Stringent regulations and environmental concerns make the production of clean fuels with low sulfur content compulsory for the petroleum refining industry.Because of ease of operation without high energy consumption,t...Stringent regulations and environmental concerns make the production of clean fuels with low sulfur content compulsory for the petroleum refining industry.Because of ease of operation without high energy consumption,the adsorption of sulfur compounds seems the most promising process.Central composite design was used to optimize parameters influencing the synthesis of dispersed carbon nanoparticles（CNPs）,a new class of sorbents,in order to obtain an excellent adsorbent for desulfurization of liquid fuel.The optimized dispersed CNPs,which are immiscible in liquid fuel,can effectively adsorb different benzothiophenic compounds.Equilibrium adsorption was achieved within 2 min for benzothiophene,dibenzothiophene,and 4,6-dimethyldibenzothiophene with removal efficiency values of 75 %,83 %,and 52 %,respectively.The rate of desulfurization by the prepared CNPs in the present work is seven times higher than the previously reported CNPs.Optimized CNPs were characterized by different techniques.Finally,the effect of the mass of CNPs on the removal efficiency was studied as well.展开更多
The as-sintered sinter skin and the polished section of WC-11Co-0.4Cr 3 C 2-0.3VC-0.2RE（RE=mischmetal with La/Ce ratio of 0.65） alloy were analyzed.It was shown that the microstructures on the skin and in the inner ...The as-sintered sinter skin and the polished section of WC-11Co-0.4Cr 3 C 2-0.3VC-0.2RE（RE=mischmetal with La/Ce ratio of 0.65） alloy were analyzed.It was shown that the microstructures on the skin and in the inner part of the alloy were all characterized with a WC＋β＋M structure,where β was a cobalt-based binder phase and M represented a RE-containing phase.There existed an inward diffusion of S atoms,which caught and fixed the Ce atoms in the alloy and an outward diffusion of La atoms during the sintering process.Consequently,the M phase was characterized with the decreased La/Ce ratio（0.59） in the inner part and the increased La/Ce ratio（1.01） on the skin.The M phase on the skin was characterized with a γ-Ce 2 S 3 type structure.To suppress the long range migration of rare earth to the skin,S in the sintering atmosphere had to be eliminated.展开更多
基金financial support from Bu-Ali Sina University was gratefully acknowledged
文摘Stringent regulations and environmental concerns make the production of clean fuels with low sulfur content compulsory for the petroleum refining industry.Because of ease of operation without high energy consumption,the adsorption of sulfur compounds seems the most promising process.Central composite design was used to optimize parameters influencing the synthesis of dispersed carbon nanoparticles（CNPs）,a new class of sorbents,in order to obtain an excellent adsorbent for desulfurization of liquid fuel.The optimized dispersed CNPs,which are immiscible in liquid fuel,can effectively adsorb different benzothiophenic compounds.Equilibrium adsorption was achieved within 2 min for benzothiophene,dibenzothiophene,and 4,6-dimethyldibenzothiophene with removal efficiency values of 75 %,83 %,and 52 %,respectively.The rate of desulfurization by the prepared CNPs in the present work is seven times higher than the previously reported CNPs.Optimized CNPs were characterized by different techniques.Finally,the effect of the mass of CNPs on the removal efficiency was studied as well.
基金supported by National Natural Science Foundation of China (51074189,50823006)Science and Technology Planning Project Founda-tion of Hunan Province,China (2010FJ2006)+1 种基金Research Foundation for the Doctoral Program of Higher Education of China (20100162110001)the National Science & Technology Special Foundation of China (2011BAE09B02,2012ZX04003021)
文摘The as-sintered sinter skin and the polished section of WC-11Co-0.4Cr 3 C 2-0.3VC-0.2RE（RE=mischmetal with La/Ce ratio of 0.65） alloy were analyzed.It was shown that the microstructures on the skin and in the inner part of the alloy were all characterized with a WC＋β＋M structure,where β was a cobalt-based binder phase and M represented a RE-containing phase.There existed an inward diffusion of S atoms,which caught and fixed the Ce atoms in the alloy and an outward diffusion of La atoms during the sintering process.Consequently,the M phase was characterized with the decreased La/Ce ratio（0.59） in the inner part and the increased La/Ce ratio（1.01） on the skin.The M phase on the skin was characterized with a γ-Ce 2 S 3 type structure.To suppress the long range migration of rare earth to the skin,S in the sintering atmosphere had to be eliminated.
