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Selective depolymerization of sugarcane bagasse to various xylose oligomers using a hybrid of plasma-acid treated activated carbon.

The utilisation of edible sources of starch such as corn, wheat, potato, and cassava has become the common approach to develop biodegradable food packaging. However, the future food security issue from the wide application of such edible starch sources has become a major concern. Consequently, exploring non-edible sources of starch for starch-based biodegradable food packaging and their property enhancement have become one of the common research interests. Although there has been a great potentials of synthesising biodegradable food packaging by direct utilisation of agro-industrial waste cassava bagasse, there have been very limited studies on this. In this context, the current study investigated the potential of developing biodegradable food packaging by directly using cassava bagasse as an alternative matrix. Two film-forming mixtures were prepared by incorporating glycerol (30% and 35%), powdered cassava bagasse and water. The films were hot-pressed at 60 °C, 100 °C, and 140 °C temperatures under 0.28 t pressure for 6 min. The best film-forming mixture and temperature combination was further tested with 0.42 t and 0.84 t pressures, followed by analysing their morphology, functional group availability and the thermal stability. Accordingly, application of 35% glycerol, with 100 °C, 0.42 t temperature and pressure, respectively, were found to be promising for film preparation. The absence of starch agglomerates in film surfaces with less defects suggested satisfactory dispersion and compatibility of starch granules and glycerol. The film prepared under 0.42 t exhibited slightly higher thermal stability. Synthesised prototypes of food packaging and the obtained characterisation results demonstrated the high feasibility of direct utilisation of cassava bagasse as an alternative, non-edible matrix to synthesise biodegradable food packaging.

A lactic acid/chlorine chloride-based deep eutectic solvent (DES) was used for the extraction of high-purity lignin (up to 94.7 %) in high yield (up to 75 %) from the hydrolysis/fermentation residue corn stover hydrolysate (CSH), which was generated from a pilot-plant-scale biorefinery. A range of extraction conditions were investigated, which involved varying reaction temperature, time, and DES composition. The relationship between lignin yield, purity, and structural characteristics with DES treatment conditions was determined. The extraction of high-purity lignin from hydrolysis/fermentation residues presents a promising approach for enhancing the economic feasibility of a lignocellulose biorefinery. It was also determined that DES extraction can produce lignin with a controlled range of molecular weight and functional group content.

In the time of rapidly depleting petroleum resources, worldwide food shortages, and solid waste problems, it is imperative to promote dedicated research into using an appropriate pretreatment technique utilizing regeneratable raw materials such as lignocellulosic biomass. However, not all pretreatment techniques are viable alternatives for industrial practice. Pretreatment is an important step to upgrade different kinds of lignocellulosic biomass into more valuable products, including biofuels and bio-based industrial chemicals. Most of the pretreatment techniques have their limitations or weaknesses, including high operational costs and temperature, toxicity and corrosiveness to the instrument, etc., while, some other pretreatment methods such as biological and plasma pretreatment are green procedures that can also be used to alter the physical and chemical properties of lignocellulosic materials. Although our present understanding is still low and not much research has been done to guarantee which pretreatment method is the reliable alternative, the combination of different pretreatment methods could be a good strategy to overcome the limitations of each approach. This review presents an overview of different pretreatment methods of lignocellulosic biomass to increase the rate and the degree of cellulose hydrolysis and subsequent processing steps as well as future perspectives.

14 páginas.- 12 figuras.- 2 tablas.- 68 referencias.- Supplementary data related to this article can be found at https://doi.org/10.1016/j.jclepro.2022.132404, We have examined a sustainable biorefinery process for the conversion of cotton gin trash (CGT), a waste from the cotton industry to multiple high value products. Herein, we found CGT native lignin to have unique features as it not only contains the p-hydroxyphenyl (H), guaiacol (G) and syringol (S) units, but structures of flavonoids, tyrosine, and phenylalanine associated with it. We have used the lignin-first approach to exploit its features in CGT and depolymerize it using argon gas and ethanol over Pd/C. The results show that 50% of the bio-aromatics is trans-isoeugenol, a precursor to produce vanillin. The cleavage of N-compounds from CGT during the fractionation process follows similar path as the rate of formation of the bio-aromatics. CGT impurities were shown to affect the reusability of the Pd/C catalyst. The fractionated cellulose-rich portion of CGT was converted to 39 mol% (80% purity) of 5-chloromethylfurfural (CMF), and a solid fuel which has a higher heating value of 20 MJ kg−1. The liquid extract, removed prior to CGT processing, was hydrogenated to produce C13–C17 liquid hydrocarbons, and the solid extract rich in nutrients is suitable for crops and plants growth. © 2022

The effect of pretreatment of sugarcane juice and juice composition on the performance of a ceramic membrane with pore size of 20 nm has been studied. Pretreatment options assessed included heating juice (60, 75 and 90 °C) with and without sedimentation at specified pHs (7.2, 7.5 and 7.8) and using evaporator supply juice (ESJ). The average permeate flux at 75 °C and pH 7.8 for limed juice, and partially clarified juice, and ESJ were 278 L/m2h, 248 L/m2h and 160 L/m2h in that order. It was shown that with ESJ, where the juice is boiled, there are higher proportions of crystalline and microcrystalline phases, and other impurities which reduces the efficiency of the membrane filtration process as the cake resistance (1.17 × 1012/m) is 1.7 times higher than of the partially clarified juice. With respect to the juice quality, the results of the permeate derived from the partially clarified juice at 75 °C, show that the lowest pH value of 7.2 gave the largest impurity reduction, though liming at pH 7.5 would be the preferred treatment for industrial application because of pH drop during processing. The fouling mechanism for the partially clarified juice was shown to be the combined cake filtration-complete blocking model.

An integrated microbial oil production process consisting of acidified glycerol pretreatment of sugarcane bagasse, enzymatic hydrolysis, microbial oil production by Mortierella isabellina NRRL 1757 and oil recovery by hydrothermal liquefaction (HTL) of fungal biomass in fermentation broth was assessed in this study. Following pretreatment, the effect of residual pretreatment hydrolysate (containing glycerol) on enzymatic hydrolysis was firstly studied. The residual pretreatment hydrolysate (corresponding to 2.0–7.5% glycerol) improved glucan enzymatic digestibilities by 10–11% compared to the enzymatic hydrolysis in water (no buffer). Although residual pretreatment hydrolysate at 2.0–5.0% glycerol slightly inhibited the consumption of glucose in enzymatic hydrolysate by M. isabellina NRRL 1757, it did not affect microbial oil production due to the consumption of similar amounts of total carbon sources including glycerol. When the cultivation was scaled-up to a 1 L bioreactor, glucose was consumed more rapidly but glycerol assimilation was inhibited. Finally, HTL of fungal biomass in fermentation broth without any catalyst at 340 °C for 60 min efficiently recovered microbial oils from fungal biomass and achieved a bio-oil yield of 78.7% with fatty acids being the dominant oil components (∼89%). HTL also led to the hydrogenation of less saturated fatty acids (C18:2 and C18:3) to more saturated forms (C18:0 and C18:1).

The removal of deposits from heat exchangers is one of the biggest challenges facing many food and chemical industries. Sodium hydroxide and acid cleaning are generally used on a regular basis to remove composite scale deposits from sugarcane factories. This paper evaluates the use of Fourier Transform Infrared (FTIR) spectroscopy, X-ray fluorescence, X-ray powder diffraction and 29Si nuclear magnetic resonance (NMR) to study the composition and the structural features of residual solid after NaOH treatment and use a second treatment of ethylene diamine tetraccetic acid tetra sodium salt (Na4EDTA) or dilute HCl to unravel the transformations of silica. There is no evidence of strong association between the silica matrix and the oxalates, or calcium carbonate components, but the use of dilute HCl resulted in the formation of complex and intractable Q3 [(OH)*Si(OSi)3] and Q4 [*Si(OSi)4] species as a consequence of re-organization/repolymerization processes. On the contrarily, the use Na4EDTA resulted in the formation of the simpler Q0 [Si(OH)4] `and Q1 [(OH)3*Si(OSi)] species. However, when the deposit contains a high proportion of hydroxyapatite (Ca5(PO4)3OH), HCl is more effective than Na4EDTA. When a cleaning regime involves a two-step process the order of addition is important for effective removal of deposits.

9 páginas.-- 8 figuras.-- 2 tablas.-- 35 referencias.-- The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acssuschemeng.7b02721, Catalytic depolymerization of organosolv lignin to phenolic monomers with zeolites was investigated under various operating conditions. H-USY (Si/Al molar ratio = 5) outperformed H-USY with Si/Al ratios of 50 and 250, H-BEA, H-ZSM5, and fumed SiO2 to produce the highest phenolic monomer yield from a commercial organosolv lignin in methanol at 300 °C for 1 h. It was then further investigated in the presence of acetone, ethyl acetate, methanol, and methyl isobutyl ketone (MIBK) on the depolymerization of organosolv bagasse lignin (BGL). The total highest phenolic monomer yield of 10.6 wt % was achieved with MIBK at 350 °C for 1 h with a catalyst loading of 10 wt %. A final total phenolic monomer yield of 19.4 wt % was obtained with an initial H2 pressure of 2 MPa under similar processing conditions. The main phenolic monomers obtained are guaiacol (7.9 wt %), 4-ethylphenol (6.0 wt %), and phenol (3.4 wt %). The solvent properties were used to account for the differences in phenolic monomer yields obtained with different organic solvents., The authors express their sincere appreciation to the Joint raduate School of Energy and Environment (JGSEE), Petchra Pra Jom Klao Doctoral Scholarship, King Mongkut’s University of Technology Thonburi (KMUTT), Thailand Research Fund (RTA5980006), and the Queensland University of Technology (QUT), Australia, for financing this project. The authors thank Dr. Jorge Rencoret and Dr. Ana Gutierrez, who were partly funded by the Spanish projects AGL2014-53730-R and CTQ2014-60764-JIN (cofinanced by FEDER funds), for PyGC/MS analysis of the lignins.

For second-generation (2 G) cellulosic ethanol production to be sustainable and viable, there is the need to value-add to the stillage. Here, pilot plant-derived 2G ethanol sugarcane bagasse stillage (BS) and eucalyptus stillage (ES) was transformed into valuable products using hydrothermal liquefaction (HTL) at 300 °C and 20 bar with Pd/C and K2CO3. BS produced oil, phenolic monomers, and organic acid yields of 32 %, 49 % and 25 % respectively, while yields for ES were lower. Catechol constituted 43 % of the total phenolic content for BS. Recycling the aqueous phase (containing acetic, formic, lactic, and propionic acids) improved phenol, guaiacol and catechol yields. Oil stability tests indicated a significant drop in oil yield with aging, but there was no significant change in higher heating value. A preliminary techno-economic analysis suggests that the potential value of producing 2G ethanol and products (including fertilizer) from BS is three times that of depithed sugarcane bagasse. This study demonstrated a potential technology to convert 2 G cellulosic ethanol stillage to value-added chemicals, which not only improved the efficiency and profitability of 2G ethanol production but reduced organic contaminants synthesis.

The hydroxycinnamic acids (HCAs), caffeic acid (CaA), p-coumaric acid (pCoA) and ferulic acid (FeA) are the main phenolic acid colour precursors present in sugar cane juice. The Fenton oxidative degradation products of these HCAs and mixture using Fe2+/H2O2 at pH 4.72 at 25 °C were identified using chromatography and mass spectrometry techniques. Oxalic (≤14 wt%), isobutyric (≤13.5 wt%) and formic acids (≤1.3 wt%) were the main organic acids formed. CaA produced the highest proportion of oxalic and isobutyric acids, while FeA produced the highest proportion of formic acid. The presence of increased proportion of oxalic acid in juice will increase the proportion of calcium oxalate scale in sugar mill heat exchangers. The phenolic-based products identified include protocatechuic aldehyde and 4-hydroxybenzoic acid and the basic phenols, p-allyphenol, p-vinylguaiacol, trans-isoeugenol, which when present in juice may react with juice constituents to increase juice colour in subsequent processing.

Fouling of industrial heat exchangers and evaporators is not only associated with energy management but also reductions in heat transfer coefficients causing loss in productivity. This paper describes the effect of NaOH solution on the removal of sugarcane factory heat exchanger deposits. Apatite, calcium oxalate, calcite, quartz, tricalcium aconitate and non-diffracting materials including amorphous silica are present in the deposits. Fourier Transform Infra-red (FTIR) spectroscopy revealed that monomeric silica species were preferential removed over oligomeric and polymeric species, while 29 Si nuclear magnetic resonance (NMR) analysis not only confirmed this, but identified the types of silica units Q 0 [Si(OH) 4 ], Q 1 [(OH) 3 *Si(OSi)], Q 2 [(OH 2 *Si(OSi) 2 ], Q 3 [(OH)*Si(OSi) 3 ] and Q 4 [*Si(OSi) 4 ] present, rearranged, and removed. After chemical cleaning, the scale components became truncated with indentation and contain spherical and hairy-like micro-sized particles. Also, the morphology of tetragonal CaCO 4 ·2H 2 O was found to be distorted and the proportion of crystalline phases decreased through fragmentation of the scale matrix.

As promising alternatives to fossil-derived oils, microbial lipids are important as industrial feedstocks for biofuels and oleochemicals. Our broad aim is to increase lipid content in oleaginous yeast through expression of lipid accumulation genes and use Saccharomyces cerevisiae to functionally assess genes obtained from oil-producing plants and microalgae. Lipid accumulation genes DGAT (diacylglycerol acyltransferase), PDAT (phospholipid: diacylglycerol acyltransferase), and ROD1 (phosphatidylcholine: diacylglycerol choline-phosphotransferase) were separately expressed in yeast and lipid production measured by fluorescence, solvent extraction, thin layer chromatography, and gas chromatography (GC) of fatty acid methyl esters. Expression of DGAT1 from Arabidopsis thaliana effectively increased total fatty acids by 1.81-fold above control, and ROD1 led to increased unsaturated fatty acid content of yeast lipid. The functional assessment approach enabled the fast selection of candidate genes for metabolic engineering of yeast for production of lipid feedstocks.

Achieving the goal of living in a sustainable and greener society, will need the chemical industry to move away from petroleum-based refineries to bio-refineries. This aim can be achieved by using biomass as the feedstock to produce platform chemicals. A platform chemical, 2,5-furandicarboxylic acid (FDCA) has gained much attention in recent years because of its chemical attributes as it can be used to produce green polymers such polyethylene 2,5-furandicarboxylate (PEF) that is an alternative to polyethylene terephthalate (PET) produced from fossil fuel. Typically, 5-(hydroxymethyl)furfural (HMF), an intermediate product of the acid dehydration of sugars, can be used as a precursor for the production of FDCA, and this transformation reaction has been extensively studied using both homogeneous and heterogeneous catalysts in different reaction media such as basic, neutral, and acidic media. In addition to the use of catalysts, conversion of HMF to FDCA occurs in the presence of oxidants such as air, O2, H2O2, and t-BuOOH. Among them, O2 has been the preferred oxidant due to its low cost and availability. However, due to the low stability of HMF and high processing cost to convert HMF to FDCA, researchers are studying the direct conversion of carbohydrates and biomass using both a single- and multi-phase approach for FDCA production. As there are issues arising from FDCA purification, much attention is now being paid to produce FDCA derivatives such as 2, 5-furandicarboxylic acid dimethyl ester (FDCDM) to circumvent these problems. Despite these technical barriers, what is pivotal to achieve in a cost-effective manner high yields of FDCA and derivatives, is the design of highly efficient, stable, and selective multi-functional catalysts. In this review, we summarize in detail the advances in the reaction chemistry, catalysts, and operating conditions for FDCA production from sugars and carbohydrates.

Pyrolytic bio-oils derived from renewable organic wastes are credible second-generation biofuels. In crude form, bio-oils are inherently complex mixtures that largely limit their direct application as fuels and integration into existing petroleum infrastructure, without additional upgrading. Herein, we report on low-oxygenated biofuel production from milk processing sludge using a multistage process configuration. In the first stage, bio-oil yields were maximised (57.7%) under slow pyrolysis conditions at 450 °C. Bio-oils were enriched in aliphatic hydrocarbons (19–22% alkanes), (11–14% alkenes) and alkyl nitriles (57–63%), while aromatics remained low at 450 °C) was not beneficial to bio-oil yields, reduced hydrocarbon contents and increased heteroatoms (O, S, N). In the second stage, sulphided Ni-Mo/Al2O3 catalysed hydroprocessing and distillation upgrading of bio-oils generated 100% C8-C22 saturated alkane distillates. With regard to fuel properties, oxygenation (0.26–0.89%), viscosities (4–6 mm2/s) and densities (ca.0.82 g/cm3) were comparable to standard diesel fuels. Resultant HHV (46.24 MJ/kg) and cetane index (69) of distillates produced from 450 °C bio-oils far exceeded those of diesel fuel standards, demonstrating direct fuel application and petroleum fuel compatibility.

This paper investigates the carbonization of cotton gin trash (CGT) into carbon structures shaped under the influence of different operating conditions including the impact of endogenous fatty acids impurities present in CGT. As expected, both KOH activation and high carbonization temperature increase the material surface area and porosity. Furan and arene groups are formed from 400 °C to 800 °C but the proportion of the furan groups are highest at 600 °C. This is due to the conversion of the fatty acids in CGT to furan units. XRD data reveals the presence of three aromatic layers at 400 °C, followed by structural rearrangement to the formation of five stacks aromatic layers at 800 °C consisting mainly of protonated and non-protonated condensed arene groups. Interestingly, a reduction in the number of aromatic structures is observed if no acid pretreatment of CGT to remove inorganic impurities is conducted prior to pyrolysis to 600 °C. Two potential applications of the synthesised carbons are shown; one for the formation of 5-hydroxymethylfurfural (80%) from fructose, which compares favorably to other porous carbon materials produced under harsher conditions, and another derived CGT carbon material which shows a good uptake of hydrogen for storage.

Settling, dewatering and filtration of flocs are important steps in industry to remove suspended solids and improve subsequent processing of the aqueous system. The influence of non-sucrose impurities (Ca 2+ , Mg 2+ , phosphate and aconitic acid) on the calcium phosphate floc structure (scattering exponent, S f ), size and shape were examined in synthetic and authentic sugar juices using X-ray diffraction techniques. In synthetic juices, S f decreases with increasing phosphate concentration to values where loosely bound and branched flocs are formed. These types of flocs are effective for the removal of suspended colloidal particles. Ca 2+ and Mg 2+ ions, and aconitic acid did not affect S f increasing concentration, although the floc size significantly decreased with increasing aconitic acid concentration, thereby reducing the ability of the flocs to remove particles. In authentic juices, the flocs structures were marginally affected by increasing proportions of non-sucrose impurities. However, optical microscopy indicated the formation of well-formed macro-floc network structures in sugar cane juices containing lower proportions of non-sucrose impurities. These structures are better placed to remove suspended particles in sugar solutions.

Acid-catalysed crude glycerol (ACG) pretreatment was carried out at 110 °C and 130 °C for mild fractionation of sugarcane bagasse into fermentable sugars and high-quality lignin. ACG pretreatment at 110 °C led to sugar yields of 71%-74%, comparable to those with acid-catalysed reagent-grade glycerol (AG). ACG pretreatment removed more lignin (53%-75%) than AG pretreatment (38%-49%), likely due to the presence of organic impurities in ACG. Hence, 28% more lignin was recovered from ACG pretreatment hydrolysate than with the AG pretreatment. NMR analysis revealed that recovered lignin was modified by glycerol through etherification of β-aryl ethers and esterification of hydroxycinnamic acids, which prevented lignin condensation and led to the generation of β-O-4 linkage-rich lignin at mild conditions (110 °C for 3 h and 5 h). This study suggests that crude glycerol is a suitable low-cost solvent for mild fractionation of lignocellulosic biomass into fermentable sugars and high-quality lignin for value-adding applications.

An integrated microbial oil production process consisting of acidified glycerol pretreatment of sugarcane bagasse, enzymatic hydrolysis, microbial oil production by

A one-step thermal extrusion process has been investigated for the modification of starch with alcohol in order to improve the film properties. Unmodified starch/glycerol mixtures containing Methanol (MetOH), ethanol (EtOH) and their combinations (5, 10 and 15 wt%) were thermally extruded to produce thermoplastic. The final hot-pressed film showed increased stiffness and crystallinity, while having decreased moisture uptake due to oxidation and alcohol complexing molecular interactions. The Young’s Modulus, tensile strength and elongation at break increased by 60%, 15% and 32% respectively, for 5 wt% MetOH derived film, compared to the control. The film moisture content was reduced by up to 15 wt% for 5 wt% EtOH-derived film. Generally the crystallinity increased in the alcohol-derived films due to an increased complexing of alcohol with starch forming the VH polymorph. Fourier transform infra-red (FTIR) and proton nuclear magnetic resonance (1HNMR) spectroscopic analysis were used to discuss the molecular interactions between the starch and alcohol molecules.

10 páginas.-- 5 figuras.-- 10 tablas.-- 39 referencias.-- Electronic supplementary information (ESI) available. See DOI:10.1039/c6ra20081h, In this study, the effects of an alkali-acid purification process on the properties of eucalyptus lignin isolated from a methyl isobutyl ketone (MIBK)/methanol/water-based organosolv fractionation process were evaluated. The results showed that the treatment reduced the content of carbohydrates, ash, nitrogen and sulfur, and improved lignin solubility (up to 218%) in five organic solvents (acetone, methanol, ethanol, tetrahydrofuran and dimethyl sulfoxide) and removed lignin fractions with smaller molecular weights. However, analysis by Py-GC/MS, solid state NMR and 2D-HSQC NMR indicated that the alkali-acid treatment process did not cause changes to the monomeric lignin subunits and linkages of the lignin polymer. The treated lignin showed slightly higher thermal stability at temperatures, We would also like to express our sincere appreciation of the Royal Golden Jubilee scholarship (RGJ) (Thailand), Thailand Research Fund (Thailand), and Queensland University of Technology (QUT, Australia) for financing this project.

Chloromethylfurfural (CMF), a valuable intermediate for the production of chemicals and fuels, can be derived in high yields from the cellulose component of biomass. This study examined the effect of sugarcane bagasse components and biomass architecture on CMF/bio-oil yield using a HCl/dichloroethane biphasic system. The type of pretreatment affected bio-oil yield, as the CMF yield increased with increasing glucan content. CMF yield reached 81.9% with bagasse pretreated by acidified aqueous ionic liquid, which had a glucan content of 81.6%. The lignin content of the biomass was found to significantly reduce CMF yield, which was only 62.3% with an acid-catalysed steam exploded sample having a lignin content of 29.6%. The change of CMF yield may be associated with fibre surface changes as a result of pretreatment. The hemicellulose content also impacted negatively on CMF yield. Storage of the bio-oil in chlorinated solvents prevented CMF degradation.

Simple lignin model compounds containing β-O-4 aryl ether linkages have been utilized as a means to understand lignin depolymerisation. The effects of reaction temperature, time, catalyst concentration, and initial phenethoxybenzene (PEB) concentration on the degradation of PEB in NaOH were investigated. Operating at 300 °C for 1 h resulted in the highest combined yield of the primary products, phenol and styrene, and also resulted in a reduced amount of degradation products formed. The proportion of oligomeric and polymeric materials formed depended on the NaOH concentration, but not on the initial PEB concentration for equal reaction time. The results were used to suggest probable reaction pathways for PEB degradation.

Recently, second-generation (non-vegetable oil) feedstocks for biodiesel production are receiving significant attention due to the cost and social effects connected with utilising food products for the production of energy products. The Beauty leaf tree (Calophyllum inophyllum) is a potential source of non-edible oil for producing second-generation biodiesel because of its suitability for production in an extensive variety of atmospheric condition, easy cultivation, high fruit production rate, and the high oil content in the seed. In this study, oil was extracted from Beauty leaf tree seeds through three different oil extraction methods. The important physical and chemical properties of these extracted Beauty leaf oils were experimentally analysed and compared with other commercially available vegetable oils. Biodiesel was produced using a two-stage esterification process combining of an acid catalysed pre-esterification process and an alkali catalysed transesterification process. Fatty acid methyl ester (FAME) profiles and important physicochemical properties were experimentally measured and estimated using equations based on the FAME analysis. The quality of Beauty leaf biodiesels was assessed and compared with commercially available biodiesels through multivariate data analysis using PROMETHEE-GAIA software. The results show that mechanical extraction using a screw press produces oil at a low cost, however, results in low oil yields compared with chemical oil extraction. High pressure and temperature in the extraction process increase oil extraction performance. On the contrary, this process increases the free fatty acid content in the oil. A clear difference was found in the physical properties of Beauty leaf oils, which eventually affected the oil to biodiesel conversion process.However, Beauty leaf oils methyl esters (biodiesel) were very consistent physicochemical properties and able to meet almost all indicators of biodiesel standards. Overall this study found that Beauty leaf is a suitable feedstock for producing second-generation biodiesel in commercial scale.Therefore, the findings of this study are expected to serve as the basis for further development of Beauty leaf as a feedstock for industrial scale second-generation biodiesel production.

Sugar cane biomass is one of the most viable feedstocks for the production of renewable fuels and chemicals. Therefore, processing the whole of crop (WC) (i.e., stalk and trash, instead of stalk only) will increase the amount of available biomass for this purpose. However, effective clarification of juice expressed from WC for raw sugar manufacture is a major challenge because of the amounts and types of non-sucrose impurities (e.g., polysaccharides, inorganics, proteins, etc.) present. Calcium phosphate flocs are important during sugar cane juice clarification because they are responsible for the removal of impurities. Therefore, to gain a better understanding of the role of calcium phosphate flocs during the juice clarification process, the effects of impurities on the physicochemical properties of calcium phosphate flocs were examined using small-angle laser light scattering technique, attenuated total reflectance Fourier transformed infrared spectroscopy, and X-ray powder diffraction. Results on synthetic sugar juice solutions showed that the presence of SiO2 and Na(+) ions affected floc size and floc structure. Starch and phosphate ions did not affect the floc structure; however, the former reduced the floc size, whereas the latter increased the floc size. The study revealed that high levels of Na(+) ions would negatively affect the clarification process the most, as they would reduce the amount of suspended particles trapped by the flocs. A complementary study on prepared WC juice using cold and cold/intermediate liming techniques was conducted. The study demonstrated that, in comparison to the one-stage (i.e., conventional) clarification process, a two-stage clarification process using cold liming removed more polysaccharides (≤19%), proteins (≤82%), phosphorus (≤53%), and SiO2 (≤23%) in WC juice but increased Ca(2+) (≤136%) and sulfur (≤200%).

Depolymerization of purified organosolv eucalyptus wood lignin by heterogeneous catalysts, cobalt polyphosphate (CoP2O6) and calcium phosphate (β-CaP2O6) was investigated. A total syringol yield of 16.7% was achieved with β-CaP2O6 in a methanol–water (50/50, w/w) solvent system after depolymerization at 300 °C for 1 h, showing the selectivity of the catalyst.

As promising alternatives to fossil-derived oils, microbial lipids are important as industrial feedstocks for biofuels and oleochemicals. Our broad aim is to increase lipid content in oleaginous yeast through expression of lipid accumulation genes and use Saccharomyces cerevisiae to functionally assess genes obtained from oil-producing plants and microalgae. Lipid accumulation genes DGAT (diacylglycerol acyltransferase), PDAT (phospholipid: diacylglycerol acyltransferase), and ROD1 (phosphatidylcholine: diacylglycerol choline-phosphotransferase) were separately expressed in yeast and lipid production measured by fluorescence, solvent extraction, thin layer chromatography, and gas chromatography (GC) of fatty acid methyl esters. Expression of DGAT1 from Arabidopsis thaliana effectively increased total fatty acids by 1.81-fold above control, and ROD1 led to increased unsaturated fatty acid content of yeast lipid. The functional assessment approach enabled the fast selection of candidate genes for metabolic engineering of yeast for production of lipid feedstocks.

10 páginas.-- 4 figuras.-- 3 tablas.-- 54 referencias.-- The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acssuschemeng.7b00274., Commercial furfural, an important platform chemical, is produced from acid hydrolysis of lignocellulosic biomass. The manufacturing processes are inherently inefficient, and so it is necessary to value add to substantial amounts of residue obtained. The structural features of bagasse furfural residue and the lignins extracted from it by three NaOH treatments have been studied in order to understand the transformations that occurred by these treatments. 2D-NMR and Py-GC/MS of the furfural residue revealed that it contains mostly lignin and depolymerized cellulose moieties and the complete absence of xylans as a result of their hydrolysis during the furfural production process. In addition, the analyses revealed that the furfural residue contains 44% of H-type lignin units, in comparison to 11% for bagasse, and most of the lignin interunit linkages present in bagasse have disappeared. The pyrograms show that the furfural residue produced unusually high phenol content, which was attributed to the high levels of “H-type” units present in this lignin. The proportion of functional groups, particularly total OH aliphatic groups, where significantly lower in the extracted lignins compared to soda lignin obtained by the normal pulping process. The highest severity of the NaOH extraction process reduced the amount of reactive functional groups present in the lignin, though the S/G ratios of ∼1.1 were independent of the extraction method. The three lignins have high proportions of “H-units” (around 36–37%), which gives them special properties for different applications, particularly in the production of phenolic resins., This study was partly funded by Sugar Research Australia, formerly Sugar Research Development Corporation (QUT004). JoséC. del Rio, Jorge Rencoret, and Ana Gutierrez were partially funded by the Spanish projects AGL2014-53730-R and CTQ2014-60764-JIN (cofinanced by FEDER funds)

Sugarcane bagasse pretreatment processes using acidified aqueous ethylene glycol (EG) and ionic liquids (ILs) have been reported recently. In this study, recovery of lignins from these processes was conducted, as well as determination of their physico-chemical properties. The amount of lignins recovered from 1-butyl-3-methylimidazolium chloride ([bmim]Cl) with HCl as a catalyst and [bmim][CH3SO3] was ∼42%, and ∼35%–36% by EG with HCl or H2SO4 as a catalyst, respectively. The isolated lignins were characterised using wet chemistry, spectroscopy and thermogravimetry analysis (TGA), and the results compared to soda lignin from NaOH pretreatment of bagasse. The IL and EG lignins contained no or trace amounts of carbohydrates, slightly lower hydrogen content but slightly higher oxygen contents than soda lignin. The IL and EG lignins contained more C-3 and C-5 reactive sites for Mannich reaction and had more p-hydroxypheny propane unit structures than soda lignin. Two-dimensional heteronuclear single quantum coherence (2D HSQC) nuclear magnetic resonance (NMR) identified the major substructural units in the lignins, and allowed differences among them to be studied. As EG lignins were extracted in very reactive environment, intermediate enol ethers were formed and led to cleavage reactions which were not apparent in the other lignins. 31P NMR and infra-red spectroscopy results showed that IL and EG lignins had lower total hydroxyl content than soda lignin, probably indicating that a higher degree of self-polymerisation occurred during bagasse pretreatment, despite the use of lower temperature and shorter reaction time. On the basis of the salient features of these lignins, potential applications were proposed.

This paper reports on the results of using unbleached sugar cane bagasse nanofibres (average diameter 26.5 nm; aspect ratio 247 assuming a dry fibre density of 1,500 kg/m3) to improve the physico-chemical properties of starch-based films. The addition of bagasse nanofibres (2.5 to 20 wt%) to modified potato starch (i.e. soluble starch) reduced the moisture uptake by up to 17 % at 58 % relative humidity. The film’s tensile strength and Young’s modulus increased by up to 100 % (3.1 to 6.2 MPa) and 300 % (66.3 to 198.3 MPa) respectively with 10 and 20 wt% fibre addition. However, the strain at yield dropped by 50 % for the film containing 10 wt% fibre. Models for composite materials were used to account for the strong interactions between the nanofibres and the starch matrix. The storage and loss moduli as well as the glass transition temperature (Tg) obtained from dynamic mechanical thermal analysis, were increased with the starch-nanofibre films indicating decreased starch chain mobility due to the interacting effect of the nanofibres. Evidence of the existence of strong interactions between the starch matrix and the nanofibres was revealed from detailed Fourier transform infra-red and scanning electron microscopic evaluation.

The adsorption of Congo Red (CR) by ball-milled sugarcane bagasse was evaluated in an aqueous batch system. CR adsorption capacity increased significantly with small changes in bagasse surface area. CR removal decreased with increasing solution pH from 5.0 to 10.0. Maximum adsorption capacity was 38.2 mg/g bagasse at a CR concentration of 500 mg/L. The equilibrium isotherm fitted the Freundlich model and the adsorption kinetics obeyed pseudo-second order equation. CR adsorption obeyed the intra-particle diffusion model very well with bagasse surface area in the range of 0.58–0.66 m2/g, whereas it was controlled by multi-adsorption stages with bagasse surface area in the range of 1.31–1.82 m2/g. Thermodynamic analysis indicated that the adsorption process is an exothermic and spontaneous process. Fourier transform infrared analysis of bagasse containing adsorbed CR indicated interactions between the carboxyl and hydroxyl groups of bagasse and CR function groups.

A laboratory scale twin screw extruder has been interfaced with a near infrared (NIR) spectrometer via a fibre optic link so that NIR spectra can be collected continuously during the small scale experimental melt state processing of polymeric materials. This system can be used to investigate melt state processes such as reactive extrusion, in real time, in order to explore the kinetics and mechanism of the reaction. A further advantage of the system is that it has the capability to measure apparent viscosity simultaneously which gives important additional information about molecular weight changes and polymer degradation during processing. The system was used to study the melt processing of a nanocomposite consisting of a thermoplastic polyurethane and an organically modified layered silicate.

12 páginas.-- 6 figuras.-- 6 tablas.-- 52 referencias.-- The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acssuschemeng.6b01093., Dilute acid pretreatment is one of the most studied biomass deconstructing technologies due to its relatively low process cost. Typical cellulosic ethanol production process involves three main stages: (1) dilute acid pretreatment, (2) enzymatic hydrolysis, and (3) fermentation/distillation. In this study, three lignins, L1, L2, and L3, were extracted using 1% (w/w) NaOH solution at 80 °C following each stage, respectively. Lignin characterization shows the reduction of aliphatic, guaiacyl, and carboxylic OH groups of the L2 and L3 compared to those of the L1 but increases in both the weight and number molecular weights as well as slight increases in the polydispersity index, probably because, among other reasons, of the removal of a higher molecular weight lignin fraction from the pretreated biomass during enzymatic hydrolysis. While 2D HSQC NMR and Py-GC/MS did not reveal differences in the proportions of syringyl and p-hydroxyphenyl units among the lignins, there is a predominance of the phenylcoumaran substructures and guaiacyl lignin units in L1 and the absence of some substructures/linkages associated with L2 and L3. Lignin extraction following dilute acid pretreatment not only produced the lignin with the highest purity but also resulted in improved glucose yield from 71% to 77%., This study was partly funded by the Australian Indian Strategic Research Fund (AISRF) Grand Challenge Project (GCF020010). Jose Rio, Jorge Rencoret, and Ana Gutierrez who conducted the analytical pyrolysis work were partially funded by the Spanish projects AGL2014-53730-R and CTQ2014-60764-JIN (cofinanced by FEDER funds).

Global climate change, increasingly erratic weather and a burgeoning global population are significant threats to the sustainability of future crop production. There is an urgent need for the development of robust measures that enable crops to withstand the uncertainty of climate change whilst still producing maximum yields. Resurrection plants possess the unique ability to withstand desiccation for prolonged periods, can be restored upon watering and represent great potential for the development of stress tolerant crops. Here, we describe the remarkable stress characteristics of Tripogon loliiformis, an uncharacterised resurrection grass and close relative of the economically important cereals, rice, sorghum, and maize. We show that T. loliiformis survives extreme environmental stress by implementing autophagy to prevent Programmed Cell Death. Notably, we identified a novel role for trehalose in the regulation of autophagy in T.loliiformis. Transcriptome, Gas Chromatography Mass Spectrometry, immunoblotting and confocal microscopy analyses directly linked the accumulation of trehalose with the onset of autophagy in dehydrating and desiccated T. loliiformis shoots. These results were supported in vitro with the observation of autophagosomes in trehalose treated T. loliiformis leaves; autophagosomes were not detected in untreated samples. Presumably, once induced, autophagy promotes desiccation tolerance in T.loliiformis, by removal of cellular toxins to suppress programmed cell death and the recycling of nutrients to delay the onset of senescence. These findings illustrate how resurrection plants manipulate sugar metabolism to promote desiccation tolerance and may provide candidate genes that are potentially useful for the development of stress tolerant crops., Author Summary Over coming decades, climate change models suggest that droughts and other unpredictable weather patterns will appear more frequently. It is imperative that we develop crops that can survive future climates but continue to yield. Numerous studies have shown that stress tolerance is genetically encoded. Naturally tolerant species therefore represent an ideal starting point for the search for stress tolerance. Resurrection plants belong to a small group of vascular plants that possess unique stress tolerance mechanisms to withstand extreme desiccation with the ability to recover fully upon the availability of water. Here we describe a unique regulatory role for trehalose in the activation of autophagy pathways in T.loliiformis. We show that T. loliiformis leaves are alive in desiccated plants and that pre-existing tissues resurrect upon the addition of water. By using a combination of transcriptomics, confocal microscopy and spectroscopy we show that autophagy is induced during dehydration. Notably, we establish that treatment of leaves with trehalose triggers autophagy in vitro and that trehalose accumulation in dehydrating leaves correlates with the presence of autophagosomes. We postulate that resurrection plants modulates trehalose metabolism to induce and maintain autophagy pathways that preventing senescence and programmed cell death.