Non⁃metallic pipeline has become the new direction of oil and gas pipeline technology because of its excellent performance. However, the electrostatic problem during the oil transportation process threatens the safe operation of pipeline. Based on diffuse double layer theory, the electrostatic electrification mechanism of metal and nonmetallic pipes is analyzed and compared. The effects of flow regime, pipe properties and oil properties on the oil flow electrification are systematically elucidated. The main forms and hazards of electrostatic discharge of oil pipeline are analyzed in detail. Moreover, a series of electrostatic control and hazard protection measures are put forward from the perspectives of avoiding electrostatic generation and neutralizing static electricity.

Four graphiticlike carbon nitride materials (CNEDACTC,CNDCD, CNUREA, CNMEM) have been synthesized with ethylenediaminecarbon tetrachloride, dicyandiamide, urea and melamine as precursors, using attapulgite (ATP) as hard template. The new materials were characterized by XRD and TG, besides which, the N ₂ and CO ₂ absorption properties were tested repectively. The results indicated that the structure and properties of the precursors played an important role in the adsorption capacity of carbon nitride materials. In the four materials, the CNUREA exhibited the highest capacity of CO ₂  with a capacity of 85.438 cm3/g at 0 ℃ and 58.931 cm3/g at 25 ℃. In addition, the results showed the attapulgite used as template in the new materials was removed thoroughly under magnetic stirring condition in 5% HF. The pore volumes and the CO ₂ absorption capacity of the samples were improved obviously.

The adsorptiondesorption isotherms of thiophene and benzene in the NiY and NiY/Beta zeolites, prepared by liquid phase ion exchange, have been investigated by an intelligent gravimetric analyzer (IGA) and the diffusion coefficients were also calculated. Properties of selective adsorptive desulfurization of FCC gasoline on the zeolites were evaluated by a fixedbed adsorption experiment. The results show that the NiY/Beta zeolites remain the microporous structure. The saturated adsorption amount of thiophene is larger than that of benzene and so it is to the diffusion coefficients. The better diffusivity of thiophene inhibits the adsorption of benzene, resulting in the absorption desulfurization capability of the NiY/Beta zeolites improved.