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
采用高硫柴油、国Ⅲ、国Ⅳ和国Ⅴ4种不同硫含量的基准燃油,在发动机台架上进行了加装DOC+POC后处理装置的国Ⅳ柴油机的ESC 13工况测试,并用AVL AMA i60气体分析仪对CO,HC,NOx和PM排放进行测量。研究了不同基准燃油对加装DOC+POC后处理...采用高硫柴油、国Ⅲ、国Ⅳ和国Ⅴ4种不同硫含量的基准燃油,在发动机台架上进行了加装DOC+POC后处理装置的国Ⅳ柴油机的ESC 13工况测试,并用AVL AMA i60气体分析仪对CO,HC,NOx和PM排放进行测量。研究了不同基准燃油对加装DOC+POC后处理装置的国Ⅳ柴油机的排放影响,并与原机作了对比。研究结果表明,CO和HC的转化效率与燃油硫含量有很好的相关性,DOC+POC后处理可有效减小CO和HC的排放,稳态循环下国Ⅴ柴油CO和HC的平均转化效率分别为90.6%和86.6%,且随着燃油中含硫量的降低而增大,特别是在高转速大负荷工况。受燃油硫含量影响,DOC+POC后处理装置对高硫柴油、国Ⅲ、国Ⅳ3种燃油的PM排放降低不起作用,反而会使PM排放增加,然而对国Ⅴ柴油的PM净化率可达81.8%。展开更多
开展DOC和金属滤芯DPF对柴油机排气碳烟石墨化程度和氧化活性影响规律的研究,并分析了石墨化程度与氧化活性的相关性。结果表明:柴油机排气碳烟中2种方法所获得石墨化程度(AG/AD1和R值)及氧化反应表观活化能(Ea)分别处于0.205~0.293、0....开展DOC和金属滤芯DPF对柴油机排气碳烟石墨化程度和氧化活性影响规律的研究,并分析了石墨化程度与氧化活性的相关性。结果表明:柴油机排气碳烟中2种方法所获得石墨化程度(AG/AD1和R值)及氧化反应表观活化能(Ea)分别处于0.205~0.293、0.094~0.136及138.9~168.1 k J/mol之间;原机排放碳烟的AG/AD1、R值和Ea均随转速的升高而下降,随负荷的升高而提高;DOC处理后碳烟的AG/AD1、R值和Ea显著提高,且涨幅也基本上随转速的升高而下降,随负荷的升高而提高;多数工况下,金属滤芯DPF对AG/AD1、R值及Ea的影响极小;DOC处理前、后碳烟中AG/AD1或R值与Ea有一定相关性,且Ea对AG/AD1更敏感;DOC能够改善Ea与AG/AD1的相关性,但对Ea与R值的相关性影响不大。展开更多
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.
文摘采用高硫柴油、国Ⅲ、国Ⅳ和国Ⅴ4种不同硫含量的基准燃油,在发动机台架上进行了加装DOC+POC后处理装置的国Ⅳ柴油机的ESC 13工况测试,并用AVL AMA i60气体分析仪对CO,HC,NOx和PM排放进行测量。研究了不同基准燃油对加装DOC+POC后处理装置的国Ⅳ柴油机的排放影响,并与原机作了对比。研究结果表明,CO和HC的转化效率与燃油硫含量有很好的相关性,DOC+POC后处理可有效减小CO和HC的排放,稳态循环下国Ⅴ柴油CO和HC的平均转化效率分别为90.6%和86.6%,且随着燃油中含硫量的降低而增大,特别是在高转速大负荷工况。受燃油硫含量影响,DOC+POC后处理装置对高硫柴油、国Ⅲ、国Ⅳ3种燃油的PM排放降低不起作用,反而会使PM排放增加,然而对国Ⅴ柴油的PM净化率可达81.8%。
文摘开展DOC和金属滤芯DPF对柴油机排气碳烟石墨化程度和氧化活性影响规律的研究,并分析了石墨化程度与氧化活性的相关性。结果表明:柴油机排气碳烟中2种方法所获得石墨化程度(AG/AD1和R值)及氧化反应表观活化能(Ea)分别处于0.205~0.293、0.094~0.136及138.9~168.1 k J/mol之间;原机排放碳烟的AG/AD1、R值和Ea均随转速的升高而下降,随负荷的升高而提高;DOC处理后碳烟的AG/AD1、R值和Ea显著提高,且涨幅也基本上随转速的升高而下降,随负荷的升高而提高;多数工况下,金属滤芯DPF对AG/AD1、R值及Ea的影响极小;DOC处理前、后碳烟中AG/AD1或R值与Ea有一定相关性,且Ea对AG/AD1更敏感;DOC能够改善Ea与AG/AD1的相关性,但对Ea与R值的相关性影响不大。
