Renewable N-doped active carbons as efficient catalysts for direct synthesis of cyclic carbonates from epoxides and CO2

A1 Originalartikel i en vetenskaplig tidskrift (referentgranskad)


Interna författare/redaktörer


Publikationens författare: Ajaikumar Samikannu, Lakhya Jyoti Konwar, Päivi Mäki-Arvela, Jyri-Pekka Mikkola
Publiceringsår: 2019
Tidskrift: Applied Catalysis B: Environmental
Tidskriftsakronym: Appl. Catal., B
Volym: 241
Artikelns första sida, sidnummer: 41
Artikelns sista sida, sidnummer: 51
eISSN: 1873-3883


Abstrakt

In the spirit of green chemistry and greenhouse gas mitigation, we explore herein the chemical utilization of CO2 upon synthesis of cyclic carbonates over N-doped activated carbons. The N-doped carbocatalysts were obtained from inexpensive N-rich bio-waste precursors and characterized by standard techniques (N2 physisorption, chemisorption, XPS, SEM, TEM, XRD, FT-IR and Micro-Raman spectroscopy). The materials exhibited excellent catalytic activity for direct carbonation of epoxides with CO2 to cyclic carbonates (yields upto 99%) under solvent free, moderate temperature (100–150 °C) and low CO2 pressure (5–50 bar) conditions. The observed catalytic activity of the N-doped carbocatalysts was attributed to the Lewis basic sites originating from pyridinic, pyridonic, and quaternary N-sites capable of activating the CO2 molecule. While control experiments with multiwalled carbon nanotubes (MWCNT) or commercial activated carbon, failed to produce cyclic carbonates due to lack of active (basic) sites. In terms of the catalytic performance, the N-doped carbocatalysts presenting a high porosity (634–1316 m2/g) and high levels of pyridinic (33%) and quaternary N-doping (30%), (i.e. CA500 and MA500), exhibited the highest activity and selectivity (TOF, conversion and cyclic carbonate yields upto 99% in 5–15 h). Most importantly, these materials demonstrated good operational stability and reusability.


Nyckelord

Chemical Engineering

Senast uppdaterad 2019-16-12 vid 04:29