Superior FeNi3-FeOx/Ni-foam catalyst for gas-phase hydrogenation of dimethyl oxalate to ethanol

A high-performance Ni-foam-structured FeNi3-FeOx nanocomposite catalyst is developed for the ethanol (EtOH) synthesis from syngas via gas-phase dimethyl oxalate (DMO) hydrogenation. The hydrothermally-synthesized Ni (OH)(2)/Ni-foam was impregnated with aqueous solution of iron(III) nitrate, from which the preferred FeNi3-FeOx/Ni-foam-(550/350) catalyst was obtainable by calcining preferably at 550 degrees C (to adequately form NiFe2O4NiO composites) and subsequently reducing in H-2. Such catalyst is capable of fully converting DMO with 98 % ethanol selectivity at 230 degrees C and 2.5 MPa using a WHSVDMO of 0.44 h(-1) and a H-2/DMO molar ratio of 90, and particularly, being stable for at least 700 h. A high turnover frequency of 88.8 h(-1) is achieved at 180 degrees C. Exactly, our NiFe2O4-NiO derivation strategy endows the catalyst with plentiful interface between FeNi3 nanoalloy (similar to 16 nm) and FeOx fragments (acting as acid sites), achieving synergistic catalysis to ester groups in DMO and as-formed hydroxyl groups, thereby markedly improving its hydrogenation to EtOH.