In this work, the removal of thiophene from simulated oil has been studied by using the adsorption, extraction and oxidation/adsorption methods, respectively. In the adsorptive desulfurization process, different comme...In this work, the removal of thiophene from simulated oil has been studied by using the adsorption, extraction and oxidation/adsorption methods, respectively. In the adsorptive desulfurization process, different commercial adsorbents were used to eliminate thiophene at ambient pressure and mild temperature, and the results showed that carbon powder had the best adsorption ability. In the extractive desulfurization process, the best desulfurization result was obtained when DMF is used. In the oxidative/adsorptive desulfurization procedure using synthesized potassium ferrate as the oxidant and phosphomolybdic acid solution as the catalyst, thiophene was oxidized and removed from hydrocarbons in combination with active carbon adsorption, and the residual sulfur content of simulated oil could be reduced to 15.3mg/L from the original level of 200mg/L, with the desulfurization rate reaching 92.3%.展开更多
The effects of olefins were quantified by measuring the decreased amount of thiophenes removed by modified zeolites with an increasing olefin concentration in model fuels (300 ppm) via fixed-bed adsorption technique...The effects of olefins were quantified by measuring the decreased amount of thiophenes removed by modified zeolites with an increasing olefin concentration in model fuels (300 ppm) via fixed-bed adsorption technique at room temperature and atmosphere pressure. The influence of olefins on adsorptive desulfurization of model fuel had been investigated by FT-IR techniques, which revealed that the protons in the zeolites were the sites responsible for the adsorption of olefins. On the CeY zeolite, in the presence of strong hydroxyl species in the zeolites, the adsorbed olefin compounds can attach to the protons molecularly via electrophilic interaction and undergo the opening of the C=C bonds depending on the acidity of the zeolites. The reduced desulfurization performance of CeY zeolite was attributed to the direct occupation of the absorbent's active sites by olefins. In contrast to the CeY zeolite, the NiY zeolites were unable to react directly with pure olefins. However the sulfur compounds and olefins adsorbed on the protons may subsequently undergo olefin alkylation reactions, which can block the zeolite pores and then prevent sulfide molecules from having access to super-cages to contact with the metal cations. This work demonstrates also that the NiY zeolites exhibit excellent performance for selective adsorption desulfurization of model fuel containing olefin compounds.展开更多
基金financially supported by the Science and Technology Program of the Department of Education,Heilongjiang Province(11531012)
文摘In this work, the removal of thiophene from simulated oil has been studied by using the adsorption, extraction and oxidation/adsorption methods, respectively. In the adsorptive desulfurization process, different commercial adsorbents were used to eliminate thiophene at ambient pressure and mild temperature, and the results showed that carbon powder had the best adsorption ability. In the extractive desulfurization process, the best desulfurization result was obtained when DMF is used. In the oxidative/adsorptive desulfurization procedure using synthesized potassium ferrate as the oxidant and phosphomolybdic acid solution as the catalyst, thiophene was oxidized and removed from hydrocarbons in combination with active carbon adsorption, and the residual sulfur content of simulated oil could be reduced to 15.3mg/L from the original level of 200mg/L, with the desulfurization rate reaching 92.3%.
基金supported by the National Natural Science Foundation of China(No. 20476042 and No.20776064)the Ministry of Science and Technology of the People's Republic of China under the National Basic Research Program of China(973 Program) (2007CB216403)
文摘The effects of olefins were quantified by measuring the decreased amount of thiophenes removed by modified zeolites with an increasing olefin concentration in model fuels (300 ppm) via fixed-bed adsorption technique at room temperature and atmosphere pressure. The influence of olefins on adsorptive desulfurization of model fuel had been investigated by FT-IR techniques, which revealed that the protons in the zeolites were the sites responsible for the adsorption of olefins. On the CeY zeolite, in the presence of strong hydroxyl species in the zeolites, the adsorbed olefin compounds can attach to the protons molecularly via electrophilic interaction and undergo the opening of the C=C bonds depending on the acidity of the zeolites. The reduced desulfurization performance of CeY zeolite was attributed to the direct occupation of the absorbent's active sites by olefins. In contrast to the CeY zeolite, the NiY zeolites were unable to react directly with pure olefins. However the sulfur compounds and olefins adsorbed on the protons may subsequently undergo olefin alkylation reactions, which can block the zeolite pores and then prevent sulfide molecules from having access to super-cages to contact with the metal cations. This work demonstrates also that the NiY zeolites exhibit excellent performance for selective adsorption desulfurization of model fuel containing olefin compounds.