Platinum/cerium-zirconium-sulfate（Pt/Ce-Zr-SO_4^（2-）） catalysts were prepared by wetness impregnation.Catalytic activities were evaluated from the combustion of propene and CO.Sulfate（SO_4^（2-））addition improv...Platinum/cerium-zirconium-sulfate（Pt/Ce-Zr-SO_4^（2-）） catalysts were prepared by wetness impregnation.Catalytic activities were evaluated from the combustion of propene and CO.Sulfate（SO_4^（2-））addition improved the catalytic activity significantly.When using Pt/Ce-Zr-SO_4^（2-） with 10 wt%SO_4^（2-）,the temperature for 90%conversion of propene and CO decreased by 75℃ compared with Pt/Ce-Zr.The conversion exceeded 95%at 240℃ even after 0.02%sulfur dioxide poisoning for 20 h.Temperature-programmed desorption of CO and X-ray photoelectron spectroscopy analyses revealed an improvement in Pt dispersion onto the Ce-Zr-SO_4^（2-） support,and the increased number of Pt particles built up more Pt^（-）-（SO_4^（2-））^（-） couples,which resulted in excellent activity.The increased total acidity and new Bronsted acid sites on the surface provided the Pt/Ce-Zr-SO_4^（2-） with good sulfur resistance.展开更多
The V-K catalysts were produced on porous α-alumina substrate by a solution impregnation route and the compositions and catalytic activities for soot oxidation were studied by XRD, TG/DTG, DSC and TPR. According to t...The V-K catalysts were produced on porous α-alumina substrate by a solution impregnation route and the compositions and catalytic activities for soot oxidation were studied by XRD, TG/DTG, DSC and TPR. According to the catalytic activity studies, the catalytic activity of the crystalline phases is in the order： KNO3＋KVO3〉K3V5O14＋KVO3. The appearance of excessive KHCO3 phase will lead to the deterioration of catalytic activity when the catalysts contain higher KNO3 content. It is also found that when the K∶V molar ratio is higher than 1∶1, the prepared catalysts show a strong CO2 absorption characteristic and this behavior will become gradually significant with the increasing of K∶V molar ratio. Considerable amount of absorbed CO2 are strongly bonded to the crystal lattice with onset desorption temperature of 200 ℃.展开更多
Diesel soot is related to incomplete fuel oxidation, and possesses the well-known mutagenic effects on human health.Diesel soot was collected from diesel engines and oxidized in laboratorial micro reactor by several p...Diesel soot is related to incomplete fuel oxidation, and possesses the well-known mutagenic effects on human health.Diesel soot was collected from diesel engines and oxidized in laboratorial micro reactor by several prepared rare earth-based catalysts with or without different harmful monoxide gases such as NO, and activities of several rare earth catalysts were studied.The results indicate that soot can be more easily oxidized with monoxide gases.展开更多
Diesel oxide catalysts and soot combustion catalysts were reported in this paper.The former was manufactured in mass last year, and enhanced performance is under development now.The later is screened out and further r...Diesel oxide catalysts and soot combustion catalysts were reported in this paper.The former was manufactured in mass last year, and enhanced performance is under development now.The later is screened out and further research is under way.The best soot combustion catalyst could ignite soot combustion even at 350 ℃, which is within the range of temperatures reached in diesel exhaust, and shows the catalytic combustion velocity nearly one time faster compared with non-catalytic combustion of soot, which is of benefit to rapid regeneration of diesel particulate filter, thus it might be an excellent practicable catalyst.展开更多
An ultrasound-assisted heterogeneous catalytic oxidation process was applied to eliminate sulfur from commercial diesel fuel oil.The studied variables were catalyst concentration,type of catalyst(homogeneous or hetero...An ultrasound-assisted heterogeneous catalytic oxidation process was applied to eliminate sulfur from commercial diesel fuel oil.The studied variables were catalyst concentration,type of catalyst(homogeneous or heterogeneous),oxidizing agent concentration,and the application of ultrasound energy.Supported catalysts were prepared by impregnation of coal fly ash with an iron(Ⅱ)sulfate aqueous solution using ultrasound energy.After drying,the catalyst was calcined at 500℃for 4 h.The oxidizing agent was hydrogen peroxide.Ultrasound energy was applied with a frequency of 47 kHz and an intensity of 147 W.Ethanol was employed for extracting the oxidized compounds from the hydrocarbon mixture.Coal fly ash and ethanol were used with the purpose of applying low-cost raw materials in chemical processes.It was found that under the studied conditions,increasing oxidizing agent concentration and the application of ultrasound energy can enhance the sulfur removal from commercial diesel fuel oil.Catalyst concentration did not play a significant role in the process.Similar results were obtained using homogeneous or heterogeneous catalyst,which is important since the heterogeneous catalyst could be recovered,reactivated,and used in many cycles.展开更多
In order to reduce oxides of nitrogen （NOx） emanated from a diesel engine, a comprehensive urea selective catalyst reduction （SCR） DeNOx catalyst was modeled in which numerical simulations were used as a complemen...In order to reduce oxides of nitrogen （NOx） emanated from a diesel engine, a comprehensive urea selective catalyst reduction （SCR） DeNOx catalyst was modeled in which numerical simulations were used as a complementary tool for the experimental investigations to make the design decisions, and hence shorten the de- velopment process. In this approach, relevant conversion reactions were studied in 1D model, and the parame- ters obtained in this way were transferred to 3D simulations. According to the results of the study, the conver- sion of NO and NO2 increased with the increase in monolith solid temperature. With the increase in the ratio of NO2/NOx the conversion of NO, NO2 and NOx increased resulting in maximum reduction of NOxat the ratio of 1; beyond this ratio, the conversion of NO2 and NOx decreased; however, NO continued to be converted till the ratio was 1.8. The conversion of NOx decreased with the increase in space velocity.展开更多
基金supported by the National Natural Science Foundation of China(21506194,21676255)the Provincial Natural Science Foundation of Zhejiang Province(LY16B070011)the Commission of Science and Technology of Zhejiang Province(2017C33106,2017C03007)~~
文摘Platinum/cerium-zirconium-sulfate（Pt/Ce-Zr-SO_4^（2-）） catalysts were prepared by wetness impregnation.Catalytic activities were evaluated from the combustion of propene and CO.Sulfate（SO_4^（2-））addition improved the catalytic activity significantly.When using Pt/Ce-Zr-SO_4^（2-） with 10 wt%SO_4^（2-）,the temperature for 90%conversion of propene and CO decreased by 75℃ compared with Pt/Ce-Zr.The conversion exceeded 95%at 240℃ even after 0.02%sulfur dioxide poisoning for 20 h.Temperature-programmed desorption of CO and X-ray photoelectron spectroscopy analyses revealed an improvement in Pt dispersion onto the Ce-Zr-SO_4^（2-） support,and the increased number of Pt particles built up more Pt^（-）-（SO_4^（2-））^（-） couples,which resulted in excellent activity.The increased total acidity and new Bronsted acid sites on the surface provided the Pt/Ce-Zr-SO_4^（2-） with good sulfur resistance.
基金Funded by the Foundation for Scientific Research Encouragement to Middle-aged and Young Scientists of Shandong Province (No. 2007BS04003)
文摘The V-K catalysts were produced on porous α-alumina substrate by a solution impregnation route and the compositions and catalytic activities for soot oxidation were studied by XRD, TG/DTG, DSC and TPR. According to the catalytic activity studies, the catalytic activity of the crystalline phases is in the order： KNO3＋KVO3〉K3V5O14＋KVO3. The appearance of excessive KHCO3 phase will lead to the deterioration of catalytic activity when the catalysts contain higher KNO3 content. It is also found that when the K∶V molar ratio is higher than 1∶1, the prepared catalysts show a strong CO2 absorption characteristic and this behavior will become gradually significant with the increasing of K∶V molar ratio. Considerable amount of absorbed CO2 are strongly bonded to the crystal lattice with onset desorption temperature of 200 ℃.
文摘Diesel soot is related to incomplete fuel oxidation, and possesses the well-known mutagenic effects on human health.Diesel soot was collected from diesel engines and oxidized in laboratorial micro reactor by several prepared rare earth-based catalysts with or without different harmful monoxide gases such as NO, and activities of several rare earth catalysts were studied.The results indicate that soot can be more easily oxidized with monoxide gases.
文摘Diesel oxide catalysts and soot combustion catalysts were reported in this paper.The former was manufactured in mass last year, and enhanced performance is under development now.The later is screened out and further research is under way.The best soot combustion catalyst could ignite soot combustion even at 350 ℃, which is within the range of temperatures reached in diesel exhaust, and shows the catalytic combustion velocity nearly one time faster compared with non-catalytic combustion of soot, which is of benefit to rapid regeneration of diesel particulate filter, thus it might be an excellent practicable catalyst.
文摘An ultrasound-assisted heterogeneous catalytic oxidation process was applied to eliminate sulfur from commercial diesel fuel oil.The studied variables were catalyst concentration,type of catalyst(homogeneous or heterogeneous),oxidizing agent concentration,and the application of ultrasound energy.Supported catalysts were prepared by impregnation of coal fly ash with an iron(Ⅱ)sulfate aqueous solution using ultrasound energy.After drying,the catalyst was calcined at 500℃for 4 h.The oxidizing agent was hydrogen peroxide.Ultrasound energy was applied with a frequency of 47 kHz and an intensity of 147 W.Ethanol was employed for extracting the oxidized compounds from the hydrocarbon mixture.Coal fly ash and ethanol were used with the purpose of applying low-cost raw materials in chemical processes.It was found that under the studied conditions,increasing oxidizing agent concentration and the application of ultrasound energy can enhance the sulfur removal from commercial diesel fuel oil.Catalyst concentration did not play a significant role in the process.Similar results were obtained using homogeneous or heterogeneous catalyst,which is important since the heterogeneous catalyst could be recovered,reactivated,and used in many cycles.
基金Sponsored by Postdoctoral Science Foundation of China(2007042031)
文摘In order to reduce oxides of nitrogen （NOx） emanated from a diesel engine, a comprehensive urea selective catalyst reduction （SCR） DeNOx catalyst was modeled in which numerical simulations were used as a complementary tool for the experimental investigations to make the design decisions, and hence shorten the de- velopment process. In this approach, relevant conversion reactions were studied in 1D model, and the parame- ters obtained in this way were transferred to 3D simulations. According to the results of the study, the conver- sion of NO and NO2 increased with the increase in monolith solid temperature. With the increase in the ratio of NO2/NOx the conversion of NO, NO2 and NOx increased resulting in maximum reduction of NOxat the ratio of 1; beyond this ratio, the conversion of NO2 and NOx decreased; however, NO continued to be converted till the ratio was 1.8. The conversion of NOx decreased with the increase in space velocity.
