CaO Supported on Porous Carbon as Highly Efficient Heterogeneous Catalysts for Transesterification of Triacetin with Methanol

A series of carbon-supported CaO materials, prepared using different porous carbon materials as supports, were tested as basic catalysts for the transesterification of triacetin with methanol and characterized by means of X-ray diffraction (XRD), N 2 adsorption, temperature-programmed desorption (TPD), and X-ray photoelectron spectroscopy (XPS). It was found that all of the carbon-supported CaO catalysts are active for the transesterification reaction, and their catalytic performance can be influenced by a variety of factors, such as the types of carbon supports, the concentration of impregnated CaO, the heat-treated temperatures of the catalysts, and the reaction temperatures. Particularly, the supported CaO catalyst, which is prepared using a kind of porous carbon (NC-2) as a support, exhibits very high activity, stability, and recyclability. We suppose that the main characteristics of this porous carbon, such as the presence of relatively abundant surface oxygen-containing functional groups and well-developed porosity, may be beneficial to build a suitable interaction between CaO particles and the carbon support, thus resulting in the formation of an active and stable catalyst system.