One of the potential ways to solve the problem of diesel particulate emission from both stationary and mobile sources is the use of traps carrying a suitable catalyst for promoting particulate combustion as soon as it is filtered. A Cu-K-V based catalyst, considered among the most promising in the literature, the KVO3+CsCl and the K0.7Cu0.3VO3+KCl catalysts were prepared and investigated. Their performance was compared to a reference V2O5 catalyst. The superior performance of the Cu-K-V catalyst is based on the grounds of both microreactor (temperature programmed combustion) and catalytic trap tests. Based on experimental data and modelling calculations, this paper elucidates how the mobility of catalyst components is the main reason for such an outcome performance and is a prerequisite to achieve an activity sufficient for trap self-regeneration.