Ce1–xLaxOy solid solution prepared from mixed rare earth chloride for soot oxidation
来源期刊:Journal of Rare Earths2016年第6期
论文作者:韩雪 王亚飞 郝红蕊 郭荣贵 胡运生 蒋文全
文章页码:590 - 596
摘 要:Ce1–xLaxOy solid solution was simply prepared using mixed rare earth chloride(RECl3·x H2O, RE=Ce, La>99%, containing unseparated Ce and La from rare earth metallurgical industry) as precursor by ultrasonic-assisted co-precipitation method with different ultrasonic frequencies(CLf, f=200, 400, 600, 800, 1000 Hz). A compared Ce1–xLaxOy solid solution(CL*) was also prepared by the same mothod with 10% less precipitant. X-ray diffraction results confirmed the formation of Ce1–xLaxOy solid solution, and the crystal structures of these catalysts were not very sensitive to ultrasonic frequency and precipitant amount. However, both of the factors had obvious effect on morphology and surface area of CL, and precipitant amount seem to play a more crucial role than ultrasonic frequency for Ce1–xLaxOy solid solution preparation. When soot and catalyst were tight contacted, the peak temperature(Tpeak) of soot oxidation and oxygen reducing temperature for CLf catalysts decreased linearly with increasing surface area. Under loose contact condition, the Tpeak had obvious negative correlation with H2 consumption. It was inferred that good reducibility of the Ce1–xLaxOy solid solution favored the soot oxidation reaction. The Ce1–xLaxOy solid solution prepared from unseparated rare earth chloride showed a good soot oxidaiton activity. Controlling the preparation conditions to prepare a CL catalyst would high surface area will enhance its reducibility and activity.
韩雪1,王亚飞2,郝红蕊1,郭荣贵1,胡运生1,蒋文全1
1. Institute of Rare Earth Metallurgical Materials General Research Institute for Nonferrous Metals2. School of Mechanical Engi- neering Beijing Institute of Petrochemical Technology
摘 要:Ce1–xLaxOy solid solution was simply prepared using mixed rare earth chloride(RECl3·x H2O, RE=Ce, La>99%, containing unseparated Ce and La from rare earth metallurgical industry) as precursor by ultrasonic-assisted co-precipitation method with different ultrasonic frequencies(CLf, f=200, 400, 600, 800, 1000 Hz). A compared Ce1–xLaxOy solid solution(CL*) was also prepared by the same mothod with 10% less precipitant. X-ray diffraction results confirmed the formation of Ce1–xLaxOy solid solution, and the crystal structures of these catalysts were not very sensitive to ultrasonic frequency and precipitant amount. However, both of the factors had obvious effect on morphology and surface area of CL, and precipitant amount seem to play a more crucial role than ultrasonic frequency for Ce1–xLaxOy solid solution preparation. When soot and catalyst were tight contacted, the peak temperature(Tpeak) of soot oxidation and oxygen reducing temperature for CLf catalysts decreased linearly with increasing surface area. Under loose contact condition, the Tpeak had obvious negative correlation with H2 consumption. It was inferred that good reducibility of the Ce1–xLaxOy solid solution favored the soot oxidation reaction. The Ce1–xLaxOy solid solution prepared from unseparated rare earth chloride showed a good soot oxidaiton activity. Controlling the preparation conditions to prepare a CL catalyst would high surface area will enhance its reducibility and activity.
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