Elucidation of the active phase in PtSn/SAPO-11 for hydrodeoxygenation of methyl palmitate

Selectivity of reaction pathways for green diesel production towards biojet fuel applications

Green diesel is the second generation biofuel with the same structure as fossil fuels (alkanes), allowing this biofuel to provide excellent fuel properties over biodiesel such as higher energy content and lower hazardous gas emission. Generally, green diesel can be produced through the deoxygenation/hydrogenation of natural oil and/or its derivatives at 200-400 °C and 1-10 MPa over supported metal catalysts. This process comprises of three reaction pathways: hydrodeoxygenation, decarboxylation, and decarbonylation. The extent to which these three different pathways are involved is strongly influenced by the catalyst, pressure, and temperature. Subsequently, the determination of catalyst and reaction condition plays a significant role owing to the feasibility of the process and the economic point of view. This article emphasizes the reaction pathway of green diesel production as well as the parameters influencing the predominant reaction route.

Selective hydroconversion of coconut oil-derived lauric acid to alcohol and aliphatic alkane over MoO x -modified Ru catalysts under mild conditions

Molybdenum oxide-modified ruthenium on titanium oxide (Ru-(y)MoO _x /TiO₂; y is the loading amount of Mo) catalysts show high activity for the hydroconversion of carboxylic acids to the corresponding alcohols (fatty alcohols) and aliphatic alkanes (biofuels) in 2-propanol/water (4.0/1.0 v/v) solvent in a batch reactor under mild reaction conditions. Among the Ru-(y)MoO _x /TiO₂ catalysts tested, the Ru-(0.026)MoO _x /TiO₂ (Mo loading amount of 0.026 mmol g^-1) catalyst shows the highest yield of aliphatic n-alkanes from hydroconversion of coconut oil derived lauric acid and various aliphatic fatty acid C6-C18 precursors at 170-230 °C, 30-40 bar for 7-20 h. Over Ru-(0.026)MoO _x /TiO₂, as the best catalyst, the hydroconversion of lauric acid at lower reaction temperatures (130 ≥ T ≤ 150 °C) produced dodecane-1-ol and dodecyl dodecanoate as the result of further esterification of lauric acid and the corresponding alcohols. An increase in reaction temperature up to 230 °C significantly enhanced the degree of hydrodeoxygenation of lauric acid and produced n-dodecane with maximum yield (up to 80%) at 230 °C, H₂ 40 bar for 7 h. Notably, the reusability of the Ru-(0.026)MoO _x /TiO₂ catalyst is slightly limited by the aggregation of Ru nanoparticles and the collapse of the catalyst structure.

Hydro-treating and Hydro-isomerisation of Sunflower Oil using Pt/SAPO-11: Influence of Templates in Ultrasonic Assisted with Hydrothermal Synthesis

Pt/SAPO-11 mesopores type materials has successfully synthesized using different templates, such as: diethylamine (DEA), dimethylamine (DMA), and n-propylamine (n-PA), under ultrasonication coupled with hydrothermal treatment or independently with hydrothermal treatment. The influences of structure directing agent (SDA) and synthesis method are investigated by different characterization techniques and the role of the material as catalyst in hydrotreating of sunflower oil has examined. The synthesized materials have been characterized by X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), and Fourier Transform Infra Red (FT-IR) techniques. It is found that SAPO-11 material which has synthesized with n-PA as a template has the characteristics of high silicon incorporation. Hydrotreating of sunflower oil is carried out in a fixed bed reactor with Pt impregnated SAPO-11 catalyst and a detailed study on the isomerization is performed by varying the operating parameters like temperature and space velocity. The high selectivity of Pt/SAPO-11 catalyst is achieved by uniform pore size and acidity. Also the pore opening of the catalyst has a major effect in the selectivity of the catalyst. Further, it represents a higher ratio of isomers compared to other synthesized catalysts on hydro-treating of sunflower oil.  Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0). 

Recent advances in one-stage conversion of lipid-based biomass-derived oils into fuel components - aromatics and isomerized alkanes

Nowadays, production of biofuels is a rather hot topic due to depleting of conventional fossil fuel feedstocks and a number of other factors. Plant lipid-based feedstocks are very important for production of diesel-, kerosene-, and gasoline-like hydrocarbons. Usually, (hydro)deoxygenation processes are aimed at obtaining of linear hydrocarbons known to have poor fuel characteristics compared to the branched ones. Thus, further hydroisomerization is required to improve their properties as motor fuel components. This review article is focused on conversion of lipid-based feedstocks and model compounds into high-quality fuel components for a single step - direct cracking into aromatics and merged hydrodeoxygenation-hydroisomerization to obtain isoparaffins. The second process is quite novel and a number of the research articles presented in the literature is relatively low. As auxiliary subsections, hydroisomerization of straight hydrocarbons and techno-economic analysis of renewable diesel-like fuel production are briefly reviewed as well.

Hydrodeoxygenation of ethyl stearate over Re-promoted Ru/TiO2 catalysts: rate enhancement and selectivity control by the addition of Re

The addition of Re to Ru/TiO₂ could promote the reaction rate and product selectivity of n-C₁₈H₃₈via adjusting acid sites.

Efficient hydrogenation performance improvement of MoP and Ni2P catalysts by adjusting the electron distribution around Mo and Ni atoms

The catalyst (MoP) was modified by higher electronegativity element W and lower electronegativity element Cu, realizing the control of hydrogenation performance of the catalysts.