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Background: In the production of biofuels from lignocellulosic material, biocrude plays a key role. The present work deals with the biocrude production through hydrothermal liquefaction (HTL) of birch wood in supercritical ethanol over 5 wt% Fe‐H‐Beta‐150 (SiO2 to Al2O3 ratio of 150) or 5 wt% Fe‐SiO2 catalyst. Results: The liquid and solid products were characterized with various analytical techniques such as gas chromatography mass spectrometry (GC–MS), gas chromatography with a flame ionization detector (GC‐FID), size exclusion chromatography (SEC), inductively‐coupled plasma mass spectrometry (ICP‐MS), powder X‐ray diffraction (p‐XRD), scanning electron microscopy (SEM), and solid‐state carbon‐13 magic angle spinning nuclear magnetic resonance (13C‐MAS‐NMR), respectively. The results revealed that 5 wt% Fe‐H‐Beta‐150, a strongly Brønsted acidic catalyst, enhanced the biocrude formation when compared with a non‐acidic 5 wt% Fe‐SiO2 catalyst. Hemicellulose and lignin degradation occurred resulting in formation of mainly sugars, acids‐esters and phenolic compounds in the liquid phase. The gaseous atmosphere of hydrogen also enhanced the degradation of biomass. The biocrude yield from birch was 25 wt% over 5 wt% Fe‐H‐Beta‐150. The Brønsted acidic catalyst gave higher dissolution efficiency and its clear catalytic effect was observed in comparison to non‐acidic 5 wt% Fe‐SiO2. The degradation level of lignin in the presence of 5 wt% Fe‐H‐Beta‐150 was high 68 wt% aromatic products were formed, while only 38 wt% was obtained with 5 wt% Fe‐SiO2. Conclusions: Hydrogen atmosphere enhances the fractionation of birch wood when compared to argon atmosphere. The 5 wt% Fe‐H‐Beta‐150 catalyst enhanced very strongly the degradation of hemicellulose and lignin in biomass to sugars and acid‐esters as well as phenolic compounds, respectively, compared to the non‐acidic 5 wt% Fe‐SiO2 catalyst. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Hydrodeoxygenation ( HDO) of Chlorella algal oil extracted with supercritical hexane and stearic acid as a model compound was investigated over several supported Ni and Mo2N-MoO2 catalysts in a semibatch reactor at 300 °C under 30 bar in the presence of hydrogen. RESULTS The results showed that all catalysts were very active in HDO of stearic acid. With crude algal oil, a maximum conversion of lipids of 35% was found with an acidic Ni- HY-80 zeolite catalyst after 360 min. The main products in algal oil HDO were fatty acids; whereas maximally only 7% hydrocarbons were formed with Ni- HY-80. The main hydrocarbon products were formed via decarbonylation, as the hydrogenation/dehydration route was suppressed. CONCLUSIONS Hydrodeoxygenation of crude Chlorella algal oil was demonstrated over nickel supported on beta zeolite and with a molybdenum oxide-nitride catalyst. Strong catalyst deactivation occurred for the former catalyst, whereas the latter retained its activity. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND In the lube oil re-refining industry silicon, coming mainly from antifoaming agents, is recognized to be a contaminant generating undesired solid deposits. The behavior of the hydrogen-terminated model compound, tetramethyldisiloxane, under base-catalyzed conditions was investigated at 100 °C in dodecane as the solvent with sodium siloxanolate as an alkali agent. RESULTS The use of sodium siloxanolates led to high reaction rates and selectivity to the liquid products. Experiments with an industrially relevant silicon-containing substrate, namely silicone-based antifoam agent showed that its transformation in the presence of 33 wt% aqueous solution of sodium hydroxide resulted in 80% yield of solid sodium siloxanolates, whereas, when sodium siloxanolate was used as an initial alkali agent, no solid products were formed. CONCLUSIONS Experimental results demonstrated that under alkali treatment conditions silicon-containing species existing in real industrial feedstock undergo transformation reactions, with formation of solid sodium siloxanolates. It was found that the use of sodium siloxanolate as an alkali agent could significantly increase the rate of polydimethylsiloxane depolymerization reaction and completely eliminate formation of the undesired solids under industrially relevant conditions. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Amidation of renewable feedstocks, such as fatty acids, esters, and Chlorella alga based biodiesel, was demonstrated with zeolites and mesoporous materials as catalysts and ethanolamine, alaninol, and leucinol. The last two can be derived from amino acids present in alga. The main products were fatty alkanol amides and the corresponding ester amines, as confirmed by NMR and IR spectroscopy. Thermal amidation of technical-grade oleic acid and stearic acid at 180 °C with ethanolamine were non-negligible; both gave 61 % conversion. In the amidation of stearic acid with ethanolamine, the conversion over H-Beta-150 was 80 % after 3 h, whereas only 63 % conversion was achieved for oleic acid; this shows that a microporous catalyst is not suitable for this acid and exhibits a wrinkled conformation. The highest selectivity to stearoyl ethanolamide of 92 % was achieved with mildly acidic H-MCM-41 at 70 % conversion in 3 h at 180 °C. Highly acidic catalysts favored the formation of the ester amine, whereas the amide was obtained with a catalyst that exhibited an optimum acidity. The conversion levels achieved with different fatty acids in the range C12-C18 were similar; this shows that the fatty acid length does not affect the amidation rate. The amidation of methyl palmitate and biodiesel gave low conversions over an acidic catalyst, which suggested that the reaction mechanism in the amidation of esters was different. [ABSTRACT FROM AUTHOR]

The extraction of oils based on animal fat and vegetable oil from two types of spent bleaching earths, namely from the acidic sepiolite and the nonacidic palygorskite, was investigated by the Soxhlet method with hexane as a solvent. The yields of oil were independent of the feedstock, whereas a much lower oil yield was obtained with palygorskite exhibiting also a smaller surface area as compared to sepiolite which provided a higher yield. The glyceride compositions were very similar in bleached and extracted oils, while slightly lower melting and crystallization energies were determined by differential scanning calorimetry for the extracted oils bleached with acidic clay indicating minor hydrolysis of triglycerides. [ABSTRACT FROM AUTHOR]

Mixtures of fatty acids and rosin acids are industrially important products utilized as a raw material for several purposes. Their thermal properties, especially cold stability and crystallization behavior is also important. Several fatty acid and rosin acid mixtures both from industrial products and from commercially available fatty and rosin acids were prepared and treated for 30 min at 80 °C under an inert atmosphere. Thereafter, the mixture was cooled to the desired temperature. Determination of the cloud point, chemical analysis of liquid and solid phase, thermal analysis by differential scanning calorimetry as well as morphology analysis by scanning electron microscopy were performed. The results revealed that crystallization was more rapid when it occurred at 10 °C compared to 25 °C. The crystal sizes increased with decreasing the crystallization temperature. Furthermore, crystals were of irregular shape and agglomerated when rapid cooling of the mixture occurred. Chemical analysis revealed that liquid phase was enriched with stearic acid, whereas crystals contained large amounts of abietic, dehydroabietic and linoleic acids. The cloud point of the mixtures increased with increasing amount of stearic and rosin acids. Dehydroabietic acid addition improved the cold stability of the synthetic fatty acid-rosin acids mixture. [ABSTRACT FROM AUTHOR]

ABSTRACT Polysaccharides are biorenewable and biodegradable starting materials for the development of functional materials. The synthesis of a monofunctional macroinitiator for single electron transfer-living radical polymerization was successfully developed from a wood polysaccharide- O-acetyl galactoglucomannan (GGM) using a beforehand synthesized amino-functional α-bromoisobutyryl derivative applying reductive amination. The GGM macroinitiator was employed to initiate a controlled radical polymerization of [2-(methacryloyloxy)ethyl]trimethylammonium chloride (MeDMA), methyl methacrylate (MMA), and N-isopropylacrylamide (NIPAM) using Cu0/Me6-Tren as a catalyst. The either charged or amphiphilic GGM- b-copolymers with different chain lengths of the synthetic block were successfully synthesized without prior hydrophobization of the GGM chain and dimethyl sulfoxide (DMSO) or DMSO/water mixtures were used as solvents. This novel synthetic approach may find untapped potentials particularly for the development of polysaccharide-based amphiphilic additives for cosmetics or paints and for the design of novel temperature or pH responsive polymers with such potential applications as in drug delivery systems or in biocomposites. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 5100-5110 [ABSTRACT FROM AUTHOR]