Patent ID: 11933725
Assignee: NATIONAL UNIVERSITY CORPORATION OKAYAMA UNIVERSITY
Field: Measurement (Instruments)
Classification: CPC G  B | IPC B  G

Claim 6:
7. A method for recovering an exhaust gas purifying catalyst that purifies exhaust gas emitted by an internal combustion engine in which gasoline is combusted, wherein the method comprises:
(A) estimating the sulfur component concentration in the gasoline by the method according to claim 1,
(B) estimating an estimated accumulated amount of sulfur oxides in the exhaust gas emitted by the internal combustion engine, based on the sulfur component concentration, and
(C) recovering the exhaust gas purifying catalyst from sulfur oxide-derived poisons when the estimated accumulated amount of discharged sulfur oxides is above a threshold value,
wherein a reduction in exhaust gas purification efficiency of the exhaust gas purifying catalyst with respect to the estimated accumulated amount of sulfur oxides is measured first, and the threshold value is established as the estimated accumulated amount of sulfur oxides at the point where the exhaust gas purification efficiency has fallen below a predetermined level.