| Sulfur compounds in fuel oils will pollute atmospheric after they were burned. Besides detrimental environmental effects of sulfur compounds, they also poison both catalytic conversion automobile catalysts and fuel cell reformer catalysts. With the growing demand of fuel oil, more stringent regulations have been mandated around the world to further reduce the sulfur level in fuels for purposes of environmental protection. Lower sulfur gasoline and diesel fuel oils have been an irresistible trend.However, the conventional hydrodesulfurization (HDS) process can no longer meet the requirement of deep desulfurization because it's difficult to remove the fused ring thiophene sulfides. Nowaday, selective adsorption for removing sulfur (SARS) is drawing attention worldwide. The key challenge of this approach is the development of adsorbents with a high adsorption capacity and selectivity for sulfur compounds over other aromatic and olefinic compounds. Among the various types of porous materials, zeolites are important alternatives as adsorbents due to its regular pore channel structure, large specific surface area, high ion-exchange and adsorption capacities as well as thermal and mechanical stabilities. In this paper, sorbents of NaY zeolite modified by Ni, Ce active components are selected as research object. Dibenzothiophenes (DBT) which was difficult to remove are selected as target contaminant of fuel oils. High sulfur removal and adsorption capacity materials for deep desulfurization were screened out.Firstly, the preparation methods and qualification of Ni serial sorbents and metal doping effects on sorbent's sulfur removal ability are studied. How the preparation factors affect sorbents'chemical and physical property is investigated by XRD, IR, ICP, TGA, et al. The experiment results show that when NaY is modified by 0.1 mol/L Ni (NO3)2 at 95℃, the DBT removal ability of NiY activated at 450℃is the highest.Static adsorption desulfurization of a model fuel on NiY zeolite had been carried out at different adsorption time and different fuel to sorbent ratio. When the conditions of adsorption desulfurization are 3 h and ratio of fuel and solid 0.02 g/mL, the result of desulfurization to DBT solutin is the best. Furthermore, the effect of NiY is better than NaY. Adsorption kinetics data of DBT on NiY was measred. Adsorption equilibrium data of DBT on NiY at 25℃was measured and simulated with Langmuir and Freundlic models. The Freundlic model adsorption equilibrium data was in good agreement with the calculated value. The results show that Freundlic adsorption model is suitable for describing characteristics of the system including DBT and NiY. The adsorption mechanism from a microscopic view is a synthetical action of the molecular sizes and the chemical bond.The investigations for selective adsorption of dibenzothiophene (DBT) over Ce/Ni-loaded Y zeolites with the emphasis on the effect of Ce as a cocation in the Ni-loaded Y zeolite are carried out in an attempt to produce more effective adsorbents for the desulfurization from transportation fuels. The promotional effects of Ce and coexisting toluene in the model fuel as well as contact time and adsorbent dose on the adsorptive performance were examined. The sorption data is varied according to both Langmuir and Freundlich isotherm models. The maximum sorption capacity by theoretically calculation is 22.2 mg/g at 25℃. The Langmuir constants b = 5.82 mL/mg and the Freundlich constants K = 1.042 L/mg and 1/n = 0.4 are evaluated. Ni/Celoaded Y zeolites (NiCeY) and NiY, CeY, NaY zeolites were used as adsorbents for the removal of DBT from model fuel containing 500 mg/L sulfur with 5 vol% of toluene by a batchmethod under ambient conditions. NiCeY exhibits higher adsorptive selectivity for DBT than NiY and CeY, indicating that NiCeY is a more effective adsorbent to remove sulfur compounds from transportation fuels.
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