SBA-15 samples functionalized with different arenesulfonic organic contents and prepared at 373 K were characterized by hyperpolarized 129Xe NMR spectroscopy. Variable-temperature measurements provide information on the organic groups distribution in the materials and on Xe diffusion in the mesopores. The heat of adsorption of xenon on the surface as well as its chemical shift value in interaction with the surface are deduced from the temperature dependence of the 129Xe chemical shift. The arenesulfonic group surface coverage was determined, and consequently, the “organic phase” contribution to the shielding constant was estimated. The evolution of the chemical shift with pressure allowed us to evaluate the “xenon−organic phase” interactions and hence distinguish the different organic contents. The slope of the pressure chemical shift dependence reveals the way in which the functionalization process took place. For low organic content (0.05 and 0.10), the slope is negative, indicating the presence of shallow micropores, while for high organic content (0.15 and 0.20), the chemical shift remains unchanged with the pressure showing that the modified mesoporous surface is homogeneous and micropores exempt. Information about the vicinity of Xe−organic phase are obtained from 129Xe−H CP and SPINOE experiments.

Hybrid inorganic-organic solid acid materials SBA-15-Ph-SO 3 H were synthesized by the directly cocondensation method under the acid medium. The resulting materials perform well both in the liquid phase Beckmann rearrangement (The yield is 32.3%) and esterification reaction (The yield is 95.5%). And more, the catalysts show the different catalytic performance in these two reactions.

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A thorough FTIR investigation of the thermal stability of arenesulfonic modified SBA-15 solids revealed that most of the organic functional groups are preserved until 400• C. These results have been confirmed by the thermogravimetric analyses of the corresponding materials calcined at 200• C (EC-200) or 400• C (EC-400), respectively. Such studies showed that the smoother calcination procedure (200 • C) is appropriate in order to complete the removal of Pluronic P123 in the extracted sample (E). Moreover, it can be noticed that such calcination treatment did not alter tremendously the catalytic performances of the resulting solids. Both E and EC-200 materials exhibited high activities in the liquid phase condensation of 2-methylfuran with acetone and in the decomposition of cumene hydroperoxide into phenol.