Furfural obtained from pentose containing biomass such as hemicelluloses is subjected to photooxygenation. The resulting hydroxyfuranone obtained in high yields undergoes acetalization with fatty alcohols. Using NaHSO 3 , surfactants are obtained by addition of a sulfonate group to α,β-unsaturated carboxyl or carbonyl compounds. Addition occurred either at the CvC double bond (6) or at the aldehyde function (7). Compared to conventional surfactants of this type, the resulting compounds possess similar good detergent properties. In the case of compound family 6 and when compared to the corresponding alkylsulfate and alkylsulfonate surfactants, even lower critical micelle concentrations (CMC) are observed. Biodegradation of the new surfactants was determined according to the OECD Test guideline 301 F. Compounds of family 6 are biodegradable. Biodegradation of compounds of family 7 stopped after 10 days.
The oxidation of starch, xylans, potato flesh and wheat flour by H(2)O(2), in the presence of MSO(4) (M=Cu, Fe) as catalyst, led to depolymerization, and formation of solutions containing polyhydroxycarboxylic acids. Some of these oxidized compounds facilitate the process, leading to efficient transformations even with very low amounts of catalyst.
Current regulations require the substitution of toxic solvents by safer ones. Succinic acid diesters, which are among promising bio-based candidates, have been compared to petrochemical solvents through two complementary approaches. The first one deals with a prediction of solvents dissolution power based on Hansen Solubility Parameters (HSP). HSP values obtained with the model developed by Stefanis-Panayiotou showed good agreement with experimental miscibility maps. The second one explores the physicochemical properties with multivariate statistical methods. Principal Components Analysis and Agglomerative Hierarchical Clustering led to a partition of green solvents into clusters together with toxic solvents, suggesting favourable substitutions in further applications.
IFP Energies nouvelles International Conference Rencontres Scientifiques d'IFP Energies nouvellesRe´sume´-É tude de l'effet de tensioactifs sur la de´formation et le de´tachement de gouttes d'huiles mode`les a`l'aide d'une cellule a`flux laminaire -Les tensioactifs « verts » a`teˆte polaire de´rive´e de sucre (glucose, pentose) sont de plus en plus pre´sents dans les formulations de´tergentes en raison des re´glementations en vigueur et des demandes des consommateurs. Dans le but d'e´tudier le pouvoir de´tergent de ces nouvelles mole´cules, le comportement de gouttes d'huiles mode`les soumises a`un flux de solution de´tergente de concentration variable, a e´te´e´tudie´a`l'aide d'une cellule a`flux laminaire et corre´le´aux proprie´te´s physicochimiques des syste`mes aux interfaces liquide/liquide et solide/liquide/liquide. Trois comportements principaux ont e´te´observe´s à partir d'une valeur critique du de´bit de de´tergent : un e´talement, un fractionnement de la goutte ou bien son de´tachement spontane´de la surface. L'analyse des re´sultats a montre´une corre´lation entre le comportement de la goutte et l'e´quilibre des forces s'exerc¸ant sur la goutte dans sa position initiale (avant l'application du flux), en particulier en conside´rant la force de gravite´, qui tend a`de´tacher la goutte de la surface, et la force capillaire, qui tend a`maintenir sa forme sphe´rique. Un diagramme d'e´tat a pu eˆtre e´tabli, permettant de pre´dire le comportement de la goutte, en fonction du nombre de Bond (rapport des forces de gravite´sur les forces capillaires) et du cosinus de l'angle de contact de la goutte dans sa position initiale. Les re´sultats obtenus ont permis de comparer les performances de diffe´rents tensioactifs en termes de de´graissage et d'illustrer le potentiel des AlkylPolyPentosides (APP) pour cette application.Abstract -Effect of Surfactants on the Deformation and Detachment of Oil Droplets in a Model Laminar Flow Cell -Sugar-based surfactants are increasingly present in the development of ecofriendly detergents due to current regulations and consumer demand. In order to assess the degreasing performance of these new surfactants, the behavior of model oil droplets subjected to the action of a flow of surfactant solutions of different concentrations was studied in a laminar flow cell and related to the physico-chemical properties measured at the liquid/liquid (interfacial tension) and solid/liquid/liquid interfaces (contact angle). With the surfactant solutions and the model oils employed in this study, three main behaviors were observed when a critical flow rate was reached: elongation, fragmentation or spontaneous detachment of the droplet. The analysis of the results leads to a correlation between the droplet behavior and the balance of the forces applied on the droplet in
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