| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a selective catalytic reduction (SCR) catalyst, exhaust gas cleaning filter, and exhaust gas cleaning apparatus, capable of improving a NOx removing ratio in a low-temperature region and suppressing degradation of the NOx removing ratio even when exposure to a hot hydrothermal atmosphere is continued for a long time. <P>SOLUTION: A SCR catalyst coated on DPF4 is a substance obtained by carrying a third component on a carrier composed of a first component and a second component. The first component is composed of at least either one of Sn and Sn compounds such as SnO<SB POS="POST">2</SB>. The second component is composed of at least any one of Ce and Ce compounds such as CeO<SB POS="POST">2</SB>, Fe and Fe compounds such as Fe<SB POS="POST">2</SB>O<SB POS="POST">3</SB>and Cu, and Cu compounds such as CuO. The third component is composed of at least any one of W, and W compounds such as WO<SB POS="POST">3</SB>, Mo and Mo compound such as MoO<SB POS="POST">3</SB>, V and V compounds such as V<SB POS="POST">2</SB>O<SB POS="POST">5</SB>, Nb and Nb compounds such as Nb<SB POS="POST">2</SB>O<SB POS="POST">5</SB>and Ta and Ta compounds such as Ta<SB POS="POST">2</SB>O<SB POS="POST">5</SB>. <P>COPYRIGHT: (C)2012,JPO&INPIT |
