Palladium/carbon nanotubes/charcoal hybrid composite and its catalytic behavior in the hydrogenation of trans cinnamaldehyde

Title : Palladium/carbon nanotubes/charcoal hybrid composite and its catalytic behavior in the hydrogenation of trans cinnamaldehyde

Abstract:

In  the  present  study,  we  addressed  the  palladium  (Pd)  decoration  of  multiwalled  carbon  nanotube (CNT)/activated  carbon  (AC)  hybrid  composites  (MWCNT/AC),  and  examined  the  catalytic  behavior  of  the composites in the hydrogenation of trans-cinnamaldehyde. The MWCNT/AC composites were prepared by growing CNT network on the surface of AC granules, using the chemical vapor deposition method. XPS analysis revealed that the  MWCNT/AC  and  COOH–MWCNT/AC  composites  and  isolated  AC  adsorbed  Pd  at  different  oxidation  states when   dipped   into   a   Pd   microemulsion:   isolated   AC   and   the   COOH–MWCNT/AC   composite   adsorbed   Pd nanoparticles at di- and tetravalent states (Pd2+/4+), while the MWCNT/AC composite adsorbed Pd nanoparticles at zero  and  tetravalent  states  (Pd0/Pd4+).  The  MWCNT/AC  composite  may  thereby  have  hierarchical  Pd  adsorption properties dependent on the MWCNT network type grown onto the AC surface. Regarding the catalytic performance, the  (Pd0/4+)-MWCNT/AC  catalyst  displayed  higher  selectivity  to  hydro-cinnamaldehyde  formation  (95.9%)  when compared  with  the  (Pd2+/4+)-AC  and  (Pd2+/4+)-COOH–MWCNT/AC  catalysts  (72.1%  and  91.4%  selectivity, respectively). The catalytic performance of the (Pd0/4+)-MWCNT/AC catalyst with 2.8 wt% of Pd loading was also superior than the catalytic performance of commercial catalysts with 5 and 10 wt% of Pd loading and other Pd/CNTs catalysts reported in the literature.

Biography:

Elaine Matsubara holds a BA (2002) in Chemistry, PhD (2010) in Science from the University of São Paulo (USP), a part of her PhD studies from the Instituto de Ciencias de Los Materiales de Madrid - Spain, Italian National Agency for New Technologies Energy and Sustainable Economic Development, and University of Rome La Sapienza - Italy. She is presently PhD researcher at University of São Paulo (USP), Brazil. Her work focuses on synthesis of doped carbon nanotubes, 3D hybrid hierarchical carbon nanomaterials and graphene for energy devices applications.  Her experience is focuses on energy devices and nanocomposites to filtration, catalysis, environmental remediation and polymer reinforcement.