Adsorption calorimetry: Energetic characterisation of the surface of mesoporous silicas and their adsorption capacity of non-linear chain alcohols

Mesoporous solids SBA-15, SBA-16, MCM-41 and MCM-48 were synthesised using standard procedures. The products were characterised by powder X-ray diffraction (XRD) and diffuse reflectance Fourier transform infrared (DRIFT). The adsorption isotherms of nitrogen were measured at -196 degrees C. Adsorption isotherms of different nonlinear alcohols were also measured at different temperatures and were adjusted to the hybrid Dubinin-Astakov (DA) model for inhomogeneous surfaces. The results obtained show that this model is valid for the polar molecules investigated. Measurement of adsorption microcalorimetry using different non-linear alcohols on mesoporous silicas was carried out. The results of differential adsorption enthalpies with these alcohols are associated with the heterogeneity surface of silicas prepared and their structure porosity. This work shows that the adsorption microcalorimetry is a promising technique to assess the energy characteristics of mesoporous solids. (C) 2015 Elsevier B.V. All rights reserved.