Basic solids like CaO and MgO supported on alumina [24], and
hydrotalcites [25] have been used for biodiesel production from
vegetable oils. To avoid diffusion limitations, catalysts with higher
surface area (porous silica-metal oxide composites) were tested
in the transerification of vegetable and animal oils providing high
conversion to (C10–C30) alkyl methyl esters and glycerin