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Showing 1 to 13 of 13 for “"Subcritical water"”.
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Development of Green Subcritical Water Separation Technology
Theoretically speaking, water under temperature and pressure conditions below its critical point is called subcritical water. However, the term “subcritical water” normally refers to hot water up to 374 C and pressure up to 218 atm. As the temperature increases, the hydrogen bonding between water …
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Fundamental solubility study of polycyclic aromatic hydrocarbons in subcritical water and ethanol mixtures
Water is increasingly being used as a processing medium as a consequence of the current emphasis for sustainable processes. At relatively high temperatures and pressures, water acts as a good solvent, resulting in a number of potential applications. A lack of fundamental data, however, has limited …
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Analysis and Treatment of Emerging Polar Contaminants
… a major focus as sources of contamination of water systems. Pharmaceuticals and personal care products (PPCPs) enter water through wastewater streams, and many of these compounds survive current wastewater treatment processes. High production volume chemicals (HPVCs), defined as chemicals …
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Upgrading biomass by hydrothermal and chemical conditioning
… biomass is treated with hot compressed subcritical water (200-260oC) for 5 min-8 h. The solid product, HTC biochar, contains about 55-90% of the mass and 80-95% of the fuel value of the original feedstock. The HTC process takes any wet waste biomass and converts it to a homogenized, …
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Exposure and Characterization of Candidate Materials for Use in Supercritical Water Reactors
The use of supercritical water as the heat transfer medium between a power source and the steam generating system lead to an increase in thermodynamic efficiency. Supercritical water systems have already been employed in fossil fuel power generation, and a proposed Gen IV nuclear reactor is …
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Comparison of Nitronic 50 and Stainless Steel 316 for use in Supercritical Water Environments
… One such design employs supercritical water, which in addition to high temperatures and pressures is also highly oxidizing. A critical understanding of both mechanical and oxidation characteristics of candidate materials are required to determine the viability of materials for these …
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Lignin Transformation and Characterization of Pyrolytic Products
… metal oxide catalysts (CoO, LaO, and MoO) with subcritical water at 200°C and 240°C were used to convert lignin to value-added aromatic monomers. Separation of the resulting organic and aqueous phases was done by liquidliquid extraction using ethyl acetate. Our results indicate the formation of …
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The influence of fungi upon soil structure and soil water relations
… of soil structural stability and soil water processes was assessed through the application of laboratory investigations and a field based analysis. The impact of an arbuscular mycorrhizal (AM) fungal exudate glomalin (a glycoprotein), proposed to be hydrophobic was assessed for a …
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Hydrothermal Liquefaction of Municipal Sludge: Feedstock Composition, Inorganic Interactions, and Co-Liquefaction as a Dewatering Alternative
Wastewater treatment plants in the United States generate several million dry tons of sewage sludge each year, and the conventional disposal pathways (landfilling, incineration, and land application) present challenges, particularly with the rise of contaminants like per- and polyfluoroalkyl …
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Hydrothermal Carbonisation of Novel Biomasses
… (HTC) is a technology wherein biomass exposed to subcritical water at 180 °C – 260 °C is thermochemically converted into an energy-dense “hydrochar” with strong thermal and elemental similarities to fossil coal. However, key aspects of the HTC reaction remain unknown, especially with regard to the …
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EXPLOITATION OF ANTIOXIDANT BIOACTIVE COMPOUNDS FROM AGRO-INDUSTRIAL BY-PRODUCTS
… scolymus) leaf by-products; − Salvia desoleana water residue from essential oil production (plant steam-distillation); − Caper (Capparis spinosa L.) brine residue from salty flower buds’ production. Once the agro-industrial by-products were selected, the study focused on identifying the best …
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Supercritical Technologies for the Valorization of Wine Industry By-Products
… from grape skins and defatted grape seeds using subcritical water (SW) and then, modeling of the kinetics of extractions and process economic analysis. The overall objective of the work is to develop recovery strategies for wine-making wastes in order to reduce their environmental impact and to …
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Valorization of industrial solid residue from macroalgae by emerging technologies
Uno de los principales problemas que afronta la sociedad actual es la acumulación de residuos, consecuencia de una creciente población y una mayor calidad de vida. Sin embargo, el concepto de biorrefinería, donde los residuos son tratados como nuevas materias primas que puedan ser reincorporadas al …