Glycerol transesterification by heterogeneous catalysis: the way to a sustainable process

NANCY BÁLSAMO; EIMER GRISELDA ; MONICA CRIVELLO

Foz do Iguazú

Conferencia; 4º IUPAC Conference in Green Chemistry; 2012

The sensibility for environmental protection has increased in the public, political and economical world, because quality of life is strongly connected to a clean environment. The strongest impulse for developing new, more efficient and selective catalyst systems and for the realization of new process technology is strongly related to environmental compatibility. Layered materials, with their structure consisting of stacked sheets, represent an interesting opportunity for developing new materials with a tailored nano-design. Layered double hydroxides (LDHs), also referred as hydrotalcite-like compounds or anionic clays, are a family of lamellar solids having the general formula [M(II)1-x M(III)x(OH)2](An-)x/n.mH2O. Their structure is based on brucite-like layers in which a fraction of the divalent metal cations (MII) have been substituted by trivalent cations (MIII) resulting in positively charged layers balanced by anions in the interlayer. Calcination of LDHs leads to formation of metal mixed oxides. This work reports the synthesis and characterization of metal mixed oxides obtained from precursors like LDHs, where a constant fraction of Mg was substituted by Ba and Ca. These oxides were catalytic evaluated in the selective glycerol (biodiesel by-product) transesterification to monoglycerides.