The Experts below are selected from a list of 7959 Experts worldwide ranked by ideXlab platform
Maija Tenkanen - One of the best experts on this subject based on the ideXlab platform.
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environmentally compatible alkyd paints stabilized by wood hemicelluloses
Industrial Crops and Products, 2019Co-Authors: Kirsi S Mikkonen, Andrey Pranovich, Satu Kirjoranta, Chunlin Xu, Ndegwa Henry Maina, Mamata Bhattarai, Petri Kilpelainen, Jarl Hemming, Leena Peltonen, Maija TenkanenAbstract:Abstract Wood Biorefining currently involves large-scale industrial processes where a notable portion of raw materials, namely hemicelluloses and lignin, are either lost with the process water, degraded, or burnt for energy. Value-added utilization of polymeric hemicelluloses is challenging due to their intermediate molar mass and the presence of other wood components, such as phenolic residues or wood extractives. Oil-in-water (O/W) emulsions represent a diverse and abundant class of applications in which the natural properties of wood hemicelluloses are beneficial. In the current work, we present highly promising new technical alkyd paint emulsion systems stabilized with hardwood glucuronoxylans (GX) and softwood galactoglucomannans (GGM). Samples from three isolation methods and their further fractionation by ethanol precipitation were systematically compared with regard to hemicellulose composition, interfacial activity, and functionality in emulsions. Emulsification of alkyd resins was successful with both GX and GGM obtained by various Biorefining strategies. The highest emulsion stability over storage was achieved using crude non-purified GX and GGM fractions, and was correlated with the presence of phenolic compounds and extractives, interfacial activity, and small droplet size. Hardwood GX and softwood GGM are envisioned as natural emulsifiers of alkyd O/W emulsions, which are examples of diverse and abundantly-used technical dispersions. This study can be utilized as a guideline for targeted extraction of hemicelluloses with desired functionality, and as a protocol for developing environmentally-compatible industrial dispersions.
E. L. Akim - One of the best experts on this subject based on the ideXlab platform.
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Change in Relaxation State of Polymer Components of Wood During its High-Temperature Biorefining
Fibre Chemistry, 2019Co-Authors: E. L. Akim, Yu. G. Mandre, A. A. PekaretsAbstract:The change in relaxation state of polymer components of wood during its high-temperature Biorefining and extrusion briquetting and subsequent heating at 380-450°C, i.e., above the thermal decomposition temperature of wood, is analyzed. It is demonstrated that the system can be translated into brittle state by changing the moisture content of the wood and treatment temperature and into forced plastic state by subsequent moistening, heating, and compression-shearing. Carbonization and activation of charcoal briquettes can be combined by subsequent low-temperature pyrolysis in controlled vaporgas environment conditions.
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Biorefining of Wood
Fibre Chemistry, 2016Co-Authors: E. L. AkimAbstract:This article gives a brief review of our research over the 10 years that have passed since the Rogovin Lectures devoted to the 100th birthday of Z. A. Rogovin [ 1 ].
Michael O'donohue - One of the best experts on this subject based on the ideXlab platform.
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Progress and future prospects for pentose-specific biocatalysts in Biorefining
Process Biochemistry, 2012Co-Authors: Claire Dumon, Letian Song, Sophie Bozonnet, Régis Fauré, Michael O'donohueAbstract:Due to the fact that cellulose represents up to 60% of the dry weight of plant-derived biomass, so far R&D efforts have mainly focused on the extraction and conversion of cellulose into added value products. Consequently, abundant heteroxylans have been somewhat neglected in current biomass-to-fuel concepts. The "glucocentric" approach to Biorefining means that extraction technologies are sub-optimal and non-specific with regard to pentose sugars, the development of hemicellulases as Biorefining enzymes has been slow and pentose-specific conversion technologies for the production of value-added products are relatively scarce. Nevertheless, xylan-related biocatalysis has continued to make steady progress in many areas, including the discovery and characterization of a wide range of hemicellulases, which are important enzymes for biomass hydrolysis. Similarly, the development of high-performance ethanol producing yeast has focused for many years on the recruitment of pentose isomerases or, alternatively, pentose reductases and pentitol dehydrogenases. However, similar efforts are being made to develop microorganisms for alternative bioconversion processes that are widening the range of chemicals that can be derived from pentoses. Finally, progress is also being made in the area of glycosynthesis, which is opening new prospects for the use of pentose sugars as building blocks for engineered pentosides, which will have quite different applications, such as non-ionic surfactants or prebiotic food/feed ingredients. This review provides an overview of these different development areas and discusses future prospects for discovery and impact on Biorefining. (C) 2011 Elsevier Ltd. All rights reserved.
Anthony Turhollow - One of the best experts on this subject based on the ideXlab platform.
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Corn stover availability for biomass conversion: situation analysis
Cellulose, 2009Co-Authors: J. Richard Hess, Kevin L. Kenney, Christopher T. Wright, Robert Perlack, Anthony TurhollowAbstract:As Biorefining conversion technologies become commercial, feedstock availability, supply system logistics, and biomass material attributes are emerging as major barriers to the availability of corn stover for Biorefining. While systems do exist to supply corn stover as feedstock to Biorefining facilities, stover material attributes affecting physical deconstruction, such as densification and post-harvest material stability, challenge the cost-effectiveness of present-day feedstock logistics systems. In addition, the material characteristics of corn stover create barriers with any supply system design in terms of equipment capacity/efficiency, dry matter loss, and capital use efficiency. However, analysis of a conventional large square bale corn stover feedstock supply system concludes that (1) where other agronomic factors are not limiting, corn stover can be accessed and supplied to a biorefinery using existing bale-based technologies, (2) technologies and new supply system designs are necessary to overcome biomass bulk density and moisture material property challenges, and (3) major opportunities to improve conventional bale biomass feedstock supply systems include improvements in equipment efficiency and capacity and reducing biomass losses in harvesting, collection, and storage. Finally, the backbone of an effective stover supply system design is the optimization of intended and minimization of unintended material property changes as the corn stover passes through the individual supply system processes from the field to the biorefinery conversion processes.
Kirsi S Mikkonen - One of the best experts on this subject based on the ideXlab platform.
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environmentally compatible alkyd paints stabilized by wood hemicelluloses
Industrial Crops and Products, 2019Co-Authors: Kirsi S Mikkonen, Andrey Pranovich, Satu Kirjoranta, Chunlin Xu, Ndegwa Henry Maina, Mamata Bhattarai, Petri Kilpelainen, Jarl Hemming, Leena Peltonen, Maija TenkanenAbstract:Abstract Wood Biorefining currently involves large-scale industrial processes where a notable portion of raw materials, namely hemicelluloses and lignin, are either lost with the process water, degraded, or burnt for energy. Value-added utilization of polymeric hemicelluloses is challenging due to their intermediate molar mass and the presence of other wood components, such as phenolic residues or wood extractives. Oil-in-water (O/W) emulsions represent a diverse and abundant class of applications in which the natural properties of wood hemicelluloses are beneficial. In the current work, we present highly promising new technical alkyd paint emulsion systems stabilized with hardwood glucuronoxylans (GX) and softwood galactoglucomannans (GGM). Samples from three isolation methods and their further fractionation by ethanol precipitation were systematically compared with regard to hemicellulose composition, interfacial activity, and functionality in emulsions. Emulsification of alkyd resins was successful with both GX and GGM obtained by various Biorefining strategies. The highest emulsion stability over storage was achieved using crude non-purified GX and GGM fractions, and was correlated with the presence of phenolic compounds and extractives, interfacial activity, and small droplet size. Hardwood GX and softwood GGM are envisioned as natural emulsifiers of alkyd O/W emulsions, which are examples of diverse and abundantly-used technical dispersions. This study can be utilized as a guideline for targeted extraction of hemicelluloses with desired functionality, and as a protocol for developing environmentally-compatible industrial dispersions.