A method of removing sulfur compounds from a hydrocarbon fluid. The method includes contacting the hydrocarbon fluid with an adsorbent comprising a carbonaceous material doped with nanoparticles of uranyl oxide (UO3) to reduce the concentrations of the sulfur compounds. The carbonaceous material is at least one selected from the group consisting of activated carbon and carbon nanotubes, and the adsorbent has a weight ratio of C to U in the range from 9:1 to 17:1, and a weight ratio of C to O in the range from 5:1 to 13:1.