Catalytic Hydrodeoxygenation of Fatty Acids for Biodiesel Production

This paper is devoted to the production of second generation biodiesel via catalytic hydrodeoxygenation of fatty acids. Pd/C catalysts with different metal loading were used. The palladium catalysts were characterized using low-temperature nitrogen physisorption and X-ray photoelectron spectroscopy. It was revealed that the most active and selective catalyst was 1%-Pd/C which allowed reaching up 97.5% of selectivity (regarding to n-heptadecane) at 100% conversion of substrate. Moreover, the chosen catalyst is more preferable according to lower metal content that leads the decrease of the process cost. The analysis of the catalysts showed that 1%-Pd/C had the highest specific surface area compared with 5%-Pd/C. Copyright © 2016 BCREC GROUP. All rights reservedReceived: 31st July 2015; Revised: 9th December 2015; Accepted: 30th December 2015How to Cite: Stepacheva, A.A., Sapunov, V.N., Sulman, E.M., Nikoshvili, L.Z., Sulman, M.G., Sidorov, A.I., Demidenko, G.N., Matveeva, V.G. (2016). Catalytic Hydrodeoxygenation of Fatty Acids for Biodiesel Production. Bulletin of Chemical Reaction Engineering & Catalysis, 11 (2): 125-132 (doi:10.9767/bcrec.11.2.538.125-132)Permalink/DOI: http://dx.doi.org/10.9767/bcrec.11.2.538.125-132Article Metrics: (click on the button below to see citations in Scopus)

Metal oxide–zeolite composites in transformation of methanol to hydrocarbons : do iron oxide and nickel oxide matter?

The methanol-to-hydrocarbon (MTH) reaction has received considerable attention as utilizing renewable sources of both value-added chemicals and fuels becomes a number one priority for society. Here, for the first time we report the development of hierarchical zeolites (ZSM-5) containing both iron oxide and nickel oxide nanoparticles. By modifying the iron oxide (magnetite, Fe3O4) amounts, we are able to control the catalyst activity and the product distribution in the MTH process. At the medium Fe3O4 loading, the major fraction is composed of C9–C11 hydrocarbons (gasoline fraction). At the higher Fe3O4 loading, C1–C4 hydrocarbons prevail in the reaction mixture, while at the lowest magnetite loading the major component is the C5–C8 hydrocarbons. Addition of Ni species to Fe3O4–ZSM-5 leads to the formation of mixed Ni oxides (NiO/Ni2O3) positioned either on top of or next to Fe3O4 nanoparticles. This modification allowed us to significantly improve the catalyst stability due to diminishing coke formation and disordering of the coke formed. The incorporation of Ni oxide species also leads to a higher catalyst activity (up to 9.3 g(methanol)/(g(ZSM-5) × h)) and an improved selectivity (11.3% of the C5–C8 hydrocarbons and 23.6% of the C9–C11 hydrocarbons), making these zeolites highly promising for industrial applications

Promotion Effect of Alkali Metal Hydroxides on Polymer-Stabilized Pd Nanoparticles for Selective Hydrogenation of C–C Triple Bonds in Alkynols

Postimpregnation of Pd nanoparticles (NPs) stabilized within hyper-cross-linked polystyrene with sodium or potassium hydroxides of optimal concentration was found to significantly increase the catalytic activity for the partial hydrogenation of the C–C triple bond in 2-methyl-3-butyn-2-ol at ambient hydrogen pressure. The alkali metal hydroxide accelerates the transformation of the residual Pd(II) salt into Pd(0) NPs and diminishes the reaction induction period. In addition, the selectivity to the desired 2-methyl-3-buten-2-ol increases with the K- and Na-doped catalysts from 97.0 up to 99.5%. This effect was assigned to interactions of the alkali metal ions with the Pd NPs surfaces resulting in the sites’ separation and a change of reactants adsorption

Pd-Nanoparticles Confined Within Hollow Polymeric Framework as Effective Catalysts for the Synthesis of Fine Chemicals

Encapsulation of metal nanoclusters in porous solid polymer materials is a promising approach to combine the outstanding properties of both, heterogeneous and homogeneous catalysts. We report heterogeneous nano-engineered catalysts containing Pd-nanoparticles (NPs) confined within highly-porous hollow polymeric framework of hyper cross-linked polystyrene (HPS). HPS with different surface functionalities (amine vs. sulfonate) were used for impregnation by Pd precursors of different nature and followed by a variety of catalyst post-treatments. The catalysts have been tested in two model key reactions for the synthesis of fine chemicals: selective hydrogenation of 2-methyl-3-butyne-2-ol to 2-methyl-3-butene-2-ol (MBE) and Suzuki cross-coupling of 4-bromoanisole with phenylboronic acid. Optimization of the Pd/HPS preparation and reaction conditions allowed attaining high selectivity (similar to 99 %) to target MBE at close to full conversion. For Suzuki cross-coupling more than 90 % yield of coupling product was obtained under mild reaction conditions and the absence of phase transfer agent. Our results demonstrate the potential of HPS as a suitable support for tailoring metal NPs properties and circumvent undesirable metal leaching

Immobilized glucose oxidase on magnetic silica and alumina: Beyond magnetic separation

Here we report immobilization of glucose oxidase (GOx) on magnetic silica (Fe3O4-SiO2) and alumina (Fe3O4-Al2O3) functionalized with amino groups using glutaraldehyde as a linker. Magnetic support based biocatalysts demonstrate high catalytic activity in d-glucose oxidation to D-gluconic acid at pH 5–7.5 and temperature of 30–50 °C with the best activities of 95% and 91% for magnetic silica and alumina, respectively. A comparison of magnetic and non-magnetic alumina and silica shows a significant enhancement of the relative catalytic activity for magnetic supports, while the silica based biocatalysts show a higher activity than the biocatalysts based on alumina. A noticeably higher activity of GOx immobilized on magnetic supports is explained by synergy of the GOx inherent activity and enzyme-like activity of iron oxide nanoparticles, while the enhancement with silica based catalysts is most likely due to a larger pore size and stronger Brønsted acid sites. Excellent relative activity of Fe3O4-SiO2-GOx (95% of native GOx) in a tolerant pH and temperature range as well as high stability in a repeated use (6% relative activity loss after five catalytic cycles) makes this catalyst promising for practical applications

Effect of Metal Chlorides on the Pyrolysis of Wheat Straw

In this paper, the results of the study on the influence of the addition of 10 wt.% of FeCl3, CoCl2, NiCl2, ZnCl2, SnCl2, and CuCl2 on the wheat straw pyrolysis process are presented. The studied chlorides were found to affect the pyrolysis process; however, the highest activity was observed while using CuCl2. The presence of the copper chloride led to the decrease in the temperature of the initial destruction of hemicellulose fraction of wheat straw by 64°С. Besides, the use of CuCl2 allowed increasing the yield of liquid and solid pyrolysis products as well as decreasing the molecular weight distribution of the volatiles. Moreover, the increase in the hydrogen and decrease in carbon dioxide concentration were also observed in the presence of copper chloride. The analysis of the solid residue obtained in the wheat straw pyrolysis in the presence of CuCl2 showed the increase in the specific surface area of the carbon residue from 24 up to 63.5 m2/g in comparison with that obtained for the noncatalytic process