Coal-derived liquid asphaltenes diffusion and adsorption in supported hydrotreating catalysts

► Adsorption and diffusion of coal asphaltenes on hydroconversion catalysts. ► Mesoporous pore size effect on coal asphaltene diffusion. ► Effective diffusivities vary from 5 × 10−12 to 3 × 10−11 m2/s for different pore sizes. ► The size of coal asphaltene aggregate is smaller than the petroleum asphaltene one. ► The increase of pore size tends to increase the performance of coal liquid upgrading.