Y₂O₃-Inserted Co-Pd/zeolite catalysts for reductive amination of polypropylene glycol

다국어 초록 (Multilingual Abstract)

<P><B>Abstract</B></P> <P>Cobalt-based catalysts having different base strengths were prepared by controlling the amount of yttrium oxide (Y<SUB>2</SUB>O<SUB>3</SUB>). These catalysts were used for the facile one-pot synthesis of polyetheramine (PEA) from polypropylene glycol (PPG) through reductive amination. It is noticed that high hydrogen partial pressures up to 40 bar inhibit the formation of cobalt nitride and lead to a high PEA yield although it has been known that dehydrogenation from alcohol to ketone is the rate-determining step. The Y<SUB>2</SUB>O<SUB>3</SUB>-inserted Co-Pd/Molecular sieve13X catalyst also showed high activity toward PEA even at low hydrogen partial pressure. Y<SUB>2</SUB>O<SUB>3</SUB> played a crucial role in giving basicity to the catalyst, which not only prevents the formation of cobalt nitride but also promotes hydrogenation of imine to amine at a wide range of H<SUB>2</SUB> pressure. Thus Y<SUB>2</SUB>O<SUB>3</SUB> inserted Co-Pd/Molecular sieve 13X provides unique performance toward enhancing the PEA yield while suppressing the catalyst deactivation caused by the cobalt nitride formation.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Y<SUB>2</SUB>O<SUB>3</SUB>–Inserted Co-Pd catalysts were prepared for reductive amination. </LI> <LI> The catalysts led to 99% PEA yield from PPG via a facile one-pot synthesis. </LI> <LI> The Y<SUB>2</SUB>O<SUB>3</SUB>-inserted catalysts inhibit Co<SUB>3</SUB>N but promote hydrogenation of imine. </LI> <LI> Basicity of Y<SUB>2</SUB>O<SUB>3</SUB> hinders NH<SUB>3</SUB> access into the cobalt surface of the catalysts. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>