Study On The Adsorbents For Remove Sulfur In FCC Gasoline

The properties of different adsorbents for remove sulfur in FCC gasoline were studied. The total sulfur in the gasoline was measured using burning-lamp method and the amount of hydrogen sulphide was determined with acidic cadmium sulphate. The amount of mercaptan was determined by electric potential titration and the thio-ether was measured by complexometric titration with mercury nitric. Preparation condition, adsorption time, ratio of adsorbent to gasoline etc. were studied at normal temperature and atmospheric pressure in static experiment. The desulfurization results showed that it's the type, surface polarity, relative surface area, structure and SiO2/Al2O3 (molecule sieves) of adsorbent affect the desulfurization. For the same type adsorbent, the degree of desulfurization increases with the increase of relative surface area, porosity and amount of weak acid. The most effective adsorbent is molecule sieves, the worst one are Al2O3 and cation resin. The desulfurization capability of HZSM-5, USY, 13X and 5A for mercaptan is USY>13X>HZSM-5>5A. The Pyridine-TPD results showed that their desulfurization capability should contribute to weak acidity sites. HZSM-5,USY, active clay and Y -Al2O3 were modified by different metal cations. The most effective modify metal is Fe and the alkali metals gave the worst results. The proper content of Fe on USY is about 1%. l%Fe-USY was used in the dynamic experiment. The suitable rate of highness/diameter is 5, WHSV is about l.0h-1 and the capability of adsorbent is about 1.15mg/g. Adsorbent was impregnated by water before baked is better than baked directly when the adsorbent was regenerated.