Catalytic performance of low loading palladium-carbon catalyst in rosin disproportionation: Characterization, process enhancement, and reaction pathway

Abstract

This study introduces an efficient Pd/C catalyst for the rosin disproportionation (RD) reaction, a key biomass conversion process. The low-loaded Pd/C catalysts, with 3–6 nm Pd nanoparticles, were synthesized via deposition-precipitation and characterized for their high dispersion of metallic Pd on activated carbon. Optimized using the Box-Behnken design of response surface methodology, the catalyst achieved a 71.36 % maximum DAA yield under optimal conditions (280 °C, 150 min, 0.04 wt% catalyst, 3.00 wt% Pd), surpassing commercial catalysts by 1.27 times with reduced Pd usage. Key factors for catalytic activity included Pd loading, dispersion, particle size, and metallic Pd content. Kinetic studies showed an activation energy of 21.52 kJ/mol for the conversion of abietic acid to dehydroabietic acid, highlighting the superior potential in the RD reaction. Ultraviolet-visible absorption spectra and gas chromatography-mass spectrometry analyses elucidated the reaction pathway and mechanism, providing a practical approach to developing high-activity catalysts for industrial RD applications.