. "Text" . "The aim of this thesis was to study the influence of acid-base properties of support on the structure and activity of the sulfide Mo and CoMo phases of hydrotreating catalysts. Boron and magnesium were chosen as additives to modify the acidity properties of alumina in an opposite but consistent way. The results indicated that the electronic deficiency of the Mo and CoMo sulfide phase varied in parallel with the Br\u00F8nsted acidity and electronegativity of the supports. On boron modified catalysts, the increase of the electronic deficiency of the sulfide phase led to higher hydrogenation properties in HDS and HDN reactions. However, on Mg series catalysts, the variation of the electronic properties of the sulfide phase can not totally explain the performance of the catalysts. The observations were interpreted from other aspects. The beneficial effect of B and Mg can be combined by their co-addition. Finally, an electric model was established to account for the relationship between support properties and the electronic properties of the sulfide Mo phase." . . "Catalyse h\u00E9t\u00E9rog\u00E8ne" . "Ce travail a pour objectif de d\u00E9terminer l\u2019influence des propri\u00E9t\u00E9s acido-basique du support sur la structure et l\u2019activit\u00E9 de catalyseurs d\u2019hydrotraitement. L\u2019addition de bore ou de magnesium \u00E0 l\u2019alumine a permis de modifier de mani\u00E8re continue, contr\u00F4l\u00E9e et oppos\u00E9e les propri\u00E9t\u00E9s du support. Les r\u00E9sultats montrent que la d\u00E9ficience \u00E9lectronique de la phase sulfure est li\u00E9e \u00E0 la pr\u00E9sence des sites acides de Br\u00F8nsted ainsi qu\u2019\u00E0 l\u2019\u00E9lectron\u00E9gativit\u00E9 du support. Sur les catalyseurs contenant du bore la d\u00E9ficience \u00E9lectronique de la phase sulfure augmente les propri\u00E9t\u00E9s hydrog\u00E9nantes du catalyseur en HDS et en HDN. Toutefois sur la s\u00E9rie de catalyseurs dop\u00E9s au Mg, la variation des propri\u00E9t\u00E9s \u00E9lectroniques ne peut pas totalement expliquer les performances du catalyseur. D\u2019autres facteurs doivent \u00EAtre impliqu\u00E9s. Par ailleurs, les effets b\u00E9n\u00E9fiques du bore et du magn\u00E9sium peuvent \u00EAtre combin\u00E9s. Enfin, un mod\u00E8le \u00E9lectronique a \u00E9t\u00E9 propos\u00E9 pour rendre compte des relations entre l\u2019acidit\u00E9 du support et les propri\u00E9t\u00E9s \u00E9lectroniques de la phase sulfure." . . . . "2009" . . . "Influence of acid-base properties of support on the properties of sulfided Mo and CoMo/Al2O3 hydrotreating catalysts, modification of the support by addition of B or Mg" . "Spectroscopie infrarouge" . . "Catalyseurs d'hydrotraitement" . . "Sulfures" . . . "Influence des propri\u00E9t\u00E9s acido-basiques de l'alumine sur la structure et l'activit\u00E9 de catalyseurs d'hydrotraitement, \u00E9tude de l'effet de l'addition de bore et de magn\u00E9sium" . . "Influence des propri\u00E9t\u00E9s acido-basiques de l'alumine sur la structure et l'activit\u00E9 de catalyseurs d'hydrotraitement, \u00E9tude de l'effet de l'addition de bore et de magn\u00E9sium" . . "Alumine" . "Monoxyde de carbone" . "Th\u00E8ses et \u00E9crits acad\u00E9miques" . . . . . "\u00C9lectron\u00E9gativit\u00E9" . .