| Nitrides contained in petroleum may produce a significant effect on the property and stability of oil products. Serious atmospheric pollution can be caused by nitric oxides generated from burning nitrogen-containing fuels. In developed countries and some big cities in China NOx is one of the most primary air-pollutants, which is harmful to people and environment, and is also one of the items of air quality forecasting. The problem of creation of the chemical smog is a major concern we need pay attention to.This article invented a new denitrogenation method. Based on Lewis theory of acids and bases and similarity law, metal cation styrene resins, solid phase extraction sorbents, for basic nitrogen compounds removal from diesel fuel, were prepared. The results showed that adsorption capacity of Sr2+-cation resin was 9.10 mg·g-1 and the proper temperature of adsorption was 25℃. The widely used two-parameter Langmuir and Freundlich equations were inapplicable for this case. Coordination molar ratio of C5H5N to Sr(Ⅱ) was 1:1. The physical structure of the resin had a great effect on adsorption capacity.The kinetics and thermodynamics of the adsorption of C5H5N on Sr2+-cation resin were studied. Meanwhile, the corresponding determing-rate-steps were ascertained and diffusion coeffients were calculated. The results showed that the adsorption of C5H5N on Sr2+-cation resin was dominated by particle diffusion control (PDC)model if the concentration of C5H5N solution was larger than 100mg/L (D1= 5.01×10-7cm2s-1), otherwise, controlled by film diffusion control (FDC) if the concentration of C5H5N solution was less than 50mg/L (Kf=6.77×10-5 cms-1) within temperature range of 288.15K-298.15K. The adsorption was spontaneous for△G0=-3092KJ/mol, less than zero. The enthalpy△H0(KJ/mol) was found to be 110.8, indicating endothermal adsorption.The effects of height resin at the column (or H/D, i. e. ratio of height to diameter of resin column), flow rates of the diesel fuel samples on adsorption and the eluant of desorption, and the effects of composition, were studied. The suitable methods were also established about extraction, elution and regeneration in the resin column.Combustion of petroleum leads to the release of toxic sulfur dioxides into the environment, contributing significantly to air pollution and being the principal cause of acid rain, so crude oil needs to undergo desulfurization.Hydrodesulfurization (HDS), a chemical method, is a high pressure and high temperature catalytic process to reduce the sulfur in petroleum fractions to hydrogen sulfide. Hydrodesulfurization units are expensive to construct and to operate. On the other hand, biocatalytic progresses are cheap, operate under mild condition, and are endowed with high selectivity. This makes biodesulfurization (BDS) an alternative means in place of HDS for petroleum desulfurization.We do some research on Rhodococcus strain lawq, which has specific degradation ability of dibenzothiophene (DBT) in field of fermentation, desulfurization of resting cells and immobilized cells. The best carbon source, nitrogen source and sulfur source are glycerol were determined. We research on biodesulfurization of simulant system (DBT dissolve in water and ethanol). And the best reaction conditions of desulfurization of simulant system were determined.The samples of biodesulfurization of gasoline and diesel oil were provided by Yangzi company. The best conditions of gasoline desulfurization are as follows:the cell condition is 35 (A620), the ratio of water to gasoline is 8, the rotation speed is 200r/min, the reaction time is 32 h. Under the conditions, the ratio of desulfurization could reach 53%. The conditions of desulfurization of simulant system in FBR are as follows:the temperature is 35℃, pH is 7, the reaction time is 48 h, the quantity of immobilized cell is 50 g, the volume of solution is 150ml, the reactant concentration is below 5 mmol/L, the aerate is 60 ml/min. Under the condition, desulfurization rate could reach 30%.
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