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This study assesses the possibility of obtaining regenerated cellulose products (beads and films) from eucalyptus sawdust dissolving pulps produced by non-conventional processes, compared with a commercial dissolving pulp as a reference. Eucalyptus sawdust dissolving pulps were obtained by soda pulping followed by two different TCF sequential bleaching processes OOpZ and OOp (where O is oxygen, Op is oxygen reinforced with hydrogen peroxide, and Z is ozone), followed by a cold soda extraction. The characterization of dissolving pulps involved alpha-, beta- and gamma-cellulose content, alkali solubility with 10 wt% (S10), and 18 wt% NaOH (S18) aqueous solutions, and degree of polymerization. Fock´s method was used to measure cellulose reactivity and the alkali solubility in a 9 wt% NaOH aqueous solution at -5 °C to evaluate the pulps dissolving capacity. Dissolving pulps presented high cellulose content (> 93 %, expressed as a-cellulose) and good reactivity (almost 84 %). The dissolving pulps were adequate raw materials for regenerated cellulose products (beads and films) from two cellulose dissolution methods: direct dissolution in NaOH/urea and cellulose carbamate solution. The sequence OOpE (where E is an alkaline extraction) was determined to be a more economically feasible and straightforward process to produce dissolving pulp than OOpZE. The experimental pulps showed the expected characteristics of the dissolving pulp to obtain regenerated cellulose products. However, it is necessary to deepen the study of producing regenerated cellulose films with enhanced mechanical properties from experimental dissolving pulps, solvents, coagulation, and regeneration conditions.

The implementation of biorefineries of sawmill residues is an opportunity in countries or regions with a high rate of afforestation. Microfibrillated cellulose (MFC) is a high-value product that can be obtained from the cellulosic fraction. However, many critical aspects involved in its production and characterization are not clarified yet. This study analyzes the physical and morphological properties of laboratory-obtained MFC from different sources, among them, hardwood and softwood industrial pulps and unbleached pine sawdust pulps from conventional and non-conventional processes, aiming to evaluate and predict the relationship between the characteristics of the pulps and those of MFC. MFC dimensions and the properties of the MFC suspensions (viscosity, transmittance, others) were determined. The results showed that unbleached pine sawdust pulp is a low-cost and environmentally friendly raw material for MFC production and that this MFC can be produced with less energy and on a small scale than MFC from industrial pulps. A principal component analysis was assessed, showing that pine pulps from sawdust produce MFC of similar characteristics to conventional pine pulps from chips (high relative transmittance, short microfibrils, and small widths visible with the optical microscope), so fiber length of the original pulp is not so relevant than high fiber width and fiber coarseness.

Bio-based ethylene produced by bioethanol dehydration is an environmentally friendly substitute for oil-based ethylene. It is a low-pollution raw material that can be used to produce high-value bio-based materials. Currently, some industrial plants use first-generation (1G) bioethanol to produce bio-ethylene. However, second-generation (2G) bioethanol is not currently used to produce bio-ethylene because the manufacturing processes are not optimized. The conversion of lignocellulosic biomass to bio-ethylene involves pretreatment, enzymatic hydrolysis of carbohydrates, the fermentation of sugars to ethanol, ethanol recovery by distillation, and ethanol dehydration to ethylene. This work presents a review of second-generation (2G) bio-ethylene production, analyzing the stages of the process, possible derivatives, uses, and applications. This review also contains technical, economic, and environmental considerations in the possible installation of a biorefinery in the northeast region of Argentina (NEA).

The need to develop biobased materials from renewable feedstocks requires the previous design and assessment of the production processes of these promising new value-added products. Nano and micro- fibrillated cellulose (NFC and MFC, respectively) are two of these new products that could revolutionize the biobased industry. In the present work, the production of NFC and CMF was analyzed in a multiproduct biorefinery from eucalyptus sawdust. It was determined that it is possible to obtain 308 kg of NFC or MFC, 169 kg of xylose syrup, and about 220 kg of lignin per ton of dry sawdust. The investment required for the analyzed alternatives of NFC and MFC is between 40–44 million USD and the NPV values are between 30 and 60 million USD. The most attractive alternative is the production of NFC, xylose syrup, and lignin (alternative III of NFC). The most important production costs correspond to enzymes and energy (for NFC and MFC, respectively). Besides, it was determined that with the proposed schemes for a sawdust availability of

This work aims to evaluate second-generation bioethanol production from the soda-ethanol pulp of pine sawdust via two strategies: separate hydrolysis and fermentation and simultaneous saccharification and fermentation. A kinetics study of the enzymatic hydrolysis of separate hydrolysis and fermentation was included as a design tool. Three soda-ethanol pulps (with different chemical compositions), Cellic® Ctec2 cellulolytic enzymes, and Saccharomyces cerevisiae IMR 1181 (SC 1181) yeast were employed. The obtained kinetic parameters were as follows: an apparent constant (k) of 11.4 h-1, which represents the link frequency between cellulose and cellulase; a Michaelis-Menten apparent constant (KM) of 23.5 gL-1, that indicates the cellulose/cellulase affinity; and the apparent constant of inhibition between cellulose-glucose and cellulase (KI), which was 2.9 gL-1, 3.1 gL-1, and 6.6 gL-1 for pulps 1, 2, and 3, respectively. The kinetic model was applicable, since the calculated glucose values fit the experimental values. High bioethanol yields were obtained for pulp 3 in the separate hydrolysis and fermentation and simultaneous saccharification and fermentation processes (89.3% and 100% after 13 h and 72 h, respectively). Fil: Mendieta, Carolina Monica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Felissia, Fernando Esteban. Universidad Nacional de Misiones; Argentina Fil: Arismendy Pabón, Ana María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Kruyeniski, Julia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina

The differences between a biorefinery and an oil refinery are determined by the higher oxygen content of the biorefinery´s biomass, its high degree of functionalization, its low thermal stability, its polar components, which are mostly acidic, its highly heterogeneous structure, and its quality variation as result of genotypic and phenotypic characteristics. Levulinic acid (LA) is one of the main high value-added chemicals that can be produced from lignocellulosic biomass as raw material. The main challenges for the conversion of lignocellulosic biomass to levulinic acid are related to the improvement of the technologies to obtain a pure and cost-competitive product, the design and use of efficient heterogeneous catalysts, and the improvements in the selectivity and useful life of the catalyst. This is an up-to-date review of the state of knowledge about the heterogeneous catalytic conversion of biomass into LA, addressing the technical hurdles that impede the attainment of high yields. This work outlines the chemistry of LA synthesis and discusses in detail the influence of the lignocellulosic raw material, reaction time, temperature, solvent according to the chemical pathway, and efficiency of the chosen Lewis and Brønsted solid acid catalysts. Fil: Covinich, Laura Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Clauser, Nicolás Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Vallejos, María Evangelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina

There is a global trend of substitution of fossil fuels for renewable energy sources, which are preferred by reasons including sustainability, reduction of greenhouse gases that contribute to climate change, regional and social systems advancement, among others. This review is part of the studies carried out on the integral use of wood industrial wastes due to its low costs and high availability. A possible high-value product is ethylene, obtained by catalytic dehydration of second-generation bioethanol from lignocellulosic materials and which can be an effective alternative for the production of polymers such as polyethylene (PE), which is conventionally obtained from petroleum. Biobased polyethylene or biopolyethylene (BioPE) may potentially contribute to close a pine biorefinery scheme to obtain high-value products, using processes of low pollution and contributing to the global environmental balance. The process involves the following stages: pretreatment, enzymatic saccharification, fermentation, dehydration, and polymerization. This review includes the different processes for second generation (2G) bioethylene productions from pine wastes as an example and the technologies that can potentially be applied on an industrial scale for BioPE production, focusing on the catalytic dehydration of 2G bioethanol through the use of catalysts able to achieve high ethanol conversions and ethylene selectivity. Fil: Mendieta, Carolina Monica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Vallejos, María Evangelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Chinga-Carrasco, G.. Research Institutes of Sweden. PFI; Noruega Fil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina

This work proposes a sequential combination of steam explosion and organosolv delignification for Pinus radiata fractionation. An efficient pretreatment to fully optimize the use of lignocellulosic materials is the key to make a biorefinery profitable, especially for softwoods, known to be more recalcitrant than other lignocellulosic raw materials. Steam explosion has a dual effect on biomass as morphological and chemical changes are introduced. A delignifying stage has been stated to be necessary in order to ease hydrolytic enzymes accessibility to cellulose while avoiding non-productive bonds with the lignin present. Three steam explosion conditions were tested (170°C, 5 min; 180°C, 10 min; 170°C, 5+5 min) followed by an organosolv delignification stage, carried out at two different conditions (170°C, 60 min; 170°C, 90 min). All treatment yields, delignification extent, and hydrolysis yields were determined to evaluate each stage. The steam explosion treatment did not produce high delignification extent. Maximum global delignification (50.4%) was achieved when combining the two-cycle steam explosion with the most severe post-treatment condition tested. Enzymatic hydrolysis of the cellulosic residue improved after organosolv delignification; however, hydrolysis yields did not exceed 35%. The chemical changes undergone by softwood lignins are presumably responsible for the low digestibility. Fil: Imlauer Vedoya, Camila María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Vergara Alarcón, Priscila. Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria; España Fil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Revilla, Esteban. Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria. Centro de Investigación Forestal; España Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Villar, Juan Carlos. Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria. Centro de Investigación Forestal; España

The aim of this work was to evaluate the effect of different pretreatments applied to industrial slash pine sawdust (Pinus elliottii) on its enzymatic hydrolysis. NREL laboratory analytical procedures for standard biomass analysis were used to characterize the thirty one fibrous materials produced. Eight pretreated materials were selected considering both the chemical composition and the enzymatic hydrolysis yield to further evaluate crystallinity and porosity, determined by X-ray diffraction and thermoporosimetry, respectively. Diluted acid, steam explosion, and slight alkali treatments revealed to be not effective to enhance enzymatic hydrolysis of resinous pines since a maximum yield value of only 25% was achieved. On the contrary, strong alkali treatments promoted the lignin removal, thus increasing the accessibility of the material for enzymatic hydrolysis. In accordance, the highest values of the cellulose crystallinity (about 75?76%) were also obtained. No correlation was found between the porosity and the enzymatic hydrolysis yield. It was concluded that to enhance enzymatic hydrolysis the lignin content of the pretreated material should below. As for the hemicelluloses content, only its interaction with the lignin content is significant, as revealed by the regression model obtained. Fil: Kruyeniski, Julia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Ferreira, Paulo Jorge. Universidad de Coimbra; Portugal Fil: Carvalho, Maria da Graça Videira Sousa. Universidad de Coimbra; Portugal Fil: Vallejos, María Evangelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina

The soda–ethanol process was conceived as a sulfur-free pulping process, which may also be an alternative to conventional alkaline pulping, such as kraft or soda–AQ in the biorefinery context. An in-depth study using two experimental designs was conducted to establish the viability of soda–ethanol delignification of pine sawdust. At first, a simple factorial design involving the ethanol–water ratio (ethanol:water) and the alkaline load (AL, % over dry wood, odw) was applied to define the levels of these variables and their eventual interaction. Then, a 32 experimental design was performed to evaluate the ability of the process concerning the pulping of pine sawdust. The tested conditions were carefully selected to screen a broad range of cooking times (60, 100, and 140 min) and alkaline loads (19.0, 23.3, and 27.6 %odw) to obtain pulps with different extents of delignification (residual lignin contents). Finally, the kraft, soda–AQ, and soda–ethanol treatments were compared. Soda–ethanol pulping was shown to be a suitable delignification stage for a biorefinery scheme of Pinus elliottii and Pinus taeda sawdust. It has many advantages over traditional processes regarding its environmental impact, harmless chemicals, and selectivity. The tested conditions were similar to those frequently used in conventional pulping at an industrial scale, suggesting the technical feasibility of the soda–ethanol process for pine sawdust processing.

Polyhydroxyalkanoates (PHAs) are defined as natural and biodegradable biopolymers obtained by microbial synthesis. PHAs are classified as short chain length (3–5 carbon monomers), medium chain length (6–14 carbon monomers), and long chain length (15–18 carbon monomers), depending on the number of carbons in the monomeric constituents. Little is known about the biodegradation potential of PHAs in nature and how this can be tailored by adding complementary polymers and lignocellulosic components. In this chapter, we have reviewed the current literature with a focus on biocomposites based on PHAs and lignocellulosic materials. We also complemented this chapter with a case study, including recent results from our research activities within this area. Examples are provided on how lignocellulosic materials affected the mechanical properties of PHAs and increased the biodegradation rate in soil. We also explored the potential of 3D printing by fused deposition modeling as a novel technology to manufacture PHA-based products.

Bio-polyethylene (BioPE, derived from sugarcane), sugarcane bagasse pulp, and two compatibilizers (fossil and bio-based), were used to manufacture biocomposite filaments for 3D printing. Biocomposite filaments were manufactured and characterized in detail, including measurement of water absorption, mechanical properties, thermal stability and decomposition temperature (thermo-gravimetric analysis (TGA)). Differential scanning calorimetry (DSC) was performed to measure the glass transition temperature (Tg). Scanning electron microscopy (SEM) was applied to assess the fracture area of the filaments after mechanical testing. Increases of up to 10% in water absorption were measured for the samples with 40 wt% fibers and the fossil compatibilizer. The mechanical properties were improved by increasing the fraction of bagasse fibers from 0% to 20% and 40%. The suitability of the biocomposite filaments was tested for 3D printing, and some shapes were printed as demonstrators. Importantly, in a cradle-to-gate life cycle analysis of the biocomposites, we demonstrated that replacing fossil compatibilizer with a bio-based compatibilizer contributes to a reduction in CO2-eq emissions, and an increase in CO2 capture, achieving a CO2-eq storage of 2.12 kg CO2 eq/kg for the biocomposite containing 40% bagasse fibers and 6% bio-based compatibilizer.Keywords: bio-based filament; 3D printing; sugarcane bagasse pulp Fil: Ehman, Nanci Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Ita Nagy, Diana. Pontificia Universidad Católica de Perú; Perú Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Vallejos, María Evangelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Quispe, Isabel. Pontificia Universidad Católica de Perú; Perú Fil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Chinga Carrasco, Gary. Rise. Paper And Fibre Research Institute As; Noruega

The effect of the addition of nanofibers on the physical mechanical properties of industrial chemimechanical pulps was evaluated. The nanofibers were obtained from two commercial pulps produced by traditional treatments (bleached kraft pulp from pine chips and bleached soda-oxygen sugarcane bagasse pulp), and two experimental pulps from biorefinery schemes (unbleached soda/ethanol sawdust pulp and unbleached soda/oxygen sawdust pulp). The nanofibers (3 wt.%) were added to industrial pulps taken from two positions of the approach flow, trying to reproduce the real paper machine process. Significant correlations between the characteristics of the cellulose nanofibers and the drainability of pulp suspension and the physical-mechanical properties of handsheets were found. The increase in the degree of fibrillation decreased significantly the drainability of the pulp suspensions. Nanofibrillation yield, transmittance, viscosity at 0.5% consistency, and carboxylic content positively correlated with °SR. On the contrary, turbidity, and ξ-potential correlated negatively. Nanofiber incorporation increased Tensile Index (up to 21%), Burst Index (23-37%), E modulus (up to 17%), Concora Medium Test (up to 27%), Ring Crush Test (up to 28%), and Short-Span Compression Test values up to 23% in the handsheets where nanofibers from bleached kraft pulp were added. A positive correlation was found between the tensile index and nanofibrillation yield, and between E modulus and viscosity at 0.5% consistency for all pulps and a high linear relationship between both variables was found for nanofibers from pine pulps. Finally, the values of air permeability decreased up to 80% respect to the control. Fil: Ehman, Nanci Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Tarrés, Quim. Universidad de Girona; España Fil: Vallejos, María Evangelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Delgado Aguilar, Marc. Universidad de Girona; España Fil: Mutjé, Pere. Universidad de Girona; España Fil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina

This work proposes a kinetic model for the reactions involved in the heterogeneous copper-based Fenton-type oxidation of mixed recalcitrant compounds in a real industrial effluent from the alkaline sulfite treatment of wood. This kind of treatment is unusual in this industry due to the complexity of the effluents and the high costs involved in total mineralization of the organic matter. Nevertheless, conversion of recalcitrant to degradable compounds and catalyst recovery can make the difference. The complexity of the effluent and the great number of compounds formed as intermediates, make extremely difficult the identification and quantification of the individual reactions that occur during oxidation. To solve this drawback TOC parameter was used as a representative measurement. To verify the level of TOC degradation produced by the heterogeneous catalysis reaction, experiences of homogeneous catalysis and adsorption were accomplished. The studied temperature range was 45–80 °C. A “two-step” kinetic model was applied to TOC reduction in heterogeneous and homogeneous oxidations, admitting two sequential steps of oxidation: a first fast stage (“seconds stage”) followed by a slow one (“minutes stages”). Kinetic constants were obtained for both processes and activation energies were also determined for the “minutes stage” step (33.17 kJ/mol and 15.13 kJ/mol, respectively). Homogeneous catalysis studies confirm mass transfer limitations in heterogeneous oxidations. Experiences of adsorption of organic matter on CuO/γ-Al2O3 catalyst demonstrated that this phenomenon is exothermic and cannot be neglected. The activation energy of adsorption was determined as 7.32 kJ/mol. Catalysts were characterized through SEM, EDS, XRD, FTIR, and TGA. Graphical Abstract: [Figure not available: see fulltext.]. Fil: Covinich, Laura Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Massa, Paola Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Fenoglio, Rosa Juana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina

Bagasse is an underutilized agro-industrial residue with great potential as raw material for the production of cellulose nanofibrils (CNF) for a range of applications. In this study, we have assessed the suitability of bagasse for production of CNF for three-dimensional (3D) printing. First, pulp fibers were obtained from the bagasse raw material using two fractionation methods, i.e. soda and hydrothermal treatment combined with soda. Second, the pulp fibers were pretreated by TEMPO-mediated oxidation using two levels of oxidation for comparison purposes. Finally, the CNF were characterized in detail and assessed as inks for 3D printing. The results show that CNF produced from fibers obtained by hydrothermal and soda pulping were less nanofibrillated than the corresponding material produced by soda pulping. However, the CNF sample obtained from soda pulp was cytotoxic, apparently due to a larger content of silica particles. All the CNF materials were 3D printable. We conclude that the noncytotoxic CNF pro...

Fil: Dagnino, Eliana Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico (Nordeste). Instituto de Modelado e Innovación Tecnológica. Centro de Investigación en Química Orgánica Biológica; Argentina. Fil: Dagnino, Eliana Paola. Universidad Nacional del Nordeste. Instituto de Modelado e Innovación Tecnológica. Centro de Investigación en Química Orgánica Biológica; Argentina. Fil: Dagnino, Eliana Paola. Universidad Tecnológica Nacional. Instituto de Modelado e Innovación Tecnológica. Centro de Investigación en Química Orgánica Biológica; Argentina. Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico (Nordeste). Instituto de Materiales de Misiones. Programa de celulosa y papel; Argentina. Fil: Felissia, Fernando Esteban. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Química y Naturales. Instituto de Materiales de Misiones. Programa de celulosa y papel; Argentina. Fil: Chamorro, Ester Ramona. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico (Nordeste). Instituto de Modelado e Innovación Tecnológica. Centro de Investigación en Química Orgánica Biológica; Argentina. Fil: Chamorro, Ester Ramona. Universidad Nacional del Nordeste. Instituto de Modelado e Innovación Tecnológica. Centro de Investigación en Química Orgánica Biológica; Argentina. Fil: Chamorro, Ester Ramona. Universidad Tecnológica Nacional. Instituto de Modelado e Innovación Tecnológica. Centro de Investigación en Química Orgánica Biológica; Argentina. Fil: Area, María Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico (Nordeste). Instituto de Materiales de Misiones. Programa de celulosa y papel; Argentina. Fil: Area, María Cristina. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Química y Naturales. Instituto de Materiales de Misiones. Programa de celulosa y papel; Argentina. The delignification kinetics of lignocellulosic waste is an important tool for the study of the technical-economic viability of biorefinery processes. The aim of this work was to study the kinetic of lignin extraction by a soda-ethanol treatment of hemicelluloses-free rice husk, within the framework of a biorefinery. Additionally, the type of phenolic structures in the extracted lignin and the behavior of inorganics were evaluated. The kinetic study was carried out at 140, 150, and 160 °C, at different times between 3 and 100 min of reaction for each temperature. A first order kinetic model was adjusted to the experimental data of residual lignin in the treated solid in the fast and slow phase. The kinetic constant k0 varied from 0.021 to 0.035min-1 for 140 to 160 °C. The activation energies were 38.59 KJ/mol and 33.47KJ/mol for the fast and slow phase, respectively. The inorganics components remained in the solid and the proportion of silicon increased through all treatments. About 50% of the initial lignin with 1% of inorganics was recovered by precipitation. The percentage of total OH in lignin remained high, about 8.5%, and decreased with the temperature but not with the time of the reaction.

Fil: Dagnino, Eliana Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet (Nordeste). Instituto de Modelado e Innovación Tecnológica. Centro de Investigación en Química Orgánica Biológica; Argentina. Fil: Dagnino, Eliana Paola. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas, Naturales y Agrimensura. Instituto de Modelado e Innovación Tecnológica. Centro de Investigación en Química Orgánica Biológica; Argentina. Fil: Dagnino, Eliana Paola. Universidad Tecnológica Nacional. Instituto de Modelado e Innovación Tecnológica. Centro de Investigación en Química Orgánica Biológica; Argentina. Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico (Nordeste). Instituto de Materiales de Misiones. Programa de Pulpa y Papel; Argentina. Fil: Felissia, Fernando Esteban. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales. Instituto de Materiales de Misiones. Programa de Pulpa y Papel; Argentina. Fil: Chamorro, Ester Ramona. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet (Nordeste). Instituto de Modelado e Innovación Tecnológica. Centro de Investigación en Química Orgánica Biológica; Argentina. Fil: Chamorro, Ester Ramona. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas, Naturales y Agrimensura. Instituto de Modelado e Innovación Tecnológica. Centro de Investigación en Química Orgánica Biológica; Argentina. Fil: Chamorro, Ester Ramona. Universidad Tecnológica Nacional. Instituto de Modelado e Innovación Tecnológica. Centro de Investigación en Química Orgánica Biológica; Argentina. Fil: Area, María Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico (Nordeste). Instituto de Materiales de Misiones. Programa de Pulpa y Papel; Argentina. Fil: Area, María Cristina. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales. Instituto de Materiales de Misiones. Programa de Pulpa y Papel; Argentina. The aim of this work was to optimize the delignification of the hemicelluloses-free fraction of rice husk to obtain fractions of lignin, cellulose, and inorganics, which could be valorized in the context of the rice husk biorefinery. The hemicelluloses were pre-extracted from the raw material by dilute sulfuric acid, and a soda-ethanol-water process was used for delignification. Two experimental designs were carried out to evaluate different ranges of the same variables (strong and light conditions), aiming to promote maximal delignification or delignify while protecting carbohydrates. The optimal delignification points were obtained using 13 and 8% of NaOH (%w/w on solid material), in a 50:50 and 54:46 ethanol:water solution. In these conditions, 94.3 and 90.1% of lignin and almost 100 and 40% of inorganics were removed from the solid, respectively. The used soda-ethanol-water process can be defined as a soda process additivated with ethanol, showing significant advantages over soda-anthraquinone process for the fractionation of lignocellulosic materials.

This work aimed to study the influence of the initial chemical composition (glucans, lignin, xylan, and mannans), intrinsic viscosity, and carboxylate groups of pulps on the production process and final properties of lignocellulosic nanofibers (LCNF). Pulps of pine sawdust, eucalyptus sawdust, and sugarcane bagasse subjected to conventional pulping and highly oxidized processes were the starting materials. The LCNF were obtained by TEMPO mediated oxidation and mechanical fibrillation with a colloidal grinder. The nanofibrillation degree, chemical charge content, rheology, laser profilometry, cristallinity and atomic force microscopy were used to characterize the LCNF. The carboxylate groups, hemicelluloses and lignin of the initial pulps were important factors that affected the production process of LCNF. The results revealed that intrinsic viscosity and carboxylate groups of the initial pulps affected LCNF production process, whereas lignin and hemicelluloses influenced the viscosity of LCNF aqueous suspensions, the roughness of LCNF films, and the carboxylate groups content of LCNF. Fil: Ehman, Nanci Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Lourenço, Ana Filipa. Universidad de Coimbra; Portugal Fil: McDonagh, Birgitte Hjelmeland. Rise, Paper And Fibre Research; Noruega Fil: Vallejos, María Evangelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Ferreira, Paulo Jorge Tavares. Universidad de Coimbra; Portugal Fil: Chinga Carrasco, Gary. Rise, Paper And Fibre Research; Noruega Fil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina

A profitability requirement for biorefineries is the integral use of raw materials through efficient and optimized fractionation processes. Supercritical carbon dioxide has been stated as a promising green solvent which advantages have been previously suggested in the literature. This work evaluates the effect of subcritical and supercritical CO2 in both the hydrothermal treatment and the organosolv delignification, either as individual stages or as sequential processes, using pine sawdust, chips, and milled chips as raw materials. Both, the hydrothermal and the organosolv trials were first performed according to simple factorial designs, followed by a set of extra experiments for further understanding of the pine behavior. Carbohydrates content in the hydrothermal liquors and structural carbohydrates and lignin in the final pulps were analyzed. The yield (percentage of final biomass over original biomass) of the hydrothermal trials ranged from 76.2%–99.2%. CO2 effect on yield and hemicelluloses removal is more noticeable at shorter periods and low (120 °C) and mild temperatures (160 °C), and it weakens as reaction time and temperature increase. The delignification rate during organosolv pulping ranged between 10.3 % and 70.1 %. For industrial sawdust, the presence of CO2 during organosolv pulping significantly decreased delignification. The effect of hemicelluloses removal before organosolv pulping varies depending on the raw material, but in general, has a deleterious effect on delignification of pulps. Fil: Imlauer Vedoya, Camila María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Vallejos, María Evangelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Raffaeli, Natalia. Universidad Nacional de La Plata; Argentina Fil: da Silva Curvelo, Antonio Aprigio. Universidade de Sao Paulo; Brasil

Cellulose nanofibril (CNF) films were prepared from side streams generated by the sugarcane industry, that is, bagasse. Two fractionation processes were utilized for comparison purposes: (1) soda and (2) hot water and soda pretreatments. 2,2,6,6-Tetramethylpiperidinyl-1-oxyl-mediated oxidation was applied to facilitate the nanofibrillation of the bagasse fibers. Poly(ethylene glycol) (PEG) was chosen as plasticizer to improve the ductility of CNF films. The neat CNF and biocomposite films (CNF and 40% PEG) were used for fabrication of self-standing humidity sensors. CNF-based humidity sensors exhibited high change of impedance, within four orders of magnitude, in response to relative humidity (RH) from 20 to 90%. The use of plasticizer had an impact on sensor kinetics. While the biocomposite film sensors showed slightly longer response time, the recovery time of these plasticized sensors was two times shorter in comparison to sensors without PEG. This study demonstrated that agroindustrial side streams can form the basis for high-end applications such as humidity sensors, with potential for, for example, packaging and wound dressing applications. Fil: Syrový, Tomáš. University Of Pardubice; República Checa Fil: Maronová, Stanislava. University Of Pardubice; República Checa Fil: Kuberský, Petr. University Of West Bohemia; República Checa Fil: Ehman, Nanci Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Vallejos, María Evangelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Pretl, Silvan. University Of West Bohemia; República Checa Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Chinga Carrasco, Gary. RISE PFI; Noruega

Sugarcane bagasse, an abundant residue, is usually burned as an energy source. However, provided that appropriate and sustainable pulping and fractionation processes are applied, bagasse can be utilized as a main source of cellulose nanofibrils (CNF). We explored in this study the production of CNF inks for 3D printing by direct-ink-writing technology. The CNF were tested against L929 fibroblasts cell line and we confirmed that the CNF from soda bagasse fibers were found not to have a cytotoxic potential. Additionally, we demonstrated that the alginate and Ca 2+ caused significant dimensional changes to the 3D printed constructs. The CNF-alginate grids exhibited a lateral expansion after printing and then shrank due to the cross-linking with the Ca 2+ . The release of Ca 2+ from the CNF and CNF-alginate constructs was quantified thus providing more insight about the CNF as carrier for Ca 2+ . This, combined with 3D printing, offers potential for personalized wound dressing devices, i.e. tailor-made constructs that can be adapted to a specific shape, depending on the characteristics of the wound healing treatment. Fil: Chinga Carrasco, Gary. Research Institutes of Sweden. Paper and Fibre Research Institute; Suecia Fil: Ehman, Nanci Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Filgueira, Daniel. Research Institutes of Sweden. Paper and Fibre Research Institute; Suecia Fil: Johansson, Jenny. Research Institutes of Sweden. Bioscience and Materials; Suecia Fil: Vallejos, María Evangelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Håkansson, Joakim. Research Institutes of Sweden. Bioscience and Materials; Suecia Fil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina

Soda-ethanol pulps, prepared from a forestry residue pine sawdust, were treated according to high-consistency enzymatic fibrillation technology to manufacture nanocellulose. The obtained nanocellulose was characterized and used as ink for three-dimensional (3D) printing of various structures. It was also tested for its moisture sorption capacity and cytotoxicity, as preliminary tests for evaluating its suitability for wound dressing and similar applications. During the high-consistency enzymatic treatment it was found that only the treatment of the O2-delignified pine pulp resulted in fibrillation into nano-scale. For 3D printing trials, the material needed to be fluidized further. By 3D printing, it was possible to fabricate various structures from the high-consistency enzymatic nanocellulose. However, the water sorption capacity of the structures was lower than previously seen with porous nanocellulose structures, indicating that further optimization of the material is needed. The material was found not to be cytotoxic, thus showing potential as material, e.g., for wound dressings and for printing tissue models. Fil: Kangas, Heli. Technical Research Centre; Finlandia Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Filgueira, Daniel. No especifíca; Fil: Ehman, Nanci Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Vallejos, María Evangelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Imlauer Vedoya, Camila María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Lahtinen, Panu. Technical Research Centre; Finlandia Fil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Chinga Carrasco, Gary. No especifíca

This work investigates the valorization of sodium lignosulfonate, kraft, and organosolv lignins from South America. A detailed characterization of the lignins and their chemical modification by hydroxymethylation through its reaction with formaldehyde were performed. The characterization included measurements of moisture, ash, carbohydrate contents, elemental and thermogravimetric analysis, and functional groups, molar mass distributions by Fourier transform infrared spectroscopy, and size exclusion chromatography, respectively. Also, reactive aromatic hydrogens ( HAr) were quantified by the measurement of phenolic hydroxyl groups (P-OH) content by UV–Vis spectroscopy. The different initial formaldehyde/lignin weight ratios (0.07, 1.47), temperatures (40, 50, and 70 C), and pHs (9, 11); and the following of hydroxymethylation reactions by UV–Vis spectroscopy were investigated. All lignins resulted attractive for the use as replacement of phenol in phenolic resins, but sodium lignosulfonate was the most appropriate due to its water solubility. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47712. Fil: Taverna, María Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina. Universidad Tecnológica Nacional; Argentina Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Estenoz, Diana Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina Fil: Nicolau, Verónica Viviana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Tecnológica Nacional; Argentina

Sustainable biomass valorization, as agricultural and forestry wastes, and the development of conversion processes could bring additional benefits like solving the residue disposal, generating renewable biofuels and bio-based chemicals, reducing net greenhouse gas emissions, and creating more manufacturing jobs, among others. The commercialized processes based on the biorefinery concept are increasing in chemicals and biofuels production, which can be integrated into the conventional manufacturing processes. These processes generated dilute aqueous streams with numerous side products and waste streams. The biorefinery schemes on an industrial scale require the process design and technical and economic assessment to establish its viability and to elucidate its potential socioeconomic effect at local and regional levels. The reviewed literature shows the obtaining of several marketable industrial interest products with high yields of the final product. The most significant variables and parameters should be established and enhanced to attain efficient and profitable processes. The diverse schemes of biorefinery can be assessed based on the process design, the mass, and energy integration, economic assessment, and risk and sensibility analysis. This work presents a framework for the design, analysis, and assessment of biorefinery schemes. They could be integrated into agricultural and forestry waste production chains for their valorization. Sections 1–5 define the steps to follow for the design, analysis, and assessment of biorefinery schemes. A case study to demonstrate the application of the proposed scheme is shown in Section 6. Finally, in Section 7, some challenges in the design and analysis of a multi-product biorefinery are presented.

The aim of this study was to evaluate strategies of detoxification and fermentation of the hemicellulosic liquors obtained from sugarcane bagasse autohydrolysis, for the biotechnological production of xylitol. Different sequences of detoxification treatments were performed, and their effects on sugars loss and inhibitors removal were evaluated. Fermentation assays were accomplished with commercial xylose to selectthe best yeast(C. guilliermondii, C.tropicalis) and the fermentation conditions ofthe detoxified spent liquors. Detoxification through a sequence oftreatments, including Ca(OH)2, IR-120 resin, activated charcoal, and IRA-67 resin, practically removed all inhibitors from the hemicellulosic spent liquors. Maximal concentration of xylitol obtained was 32.0 g L−1 (C. tropicalis, xylose: 104.1 g L−1, yield: 0.46 g g−1, productivity: 0.27 g L−1 h−1). The technological parameters to obtain a detoxified spent liquor rich in xylose and its bioconversion to xylitol were determined Fil: Vallejos, María Evangelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Chade, Miriam Estela. Universidad Nacional de Misiones. Facultad de Cs.exactas Químicas y Naturales. Departamento de Medio Ambiente; Argentina Fil: Mereless, Elizabeth Beda. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales; Argentina Fil: Bengoechea, Dora Inés. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales; Argentina Fil: Brizuela, Johanna Gisela. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales; Argentina Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina

Hemicellulose hydrolysates (HH), which could be an interesting carbon source to feed mixed microbial cultures (MMC) able to accumulate high value-added compounds. This research focused on the evaluation of a culture strategy to achieve the simultaneous biological production of Levulinic Acid (LA) and Polyhydroxyalcanoates (PHA) by MMC fed with a synthetic HH (SHH). The culture strategy involves the use of sequential batch reactors (SBR) to select microorganisms capable of producing LA and PHA. This work proved that the cultivation strategy used allowed the biological production of LA, reaching 37%w/w when the SHH was composed of 85% pentoses. In addition, the simultaneous biological production of LA and PHB was possible when the SHH was enriched with acetate (45% pentoses - 50% acetate). Finally, this study showed that the composition of the SHH impacts directly on the selected microorganism genus and the type and quantity of the value-added compounds obtained. Fil: Pinto Ibieta, Fernanda. Universidad de La Frontera; Chile. Universidad Catolica de Temuco; Chile Fil: Cea, Mara. Universidad de la Frontera. Facultad de Ingeniería y Ciencias; Chile Fil: Cabrera, Francisco. Universidad Autónoma de Chile; Chile Fil: Abanto, Michel. Universidad de La Frontera; Chile Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Ciudad, Gustavo. Universidad de La Frontera; Chile

Sugarcane bagasse is a lignocellulosic agro-industrial waste, which is usually burned in the sugar and bio-ethanol mills to produce heat and electricity. This work presents the kinetic study of the carbohydrates extracted from the mild hot water pretreatment of sugarcane bagasse, to explain the variation of hemicellulosic carbohydrates during the treatment. This could allow the selection of optimum conditions to obtain the desired products in spent liquors, as high concentration of xylans and low concentrations of fermentation inhibitors. Sugarcane bagasse was hydrothermally treated under isothermal conditions at 160, 170, and 180 ◦C, using a liquid to solid ratio of 14:1. Glucans, xylans, arabans, xylose, glucose, arabinose, acetic acid, formic acid, HMF and furfural were first identified in the spent liquor. A kinetic model was applied, considering the direct extraction of xylose and oligomers from the solid, xylose production from the oligomers, and furfural generation from xylose. It was supposed that the reaction rate constants have first-order kinetics. The fractionation by hydrothermal treatment has proven to be effective for hemicelluloses removal. Most glucans were retained in the solid, and a partial delignification (at 180 ◦C, 9.8% and 36.3% of the initial lignin at 20 and 240 min, respectively) was achieved. The maximum concentration of xylans in spent liquors with the low furfural content (0.5% on oven dry bagasse) was achieved at 180 ◦C and 20 min of treatment (17.6% on oven dry bagasse, about 74% of the initial amount). An activation energy of 128.8 kJ mol−1 has been obtained for the fast hydrolysis of xylans from sugar cane bagasse. The maximal concentration of xylans + xylose in liquors was obtained with a P-factor of 800. Fil: Vallejos, María Evangelina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnológico Nordeste. Instituto de Materiales de Misiones; Argentina. Universidad Nacional de Misiones; Argentina Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnológico Nordeste. Instituto de Materiales de Misiones; Argentina. Universidad Nacional de Misiones; Argentina Fil: Kruyeniski, Julia. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnológico Nordeste. Instituto de Materiales de Misiones; Argentina. Universidad Nacional de Misiones; Argentina Fil: Area, Maria Cristina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnológico Nordeste. Instituto de Materiales de Misiones; Argentina. Universidad Nacional de Misiones; Argentina

Fil: Stoffel, Romina Bettiana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico (Nordeste). Instituto de Materiales de Misiones. Programa de Pulpa y Papel; Argentina. Fil: Stoffel, Romina Bettiana. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales. Instituto de Materiales de Misiones. Programa de Pulpa y Papel; Argentina. Fil: Neves, Priscila Vinholi. Universidad Federal de Paraná. Departamento de Química. Centro de Investigación en Química Aplicada; Brasil. Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico (Nordeste). Instituto de Materiales de Misiones. Programa de Pulpa y Papel; Argentina. Fil: Felissia, Fernando Esteban. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales. Instituto de Materiales de Misiones. Programa de Pulpa y Papel; Argentina. Fil: Ramos, Luiz Pereira. Universidad Federal de Paraná. Departamento de Química. Centro de Investigación en Química Aplicada; Brasil. Fil: Gassa, Liliana Mabel. Universidad Nacional de La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; Argentina. Fil: Gassa, Liliana Mabel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fil: Area, María Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico (Nordeste). Instituto de Materiales de Misiones. Programa de Pulpa y Papel; Argentina. Fil: Area, María Cristina. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales. Instituto de Materiales de Misiones. Programa de Pulpa y Papel; Argentina. One of the main obstacles to the development of advanced forest biorefineries is the optimal fractionation of the plant biomass. The aim of this work was to design a two-stage process for the fractionation of slash pine sawdust: alkaline deresination for extractives removal and sulfuric acid-catalyzed steam explosion (SE) for hemicellulose extraction. SE was carried out in a high-pressure steam reactor under different conditions of temperature (180 °C–200 °C), time (5 min–10 min) and acid concentration (1:100 H2SO4 - 3:100 H2SO4 (on mass of dry wood)) according to a factorial design. Extractives, lignin, carbohydrates, and degradation by-products were quantified. The effect of pretreatment on enzymatic hydrolysis (EH) was also evaluated. SE was very efficient for hemicelluloses extraction (90% at 200 °C with 3:100 H2SO4 (on mass of dry wood) for 5 min) with a high glucan recovery. EH yield increased 6-fold after SE. There was a trade-off between maximizing carbohydrate recovery, hemicellulose extraction, and cellulose digestibility.

Fil: Clauser, Nicolás Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico (Nordeste). Instituto de Materiales de Misiones; Argentina. Fil: Clauser, Nicolás Martín. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Química y Naturales. Instituto de Materiales de Misiones; Argentina. Fil: Gutiérrez, Leticia Soledad. Universidad de la República. Facultad de Ingeniería; Uruguay. Fil: Area, María Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico (Nordeste). Instituto de Materiales de Misiones; Argentina. Fil: Area, María Cristina. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Química y Naturales. Instituto de Materiales de Misiones; Argentina. Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico (Nordeste). Instituto de Materiales de Misiones; Argentina. Fil: Felissia, Fernando Esteban. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Química y Naturales. Instituto de Materiales de Misiones; Argentina. Fil: Vallejos, María Evangelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico (Nordeste). Instituto de Materiales de Misiones; Argentina. Fil: Vallejos, María Evangelina. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Química y Naturales. Instituto de Materiales de Misiones; Argentina. Small-scale biorefinery from sugarcane bagasse offers new possibilities to the sugar and ethanol industries. The aim of this study was to evaluate the feasibility of a small-scale biorefinery for the production of xylitol from sugarcane bagasse. The liquid fraction from the autohydrolysis treatment was selected as the source of sugars for xylitol and two scenarios were analyzed for the residual solid: ethanol or pellet production. A technical-economic analysis of alternatives was applied. The internal rate of return (IRR) was used to compare the selected proposals. The highest IRR values were obtained when processing 70,000 dry tons per year of bagasse. The results showed promising prospects for a small-scale biorefinery with capacities above 20,000 dry tons per year (xylitol and pellets), and above 50,000 dry tons per year (xylitol and ethanol).

The aim of this study was to evaluate the effects of dose and dose rate of gamma irradiation on the physical properties of commercial papers commonly used in libraries and archives to optimize the irradiation conditions. Three different brands of paper of different fiber compositions were treated, using a 32 factorial design with four replicates of the center point, with doses ranging from 2 to 11 kGy and dose rates between 1 and 11 kGy/h. Chemical, mechanical and optical properties were determined on the samples. With some differences between the different kinds of papers, tensile strength, elongation, TEA, and air resistance were in general, unaffected by the treatment. The minimum loss of tear resistance and brightness were obtained with doses in the range 4–6 kGy at any dose rate for all three kinds of paper. These conditions are ideal to remove insects and sufficient to eliminate fungus. Fil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Cs.exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Calvo, Ana María. Comisión Nacional de Energía Atómica; Argentina Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Cs.exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Docters, Andrea. Comisión Nacional de Energía Atómica; Argentina Fil: Miranda, María V.. Comisión Nacional de Energía Atómica; Argentina

The structural complexity of the lignocellulosic materials hinders enzymatic hydrolysis for what their conversion to bioethanol requires a pretreatment step. The aim of this work was to optimize the pretreatment of rice hulls with diluted acid. A Central Composite Design (CCD) was used to obtain regression equations in function of the variables: acid concentration and heating time. Optimal conditions were obtained by the Desirability function. As a strategy to obtain the best solid material for the production of ethanol by fermentation minimizing sugars degradation, the optimization of the pretreatments was performed following three scenarios. The optimum was established as the conditions that maximize glucans in the solid and xylose in the liquid (0.3%w/V of sulfuric acid and a 33min). The pretreated rice hull in those conditions was treated enzimatically. The performance of the enzymatic hydrolysis of was about 50% (25% of total sugars present) over a period of 48 h of reaction, and the efficiency of conversion of dissolved sugars to bioethanol was of 84%. Fil: Dagnino, Eliana Paola. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Ingeniería Mecánica; Argentina. Universidad Tecnologica Nacional; Argentina Fil: Chamorro, E. R.. Universidad Tecnológica Nacional. Facultad Regional Resistencia. Centro de Investigación En Química Orgánica Biológica; Argentina Fil: Romano, Silvia Daniela. Universidad de Buenos Aires. Facultad de Ingeniería; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Felissia, F. E.. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales; Argentina Fil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales; Argentina

Small-sized biorefineries are not capital intensive and have lower transportation cost, lesser movements of liquid and solid streams, and lower heat transfer problems than high-sized ones. In this work, different scenarios were investigated in order to determine technical and economic viability of different processes to produce valuable products from sugarcane bagasse by small-sized biorefineries. Different alternatives were evaluated, as furfural and xylitol production from hemicelluloses, as well as energy generation and medium-density fibreboard (MDF) production from the residual solid after hemicelluloses hydrolysis. Experimental data obtained by the authors in previous works were used for pretreatment steps, and updated literature data was used for the other processes. A simplified kinetic model was developed for the extraction of xylose, and unit operations processes were selected and simulated. The most profitable option was determined for hemicelluloses use. In addition, costs and benefits that could be obtained exploiting the residual solid feedstock were estimated. The economic evaluation shows that recovery periods are extensive in both scenarios. However, optimization of different steps as liquid to solid ratio of pretreatment, evaporation, or fermentation, could represent attractive and innovative alternatives in order to reduce the recovery periods of capital costs. Fil: Clauser, Nicolás Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Gutiérrez, Soledad. Universidad de la República; Uruguay Fil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Vallejos, María Evangelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina

The influence of different addition points of a chelating agent and a counter-ion exchange on the properties of Eucalyptus grandis unbleached kraft pulps is studied. Seven pulps were considered: two laboratory kraft pulps with or without the inclusion of the chelant DTPMPA (diethylene triamine penta (methylene phosphonic acid)), a mill kraft pulp and four mill pulps after Ca +2 or Na + counter-ion exchange followed, or not, by washing with DTPMPA addition. The laboratory pulps required lower beating energy than the industrial pulps for achieving 30°SR, and the corresponding handsheets also showed better strength and optical properties, as well as a more homogeneous and smooth surface. The counter-ion exchange decreases the mechanical resistances and increases brightness. However, the effects of Ca +2 are deeper than those of Na + . DTPMPA added to pulping causes a decrease in calcium content whereas as a washing additive does not have a relevant impact on the mechanical and optical properties.

Scale formation in the digester during kraft pulping represents a great problem in pulp mills. Scaling reduces pulping control and efficiency, increasing energy costs and leading to cleaning breakdowns, with subsequent losses in productivity. The kraft process promotes CaCO3 scaling due to high calcium ion and carbonate concentrations, as well as high alkalinity and temperature levels, which increase the speed with which liquors reach a state of supersaturation. This work examines the action of diethylene triamine penta(methylene phosphonic acid) (DTPMPA), either alone or combined with commercial anti-scaling agents, as an inhibitor of calcium carbonate precipitation in the kraft pulping of Pinus taeda. The theoretical amount of calcium deposited in the digester was obtained by mass balance. Soluble calcium was stable throughout cooking when using the phosphonates alone or combined with anti-scaling agents. When adding only DTPMPA, calcium stays in the pulp, rather than forming deposits.

This chapter discusses the fouling that occurs in evaporators used to concentrate the black liquor in kraft pulp mills. Initially, the chemical nature of black liquors and the location of the recovery process within the framework of the kraft mill are briefly described. It includes an explanation about the different types of fouling and how they evolved over time due to changes that were made in the pulping process and due to evaporation technologies. It also describes the nature of the deposits and various proposals for mitigation. Finally, a series of case studies is presented. Fil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina

Fil: Covinich, Laura Gabriela. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Quimicas y Naturales. Instituto de Materiales de Misiones; Argentina

The aim of this work was to apply an alkaline–acid sequence for the fractionation of slash pine sawdust, to obtain a solid lignocellulosic material (which can be subsequently delignified to obtain pure cellulose), and separate liquid fractions containing extractives and hemicelluloses. Processes were optimized using a central composite design of two variables for the alkaline extraction stage (NaOH concentration and temperature), and another of three variables for the acid treatment (H2SO4 concentration, time and temperature). Yield and contents of extractives, lignin, carbohydrates and degradation products, all by NREL Standards were determined. Maximum removal of extractives in the alkaline stage (90.7%) was reached using 5% NaOH (oven dry basis, od) at 90 °C for 1 h, and maximum hemicelluloses extraction in the acid stage (57%) was obtained using 7.5 g/L H2SO4 at 150 °C for 30 min The alkaline–acid sequence has shown to be effective for the sequential extraction of resin and hemicelluloses from slash pine sawdust, making possible its use for the production of high value products. Fil: Stoffel, Romina Bettiana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Cs.exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Cs.exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Curvelo da Silva, Antonio Aprigio. Universidade de Sao Paulo; Brasil Fil: Gassa, Liliana Mabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; Argentina Fil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Cs.exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina

Weed control and fertilization usually lead to an increase in the growth rate of trees and, consequently, to a possible modification of the quality of the wood and its end products. The effect of weed control and fertilization practices were determined on tree growth parameters, wood density, fiber weight, fiber length, and chemical wood composition, as well as the chemi-mechanical pulp properties, for 8-year-old Populus deltoides `Delta Gold´ grown in Argentina. Four treatments belonging to a randomized complete block design trial were analysed: no weeding after planting (C), mechanical weed control (M), chemimechanical weed control (CHM), and fertilized + chemimechanical weed control (CHM-F). Soda-sulfite chemi-mechanical pulps were produced from said trees. Handsheets were prepared from the pulps, and their physical, mechanical, and optical properties were determined following international standards. Several wood and pulp properties were influenced by the studied silvicultural practices. In the context of this study, silvicultural treatments applied to Populus deltoides ‘Delta Gold’ (formerly ‘Stoneville 66’) trees can be applied to increase productivity (volume and fibrous output) without detrimental consequences to wood and pulp properties, except for a slight reduction in brightness., Facultad de Ciencias Agrarias y Forestales

Forest plantations of Salicaceae (poplars and willows) in Argentina are mainly used for the manufacture of pulp for newsprint. The rapid growth of these species results in a decrease in rotation age, which increases the proportion of juvenile wood. The aim of this work was to define the proportions of juvenile wood (JW) and mature wood (MW) of these species that can optimize the mechanical and optical properties of chemimechanical pulps for newsprint production. A two-component mixture type experimental design was used with proportions (JW:MW) of 0:100%, 25:75%, 50:50%, 75:25%, and 100:0%. When the mechanical properties were optimized, the highest desirability function was obtained with a JW:MW ratio of 100:0%, and the optimal ratio for optical properties was 0:100%. The pattern of variation of mechanical properties can be attributed to the higher density of MW, whilst that of the optical properties can be attributed to the higher content of extractives in the JW., Facultad de Ciencias Agrarias y Forestales

The black carob tree (Prosopis nigra) is a particularly valued species in Chaco, Argentina on account of its hard wood. Finding a use for the sawdust, the main industrial residue of wood, could be useful within the furniture industry of any country in the tropics seeking to apply the biorefinery concept. For the conversion of wood carbohydrates to bioethanol, a pretreatment stage is necessary. The objective of this work was to find the acid pretreatment conditions that maximize the extraction of xylose with minimum degradation, while maximizing the concentration of glucans in the pretreated solid to obtain better enzymatic accessibility, using black carob tree sawdust as the raw material. The optimization was carried out by use of a central composite design (CCD) with two independent variables: the concentration of the sulfuric acid solution and the heating time. Optimal enzymatic hydrolysis occurred at the mean values of the tested acid solution concentration (1.2%) and after shorter heating times (10.2 min). The concentration of sugars after the enzymatic hydrolysis of the pretreated solid over a time period of 72 h was three times higher than the untreated solid. Fil: Dagnino, Eliana Paola. Universidad Tecnológica Nacional. Facultad Regional Resistencia. Centro de Investigación en Química Orgánica Biológica; Argentina; Fil: Chamorro, Ester Ramona. Universidad Tecnológica Nacional. Facultad Regional Resistencia. Centro de Investigación en Química Orgánica Biológica; Argentina; Fil: Romano, Silvia Daniela. Universidad de Buenos Aires. Facultad de Ingeniería. Grupo de Energías Renovables; Argentina; Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales. Programa de Celulosa y Papel; Argentina; Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Ingeniería Mecánica; Argentina; Fil: Felissia, Fernando Esteban. Universidad Nacional de Misiones; Argentina; Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales. Programa de Celulosa y Papel; Argentina; Fil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina; Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales. Programa de Celulosa y Papel; Argentina