The feasibility of gas phase deposition using a Ti alkoxide precursor for precise surface modification of catalysts was demonstrated by modifying a mesoporous alumina support with a Ti oxide overcoat.Titanium tetra-isopropoxide yields a Ti oxide layer that covers homogeneously the alumina surface.Uniformity of the deposited TiO2 was verified by SEM-EDX, on both intra-particle and inter-particle levels.Only a few at. layer deposition (ALD) cycles were required in order to obtain Ti contents with a relevance for industrial application.The pore size distribution of the overcoated catalyst support was barely affected by the coating process.Synthesized CoMo catalysts based on the Ti-alumina carrier showed up to 40% higher activity compared to a catalyst supported on pristine alumina, in hydroprocessing under industrial testing conditions.The TiO2 coating appeared to be stable, showing no agglomeration characteristics after reaction as corroborated by TEM-EDX.ALD provides a scalable route with low waste generation for the production of precisely structured TiO2-Al2O3 hydroprocessing catalyst supports.
