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公开(公告)号:US20190083967A1
公开(公告)日:2019-03-21
申请号:US16142451
申请日:2018-09-26
Applicant: BASF Corporation
Inventor: Xiaofan Yang , Weiyong Tang , Ze Zhang
Abstract: The present invention provides methods for low temperature desulfating sulfur-poisoned SCR catalysts, and emission control systems adapted to apply such desulfating methods, in order to regenerate catalytic NOx conversion activity. The methods are adapted for treating an SCR catalyst to desorb sulfur from the surface of the SCR catalyst and increase NOx conversion activity of the SCR catalyst, the treating step including treating the SCR catalyst with a gaseous stream comprising a reductant for a first treatment time period and at a first treatment temperature, wherein the first treatment temperature is about 350° C. or less, followed by a second treatment time period and a second treatment temperature higher than the first treatment temperature, wherein the molar ratio of reductant to NOx during the treating step is about 1.05:1 or higher.
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公开(公告)号:US11097264B2
公开(公告)日:2021-08-24
申请号:US16142451
申请日:2018-09-26
Applicant: BASF Corporation
Inventor: Xiaofan Yang , Weiyong Tang , Ze Zhang
IPC: B01J38/08 , B01J29/90 , B01J29/76 , B01D53/94 , B01D53/96 , F01N3/20 , F01N3/28 , B01J38/02 , B01J29/072 , B01J29/72 , B01J29/70 , B01J29/06 , B01J37/02 , F01N3/035 , F01N3/10
Abstract: The present invention provides methods for low temperature desulfating sulfur-poisoned SCR catalysts, and emission control systems adapted to apply such desulfating methods, in order to regenerate catalytic NOx conversion activity. The methods are adapted for treating an SCR catalyst to desorb sulfur from the surface of the SCR catalyst and increase NOx conversion activity of the SCR catalyst, the treating step including treating the SCR catalyst with a gaseous stream comprising a reductant for a first treatment time period and at a first treatment temperature, wherein the first treatment temperature is about 350° C. or less, followed by a second treatment time period and a second treatment temperature higher than the first treatment temperature, wherein the molar ratio of reductant to NOx during the treating step is about 1.05:1 or higher.
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