V_mTi和K_nV_(0.04)Ti担载氧化物催化剂的表征与催化燃烧柴油炭黑的性能  

Characterization of V_mTi and K_nV_(0.04)Ti Catalysts Supported by Oxide and Their Catalytic Performances for Diesel Soot Combustion

作　　者：刘坚[1] 赵震[1] 徐春明[1] 

机构地区：[1]石油大学重质油国家重点实验室,北京102249

出　　处：《高等学校化学学报》2005年第7期1290-1293,M006,共5页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:20473053);教育部留学归国人员科学研究及实验室建设重点基金资助

摘　　要：用FT IR和UV-V is研究了2个系列不同V和K负载量的VOx/T iO2和K-VOx/T iO2催化剂结构的变化;并使用程序升温氧化反应技术对这两种催化剂催化柴油炭黑燃烧活性进行了考察.结果表明,当VOx/T iO2催化剂中n(V)∶n(T i)=0.04时,催化剂活性最好(tm=389℃).添加K能显著改善VOx/T iO2催化剂活性,n(K)∶n(V)∶n(T i)=0.04∶0.04∶1时,炭黑燃烧的反应温度最低(tm=343℃).FT IR和UV-V is结果表明,当VOx/T iO2催化剂n(V)∶n(T i)>0.04∶1时,催化剂表面有V2O5形成,由于V2O5氧化能力较弱,因而催化剂的活性反而降低.而当K-VOx/T iO2催化剂中n(K)∶n(V)达到1∶1时,由于形成的KVO3物种与T iO2载体有很好的协同作用,所以催化剂活性最好.Two systems of V_mTi and K_nV_(0.04)Ti catalysts were prepared by incipient-wet impregnation method and their catalytic performances for diesel soot combustion were investigated by using temperature-programmed oxidation(TPO) reaction. The results show that the V_(0.04)Ti catalyst has a good activity for diesel soot combustion(t_m=389 ℃). The addition of potassium to VO_x/ TiO_2 catalysts can apparently improve their catalytic activities for soot oxdation. And when n(K)∶n(V)∶n(Ti)=(0-^04∶0-^04∶1,) the catalysis activity is the best, and the temperature of soot combustion reaction is the lowest reaction temperature(t_m=343 ℃). The structural characterization results by FTIR and UV-Vis reveal that V_2O_5 formed on the surfaces of the V_mTi catalysts when m exceeded 0-^04. The (K_(0.04)V_(0.04)Ti) catalyst has a highest catalytic activity. It is due to the formation of KVO_3 which has a good synergetic effect with TiO_2 support in the catalyst.

关 键 词：催化剂 炭黑 钒氧化物 二氧化钛 催化燃烧 

分 类 号：O643[理学—物理化学]