Catalytic Deoxygenation of the Oil and Biodiesel of Licuri (Syagrus coronata) To Obtain n-Alkanes with Chains in the Range of Biojet Fuels

Syagrus coronata fixed oil prevents rotenone-induced movement disorders and oxidative stress in Drosophila melanogaster

One prominent aspect of Parkinson's disease (PD) is the presence of elevated levels of free radicals, including reactive oxygen species (ROS). Syagrus coronata (S. coronata), a palm tree, exhibits antioxidant activity attributed to its phytochemical composition, containing fatty acids, polyphenols, and flavonoids. The aim of this investigation was to examine the potential neuroprotective effects of S. coronata fixed oil against rotenone-induced toxicity using Drosophila melanogaster. Young Drosophila specimens (3-4 d old) were exposed to a diet supplemented with rotenone (50 µM) for 7 d with and without the inclusion of S. coronata fixed oil (0.2 mg/g diet). Data demonstrated that rotenone exposure resulted in significant locomotor impairment and increased mortality rates in flies. Further, rotenone administration reduced total thiol levels but elevated lipid peroxidation, iron (Fe) levels, and nitric oxide (NO) levels while decreasing the reduced capacity of mitochondria. Concomitant administration of S. coronata exhibited a protective effect against rotenone, as evidenced by a return to control levels of Fe, NO, and total thiols, lowered lipid peroxidation levels, reversed locomotor impairment, and enhanced % cell viability. Molecular docking of the oil lipidic components with antioxidant enzymes showed strong binding affinity to superoxide dismutase (SOD) and glutathione peroxidase (GPX1) enzymes. Overall, treatment with S. coronata fixed oil was found to prevent rotenone-induced movement disorders and oxidative stress in Drosophila melanogaster.

Photocatalyzed hydrodecarboxylation of fatty acids: a prospective method to produce drop-in biofuels

A direct and practical method for photocatalyzed hydrodecarboxylation of fatty acids is reported herein. The catalytic system consists of a commercially available acridinium salt as the photocatalyst and thiophenol as the Hydrogen Atom Transfer (HAT) co-catalyst. Results evidenced that Cn-1 alkanes were obtained in yields up to 77%. Furthermore, the protocol was employed for a complex mixture of fatty acids bio-derived from a real sample of licuri oil to obtain hydrocarbons in the range of C9-C17 with high selectivity and excellent conversion (>90%). This work provides a powerful strategy for producing drop-in biofuels under mild conditions. Finally, an energetic assessment of our proposed protocol (∼22.9 kW h) reveals the benefit of a sustainable production of renewable hydrocarbons.

Photocatalytic Hydrodecarboxylation of Fatty Acids for Drop-in Biofuels Production

A mild, practical, and environmentally friendly method for the hydrodecarboxylation of fatty acids using an acridine-based photoredox catalyst and thiophenol was developed. Cn-1 alkanes were synthesized in good to excellent yields (up to 99 %) from C10-C18 saturated fatty acids under visible light irradiation (405 nm). The developed protocol was employed for a mixture of fatty acids obtained from the hydrolysis of Licuri oil, affording a mixture of C9-C17 hydrocarbons in quantitative yield, which demonstrates the potential application of the method to produce drop-in biofuels.

Investigation of Combustion of the Gas Turbine Engine from Kerosene and Biokerosene and Their Soot Characteristics in Diffusion Flames

Performances, emissions from the gas turbine engine, and soot formations in diffusion flames of kerosene (Jet A1) and its mixture with 5% by volume bioparaffins (known as BK-5) are reported in the present study. A Rover 1S/60 gas turbine engine was used for recording performance parameters and emissions. Soot characteristics were investigated in smoke-free coannular wick-fed diffusion flames. This study is the next step that must be performed in the certification process of a new aviation biofuel before it is tested in the aircraft. The results show that BK-5 produced a similar performance against Jet A1. Throughout the whole power range under investigation, BK-5 emitted 3.4% NOx higher than Jet A1, while Jet A1 released CO and HC at the rates that are, respectively, 1.8 and 4.5% greater than its counterpart. The soot emissions from the BK-5 and Jet A1 were comparable across the measured flame height range. The results encouraged future studies to carry out the modern engine and flight tests. The production process for bioparaffins employed in this work has been demonstrated to be viable and appropriate for tropical developing nations. The current process should also continue to be improved by eliminating high-distillation temperature components in bioparaffins.

Emerging Lipids from Arecaceae Palm Fruits in Brazil

Arecaceae palm tree fruits (APTFs) with pulp or kernel rich in oil are widely distributed in six Brazilian biomes. APTFs represent a great potential for the sustainable exploitation of products with high added value, but few literature studies have reported their properties and industrial applications. The lack of information leads to underutilization, low consumption, commercialization, and processing of these fruit species. This review presents and discusses the occurrence of 13 APTFs and the composition, physicochemical properties, bioactive compounds, and potential applications of their 25 oils and fats. The reported studies showed that the species present different lipid profiles. Multivariate analysis based on principal component analysis (PCA) and hierarchical cluster analysis (HCA) indicated a correlation between the composition of pulp and kernel oils. Myristic, caprylic, capric, and lauric acids are the main saturated fatty acids, while oleic acid is the main unsaturated. Carotenoids and phenolic compounds are the main bioactive compounds in APTFs, contributing to their high oxidative stability. The APTFs oils have a potential for use as foods and ingredients in the cosmetic, pharmaceutical, and biofuel industries. However, more studies are still necessary to better understand and exploit these species.

Production of Jet Biofuels by Catalytic Hydroprocessing of Esters and Fatty Acids: A Review

The transition from fossil to bio-based fuels is a requisite for reducing CO2 emissions in the aviation sector. Jet biofuels are alternative aviation fuels with similar chemical composition and performance of fossil jet fuels. In this context, the Hydroprocessing of Esters and Fatty Acids (HEFA) presents the most consolidated pathway for producing jet biofuels. The process for converting esters and/or fatty acids into hydrocarbons may involve hydrodeoxygenation, hydrocracking and hydroisomerization, depending on the chemical composition of the selected feedstock and the desired fuel properties. Furthermore, the HEFA process is usually performed under high H2 pressures and temperatures, with reactions mediated by a heterogeneous catalyst. In this framework, supported noble metals have been preferably employed in the HEFA process; however, some efforts were reported to utilize non-noble metals, achieving a similar performance of noble metals. Besides the metallic site, the acidic site of the catalyst is crucial for product selectivity. Bifunctional catalysts have been employed for the complete process of jet biofuel production with standardized properties, with a special remark for using zeolites as support. The proper design of heterogeneous catalysts may also reduce the consumption of hydrogen. Finally, the potential of enzymes as catalysts for intermediate products of the HEFA pathway is highlighted.

Nickel-catalyzed reductive decarboxylation of fatty acids for drop-in biofuel production

An operationally simple and highly selective method for the decarboxylation of fatty acids under remarkably mild conditions is described herein. The activation of the aliphatic carboxylic acids by esterification with N-hydroxyphthalimide (NHPI) enabled efficient deoxygenation to synthesize n-alkanes in up to 67% yield, employing inexpensive PMHS as a hydrogen source, NiCl₂·6H₂O, bipyridine, and zinc in THF. In contrast to the conventional thermo-catalytic approaches, this protocol does not require high temperature and high pressure of hydrogen gas to deoxygenate biomass-derived carboxylic acids, thus representing an attractive alternative for producing drop-in biofuels.

An operationally simple and highly selective method for the Ni-catalyzed decarboxylation of redox active esters (RAEs) derived from fatty acids under remarkably mild conditions is described herein.

Solvent-Free Hydrodeoxygenation of Triglycerides to Diesel-like Hydrocarbons over Pt-Decorated MoO2 Catalysts

In the present work, the solvent-free hydrodeoxygenation of palm oil as a representative triglyceride model compound to diesel-like hydrocarbons was evaluated in a batch reactor using Pt-decorated MoO₂ catalysts. The catalysts with various Pt loadings (0.5-3%) were synthesized by an incipient wetness impregnation method. The metallic Pt and MoO₂ phases were detected in the XRD patterns of as-prepared catalysts after the reaction and acted as active components for the deoxygenation reactions. The XPS experiments confirmed the existence of metallic Pt and PtO _x species. The XANES investigation of Mo L₃-edge spectra elucidated a change in the valence state by the transformation of MoO₃ into MoO₂ species after the deoxygenation reaction. The TEM observation revealed the formation of Pt nanoparticles in the range of 1-3 nm decorated on MoO₂ species. The number of acid sites increased with stronger metal-support interactions on increasing the Pt loading. The catalytic performance of the MoO₂ catalyst significantly improved with a small amount of Pt decoration. However, the further increase in Pt loading did not relatively increase the deoxygenation activity due to the formation of the agglomerated Pt particles. The high performance of the decorated catalysts could be attributed to the moderate acidity from the Pt dispersed on MoO₂ toward decarbonylation and decarboxylation reactions.

Catalytic Production of Jet Fuels from Biomass

Concerns about depleting fossil fuels and global warming effects are pushing our society to search for new renewable sources of energy with the potential to substitute coal, natural gas, and petroleum. In this sense, biomass, the only renewable source of carbon available on Earth, is the perfect replacement for petroleum in producing renewable fuels. The aviation sector is responsible for a significant fraction of greenhouse gas emissions, and two billion barrels of petroleum are being consumed annually to produce the jet fuels required to transport people and goods around the world. Governments are pushing directives to replace fossil fuel-derived jet fuels with those derived from biomass. The present mini review is aimed to summarize the main technologies available today for converting biomass into liquid hydrocarbon fuels with a molecular weight and structure suitable for being used as aviation fuels. Particular emphasis will be placed on those routes involving heterogeneous catalysts.