Extraction, supercritical fluids, lignin

Supercritical fluid solvents have been tested for reactive extractions of liquid and gaseous fuels from heavy oils, coal, oil shale, and biomass. In some cases the solvent participates in the reactions, as in the hydrolysis of coal and heavy oils with water. Related applications include conversion of cellulose to glucose in water, dehgnincation of wood with ammonia, and liquefaction of lignin in water. 

Supercritical Fluid Extraction of Lignin from Wood... 

Supercritical fluid extraction is a new separation technique that finds a number of applications in the natural products, biochemicals, food, pharmaceuticals, petroleum, fuel, and polymer industries (1-8). There is now an interest in applying this technology in the pulp and paper industry (9,10). In a recent comprehensive study on the interaction of supercritical fluids with lignocellulosic materials, it has been shown that lignin can be not only extracted from wood by reactive supercritical fluids but also separated as solid products in solvent-free form by reducing the extraction fluid pressure from a supercritical to sub critical level (11,12). 

Li kiran Supercritical Fluid Extraction cf Lignin from Wood 49... 

To compare lignins produced from supercritical fluid extraction of wood with lignins from conventional pulping processes, a kraft pine lignin... 

Li, L. Kiran, E. Supercritical fluid extraction of lignin from wood. In Lignin Properties and Materials, ACS Symposium Series 397 Glasser, W.G., Sarkenen, S., Eds. ACS Washington, DC, 1989 42-57. 

Reyes T, Bandyopadhyay S, McCoy B (1989) Extraction of lignin from wood with supercritical alcohols. J Supercrit Fluids 2(2-3) 80-84... 

Pasquini, D., Pimenta, M. T. B., Ferreira, L. H., Curvelo, A. A. S. Extraction of lignin from sugar cane bagasse and Finns taeda wood chips using ethanol-water mixtures and carbon dioxide at high pressures. The Journal of Supercritical Fluids 2005, 36, 31-39. 

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