Modification of activated carbon and its adsorption property of thiophene

Adsorption is one of the most promising methods in deep desulfurization of gasoline.The activated carbon was modified by HNO3 oxidation,calcinations and loading with metallic ions.the desulfurization performance of the activated carbons was evaluated by adsorptive removal of thiophene from thiophene-cyclohexane binary solution with equilibrium adsorption capacity as the criterion for evaluation.The experimental results show that the surface acidity groups of activated carbon increase considerably by HNO3 treatment and improve its desulfurization performance;The desulfurization rate of modified activated carbon increased through calcinations under N2 atmosphere;loading of Fe,Zn,Cu,Ni ion on the activated carbon improved its adsorption of thiophene,while modified by Fe ion gave the higher desulfurization rate than by other metal ions.Then,the effect of different modification method combination on the activated carbon are studied.The complex modification of active carbon,oxidized firstly by HNO3 before loading active component,its desulfurization efficiency greatly enhanced,and then impregnated by Fe ion,gave the highest desulfurization rate,which could reach 85%for the thiophene.