Breaking water-in-oil emulsions during the refining of crude oils is an important step before any upgrading process is started.Asphaltene molecules are incriminated as playing an important role in this phenomenon.Unra...Breaking water-in-oil emulsions during the refining of crude oils is an important step before any upgrading process is started.Asphaltene molecules are incriminated as playing an important role in this phenomenon.Unraveling the mechanisms behind the affinity between them and water is a key step to understand how to break these emulsions more easily and require lower amounts of demulsifiers.Choosing which demulsifier molecule(s)to use is also primordial,but to do so rationally,one needs to know which are the molecular interactions in place between asphaltenes,porphyrins and water so that demulsifiers are chosen to destabilize a specific physical–chemical interaction.In this paper,we study the interactions arising between asphaltenes and porphyrins and six different molecules potentially displaying a demulsification action in the presence of water/oil interfaces.We demonstrate that the ionic demulsifier molecules present an interesting potential to either interact strongly with water,replacing asphaltenes in this interaction,or to interact with the active sites of asphaltenes,deactivating them and avoiding any asphaltenic interfacial activity.Finally,we also found that although asphaltenes do not migrate spontaneously toward the water/oil interfaces,porphyrins do so rather easily.This indicates that porphyrins do have an important activity at the water/oil interface.展开更多
In order to promote convenient strategies for the utilization of wood wastes from aucoumea klaineana pierre(okoume)timber industry,various chemical analysis were carried out on samples from different origins.Total ext...In order to promote convenient strategies for the utilization of wood wastes from aucoumea klaineana pierre(okoume)timber industry,various chemical analysis were carried out on samples from different origins.Total extractives content of the bark,sapwood and heartwood of okoume were evaluated.thermogravimetric analyses were performed and the stiasny number was calculated.it was found that the bark was richer in fatty acid of high molecular weight while the sapwood was rich in fatty acid of low molecular weight.the condensed tannins content varied according to the origin and the part of the tree.these new findings should be useful for green okoume based tannin adhesives.展开更多
基金the DN (Direction du Numé-rique) from Universitéde Pau et des Pays de l’Adour,MCIA (Mésocentre de Calcul Intensif Aquitain),GENCI-CINES (Grant 2017-c2016087698) for providing the computation power needed for this projectIsifor-Carnot Institute and Total Refining&Chemicals are also acknowledged for their financial support to this research project
文摘Breaking water-in-oil emulsions during the refining of crude oils is an important step before any upgrading process is started.Asphaltene molecules are incriminated as playing an important role in this phenomenon.Unraveling the mechanisms behind the affinity between them and water is a key step to understand how to break these emulsions more easily and require lower amounts of demulsifiers.Choosing which demulsifier molecule(s)to use is also primordial,but to do so rationally,one needs to know which are the molecular interactions in place between asphaltenes,porphyrins and water so that demulsifiers are chosen to destabilize a specific physical–chemical interaction.In this paper,we study the interactions arising between asphaltenes and porphyrins and six different molecules potentially displaying a demulsification action in the presence of water/oil interfaces.We demonstrate that the ionic demulsifier molecules present an interesting potential to either interact strongly with water,replacing asphaltenes in this interaction,or to interact with the active sites of asphaltenes,deactivating them and avoiding any asphaltenic interfacial activity.Finally,we also found that although asphaltenes do not migrate spontaneously toward the water/oil interfaces,porphyrins do so rather easily.This indicates that porphyrins do have an important activity at the water/oil interface.
文摘In order to promote convenient strategies for the utilization of wood wastes from aucoumea klaineana pierre(okoume)timber industry,various chemical analysis were carried out on samples from different origins.Total extractives content of the bark,sapwood and heartwood of okoume were evaluated.thermogravimetric analyses were performed and the stiasny number was calculated.it was found that the bark was richer in fatty acid of high molecular weight while the sapwood was rich in fatty acid of low molecular weight.the condensed tannins content varied according to the origin and the part of the tree.these new findings should be useful for green okoume based tannin adhesives.
