Development of hafnium-silica solid Lewis acids for γ-valerolactone production from biobased levulinic acid

abstract

There is growing awareness of the need to expand the gamma-valerolactone (GVL) market within the biobased economy, although challenges remain in developing sustainable, green processes. In this work, the biobased top platform chemical, levulinic acid (LA), was converted to GVL under relatively mild conditions, via catalytic transfer hydrogenation (CTH) routes, using solid Lewis acid catalysts consisting of morphologically distinct EPDM and LFS type silicas and hafnium. The catalyst development was based on important requirements for process feasibility and involved several post-synthesis strategies and introduction of Hf-sites via different methods to meet superior performances. Complementary structural and molecular-level characterisation techniques were employed together with catalytic and kinetic modelling/computational studies for studying the influence of the material properties on the catalytic performances for targeting GVL. The developed heterogeneous catalysts contributed to enhanced productivity (up to 87% GVL yield, at 180 degrees C), were stable in consecutive runs, and also seemed promising in terms of the E factor. EPDM and LFSs were never investigated before for biomass conversion processes or any other catalytic system, to the best of our knowledge.

keywords

CATALYTIC TRANSFER HYDROGENATION; HIGHLY EFFICIENT CATALYST; HIERARCHICAL Y; BETA ZEOLITES; BIOMASS; ZSM-5; CONVERSION; DESILICATION; ADSORPTION; REDUCTION

subject category

Chemistry

authors

Antunes, MM; Khan, K; Neves, P; Fernandes, A; Andrulevicius, M; Ribeiro, F; Valente, AA

Groups

G1 - Porous Materials and Nanosystems
G4 - Renewable Materials and Circular Economy

Projects

CICECO - Aveiro Institute of Materials (UIDB/50011/2020)

CICECO - Aveiro Institute of Materials (UIDP/50011/2020)

Associated Laboratory CICECO-Aveiro Institute of Materials (LA/P/0006/2020)

Rede Nacional de Ressonância Magnética Nuclear (PTNMR)

acknowledgements

This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020 (DOI 10.54499/UIDB/50011/2020), UIDP/50011/2020 (DOI 10.54499/UIDP/50011/2020) & LA/P/0006/2020 (DOI 10.54499/LA/P/0006/2020), financed by national funds through FCT/MCTES (PIDDAC), UIDB/00100/2020 (DOI 10.54499/UIDB/00100/2020), UIDP/00100/2020 (DOI 10.54499/UIDP/00100/2020) and LA/P/0056/2020 (DOI 10.54499/LA/P/0056/2020) in the scope of CQE-IMS (Centro de Quimica Estrutural, Institute of Molecular Sciences). The positions held by M. M. A. and A. F. were funded by national funds (OE), through FCT, I. P., in the scope of the framework contract foreseen in the numbers 4, 5 and 6 of article 23 of the Decree-Law 57/2016 of 29 August, changed by Law 57/2017 of 19 July (for M. M. A.: https://doi.org/10.54499/DL57/2016/CP1482/CT0062). The NMR spectrometers are part of the National NMR Network (PTNMR) and are partially supported by Infrastructure Project No. 022161 (co-financed by FEDER through COMPETE 2020, POCI and PORL and FCT through PIDDAC). The authors greatly acknowledge the AGC Si-Tech Co., Ltd. company for kindly supplying the three commercial samples, EPDM-10, LFS-50 and LFS-150.