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Sugarcane bagasse is abundant agro-industrial waste that can be potentially utilized as a source of valuable compounds and biopolymers. In the present study, sugarcane bagasse from Brazil was fractionated employing an environmentally friendly hydrotropic process. Several treatments were carried out at 150 and 170 °C and dwell times of 60 and 120 min using unmodified 30% hydrotropic solutions as well as the solutions acidified with formic acid. The major produced fraction was cellulose pulp obtained with the yield of 44–67% (bagasse based) and the cellulose content of 60–92%. Lignins dissolved during the treatments were isolated from the spent solutions by dilution with water and filtration. The yields of the lignins were 11.8–14.7% (bagasse based) and their purity ranged from 88 to 94%. Generally, the purity of both fractions and the yield of lignin were higher at more severe process conditions. However, the more severe conditions resulted in lower average molar masses of the lignins and lower intrinsic viscosity values of the cellulose fractions. The composition of the spent solutions also varied with the treatment conditions, and, besides the lignins, they contained different amounts of dissolved hemicelluloses, sugar monomers, furfural and acetic and formic acids. The results of the present study showed that the hydrotropic process could be successfully applied for the valorization of sugarcane bagasse by its fractionation into lignin, cellulose and other products. [ABSTRACT FROM AUTHOR]

Arbutus andrachne and Platanus orientalis grow naturally in Turkey. They do not occur in stands but can be seen as solitary trees. A. andrachne is seen in coastal parts of Anatolia, whereas P. orientalis can be found from west to the east of Turkey, mostly in river banks. Lipophilic extractives, hydrophilic extractives, and suberin monomers from Arbutus andrachne and Platanus orientalis bark was analyzed by chromatography. The total amount of lipophilic extractives was higher in P. orientalis (8.55 mg/g). However, the total amount of hydrophilic extractives had a bigger proportion, 100.86 mg/g, in A. andrachne bark. Dioic and hydroxy acids were the dominant group in the suberin monomers of both species of bark. Acid 1,18-dioic-18:0 and acid 18-hydroxy-18:1 were determined as the main compounds of suberin monomers in both samples. In addition, total amount of suberin monomers was determined to be 11.36 mg/g in A. andrachne and 15.95 mg/g in P. orientalis bark. [ABSTRACT FROM AUTHOR]

The extraction conditions have been evaluated concerning the recovery of specific polyphenols from Scots pine (Pinus sylvestris) knots by means of an accelerated solvent extractor. The composition of the extracts was determined by gas chromatography, gas chromatographymass spectrometry, and high-performance size-exclusion chromatography. The main phenolic compounds are the stilbenes pinosylvin and its monomethyl ether and the lignan nortrachelogenin (NTG), and their amounts vary a lot from sample to sample. The sequential extraction with a nonpolar solvent as a first step for removing the lipophilic compounds was the most efficient approach for the recovery of both pinosylvins and NTG. For food applications, hot water and 85% aqueous ethanol were good solvents for the production of the substances in focus. An industrial knotwood sample from a pulp mill was sequentially extracted with cyclohexane and ethanol/water (95:5) in a large-scale Soxhlet equipment. The results show that the industrial production of pinosylvins and NTG from knots is feasible. [ABSTRACT FROM AUTHOR]

Highlights: [⿢] Pinus pinaster wood samples were extracted with near and supercritical CO2. [⿢] The effect of pressure (10⿿25MPa), temperature (30⿿50°C) and ethanol as co-solvent was assessed. [⿢] Under selected conditions (25MPa, 50°C, 10% ethanol), 4wt% was extracted. [⿢] One gram of extract contained 76mg of GAE and was equivalent to 0.3g Trolox. [⿢] Selected extracts contained 30% resin acids and 10% of the sum of flavonoids, lignans, stilbenes and juvabiones. [ABSTRACT FROM AUTHOR]

The lipophilic extractives, that is, wood resin, in Populus grandidentata (bigtooth aspen) and Populus tremuloides (quaking aspen) sapwood, heartwood, and knots were analyzed. The amount and composition of the extractives in sapwood were similar in both species. Triglycerides, short-chain fatty acids, and steryl esters were predominant in sapwood samples. The knots of both species contained similar amounts of extractives as the stemwood, but the composition was quite different. Monoglycerides; long-chain fatty acids and alcohols, with 22 to 28 carbon atoms; hydroxy fatty acids; and ferulic acid esters of fatty alcohols were the major components in heartwood and knots, but were minor components in the sapwood. [ABSTRACT FROM AUTHOR]

Hazelnut (HS) and walnut (WS) shells, an abundant by-product of the processing industries of these edible nuts, are traditionally considered as a low-value waste. However, they are a source of valuable compounds with an interesting chemical profile for the chemical and pharmaceutical sectors. In this study, the lipophilic and hydrophilic extracts present in HS and WS were quantified and identified, then the polar fractions were chromatographically separated, and their antioxidant capacity was studied. The experimental work includes the isolation of crude lipophilic and hydrophilic extracts by an accelerated extraction process, chromatographic analysis (gas chromatography-flame ionization (GC-FID), GC-mass spectroscopy (GC-MS), high-performance size-exclusion chromatography (HPSEC), thin-layer chromatography (TLC)), and quantification of the components. In addition, a thorough compositional characterization of the subgroups obtained by flash chromatography and their antioxidant capacity was carried out. The gravimetric concentrations showed different lipophilic/hydrophilic ratios (0.70 for HS and 0.23 for WS), indicating a higher proportion of polar compounds in WS than in HS. Moreover, the lipophilic extracts were principally composed of short-chain fatty acids (stearic, palmitic, and oleic acid), triglycerides, and sterols. The polar fractions were screened by thin-layer chromatography and then separated by flash chromatography, obtaining fractions free of fatty acids and sugar derivatives (97:3 in HS and 95:5 in WS), and mixtures richer in phenolic compounds and flavonoids such as guaiacyl derivatives, quercetin, pinobanksin, and catechin. The most polar fractions presented a higher antioxidant capacity than that of the crude extracts. [ABSTRACT FROM AUTHOR]

The production of biofuels and other chemicals from lignocellulosic biomass is limited by the inefficiency of enzymatic hydrolysis. Here a biomimetic composite material consisting of bacterial cellulose and wood-based hemicelluloses was used to study the effects of hemicelluloses on the enzymatic hydrolysis with a commercial cellulase mixture. Bacterial cellulose synthesized in the presence of hemicelluloses, especially xylan, was found to be more susceptible to enzymatic hydrolysis than hemicellulose-free bacterial cellulose. The reason for the easier hydrolysis could be related to the nanoscale structure of the substrate, particularly the packing of cellulose microfibrils into ribbons or bundles. In addition, small-angle X-ray scattering was used to show that the average nanoscale morphology of bacterial cellulose remained unchanged during the enzymatic hydrolysis. The reported easier enzymatic hydrolysis of bacterial cellulose produced in the presence of wood-based xylan offers new insights to overcome biomass recalcitrance through genetic engineering. [ABSTRACT FROM AUTHOR]

Various lignin determination methods have been applied to hemicellulose-rich wood extracts obtained after pressurized hot-water extraction (PHWE) and membrane ultrafiltration (UF). In focus were the chlorine number (Cl no.) method, the acetyl bromide method, and the four modifications of the Klason lignin determination, such as the KCL, TAPPI, LAP, and Goldschmid methods. The furfural (F) and hydroxymethylfurfural (HMF) concentrations in the acid hydrolysates were also determined. The mass balances of the fraction were calculated with respect to the contents of dry solids and lignin, including the acid-soluble lignin. The reliability of the methods was evaluated based on the lignin mass balances and the gross chemical composition of the extracts. Although the results were dependent on the method applied, the lignin mass balance calculations yielded similar results in general. [ABSTRACT FROM AUTHOR]

Pinus pinaster wood samples, obtained at different positions of three healthy trees, were subjected to two sequential extractions using an Accelerated Solvent Extraction instrument. The first extraction was carried out with hexane (to remove lipophilic extractives) and the second one with acetone/water (95:5 v/v) to recover bioactive phenolic compounds, the target compounds of this study. The extracted fractions were assayed for total yield and composition. The extracts contained a spectrum of phenolic compounds (simple phenolics, phenolic stilbenes, flavonoids and lignans) and non-phenolic components (juvabiones, resin and fatty acids, steryl esters and triglycerides). The fractionation effects achieved by consecutive extractions and the recovery of bioactive phenolics are discussed. [ABSTRACT FROM AUTHOR]

A class of nonionic polysaccharides-based surfactants were synthesised from O-acetyl galactoglucomannan (GGM), water-soluble hemicelluloses from spruce, using naturally-occurring saturated fatty acids, CH3(CH2)nCOOH (n = 7, 12, and 16). Hemicelluloses can be recovered from waste-streams of papermaking and agricultural processes or isolated by hot water extraction of plant tissues integrated into a biorefinery process. Fatty acids can be recovered as byproducts of the agricultural and food industries. Different synthesis routes were applied to yield amphiphilic derivatives with either a grafted or block structure. Fatty acids activated with 1,1'-carbonyldiimidazole (CDI) were grafted to the backbone of GGM molecules on their hydroxyl groups. Alternatively, synthesised amino-activated fatty acids using ethylenediamine were reacted with the reducing end of GGM. By adjusting the reagent ratios, GGM-based surfactants with different hydrophilic to hydrophobic ratios were prepared. Their surface activity was assessed by measuring the surface tension in water. This study presents an approach to design carbohydrate-based surfactants using naturally-occurring fatty acids that may find potential applications in such areas as food, cosmetic, and paint formulations. [ABSTRACT FROM AUTHOR]

Aqueous fractionation of wood has been proposed as a suitable processing method for biorefineries. When treatments are performed under low severity conditions, water-soluble components (which could be detrimental in further processing stages) are removed, whereas polysaccharides, lignin, and other water-insoluble constituents remain in solid phase with little alteration. In order to explore the presence of added-value products in aqueous extracts from Pinus pinaster wood, different samples (heartwood and sapwood with and without knots) were extracted with water at 130 to 140 °C, and the resulting solutions were assayed for yield and composition (by GC-FID, GC-MS, and HPLC). The major extract components, such as polysaccharide-derived products, simple phenolics, stilbenes, lignans, flavonoids, organic acids, jubaviones, steryl esters, and triglycerides, were identified and quantified. In order to assess a possible application of the extracts, their antioxidant activity was measured using the Trolox Equivalent Antioxidant Capacity assay. [ABSTRACT FROM AUTHOR]

Waste fish oils (FOs) and used cooking vegetable oils (UCOs) are increasingly becoming alternative renewable fuels. However, different physicochemical aspects of these renewable fuels, including the effect of storage, are not well-known. In this work, the effect of the storage period on physicochemical properties of selected samples of FOs and UCOs was investigated. The bio-oils were stored at 4 °C for up to five years before each experimentation. The chemical properties were characterized using capillary gas chromatography with flame ionization detection (GC-FID) and high-performance size exclusion chromatography including an evaporative light scattering detector (HPSEC-ELSD). Water contents and acid numbers of the bio-oils were determined using the Karl Fischer (KF) titration and the ASTM D 664 methods. Furthermore, the average heating values and surface tension of the bio-oils were determined. According to the results obtained, for all bio-oil types, the concentrations of polymerized triglycerides, diglycerides, and fatty acids and monoglycerides had increased during the storage periods. The physical properties of the bio-oils also showed a small variation as a function of the storage period. The overall results observed indicate that the deterioration of the physicochemical properties of bio-oils can be controlled through storage in dark, dry, and cold conditions. [ABSTRACT FROM AUTHOR]

The first goal of this study was to determine the polysaccharide composition of Pinus brutia wood and how this composition changes during kraft pulping. The second goal was to determine the effect of the stem height on chemical composition. The content of hemicelluloses was about 280 mg/g at a height of 1.3 m, whereas the content was about 300 mg/g at the top of the stem (4.3 m). The main sugars in the wood of P. brutia were mannose (102 mg/g dw), xylose (69 mg/g dw), and glucose (44 mg/g dw). During kraft pulping, 52% of the total hemicelluloses were degraded. Glucose and xylose were more stable than mannose. The total amounts of cellulose in the wood and in the kraft pulp of P. brutia were determined to be 330 mg/g and 661 mg/g, respectively, at 1.3 m. [ABSTRACT FROM AUTHOR]

Highlights • Hemicelluloses were obtained via alternative wood biorefining strategies. • Hemicelluloses were compared as biobased emulsion stabilizers. • Sustainable alkyd paint emulsions were characterized. • Natural hemicellulose-rich isolates showed promising functionality. • The crude technical hemicellulose fractions were the most efficient stabilizers. Abstract Wood biorefining currently involves large-scale industrial processes where a notable portion of raw materials, namely hemicelluloses and lignin, are either lost with the process water, degraded, or burnt for energy. Value-added utilization of polymeric hemicelluloses is challenging due to their intermediate molar mass and the presence of other wood components, such as phenolic residues or wood extractives. Oil-in-water (O/W) emulsions represent a diverse and abundant class of applications in which the natural properties of wood hemicelluloses are beneficial. In the current work, we present highly promising new technical alkyd paint emulsion systems stabilized with hardwood glucuronoxylans (GX) and softwood galactoglucomannans (GGM). Samples from three isolation methods and their further fractionation by ethanol precipitation were systematically compared with regard to hemicellulose composition, interfacial activity, and functionality in emulsions. Emulsification of alkyd resins was successful with both GX and GGM obtained by various biorefining strategies. The highest emulsion stability over storage was achieved using crude non-purified GX and GGM fractions, and was correlated with the presence of phenolic compounds and extractives, interfacial activity, and small droplet size. Hardwood GX and softwood GGM are envisioned as natural emulsifiers of alkyd O/W emulsions, which are examples of diverse and abundantly-used technical dispersions. This study can be utilized as a guideline for targeted extraction of hemicelluloses with desired functionality, and as a protocol for developing environmentally-compatible industrial dispersions. [ABSTRACT FROM AUTHOR]

Betulin (90–94%) was extracted from birch with a non-polar solvent and recrystallized from 2-propanol. Liquid-phase oxidation of betulin aimed at obtaining its biologically active oxo-derivatives (betulone, betulonic and betulinic aldehydes), exhibiting e.g. antitumor, anti-inflammatory, antiparasitic, anticancer and anti-HIV properties, was demonstrated for the first time over gold-based catalysts. Gold was deposited on pristine TiO2 and the same support modified with ceria and lanthana, followed by pretreatment with a H2 or O2 atmosphere. The catalysts were characterized by XRD, BET, ICP, TEM, XPS, DRIFT CO, TPD of NH3 and CO2 methods. The nature of the support, type of modification and the pretreatment atmosphere through the metal–support interactions significantly influenced the average particle size of gold, its distribution and the electronic state of gold, as well as the acid–base properties and, thereby, the catalytic performance (activity and selectivity) in betulin oxidation. Au/La2O3/TiO2 pretreated in H2 displayed the highest catalytic activity in betulin oxidation among the studied catalysts with selectivities to betulone, betulonic and betulinic aldehydes of 42, 32 and 27%, respectively, at 69% conversion. Side reactions resulting in oligomerization/polymerization products occurred on the catalyst surface with the participation of strong acid sites, diminishing the yield of the desired compounds. The latter was improved by adding hydrotalcite with the basic properties to the reaction mixture containing the catalyst. Kinetic modelling through numerical data fitting was performed to quantify the impact of such side reactions and determine the values of rate constants. [ABSTRACT FROM AUTHOR]

The aim of the study was to find appropriate non-chlorinated solvent systems for the extraction and separation of pure pinosylvin (PS) and pinosylvin monomethylether (PSMME) from Scots pine/Norway spruce wood residues. The extraction was performed in a pressurized solvent extractor and the purification and isolation of pure substances was done by flash chromatography. More precisely, pure PS was isolated via sequential flash chromatography in two repetitions in the gradient mode of the mobile phase, with cylcohexane (CX) and ethylacetate (EtOAc), beginning with 100% CX and ending up with 100% EtOAc. The extractives were qualitatively and quantitatively analyzed in terms of PS and PSMME contents by gas chromatography-flame ionization detector (GC-FID), gas chromatography-mass spectrometry (GC-MS), high-performance liquid chromatography (HPLC) and proton nuclear magnetic resonance (1H-NMR) spectroscopy. [ABSTRACT FROM AUTHOR]

Abstract: Vanillin hydrodeoxygenation was investigated using Pt/C catalyst in the temperature and total pressure ranges of 80-200 °C and 20-30 bar in several solvents, such as tetrahydrofuran, 2-propanol, water and in solventless conditions using 1:1 mass ratio of vanillin to guaiacol. The results revealed that the rate increased with increasing solvent polarity as follows: tetrahydrofuran < 2-propanol < water. The main product was p-creosol with 66% selectivity at complete vanillin conversion in HDO under 30 bar total pressure at 100 °C after 4 h using water as a solvent. In a solventless experiment with 1:1 mass ratio of vanillin-guaiacol as a feedstock only vanillin was transformed to p-creosol with 91% conversion in 4 h at 200 °C under 30 bar total pressure, while guaiacol did not produce any HDO products. Both thermodynamic analysis and kinetic modelling were performed. Vanillin hydrodeoxygenation resulted in formation of p-creosol over Pt/C catalyst using an optimum vanillin initial concentration in water solution. From the industrial point of view vanillin hydrodeoxygenation proceeded rapidly giving high yields of p-creosol in solventless hydrodeoxygenation of vanillin-guaiacol mixture, while guaiacol was not deoxygenated.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Hemicelluloses, the second most abundant polysaccharide right after cellulose, are in practice still treated as a side-stream in biomass processing industries. In the present study, we report an approach to use a wood-derived and side-stream biopolymer, spruce wood hemicellulose (galactoglucomannan, GGM) to partially replace the synthetic PLA as feedstock material in 3D printing. A solvent blending approach was developed to ensure the even distribution of the formed binary biocomposites. The blends of hemicellulose and PLA with varied ratio up to 25% of hemicellulose were extruded into filaments by hot melt extrusion. 3D scaffold prototypes were successfully printed from the composite filaments by fused deposition modeling 3D printing. Combining with 3D printing technique, the biocompatible and biodegradable feature of spruce wood hemicellulose into the composite scaffolds would potentially boost this new composite material in various biomedical applications such as tissue engineering and drug-eluting scaffolds. [ABSTRACT FROM AUTHOR]

The lipophilic and hydrophilic extractives in the sapwood (sW) and heartwood (hW) of stems from Pinus halepensis Mill and Eucalyptus camaldulensis Dehnh trees grown in the north of Algeria were analyzed. The extraction of dried samples was carried out in an accelerated solvent extractor (ASE). The lipophilic substances were first extracted with n-hexane and then the hydrophilic ones with acetone/water. The extractives were analyzed by gas chromatography-flame ionization detection (GC-FID), GC-mass spectroscopy (MS) and high-performance size-exclusion chromatography (HPSEC). The largest amount of lipophilic extractives (≈13.4 mg g-1) was observed in the hW of P. halepensis, while the hW of E. camaldulensis contained the largest amount of hydrophilic extractives (≈116.3 mg g-1). Lipophilic extractives are mainly composed of oleoresins (resin acids, terpenes), fats (fatty acids, glycerides, steryl esters, sterols) and waxes (fatty alcohols). Hydrophilic extractives are composed of polyphenols (stilbenes, flavanols), sugars (monosaccharides) and sugar alcohols (cyclic polyols). The main identified lipophilic extractives are resin acids in pine and glycerides in eucalypt. The main identified hydrophilic extractives are cyclic polyols in pine and flavanols and monosaccharides in eucalypt. The total content of extractives is higher in hW than in sW. [ABSTRACT FROM AUTHOR]

Sulfur-free Ni supported on H-Y zeolites, γ-Al 2 O 3 and SiO 2 synthesized by the wet impregnation method, and Pd/C were tested in hydrodeoxygenation (HDO) of stearic acid. The catalysts were forming n- heptadecane except Ni/H-Y-80, which was producing n- heptadecane and n- octadecane. Ni/H-Y 80 and Pd/C were tested on HDO of fatty acid methyl esters from chlorella, tall oil fatty acids, and animal fat. The reactions converting the substrates to the final products followed the path from unsaturated esters to acids, with hydrogenation of the latter into alcohols (i.e., stearyl alcohol), and finally formation of hydrocarbons. Ni/H-Y-80 permitted rapid and complete conversion into hydrocarbons, while Pd/C displayed 5–20 times lower turnover frequency, producing saturated intermediates along with hydrocarbons. The catalyst reusability of Ni supported on Y zeolites was studied by recycling and regenerating the spent catalyst from fatty acid HDO. The catalysts demonstrated the possibility of restoring the rates per unit of surface area after regeneration. Catalysts used in HDO of different feedstocks were investigated by thermogravimetric analysis, inductively coupled plasma-optical emission spectroscopy, transmission electron microscopy, surface area measurements, and pore size analysis. [ABSTRACT FROM AUTHOR]

Extraction of lipids from Chlorella algae with supercritical hexane resulted in the high lipids yield of approximately 10% obtained at optimum conditions in terms of extraction time and agitation compared to the total content of lipids being 12%. Furthermore, an easiness of hexane recovery may be considered as economically and ecologically attractive. For the first time, in the current work catalytic hydrodeoxygenation (HDO) of Chlorella algal lipids was studied over 5 wt % Ni/SiO2 at 300 °C and under 30 bar total pressure in H2. The conversion of lipids was about 15% as the catalyst was totally deactivated after 60 min. The transformation of lipids proceeded mostly via hydrogenation and hydrogenolysis with formation of free fatty acid (FFA). Lower activity might be attributed to deactivation of catalysts caused by chlorophylls and carotenoids. Even though the conversion is low, future studies in HDO of lipids extracted from other algae species having higher lipid content could be proposed. A coke resistant catalyst might be considered to improve catalytic activity. [ABSTRACT FROM AUTHOR]

The influence of oxygen (0–50 bar) on the molar mass and composition of hemicelluloses after hydrothermal treatment of spruce chips was studied in a batch reactor setup at 130 °C–160 °C. Purified galactoglucomannan was studied as a reference. The dissolved oxygen enhanced significantly the depolymerization of hemicelluloses from over 15,000 g/mol to 180 g/mol (monomers) as well as promoted acids formation from the monosaccharides. About 2–3 times faster depolymerization was observed already with rather low amounts of oxygen (2–8 bar), while the kinetics of depolymerization was significantly slower in inert atmosphere. The decrease in pH from neutral to as low as 2.5 lead to an autocatalytic effect on the polysaccharide hydrolysis and the consecutive reactions of monosaccharides. The results emphasize the importance of performing hydrothermal treatment under inert atmosphere if large polymeric hemicellulsoses are desired or if monosaccharides are targeted in hydrolysis of hemicelluloses. If autocatalysis begins, it is difficult to stop. [Display omitted] [ABSTRACT FROM AUTHOR]

In torrefaction, the mass yield depends on the biomass type, size of the biomass, torrefaction temperature, and residence time. Mass yield curves vs. residence time are usually modeled based on biomass type at different torrefaction temperature. This work is the second part of a study on the effect of alkali metals on torrefaction in which the K content affects the degradation of biomass during torrefaction. In this part of the study, the mass loss of spruce wood with different content of K was modeled using a two-step reaction model based on four kinetic rate constants. The results show that it is possible to model the mass loss of spruce wood doped with different levels of K using the same activation energies but different pre-exponential factors for the rate constants. Three of the pre-exponential factors increased linearly with increasing K content, while one of the pre-exponential factors decreased with increasing K content. Therefore, a new torrefaction model was formulated using the hemicellulose and cellulose content and K content. The new torrefaction model was validated against the mass loss during the torrefaction of aspen, miscanthus, straw and bark. There was good agreement between the model and the experimental data for the other biomasses, except bark. For bark, the mass loss of acetone extractable material was also needed to be taken into account. The new model can describe the kinetics of mass loss during torrefaction of different types of biomass. This is important for considering fuel flexibility in torrefaction plants. [ABSTRACT FROM AUTHOR]

Hemicellulose O-acetyl-galactoglucomannan (GGM) is the main noncellulosic water-soluble polysaccharide in the coniferous softwood Norway spruce, consisting of anhydro-galactose, -glucose, and -mannose. Acid hydrolysis of GGM has been studied in a continuous tube reactor to obtain these sugars under industrially relevant conditions. The reaction was performed under atmospheric pressure at 90°C and 95°C, and hydrochloric acid (HCl) served as catalyst. The influence of the reaction parameters, such as acid concentration (pH), temperature, concentration of the substrate, as well as catalyst and reactant flow rates, has been studied on the conversion efficiency and product distribution. Continuous production of monomeric sugars was achieved without formation of low-molecular by-products. The GGM conversion was high with HCl as catalyst, at 95°C, and a pH of 0.3. The main hydrolysis products were mannose, glucose, and galactose monomers. Minor amounts of sugar dimers were detected among the products. The experimental results are described with a laminar flow model for the continuous reactor. [ABSTRACT FROM AUTHOR]

In situ transesterification of Chlorella alga was performed using 5–20 wt% sulfuric acid as a catalyst at either 60 or 100 °C. The maximum ester yield in the range of 96–98% is comparative to the specification of ester content in biodiesel, 96%. A high excess of methanol was used in transesterification ensured also a high ester yield. The FAME was purified via adsorption of chlorophyll and carotenoids onto a clay. Properties of the purified biodiesel were investigated with several methods. The results showed that the Chlorella based biodiesel exhibits slightly lower oxidative and thermal stability compared to soybean based biodiesel due to the presence of polyunsaturated FAMEs. In addition to biodiesel, also the residual biomass was characterized showing that it contained sugars and proteins. An additional hydrogenation would increase the oxidative stability. Hydrodeoxygenation of Chlorella based biodiesel was also demonstrated over 5 wt% Ni–HY-80 zeolite with SiO 2 /Al 2 O 3 ratio of 80 and with 5 wt% Pd/C at 300 °C and 30 bar in dodecane as a solvent. Ni–HY-80 was superior to Pd/C catalyst giving more than 95% yield of hydrocarbons. [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]

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]

Abstract: Norway spruce O-acetyl-galactoglucomannans (GGM) are water-soluble hemicelluloses that have potential to be produced in large scale as a side product of the mechanical pulping industry or by hot-water extraction of wood. Chemical modification is often needed to tailor such water-soluble polysaccharides into industrially valuable compounds. In this work, treatment of GGM with butyric and benzoic anhydride in pyridine/dimethylformamide rendered GGM derivatives, which were hydrophobic and partially soluble in organic solvents. The degree of substitution can be adjusted by varying the quantity of the reagent and reaction temperature. The dn/dc value for the benzoyl ester of GGM was determined in 0.05M LiBr DMSO in order to obtain accurate molar mass analysis with SEC-MALLS-RI. Novel substances with adjusted hydrophobicity can thus be prepared on one step synthesis from natural hemicelluloses, which then showed a slight increase in the molar mass upon esterification. [Copyright &y& Elsevier]

Abstract: The changes in the amount and composition of suberin monomers of Scots pine outer bark, which is grown natively in Turkey, was investigated as a function of growing altitude. Samples were taken from every 100m to 1300m which was the highest point of the sampling area. While the total amount of suberin monomers is varied within the range 17.56–47.20mg/g, there was no correlation between total amount and altitude. Total amount of alkanols of suberin monomers decreased when the altitude increased. Alcohol 24:0 was seen as the dominant constituent and its amount decreased from 100m to 1300m. There was not a clear change in the total amount of alkanoic, dioic and hydroxy acids. Acid 1,18-hydroxy-18:1 and acid 1,18-dioic-18:1 were determined as the main compounds in all samples. [Copyright &y& Elsevier]

Abstract: The composition of Scots pine bark, its degradation, and the production of hydrolytic and ligninolytic enzymes were evaluated during 90days of incubation with Phanerochaete velutina and Stropharia rugosoannulata. The aim was to evaluate if pine bark can be a suitable fungal substrate for bioremediation applications. The original pine bark contained 45% lignin, 25% cellulose, and 15% hemicellulose. Resin acids were the most predominant lipophilic extractives, followed by sitosterol and unsaturated fatty acids, such as linoleic and oleic acids. Both fungi degraded all main components of bark, specially cellulose (79% loss by P. velutina). During cultivation on pine bark, fungi also degraded sitosterol, produced malic acid, and oxidated unsaturated fatty acids. The most predominant enzymes produced by both fungi were cellulase and manganese peroxidase. The results indicate that Scots pine bark supports enzyme production and provides nutrients to fungi, thus pine bark may be suitable fungal substrate for bioremediation. [Copyright &y& Elsevier]

Abstract: Acid hydrolysis, acid methanolysis, and enzymatic hydrolysis were compared for depolymerization of five different plant materials containing uronic acids. The analyzed plant materials were oat spelt, wheat straw, spruce thermomechanical pulp, aspen stemwood, and totally chlorine-free (TCF) bleached hardwood kraft pulp. Furthermore, GC (using both HP-1 and HP-5 capillary columns and FID and MSD detectors), HPAEC-PAD, and HPAEC-Borate techniques were compared for subsequent analysis of the released monosaccharides. It was shown that acid methanolysis combined with GC analysis is a convenient method for obtaining the sugar unit composition and amount of non-crystalline polysaccharides in different plant materials. The methanolysis method was generally superior to the hydrolysis method for xylan- and uronic acid-containing samples. However, acid and enzymatic hydrolysis showed the highest recoveries for bleached chemical pulp samples. Acid hydrolysis is also required for crystalline polysaccharides, but the strong acid conditions evidently lead to degradation of labile sugars. The plant methanolysates were not suitable as such for analysis on an HPAEC-PAD system. For analysis of the total amount of sugar units, hence including cellulose, other non-crystalline hemicelluloses, and pectins, a combination of the methanolysis and hydrolysis methods is recommended. [Copyright &y& Elsevier]

Abstract: Thermal and catalytic oligomerisation of technical grade linoleic acid was investigated under argon atmosphere at 280°C. The most efficient catalyst was H-MCM-41 followed by H-Beta 75. Several types of products, such as cyclic and aromatic compounds were formed indicating a complex reaction network for catalytic oligomerisation of fatty acids. [Copyright &y& Elsevier]

• Successive chemical treatments were optimized to purify cellulose fibers from raw Ampelodesmos mauritanicus. • Nanocellulose substrates were isolated from Ampelodesmos mauritanicus by mechanical treatment or acid hydrolysis. • TEMPO-mediated oxidation pretreatment was used for the production of cellulose nanofibrils with controled degree of oxidation. • Cellulose nanocrystals and cellulose nanofibrils isolated from Ampelodesmos mauritanicus form stable suspensions in water. In this work nanocellulose substrates e. g. cellulose nanofibrils and nanocrystals were isolated from an abundant renewable resource Ampelodesmos mauritanicus fibers. Cellulose nanocrystals CNCs were isolated from the fibers by means of acid hydrolysis while cellulose nanofibrils (CNFs) were isolated by combination of TEMPO-mediated oxidation and mechanical shearing using high-pressure homogenizer. The chemical composition of Ampelodesmos mauritanicus fibers was analyzed prior to the isolation of the different nanocellulose substrates in order to optimize their extraction processes. The morphology, geometry, and distribution of the cellulosic nanoparticles were performed using scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and the crystalline structure and the crystallite size were evaluated by X-ray diffraction (XRD). The surface charge of CNCs and the degree of oxidation of CNFs were examined by Zeta potential and conductometric titration. The nanocellulose substrates extracted from Ampelodesmos mauritanicus fibers exhibit a diameter of 5.64 ± 1.5 nm and length of 108.95 ± 13.7 nm for CNCs and 6.1 ± 1.5 nm and a few micrometers for CNFs. [ABSTRACT FROM AUTHOR]

The corrosion behavior of three used cooking oils and one non-edible fish oil was experimentally investigated by the immersion test of iron rods at room temperature. The corrosivity of the tested oils was indirectly determined from the amount of the dissolved iron in the tested oils after the immersion test. Different factors that affect the corrosive behavior of the tested oils were assessed. Among the tested oils, the fish oil showed the highest amount of dissolved iron owing to its chemical properties such as high water content and acid number. In general, water content and acid number have direct effects on the amount of dissolved iron. The addition of oleic acid to the used cooking oil resulted in a 60% less amount of dissolved iron. It was suggested that the addition of oleic acid prompted the formation of a monolayer, which inhibited the permeation of oxygen and water to the surface of the iron rod. Moreover, the addition of glycerol gave the lowest amount of dissolved iron in the oil sample owing to its ability to bind water molecules and form microemulsions in the presence of a surfactant (for example, oleic acid). [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrocracking of hexadecane to jet fuel components H- proton and metal Beta zeolites with different acidity. • Extensive catalyst characterization by physico-chemical methods. • Mildly acidic 2.5 wt% Ru-H-Beta-300 afforded 24% yield of the jet fuel components and 89% liquid mass balance closure. Hydrocracking of hexadecane to produce jet fuel components was investigated over proton and metal modified Beta zeolites with different acidity. They were characterized by a range of physico-chemical methods. The initial catalyst screening was performed at 210 °C under 40 bar hydrogen showing that the most promising catalysts were 2.5 wt% Pt-H-Beta-25 and 2.5 wt% Ru-H-Beta-300, which were also tested at 240 °C under 45 bar hydrogen. The results revealed that the yield of jet fuel components was maximally 27% over 2.5 wt% Pt-H-Beta-25. This catalyst gave, however, only 55% mass balance closure to the liquid phase products, while a mildly acidic 2.5 wt% Ru-H-Beta-300 afforded 24% yield of the jet fuel components and 89% liquid mass balance closure. [ABSTRACT FROM AUTHOR]