ENHANCED SULFUR OXIDE/NITROGEN OXIDE TRAP FOR PROTECTING NITROGEN OXIDE STORAGE-REDUCTION CATALYST FROM SULFUR POISONING

摘要

PROBLEM TO BE SOLVED: To develop an enhanced exhaust gas purification system for a combustion source, including a hydrogen generation system, a sulfur oxide trap, and nitrogen storage-reduction (NSR) catalyst trap and an enhanced exhaust gas purification method.;SOLUTION: A water-gas shift catalyst is arranged between a sulfur oxide trap and an NSR catalyst trap and a purification catalyst is arranged downstream of the NSR catalyst trap. Furthermore, a sulfur trap regenerable at an intermediate temperature rather than a high temperature by a rich pulse is arranged. Sulfur emitted from the sulfur trap is passed through the nitrogen oxide trap without or with hardly poisoning NO_X occlusion and reduction points. This is appropriate for substantially improving a life and a performance of the NSR catalyst trap, satisfying a future exhaust standard, and for use in an internal combustion engine operating at a lean gas-fuel ratio in almost all operation periods.;COPYRIGHT: (C)2014,JPO&INPIT