Preparation And Performance Of Petroleum-Coke Based Activated Carbon Composites For Fuel Oil Deep-desulfurization

Deep desulfurization of fuel oils is very important in that it can upgrade fuel oil quality and reduce urban air pollution, which is a hot topic in recent years. Activated carbons were prepared from petroluem coke by a two step steam activation method using nickel as a catalyst, which were loaded with different amounts of Ni-Zn under the same Ni/Zn molar ratio of 0.5 using an incipient wetness impregnation method. Both the activated carbons and metal loaded ones were used as adsorbents for the purpose of deep desulfurization of fuel oils. Results indicate that the activated carbons and their metal loaded ones are typical microporous materials. The activation temperature is the most influential factor that determine the sulfur adsorption capacity among the activation conditions (temperature, time and steam/coke ratio) employed under ambient conditions. The adsorption capacity of all adsorbents investigated increases with the initial concentration of dibenzothiophene and observes the Langmuir adsorption model. The adsorption performance of the Ni-Zn loaded activated carbons is remarkable under hydrogen aided chemical adsorption. The cumulative adsorption capacities below 10ppm of outlet oil for the activated carbon loaded with 1.56 and 3.91 mmol (Ni+Zn)/g-activated carbon are 48.1 and 106.5 mgS/g-adsorbent under 360℃, a H2/oil ratio of 0.1 mol/mol, a liquid space velocity of 1 h-1 and an initial sulfur concentration of 640ppm from ethylthiophene, which corresponds to a metal utilization ratio of 96.1 and 85.45%, respectively. The performance of this metal loaded adsorbents is superior to the commercial adsorbent, S-Zorb.