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• NiO nanoparticles supported TiO 2 catalysts are prepared via sol-gel method. • Octahedrally coordinated NiO nanoparticles are well dispersed on the support. • Acetylation of glycerol is performed under non-microwave instant heating condition. • 90% conversion and 66% selectivity of triacetyl glyceride is achieved. • No significant catalyst deterioration after four successive runs. NiO-supported TiO 2 (n NiO/TiO 2) as highly active and selective catalysts for triacetyl glyceride (TAG) biofuel additive production via acetylation of glycerol is reported. The catalysts are prepared by incorporating various amounts of Ni2+ (n = 10, 30 and 50 wt% Ni added during catalysts preparation) onto the TiO 2 support using simple sol-gel approach followed by calcination. The spectroscopy and microscopy analyses reveal that the NiO nanoparticles (ca. 6 nm) are uniformly distributed on the surface of TiO 2 support where octahedrally coordinated NiO as active species is formed upon calcination. Among the catalysts prepared, 30NiO/TiO 2 with strongest acidity and highest accessible surface area is found to be the most active in the acetylation of glycerol with acetic acid, achieving 90.2% glycerol conversion with 65.9% selective to TAG under non-microwave instant heating conditions (170 °C, 30 min). In addition, 30NiO/TiO 2 also shows better catalytic performance than previous reported catalysts. No significant deterioration in catalytic activity is shown by 30NiO/TiO 2 after eight successive runs, thus offering a green pathway for synthesizing TAG vehicle fuel additives with high selectivity. [ABSTRACT FROM AUTHOR]