الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Since the publication of the first paper on mesoporous silica; i. e., FSM-16 and M41S, their meso-structures in presence and absence of various metal oxides considered much attention from chemical and material science point of view because of their applications in catalysis, adsorption, sensors and separations. The formations of meso-structured materials have been promoted by a micelle-templating method including electrostatic charge-matching and electrical neutral pathways using surfactants as a Structure Directing Agent. Immobilized catalysts are of great interest for environmentally benign synthesis in point of view of green and sustainable chemistry. Generally, complexes immobilized on organic supports (polystyrene, polyacrylic acid ...etc) are not suitable for oxidation reactions, as aggressive oxidants can easily ruin the weak C-H bonds in these polymers. On the other hand, inorganic supports, such as silica, zeolite and clay, are providing thermally, chemically and mechanically stable reaction sites. These supports have been often utilized for various catalytic reactions due to their high surface area, appropriated pores size and not affected by various catalysts. Moreover, mesoporous silica, FSM, has been reported to form a chlorophyll-FSM conjugate, exhibiting photo-induce ability to catalyse the reduction of methyl viologen, where mesoporous FSM acts as a site of interaction between the chlorophyll molecule and the silica support. Ruthenium porphyrin complexes immobilized into FSM have been reported as efficient catalysts for epoxidation of olefins. This study was considered as an effective application and development for a new and simple application utilizing solid chemosensor synthesized from mesoporous silica nanospheres and using a ligand embedded novel sensor, these ligands - which was successfully anchored onto the highly ordered mesoporous silica-are Dimethylglyoxime (DMG), for visual detection and removal of nickel (Ni(II)) ion, and 8- Hydroxyquinoline (8-HQ), for colorimetric detection and removal of V(II) ions in petroleum products and contaminated wastewater. The new sensors showed an optically colored signal that was readily created and transported even at trace concentrations of detected ions. Ions sensing responses using the novel sensor recorded to be up to nanomolar concentrations (∼0.22 μg/L) for Ni(II) ions and (∼0.15 μg/L) for V(II) ions with immediate response time (in seconds). Therefore, the sensors were simple, effective tool for the fast, sensitive, selective, inexpensive, and specific recognition of a broad range of the detected ions optically. The adsorption capacity was determined and the data were well fitted by the Langmuir adsorption isotherm equation. Interference of competing ions with the detecting ions was studied, and the results indicated the high selectivity towards the detected ions at optimum condition, and the adsorbent was successfully captured the detecting ions even the petroleum samples of naphtha, jet fuel, gas oil, fuel oil. Both two novel sensors can be used easily with multiple regeneration/reuse cycles, by using diluted HCl acid to remove target ions from the used sensors efficiently and formed “metal-free” sensors again. In spite of that petroleum products contain active constituents; the sensors were simple, effective, fast, sensitive, selective, inexpensive, and specific recognition of a broad range of the ions optically. These sensors when used to detect ions in petroleum products, ex. Coker gasoline indicated that it can be an alternative tool to a time and cost saving effective laboratory assays.