| dc.description.abstract | The thesis is divided into two parts. In the first part, carboxylic acid functionalized mesoporous benzene-silica (BC-X materials, X refers to the [CES /(CES + BTEB)] molar ratio) have been synthesized with Brij 76 as the structure-directing agent under acidic conditions via co-condensation of 1,4-bis(triethoxysilyl)benzene (BTEB) and carboxyethylsilanetriol sodium salt (CES). The BC-X materials are ordered and uniformed mesoporous with a high loading of carboxylic acid groups (up to 80 mol% based on silica). In this study, a varief of techniques was adopted to characterized the BC-X materials, including transmission electron microscopy (TEM), scanning electron microscopy (SEM), 13C CP-MAS NMR, 29Si MAS NMR , nitrogen sorption measurements, thermogravimetric analyzer (TGA), Fourier transform infrared spectrometer (FTIR) and powder X-ray diffraction (XRD).
In the second part, the BC-X samples with high loadings of carboxylic group is therefore acted as adsorbents for the removal of methylene blue. The adsorption process is carefully studied with various systematic factors, including the loading amount of CES, the quanity of methylene blue, temperature and pH of adsorption system. Due to the high surface area, good affinity of arboxylic groups and pi-pi interaction of benzene rings, the BC-X materials exhibits excellent performance on methylene blue adsorption. The experimental data for the adsorption were analyzed using Freundlich and Langmuir isotherm models. It is found that the Langmuir equation provides an accurate description of these adsorption data, suggesting that monolayer adsorption occurred in all cases of the performed sorption processes.
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