Biotechnological fabrication of LaMnO3-carbon catalyst for n-butanol conversion to ketones

An attempt to synthesize a hybrid carbon-based material for catalytic purposes was made using a biotechnological approach. The material consists of a carbon matrix in which LaMnO3 nanocrystallites are dispersed. The perovskite-type oxide crystallites were synthesized in the carbon matrix by the transformation of lanthanum and manganese salts, which penetrated the living tissues of a plant due to the natural transport of metal ions. Cellulose/lignin rich plant stems were carbonized at 600-800 degrees C for 1-22 h, yielding a microporous carbon matrix in which nanocrystallites of the complex oxide were uniformly distributed. The plant (Salix viminalis) was selected because of its high tolerance to heavy metal ions. The formation of carbon matrix from organic precursor is a key factor in the synthesis of the complex inorganic nanocrystallites of high dispersion. The hybrid carbon-based materials were tested as catalysts for unconventional conversion of n-butanol to heptanone-4. The catalysts exhibited high selectivity and product yield, despite the extremely low content of LaMnO3 (0.3% atomic). The paper proves that catalysis-oriented functionalization of carbons may begin at a very early stage through chemical modification. (C) 2009 Elsevier Ltd. All rights reserved.