This project aims to develop a novel method for the transformation of lignin and chitosan into valuable metal-free nitrogen(N)- and/or sulphur(S)-containing carbonaceous photocatalysts. New catalytic materials possessing excellent sonophotocatalytic redox properties to assist continuous flow photo-redox processes in obtaining high-value chemicals from bio-oil-based molecules upgrading. The objective is to prepare metal-free carbon-based photocatalytic materials through the physicochemical effects of low/high-frequency sonication (e.g., effective mass transfer, microstreaming, cross-linked radical polymerization, etc, effects often inaccessible through conventional methods) as a promising pre-treatment step before ending the synthesis of the materials under hydro(solvo)thermal conditions. It will be carried out the study of the physicochemical properties of carbon-based materials (before and after (sono)-(photo)-catalytic test reactions), and testing them in the selective sonophotocatalytic oxidation and C-C sonophoto-reductive coupling of bio-oil-inspired model compounds (in flow liquid-phase) as a futuristic approach of bio-oil-based molecules valorization. Systematic basic research of the effect of green and unconventional source of ultrasonic energy on the pre-treatment of chitosan (precursor of C, N, O) and lignin (precursor of C, S, O, aromaticity) and its effect on the final material obtained after optimization of hydro(solvo)thermal conditions, will be carried out. To get insight into the mechanism of ultrasound-assisted hydro(solvo)thermal method, the whole spectrum of materials characterization techniques and basic kinetic studies and photocatalysts’ stability/recycling studies (using the appropriate flow (sono)-(photo)-reactors) will be carried out. The use of ultrasound-based procedures offer a facile, versatile synthetic tool for the preparation of nanophotocatalysts, often inaccessible through conventional methods.
Project title: “Nanoengineering of multicomponent metal-free carbonaceous materials for bio-oil upgrading through ultrasound-assisted selective redox photocatalysis in continuous-flow reactors”.
Financed by the National Science Centre in Poland. OPUS-20 project number 2020/39/B/ST5/00076. https://www.ncn.gov.pl/konkursy/wyniki/2021-05-20-opus20-preludiumbis2-sonata16
Project leader: Prof. Dr. Juan Carlos Colmenares Quintero