Synthesis and Characterization of basic catalysts designed by Calixarenes or Silicas to take advantage of Glycerol

The growing concern about environmental issues and the allocation of environmental liabilities pose a significant challenge. A process of great importance in the Brazilian economy is the production of biofuels, produced from a reaction of transesterification of glycerides with an alcohol in the presence of a catalyst. In this reaction besides biofuel, there is a generation of a co-product, the glycerol, used in several sectors as a humectant, but this one may not be absorbed by the market. Routes to valorize glycerol have been increased by their conversion into glyceryl carbonate with the use of a basic catalyst, making the production chain of biofuels more sustainable and economically practicable. In this context, hybrids silica and calixarene-derived arise, whose preliminary tests with calix[4]arene depicted a frequency at 1784cm-1, on an IR spectrum, assigned to glyceryl carbonate, demonstrating their effectiveness when applied to the glycerol transcarbonation reaction. Calix[4]arene is a material belonging to the P121/n1 group being a widely crystalline material according to Figure 1, while the hybrid silicas are amorphous materials having pore structure organization. These materials are quite workable due to their thermal stability in the range of 78° C which is the temperature of the reaction medium.