Digestate-derived pyrolytic oil blended with diesel typically reduces combustion efficiency and worsens emissions. This study explores the combined use of TiO 2 nanoparticles and hydrogen (H 2 ) gas to improve engine performance and emission outcomes in a single-cylinder diesel engine. Optimization enabled performance to slightly exceed that of conventional diesel, while particulate matter and CO emissions decreased by 56% and 35%, respectively; however, NO x emissions rose from 1164 to 1344 ppm. Combustion stability improved markedly, with the coefficient of variation dropping from 32% to 15%. Life cycle assessment showed a 52% reduction in global warming potential and an energy return on investment of 2.8:1. At an H 2 flow rate of 20 L min −1 , the system achieved an optimal balance between performance and emissions. Molecular dynamics simulations revealed that TiO 2 enhances oxidation by promoting interactions with fuel molecules, supporting cleaner combustion and reduced soot formation. • Digestate-based pyrolysis oil with 20 L min −1 H 2 and 100 ppm TiO 2 achieved BTE than neat diesel. • PM decreased by 56% and CO by 35%, while NO x rose moderately from 1164 to 1344 ppm. • LCA showed 52% reduction in GWP and an energy return on investment of 2.8:1. • MD simulations revealed TiO 2 catalyzes oxidation and soot decomposition.
Maroušek et al. (Thu,) studied this question.