摘要
制备并表征了KVO_3、K_4V_2O_7和熔盐KVO_3+KCl、K_4V_2O_7+KCl催化剂.用固定床反应器通过程序升温氧化法(TPO)研究了催化剂在紧密接触和松散接触条件下对柴油发动机排气微粒中碳烟氧化的催化活性,考察了催化剂的热稳定性,并用泡沫陶瓷作为过滤材料研究了催化剂的性能.结果表明:钒酸盐催化剂KV0_3、K_4V_2O_7、KVO_3+KCl和K_4V_2O_7+KCl对柴油机排气中碳烟微粒的燃烧具有较高的催化活性和热稳定性.熔盐催化KVO_3+KCl和K_4V_2O_7+KCl的流动性增加了与碳烟的接触,使其具有较高的催化能力、γ-Al_2O_3能防止负载于其上的催化剂因吸潮而产生的团聚,但是其稀释作用使催化剂的性能降低.与碳烟的接触方式对催化剂的性能有很大影响,紧密接触方式使催化剂与碳烟颗粒混合均匀,增加了催化剂与碳烟颗粒的接触机会.
The catalysts of KVO3, K4V3O7, KVO3+KCI and K4V2O7+KCI were prepared and characterized. Their catalytic activity was investigated by a fixed-bed reactor for the soot obtained from the diesel emissions under the tight and loose contact mode. The thermal stability of catalysts and catalytic performance of catalysts supported on foam ceramic were also studied. The results show that the catalysts of KVO3, K4V2O7, KVO3+KCI and K4V2O7+KCI have high thermal stability and catalytic activity for the soot. The molten salt catalysts of KVO3+KCI and K3\/2O7+KCI have higher activity than that of KVO3, K4V2O7 because their mobility increases the contact chance of catalysts and soot. The contact mode between catalyst and soot is an important factor that influences the catalytic performance of catalysts. The catalyst and soot are mixed evenly under the mode of tight contact, which increases the contact chance of catalyst and soot.
出处
《材料研究学报》
EI
CAS
CSCD
北大核心
2004年第2期205-211,共7页
Chinese Journal of Materials Research
基金
国家科技攻关计划2002BA314B05
关键词
无机非金属材料
钒酸盐
催化
碳烟
Catalysis
Catalyst activity
Ceramic foams
Diesel engines
Fluidity
Nonmetallic materials
Oxidation
Soot
