摘要
为了考察搅拌速率在Pd/Al2O3催化剂制备过程中的作用,通过对不同搅拌速率制备的Pd/Al2O3催化剂进行XRD、H2-TPR和XPS表征及CH4催化燃烧活性测试,研究搅拌速率对Pd/Al2O3催化剂活性的影响。结果表明,低搅拌速率[（200-300）r·min^-1]条件制备的催化剂,Pd O粒径较大,Pd分散度高,表面Pd与Pd O物质的量比=0.55-0.56,催化剂的CH4催化反应活化能与无搅拌时相比降低,在200 r·min-1达到最低;随着搅拌速率增加,高搅拌速率[（400-600）r·min^-1]抑制了Pd O晶粒的生长,导致Pd O粒径变小,Pd分散度降低,并使表面Pd O含量增大,Pd与Pd O物质的量比=0.41-0.52,提高了CH4催化燃烧反应的活化能。
The influence of stirring speed during the preparation of Pd / Al2 O3 catalysts on the catalytic activities of the catalysts were investigated by XRD,H2-TPR,XPS and CH4 catalytic combustion activity test. The results showed that Pd/ Al2 O3 catalyst prepared under low stirring speed[（200 -300）r·min^ - 1 ] exhibited higher activity than the catalyst prepared under stirring speed（0 r·min^ - 1 ）because of the larger PdO particle size,higer Pd dispersion and Pd / PdO molar ratio（0. 55 - 0. 56）. The optimum activity was achieved over Pd / Al2 O3 catalyst prepared under stirring speed 200 r · min ^- 1 . With the increase of stirring speed,Pd / Al2 O3 catalyst prepared under high stirring speed[（400 - 600）r·min ^- 1 ] performed lower activity than Pd / Al2 O3 catalyst prepared under low stirring speed due to its smaller PdO particle size,lower Pd dispersion and Pd / PdO molar ratio（0. 41 - 0. 52）.
出处
《工业催化》
CAS
2015年第1期45-49,共5页
Industrial Catalysis
