摘要
首次采用溶胶-凝胶法与共沸蒸馏法耦合技术制备了纳米Cr2O3粉体,并运用BET、TEM、XRD、FT-IR、XPS及H2-TPR对其进行表征,同时采用CO2氧化乙烷脱氢制乙烯反应作为探针反应,考察了纳米Cr2O3的催化性能。首次发现纳米Cr2O3的FT-IR谱出现了蓝移现象,并且630cm-1附近的伸缩振动峰强度增强。初步探讨了纳米氧化物的IR蓝移和红移的原因,指出晶型是影响纳米氧化物红外光谱特征的重要因素。实验结果表明纳米Cr2O3上乙烷和CO2转化率均明显高于常规Cr2O3催化剂;在700℃下,乙烷转化率高达77.1%,而乙烯产率达到了58.98%。
In this paper, the nanosized Cr2O3 were prepared by Sol-Gel method coupling with azeotropic distillation method. The obtained nano-powders were characterized by BET, XRD, TEM, Fr-IR, XPS and H-2-TPR techniques. Fr-IR patterns revealed that the infrared absorption peaks of Cr-O bond in Cr2O3 nano-powders blue shift and the intensity of the absorption of Cr-O bond (651.8cm(-1)) increases. The mechanism of red shift and blue shift in nano-powders of oxides was discussed, and it was concluded that the crystal structure of nano-powders of oxides influences their infrared spectra. The catalytic performance of nano-Cr2O3 catalyst for oxidative dehydrogenation of ethane with CO2 was compared with that of normal Cr2O3 catalyst. The nano-Cr2O3 catalyst exhibits much higher ethane conversion and higher ethylene yield than those of normal Cr2O3 catalyst. At 973K, nano-Cr2O3 catalyst shows 77.1% ethane conversion and 58.98% ethylene yield for the oxidative dehydrogenation of ethane with carbon dioxide to ethylene.
出处
《无机化学学报》
SCIE
CAS
CSCD
北大核心
2003年第8期825-830,共6页
Chinese Journal of Inorganic Chemistry
基金
国家863计划资助项目(No.2001AA07010)。