L'accès à l'eau potable est indispensable au développement de la vie. La pollution, liée aux activités anthropiques, constitue une menace pour la santé humaine et pour les espèces sauvages. Parmi les nombreux polluants retrouvés dans les eaux, la pollution par les métaux lourds constitue un problème environnemental d'intérêt mondial en raison de leur toxicité élevée, même à des concentrations très faibles, et de leur persistance dans la nature. De nombreuses méthodes peuvent être mises en oeuvre pour l'élimination des métaux lourds dans l'eau. Parmi elles, les procédés d'adsorption sont très attractifs car très efficaces et peu couteux. Les zéolithes sont des matériaux bien connus pour leurs propriétés d'échange. Les matériaux mésoporeux modifiés ou adsorbants carbonés sont également très attractifs du fait de leur importante surface spécifique. Dans ce manuscrit, les performances d'adsorption de cations métalliques en phase aqueuse sur des matériaux mésoporeux, silices SBA-15, SBA-16, KIT-6 modifiées par l'EDTA et carbone CMK-3 obtenu par réplication ont été étudiées et comparées avec celles de la zéolithe NaX. Les propriétés physico-chimiques de l'ensemble des matériaux ont été caractérisées par plusieurs techniques d'analyses. L'influence des paramètres expérimentaux (pH, temps de contact, température, concentration des ions métalliques et de la présence d'ions concurrents) sur l'adsorption a été étudiée en mode batch. L'efficacité de ces matériaux a également été étudiée dans un réacteur dynamique à lit fixe. Les résultats obtenus ont montré que tous les matériaux étudiés éliminent efficacement et rapidement les métaux divalents dans les eaux même à faible concentration. Néanmoins, le carbone CMK-3 s'avère être le meilleur adsorbant du fait de sa grande capacité d'adsorption même en présence d'espèces compétitrices. / Access to sustainable and clean drinking water is a main concern as the Earth's human population continues its steady growth. Unfortunately, many of the available water resources are becoming increasingly polluted as a result of the direct discharge of industrial effluents. Heavy metals pollution, in particular, is an environmental problem of global interest due to their high toxicity, even at very low concentrations, and persistence in nature. Many methods are available for metal ions removal including adsorption which is attracting a lot of attention recently. Zeolites are well known for having very high exchange capacities. On the other hand, many researchers are studying the removal of heavy metals by modified mesoporous materials or carbonaceous adsorbents. In this thesis, the adsorption efficiencies of several materials for heavy metal removal in aqueous phase were investigated and compared to those of the faujasite NaX zeolite. Mesoporous silica SBA-15, SBA-16, KIT-6 were synthesized and modified with EDTA. Moreover, CMK-3 carbon was nano-casted from SBA-15 then the physic-chemical properties of these materials were characterized by different techniques. The effects of several experimental conditions on adsorption such as pH, contact time, temperature, metal ions concentration and the presence of competitors were studied in batch experiments. Then the efficiency of all these materials was also studied in a dynamic fixed bed reactor. Based on the obtained results, it could be said that all these materials are good candidates for divalent heavy metals removal from waste water even at low concentration. However, CMK-3 material has a high sorption capacity even in presence of competitor species.

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New catalyst development for the hydrotreating process, employing functionalized mesoporous carbon (mC) support is studied. mC support was prepared by the volume templating of alkali modified SBA-15 using sucrose as the carbon source and then functionalized using nitric acid of various concentrations (upto 8M HNO3). A series of NiMo catalysts (12% Mo and 2.4% Ni) were prepared using these functionalized mC supports. The supports and catalysts were characterized by N2 physisorption, SAXS, XRD, FTIR, TGA, SEM, TEM, H2-TPR and HRTEM. SAXS results indicated mild reduction in ordered structure of mesoporous carbons after functionalization. N2 physisorption analysis indicated progressive reduction in surface area and pore volume with the increase in nitric acid concentration. Enhancement of surface functional groups and acidity after functionalization were observed through FTIR spectroscopy and Boehm titration. SEM images showed the retention of needle like morphology in all functionalized carbon supports. TEM images showed that the increase in nitric acid concentration causes excessive etching, resulting in the reduction of ordered structure of functionalized mesoporous carbons. Hydrotreating study of these NiMo/mC catalysts were carried out under industrial operating conditions in a laboratory scale trickle bed reactor using coker light gas oil derived from Athabasca bitumen as feedstock. NiMo catalyst supported on 6M acid treated mC (i.e. NiMo/mC-6M) showed the highest activity due to higher surface functional groups, higher acidity and better textural properties. The HDS and HDN activities of NiMo/mC-6M catalyst were higher than that of NiMo/ã-Al2O3 catalyst owing to lower support metal interaction (SMI), higher surface area and effective functionalization. Using the mC-6M support, NiMo catalysts with different metal loading (12 27% Mo, 2.4 to 5.4% Ni) were prepared and characterized. Hydrotreating activity study of these catalysts indicated that the catalyst with 22% Mo and 2.9% Ni loading was the optimum catalyst on 6M functionalized mC support. Higher metal loading (>22%Mo) led to excessive pore blockage and improper metal dispersion resulting in decreased activity. Kinetic study of the optimum catalyst was carried out by varying temperature (330°C to 370°C), gas-to-oil ratio (400 1000 Nm3/m3), LHSV (1.0 to 2.5 hr-1) and pressure (7.8 to 9.8 MPa) and the data was fitted by non-linear regression method using power law model. The calculated reaction orders and activation energies were 2.8, 1.5 and 189 KJ/mol, 98.9 KJ/mol for HDS and HDN, respectively. The results of HRTEM and H2-TPR indicated lower SMI in mC supported catalyst resulting in the generation of qualitatively Type-II like NiMoS phase on functionalized mC supports, which is considered to be very active for hydrotreating. The hydrotreating activity of the optimum catalyst was higher than that of commercial catalyst (supported on ã-Al2O3). Long term deactivation experiment carried out over a total period of 10 weeks confirmed the durability of NiMo/mC catalyst for the duration of operation. This study reveals the immense capability of functionalized mC supports to become the potential alternative catalyst support to conventional ã-Al2O3 for the hydrotreating of gas oil feedstocks.

New catalyst development for the hydrotreating process, employing functionalized mesoporous carbon (mC) support is studied. mC support was prepared by the volume templating of alkali modified SBA-15 using sucrose as the carbon source and then functionalized using nitric acid of various concentrations (upto 8M HNO3). A series of NiMo catalysts (12% Mo and 2.4% Ni) were prepared using these functionalized mC supports. The supports and catalysts were characterized by N2 physisorption, SAXS, XRD, FTIR, TGA, SEM, TEM, H2-TPR and HRTEM. SAXS results indicated mild reduction in ordered structure of mesoporous carbons after functionalization. N2 physisorption analysis indicated progressive reduction in surface area and pore volume with the increase in nitric acid concentration. Enhancement of surface functional groups and acidity after functionalization were observed through FTIR spectroscopy and Boehm titration. SEM images showed the retention of needle like morphology in all functionalized carbon supports. TEM images showed that the increase in nitric acid concentration causes excessive etching, resulting in the reduction of ordered structure of functionalized mesoporous carbons. Hydrotreating study of these NiMo/mC catalysts were carried out under industrial operating conditions in a laboratory scale trickle bed reactor using coker light gas oil derived from Athabasca bitumen as feedstock. NiMo catalyst supported on 6M acid treated mC (i.e. NiMo/mC-6M) showed the highest activity due to higher surface functional groups, higher acidity and better textural properties. The HDS and HDN activities of NiMo/mC-6M catalyst were higher than that of NiMo/ã-Al2O3 catalyst owing to lower support metal interaction (SMI), higher surface area and effective functionalization. Using the mC-6M support, NiMo catalysts with different metal loading (12 27% Mo, 2.4 to 5.4% Ni) were prepared and characterized. Hydrotreating activity study of these catalysts indicated that the catalyst with 22% Mo and 2.9% Ni loading was the optimum catalyst on 6M functionalized mC support. Higher metal loading (>22%Mo) led to excessive pore blockage and improper metal dispersion resulting in decreased activity. Kinetic study of the optimum catalyst was carried out by varying temperature (330°C to 370°C), gas-to-oil ratio (400 1000 Nm3/m3), LHSV (1.0 to 2.5 hr-1) and pressure (7.8 to 9.8 MPa) and the data was fitted by non-linear regression method using power law model. The calculated reaction orders and activation energies were 2.8, 1.5 and 189 KJ/mol, 98.9 KJ/mol for HDS and HDN, respectively. The results of HRTEM and H2-TPR indicated lower SMI in mC supported catalyst resulting in the generation of qualitatively Type-II like NiMoS phase on functionalized mC supports, which is considered to be very active for hydrotreating. The hydrotreating activity of the optimum catalyst was higher than that of commercial catalyst (supported on ã-Al2O3). Long term deactivation experiment carried out over a total period of 10 weeks confirmed the durability of NiMo/mC catalyst for the duration of operation. This study reveals the immense capability of functionalized mC supports to become the potential alternative catalyst support to conventional ã-Al2O3 for the hydrotreating of gas oil feedstocks.