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Wyniki wyszukiwania dla: liquefaction
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Bio‐polyols synthesized by liquefaction of cellulose: Influence of liquefaction solvent molecular weight
PublikacjaCurrently, the plastics industry including polyurethanes is based on the use of petrochemicals. For this reason, scientists are looking for new types of renewable resources for the substitution of petrochemical substances. This work aims to evaluate the effect of polyethylene glycols (PEG) with different molecular mass impact on properties of bio-based polyols synthesized via biomass liquefaction of cellulose. To date, research...
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Comparison of the Efficiency of Hetero- and Homogeneous Catalysts in Cellulose Liquefaction
PublikacjaBiomass liquefaction is a well-known and extensively described process. Hydrothermal processes are well understood and can be used in the fuel industry. The use of organic solvents can result in full-fledged products for use in the synthesis of polyurethanes. The plastics industry, including polyurethanes, is targeting new, more environmentally friendly solutions. One of these is the replacement of petrochemical polyols with compounds...
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Briefing: Liquefaction potential of oil-contaminated silty sands
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Oxygen concentration regulated the efficient liquefaction of vulcanized natural rubber
PublikacjaOxidative liquefaction represents a promising avenue for the homogeneous and high-value utilization of waste tire rubber. Given that truck tires predominantly comprise natural rubber (NR), this study investigated the efficient liquefaction of vulcanized NR regulated by oxygen concentration. Remarkably, the liquefaction of vulcanized NR was realized with an oxygen concentration of 75 % at 200 °C within 3 min. FTIR spectroscopy showed...
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Liquefaction of macroalgae Enteromorpha biomass for the preparation of biopolyols by using crude glycerol
PublikacjaThis article describes the liquefaction process of macroalgae Enteromorpha with the use of crude glycerol as a solvent and a reagent, aimed at obtaining of new bio-polyols, which are characterized with respect to their chemical structure, physical and thermal properties. Six different biopolyols were prepared. In order to optimize the liquefaction of algal biomass for the best bio-polyol properties, two catalysts (sulfuric or orthophosphoric...
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Liquefaction of alder wood as the source of renewable and sustainable polyols for preparation of polyurethane resins
PublikacjaLiquefaction of wood-based biomass gives different polyol properties depending on the reagents used. In this article, alder wood sawdust was liquefied with glycerol and poly(ethylene glycol) solvents. Liquefaction reactions were carried out at temperatures of 120, 150 and 170 °C. The obtained bio-polyols were analyzed in order to establish the process efficiency, hydroxyl number, acid value, viscosity and structural characteristics...
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Liquefaction of alder wood as the source of renewable and sustainable polyols for preparation of polyurethane resins
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Microwave assisted liquefaction with crude glycerol as a potential method of brewer's spent grain utylization
PublikacjaBrewer's spent grain was applied as a low-cost industrial type of lignocellulose biomass in a liquefaction and solvent: biomass ratio on the efficiency of the process, chemical structure and basic properties of obtained prepared polyols and soil residues shed light on the biomass degradation mechanism through application of microwaves and further reaction of degradation products with solvent particles.
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Microwave Assisted Liquefaction with Crude Glycerol as a Potential Method of Brewer’s Spent Grain Utilization
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Biopolyols obtained via crude glycerol-based liquefaction of cellulose: their structural, rheological and thermal characterization
PublikacjaIn this work lignocellulose biomass liquefaction was used to produce biopolyols suitable for the manufacturing of rigid polyurethane foams. In order to better evaluate the mechanism of the process, pure cellulose was applied as a raw material. The effect of time and temperature on the effectiveness of liquefaction and the parameters of resulting biopolyols were characterized. The prepared materials were analyzed in terms of their...
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Biopolyols obtained via microwave-assisted liquefaction of lignin: structure, rheological, physical and thermal properties
PublikacjaThe present study examined the application of polyols obtained via microwave-assisted liquefaction of lignin in the production of rigid polyurethane foam. Lignin was liquefed in crude glycerol and 1,4-butanediol at diferent temperatures (130–170 °C), without a catalyst and using various biomass concentrations (15 and 30 wt%). The physicochemical properties, process yield, and FTIR-based identifcation of the obtained polyols were...
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Synthesis and characterization of biopolyols through biomass liquefaction of wood shavings and their application in the preparation of polyurethane wood composites
PublikacjaThe sustainability of production systems in wood processing, wood industry, and wooden waste disposal is an important issue for European industry and society. Proper development of products based on renewable wood resources gives an opportunity to provide materials with long-term environmental, social, and economic sustainability. This study aims to establish a new way of forestry and agricultural waste materials utilization by...
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Chemical structures, rheological and physical properties of biopolyols prepared via solvothermal liquefaction of Enteromorpha and Zostera marina biomass
PublikacjaIn this work, liquefied biomass from the Baltic Sea was used for the preparation of rigid polyurethane (PUR) foams. The biomass contained 10 wt% of Enteromorpha macroalgae and 90 wt% of Zostera marina seagrass characterized by a high content of cellulose. The influence of time, temperature and the type of solvent on the efficiency of the liquefaction process and properties of biopolyols was determined. Obtained materials were analyzed...
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The study on application of biopolyols obtained by cellulose biomass liquefaction performed with crude glycerol for the synthesis of rigid polyurethane foams
PublikacjaIn this work rigid polyurethane foams (PUR) were obtained by replacement of 0–70 wt% of petrochemical polyol with bio-polyol obtained via cellulose liquefaction in presence of crude glycerol. The foams with different content of a bio-polyol were prepared by single step method for NCO/OH ratio equals 1.5. The prepared materials were analyzed in terms of their morphology, chemical structure, thermal stability and basic physical and...
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Characterization of Highly Filled Glass Fiber/Carbon Fiber Polyurethane Composites with the Addition of Bio-Polyol Obtained through Biomass Liquefaction
PublikacjaThis work aims to investigate the process of obtaining highly filled glass and carbon fiber composites. Composites were manufactured using previously obtained cellulose derived polyol, polymeric methylene diphenyl diisocyanate (pMDI). As a catalyst, dibutyltin dilaurate 95% and Dabco® 33-LV were used. It was found that the addition of carbon and glass fibers into the polymer matrix causes an increase in the mechanical properties...
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Valorisation of bioplastics synthesised by liquefaction of celluloseusing hetero- and homogeneous catalysts
Dane BadawczeThe purpose of the present study was to test the effectiveness of a heterogeneous catalyst such as Nafion ion-exchange resin on the cellulose liquefaction process. The results obtained were compared with the bio-polyols obtained in a conventional way, using a homogeneous catalyst (sulfuric acid (VI)). Depending on the catalyst used and the temperature...
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Valorization of bio-based polyols synthesized via biomass liquefaction
Dane BadawczeAs the properties of polyols have a huge impact on the properties of manufactured polyurethanes, this study aims to determine the influence of polyethylene glycols with different molecular masses on the course of the biomass liquefaction process and bio-polyol properties. The obtained polyols were characterized by rheological studies. To confirm the...
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Towards sustainable catalyst-free biomass-based polyurethane-wood composites (PU-WC): From valorization and liquefaction to future generation of biocomposites
PublikacjaA substantial aspect of materials engineering lies in the responsible process of designing polymer-based materials. Due to environmental pollution, excessive consumption of natural resources, and increasing environmental awareness of society, there is a massive need for polyurethane (PU) materials with reduced environmental impact. To date, research on catalyst-free polyurethane-wood composites (PU-WC) has demonstrated a huge potential...
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Bio-Based Polyurethane Networks Derived from Liquefied Sawdust
PublikacjaThe utilization of forestry waste resources in the production of polyurethane resins is a promising green alternative to the use of unsustainable resources. Liquefaction of wood-based biomass gives polyols with properties depending on the reagents used. In this article, the liquefaction of forestry wastes, including sawdust, in solvents such as glycerol and polyethylene glycol was investigated. The liquefaction process was carried...
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Bio based PUR-PIR foams thermal degradation (TG) and isoconversional kinetics
Dane BadawczeIn the present work, we perform a thorough thermogravimetric (TG) analysis of the bio-based polyurethane – polyisocyanurate (PUR-PIR) foams in both nitrogen and oxygen atmosphere. A sustainable element of the foam was a biopolyol obtained via acid-catalyzed liquefaction of Zostera Marina and Enteromorpha Algae biomass. Based on isoconversional analysis...
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Bio-Based Polyurethane Composites and Hybrid Composites Containing a New Type of Bio-Polyol and Addition of Natural and Synthetic Fibers
PublikacjaThis article describes how new bio-based polyol during the liquefaction process can be obtained. Selected polyol was tested in the production of polyurethane resins. Moreover, this research describes the process of manufacturing polyurethane materials and the impact of two different types of fibers—synthetic and natural (glass and sisal fibers)—on the properties of composites. The best properties were achieved at a reaction temperature...
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Potential applications of crude glycerol in polymer technology–Current state and perspectives
PublikacjaThe increasing use of bio-based fuels and fuel additives, among them biodiesel, causes significant surplus of crude glycerol on the market which creates new challenges in terms of its sustainable utilization. A lot of ways for the incorporation of this by-product into different branches of industry requires purification by expensive and complicated processes. Therefore, researchers are seeking for applications of untreated crude...
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Enhancement of PUR/PIR foam thermal stability after addition of Zostera marina biomass component investigated via thermal analysis and isoconversional kinetics
PublikacjaIn the present work, a thorough thermogravimetric (TG) analysis of bio-based polyurethane–polyisocyanurate (PUR–PIR) foams in both nitrogen and oxygen atmosphere is performed. A sustainable element of the foam is a biopolyol obtained via acid-catalyzed liquefaction of Zostera marina and Enteromorpha Algae biomass. Based on isoconversional analysis and apparent activation energies, several conclusions are obtained. In contradiction...
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The Influence of Substitution of a Phosphorus-Containing Polyol with the Bio-polyol on the Properties of Bio-based PUR/PIR Foams
PublikacjaIn this work, effects of incorporating of a phosphorus-containing polyol into rigid polyurethane/polyisocyanurate foams’ formulations developed with use of two different bio-based polyols, derived from crude glycerol or liquefied cellulose were examined. The bio-polyol derived from crude glycerol was synthesized via two-step process from crude glycerol and castor oil, whereas the bio-polyol derived from liquefied cellulose was...
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Recent Progress on Hydrogen Storage and Production Using Chemical Hydrogen Carriers
PublikacjaDepleting fossil fuel resources and anthropogenic climate changes are the reasons for the intensive development of new, sustainable technologies based on renewable energy sources. One of the most promising strategies is the utilization of hydrogen as an energy vector. However, the limiting issue for large-scale commercialization of hydrogen technologies is a safe, efficient, and economical method of gas storage. In industrial practice,...
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Hydrogen Storage in Geological Formations—The Potential of Salt Caverns
PublikacjaHydrogen-based technologies are among the most promising solutions to fulfill the ze- ro-emission scenario and ensure the energy independence of many countries. Hydrogen is considered a green energy carrier, which can be utilized in the energy, transport, and chemical sectors. However, efficient and safe large-scale hydrogen storage is still challenging. The most frequently used hydrogen storage solutions in industry, i.e., compression...
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Study on the Structure-Property Dependences of Rigid PUR-PIR Foams Obtained from Marine Biomass-Based Biopolyol
PublikacjaThe paper describes the preparation and characterization of rigid polyurethane-polyisocyanurate (PUR-PIR) foams obtained with biopolyol synthesized in the process of liquefaction of biomass from the Baltic Sea. The obtained foams differed in the content of biopolyol in polyol mixture (0–30 wt%) and the isocyanate index (IISO = 200, 250, and 300). The prepared foams were characterized in terms of processing parameters (processing...
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Effect of bio-polyol molecular weight on the structure and properties of polyurethane-polyisocyanurate (PUR-PIR) foams
PublikacjaThe increasing interest in polyurethane materials has raised the question of the environmental impact of these materials. For this reason, the scientists aim to find an extremely difficult balance between new material technologies and sustainable development. This work attempts to validate the possibility of replacing petrochemical polyols with previously synthesized bio-polyols and their impact on the structure and properties...