Different amounts of FCC slurry oil and HVGO were added to Tahe atmospheric residue respectively. The colloi- dal stability and asphaltene agglomeration of atmospheric residue and mixed oils were characterized by mean...Different amounts of FCC slurry oil and HVGO were added to Tahe atmospheric residue respectively. The colloi- dal stability and asphaltene agglomeration of atmospheric residue and mixed oils were characterized by means of the mass fraction normalized conductivity and the small-angle X-ray scattering technology (SAXS). The results indicated that the sta- bility of Tahe atmospheric residue decreased with an increasing amount of these oil fractions. It was found that the decline of the colloidal stability was attributed to the component polarity difference between oil fractions and the atmospheric resi- due. Though the aromaticity of FCC slurry oil was higher than that of HVGO, the polarity of aromatics and resins of FCC slurry oil was lower than those of HVGO. So the degree of the colloidal stability was more seriously destroyed by FCC slurry oil. The dispersion of asphaltenes in Tahe atmospheric residue was changed by adding FCC slurry oil and HVGO. The particle size of as-ohaltenes increased alon~ with the decline of the colloidal stability展开更多
A modified mathematical model is used to study the effects of various forces on the stability of cavitation bubbles within a diesel droplet. The principal finding of the work is that viscous forces of fluids stabilize...A modified mathematical model is used to study the effects of various forces on the stability of cavitation bubbles within a diesel droplet. The principal finding of the work is that viscous forces of fluids stabilize the cavitation bubble, while inertial force destabilizes the cavitation bubble. The droplet viscosity plays a dominant role on the stability of cavitation bubbles compared with that of air and bubble. Bubble–droplet radius ratio is a key factor to control the bubble stability, especially in the high radius ratio range. Internal hydrodynamic and surface tension forces are found to stabilize the cavitation bubble, while bubble stability has little relationship with the external hydrodynamic force. Inertia makes bubble breakup easily, however, the breakup time is only slightly changed when bubble growth speed reaches a certain value(50 m·s-1). In contrast, viscous force makes bubble hard to break. With the increasing initial bubble–droplet radius ratio, the bubble growth rate increases, the bubble breakup radius decreases, and the bubble breakup time becomes shorter.展开更多
The composition, characteristics and preparation of ionic liquids are presented. The factors influencing the stability of gasoline and the significance of improving gasoline stability are discussed. A novel way to imp...The composition, characteristics and preparation of ionic liquids are presented. The factors influencing the stability of gasoline and the significance of improving gasoline stability are discussed. A novel way to improve the stability of gasoline by using ionic liquid catalyst is developed. The contents of olefin, basic nitrogen and sulfur in gasoline are determined and the optimal experimental conditions for improving gasoline stability are established.The ionic liquid catalyst, which is environmentally friendly, can reduce the olefin content in gasoline, and such process is noted for mild reaction conditions, simple operation, short reaction time, easy recycling of the ionic liquid catalyst and ready separation of products and catalyst.展开更多
基金Financial support was provided by the Ministry of Science and Technology of China through the National Basic Research Program (Grant No. 2010CB217807)
文摘Different amounts of FCC slurry oil and HVGO were added to Tahe atmospheric residue respectively. The colloi- dal stability and asphaltene agglomeration of atmospheric residue and mixed oils were characterized by means of the mass fraction normalized conductivity and the small-angle X-ray scattering technology (SAXS). The results indicated that the sta- bility of Tahe atmospheric residue decreased with an increasing amount of these oil fractions. It was found that the decline of the colloidal stability was attributed to the component polarity difference between oil fractions and the atmospheric resi- due. Though the aromaticity of FCC slurry oil was higher than that of HVGO, the polarity of aromatics and resins of FCC slurry oil was lower than those of HVGO. So the degree of the colloidal stability was more seriously destroyed by FCC slurry oil. The dispersion of asphaltenes in Tahe atmospheric residue was changed by adding FCC slurry oil and HVGO. The particle size of as-ohaltenes increased alon~ with the decline of the colloidal stability
基金Supported by the National Natural Science Foundation of China(51276011)the National High Technology Research and Development Program of China(2013AA065303)+1 种基金Beijing Municipal Natural Science Foundation of China(3132016)the Opening Foundation of State Key Laboratory of Engines(K2013-3)
文摘A modified mathematical model is used to study the effects of various forces on the stability of cavitation bubbles within a diesel droplet. The principal finding of the work is that viscous forces of fluids stabilize the cavitation bubble, while inertial force destabilizes the cavitation bubble. The droplet viscosity plays a dominant role on the stability of cavitation bubbles compared with that of air and bubble. Bubble–droplet radius ratio is a key factor to control the bubble stability, especially in the high radius ratio range. Internal hydrodynamic and surface tension forces are found to stabilize the cavitation bubble, while bubble stability has little relationship with the external hydrodynamic force. Inertia makes bubble breakup easily, however, the breakup time is only slightly changed when bubble growth speed reaches a certain value(50 m·s-1). In contrast, viscous force makes bubble hard to break. With the increasing initial bubble–droplet radius ratio, the bubble growth rate increases, the bubble breakup radius decreases, and the bubble breakup time becomes shorter.
文摘The composition, characteristics and preparation of ionic liquids are presented. The factors influencing the stability of gasoline and the significance of improving gasoline stability are discussed. A novel way to improve the stability of gasoline by using ionic liquid catalyst is developed. The contents of olefin, basic nitrogen and sulfur in gasoline are determined and the optimal experimental conditions for improving gasoline stability are established.The ionic liquid catalyst, which is environmentally friendly, can reduce the olefin content in gasoline, and such process is noted for mild reaction conditions, simple operation, short reaction time, easy recycling of the ionic liquid catalyst and ready separation of products and catalyst.