CU-CHA ZEOLITE FOR NH3-SCR CATALYST TO BE USED IN DIESEL AUTOMOTIVE EXHAUST GAS PURIFICATION CATALYST SYSTEM, AND DIESEL AUTOMOTIVE EXHAUST GAS PURIFICATION CATALYST SYSTEM COMPRISING SAME

摘要

A Cu-CHA zeolite having a silica/alumina ratio (SAR) by mol of less than 15, wherein, in an FT-IR spectrum thereof, when a peak P1 at the wave number of 3,745 cm-1 has a peak area AP1 and a peak P0 at the wave number of 1,975 cm-1 has a peak area AP0, then the peak area ratio (AP1/AP0) is 0.070 or less. This Cu-CHA zeolite is for an NH3-SCR catalyst that is to be used in a diesel automotive exhaust gas purification catalyst system.