Pd nanoparticles supported on modified magnetic kaolin as a novel hydrogenation catalyst

Hydrogenation process is considered a vital and important step in the production of Poly-alpha-olefin oils. The development of novel catalytic systems is crucial for enhancing the efficiency of hydroprocessing. In recent decades, catalytic systems with magnetic separation have received immense attention. In work, we designed and synthesized a novel magnetic catalyst for the efficient hydrogenation of Poly-alpha-olefin oil. To achieve this, kaolinite was first magnetized and then functionalized with N-(2-aminoethyl)-3-aminopropyltrimethoxysilane and trichloro-1,3,5-triazine. To design an optimal support, a library of four amine compounds i.e., urea, thiourea, guanidine, and thiosemicarbazide was considered. Predictive computational results affirmed the superior interaction of thiosemicarbazide with palladium nanoparticles, making it an efficient ligand for stabilizing Pd nanoparticles. The prepared catalyst was fully characterized using ICP-AES, WAXS, TGA, FT-IR, VSM, SEM, and TEM analyses and applied for the hydro-finishing of Poly-alpha-olefin oil. In order to achieve optimal conditions, the effects of catalyst loading, hydrogen pressure and temperature as well as reaction time were surveyed. Gratifyingly, the resulting catalyst was a suitable candidate for the hydrogenation of Poly-alpha-olefin oil and exhibited superb performance under mild reaction conditions. The results indicated that 4 wt.% of the obtained catalyst could effectively promote the hydrogenation reaction at 130 °C for 7 h under hydrogen pressure of 7 bar, achieving a hydrogenation yield of 99 %. Furthermore, the catalyst demonstrated acceptable recyclability, retaining its activity with minimal Pd leaching after seven consecutive runs.