliths are used instead of a conventional slurry system.

Low trans-fatty acid fat compositions; low-temperature hydrogenation, e.g., of edible oils

Abstract: The present disclosure provides low trans-fatty acid fat compositions, methods of hydrogenating unsaturated feedstocks (e.g., oils), and hydrogenation catalyst compositions. One exemplary method involves producing a catalyst composition by heating a nickel-based catalyst to a first temperature of at least about 85° C in the presence of hydrogen and a fat component. An unsaturated feedstock may be contacted with the catalyst composition and hydrogenated by sustaining a hydrogenation reaction at a second temperature of no greater than about 700 C. Some specific implementations of the invention permit the production of partially hydrogenated seed oils with low trans-fatty acid contents.