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Articulo 3 quimica agro pdf

C R Chimie ?? Account Revue Carbohydrates as green raw materials for the chemical industry Frieder W Lichtenthaler Siegfried Peters Clemens-Sch? pf-Institut für Organische Chemie und Biochemie Technische Universit? t Darmstadt Petersenstra? e Darmstadt Germany Received August accepted February This review is dedicated to Professor Gérard Descotes in recognition of his basic contributions towards utilization of carbohydrates as organic raw materials Abstract In view of the impending transition of chemical industry from depleting fossil raw materials to renewable feedstocks ?? the end of cheap oil is predicted for at the latest ?? this account gives an overview on chemically transforming low-molecular weight carbohydrates into products with versatile industrial application pro ?les and the potential to replace those presently derived from petrochemical sources To cite this article F W Lichtenthaler S Peters C R Chimie ? Académie des sciences Published by Elsevier SAS All rights reserved Résumé Du fait de l ? imminence de la mutation de l ? industrie chimique vers l ? utilisation de matières premières renouvelables à la place des ressources fossiles ?? l ? épuisement de ces ressources bon marché est prévu pour au plus tard ?? cet article propose une vue générale de la transformation chimique des sucres à faible poids moléculaire vers des applications industrielles polyvalentes et de leur potentiel à remplacer les produits préparés actuellement à partir de ressources pétrochimiques Pour citer cet article F W Lichtenthaler S Peters C R Chimie ? Académie des sciences Published by Elsevier SAS All rights reserved Keywords Carbohydrates Biofeedstock Industrial utilization Organic chemicals Mots clés Sucres Biomasse Utilisation industrielle Produits chimiques organiques Introduction As our fossil raw materials are irrevocably decreasing and as the pressure on our environment is building up the progressive changeover of chemical industry to Corresponding author E-mail address lichtenthaler chemie tu- darmstadt de F W Lichtenthaler renewable feedstocks for their raw materials emerges as an inevitable necessity ?? i e it will have to proceed increasingly to the raw materials basis that prevailed before natural gas and oil outpaced all other sources Historically the raw materials basis was substantially renewable as depicted in Fig with the utilization of biomass and coal being in equal about years ago In the s coal tar-based materials had ? Académie des sciences Published by Elsevier SAS All rights reserved doi j crci C F W Lichtenthaler S Peters C R Chimie ?? natural gas oil coal renewable feedstocks year Fig Raw materials basis of chemical industry in historical perspective taken the lead reaching a maximum around thereafter fossil gas and oil irresistibly took over eliminating coal nearly completely and reducing renewable feedstocks to very modest levels This over-reliance of chemical industry on fossil raw materials has its foreseeable limits as they are depleting and are irreplaceable the only question being when will a ?ordable fossil fuels be exhausted Or stated more appropriately when will fossil raw materials have become so expensive that biofeedstocks are an economically competitive alternative Experts realistically predict the end of cheap oil for