Sustainable synthesis and characterization of cobalt-based biocatalysts from olive stone waste for enhanced curing of unsaturated polyester resins

The functionalization of native olive wood shell stone for the formation of new active heterogeneous cobalt-based biocatalysts has been conducted. The resulting biocatalysts have been fully characterized using various analytical techniques, including X-ray fluorescence (XRF), elemental analysis, granulometry, X-ray photoelectron spectroscopy (XPS), Fourier-Transform Infrared Spectroscopy (FTIR), thermogravimetry (TGA), moisture content, field-emission scanning electron microscopy (FESEM) and high-angle annular dark-field imaging (HAADF) with energy dispersive X-ray spectroscopy (EDX). The catalytic performance of these new functional heterogeneous materials has been verified by gelation time measurements on a multipurpose unsaturated polyester/styrene/tert-butyl peroxybenzoate system. The results are compared with those obtained using the current workhorse of the industry, which utilizes cobalt-based catalysts, particularly cobalt octoate dissolved in a solvent solution known to have adverse environmental and human health implications.