Abstract: An exhaust control system for an internal combustion engine comprises: a trapping capability acquisition part that obtains information regarding a PM trapping capability, based on a detection value of an exhaust sensor provided to detect a predetermined parameter relating to an exhaust gas flowing out of an SCRF; and a NOx reduction capability acquisition part obtains information regarding a NOx reduction capability, based on an amount of NOx in the exhaust gas flowing out of the SCRF. The exhaust control system determines and distinguishes between a trapping abnormal state in which a PM trapping function by the SCRF is failed and a sensor abnormal state in which a detection function of the predetermined parameter by the exhaust sensor is failed, based on the NOx reduction capability obtained by the NOx reduction capability acquisition part, when the trapping capability obtained by the trapping capability acquisition part is in a predetermined low trapping capability state.

Abstract: Embodiments of the present disclosure may improve the accuracy of diagnosis in diagnosing whether an exhaust gas purification system having an SCR filter is faulty. It is determined that the exhaust gas purification system is faulty if the NOx removal rate with the SCR filter calculated using a measurement value of an NOx sensor is lower than or equal to a predetermined criterion removal rate. In the apparatus, a differential pressure change rate defined as the increase in a converted differential pressure value per unit increase in the filter PM deposition amount is calculated. The value of the criterion removal rate is set higher when the differential pressure change rate at the time when the measurement value of the NOx sensor is obtained is lower than a predetermined threshold than when the differential pressure change rate is higher than or equal to the predetermined threshold.

Abstract: An exhaust gas purification catalyst containing a CeO2 particle supported on the surface of an MnO2 particle, wherein the Ce amount relative to the total amount of Mn and Ce (Ce/(Mn+Ce)) in the catalyst is more than 0 mol % and 40 mol % or less; and a method for producing the exhaust gas purification catalyst above, including mixing an aqueous solution containing a manganese ion and a cerium ion in a ratio of more than 0 mol % and 40 mol % or less in terms of the Ce amount relative to the total amount of Mn and Ce (Ce/(Mn+Ce)) and an aqueous solution having dissolved therein a carbonate ion-containing reducing agent, thereby precipitating a particle, and firing the particle, are provided.

Abstract: Embodiments of the present disclosure may estimate the amount of ammonia adsorbed in an SCR catalyst as accurately as possible. The ammonia adsorption amount is calculated by integrating the quantity of ammonia supplied to the SCR filter, the quantity of ammonia consumed in reduction of NOx in the SCR catalyst, and the quantity of ammonia desorbed from the SCR catalyst. In the calculation, a differential pressure change rate defined as the increase in a converted differential pressure value per unit increase in the filter PM deposition amount is referred to. The ammonia desorption quantity is calculated in such a way that the calculated value of the ammonia desorption quantity is made smaller when the differential pressure change rate is smaller than a predetermined threshold than when the differential pressure change rate is equal to or higher than the predetermined threshold.

Abstract: When an integrated value of a determination value correlated with a command value for an amount of supply of a reducing agent at the time of the command value being larger than a command supply amount threshold value reaches an integration threshold value, a determination is made that a diagnosis condition is satisfied, and an abnormality in the supply of the reducing agent is diagnosed based on an integrated value of the command value for the amount of supply of the reducing agent and an integrated value of an estimated value of the amount of supply of the reducing agent, whereas in cases where a period of time in which the diagnosis condition is not satisfied is longer than a time period threshold value, an interval of supply of the reducing agent is extended.

Abstract: An object of the disclosure is to adjust the ammonia adsorption amount in an SCR catalyst supported on an SCR filter as close as possible to a target adsorption amount in an exhaust gas purification system including the SCR filter. In a system according to the disclosure, the quantity of ammonia supplied by an ammonia supplier is made smaller when a differential pressure change rate at the time when ammonia is supplied by the ammonia supplier is lower than a predetermined threshold than when the differential pressure change rate at the time when ammonia is supplied by the ammonia supplier is equal to or higher than the predetermined threshold. Moreover, when the differential pressure change rate is lower than the predetermined threshold, the change in the quantity of ammonia supplied by the ammonia supplier relative to the change in the filter PM deposition amount is kept equal to zero.

Abstract: A diagnostic system for an internal combustion engine is disclosed. The diagnostic system may include an electronic control unit. The electronic control unit may determine whether a predetermined condition is satisfied. The predetermined condition may be a condition under which an amount of particulate matter that separates from a filter is larger than or equal to a predetermined separation amount as a urea water-originated deposit once accumulated in the filter separates in gaseous form. When the electronic control unit determines that the predetermined condition is satisfied, the electronic control unit may not execute a diagnosis of a malfunction in the filter based on a filter differential pressure until a predetermined period elapses from the point in time at which it is determined that the predetermined condition is satisfied.

Abstract: When an integrated value of a determination value correlated with a command value for an amount of supply of a reducing agent at the time of the command value being larger than a command supply amount threshold value reaches an integration threshold value, a determination is made that a diagnosis condition is satisfied, and an abnormality in the supply of the reducing agent is diagnosed based on an integrated value of the command value for the amount of supply of the reducing agent and an integrated value of an estimated value of the amount of supply of the reducing agent, whereas in cases where a period of time in which the diagnosis condition is not satisfied is longer than a time period threshold value, an interval of supply of the reducing agent is extended.

Abstract: An exhaust gas purification catalyst containing a CeO2 particle supported on the surface of an MnO2 particle, wherein the Ce amount relative to the total amount of Mn and Ce (Ce/(Mn+Ce)) in the catalyst is more than 0 mol % and 40 mol % or less; and a method for producing the exhaust gas purification catalyst above, including mixing an aqueous solution containing a manganese ion and a cerium ion in a ratio of more than 0 mol % and 40 mol % or less in terms of the Ce amount relative to the total amount of Mn and Ce (Ce/(Mn+Ce)) and an aqueous solution having dissolved therein a carbonate ion-containing reducing agent, thereby precipitating a particle, and firing the particle, are provided.

Abstract: An additive amount of a reducing agent to a selective reduction-type NOx catalyst is optimized. An ammonia adsorption amount of the selective reduction-type NOx catalyst is estimated based on one or a plurality of prescribed parameters related to the ammonia adsorption amount and a specific ammonia adsorption amount that is an estimated value of the ammonia adsorption amount specified by at least one of a maximum value and a minimum value of an estimated value of the ammonia adsorption amount is estimated based on an error in the prescribed parameter, and when the specific ammonia adsorption amount is outside a target range of the ammonia adsorption amount, addition of an ammonia precursor or ammonia using an adding valve is controlled such that the specific ammonia adsorption amount returns to the target range.

Abstract: An object of the disclosure is to adjust the ammonia adsorption amount in an SCR catalyst supported on an SCR filter as close as possible to a target adsorption amount in an exhaust gas purification system including the SCR filter. In a system according to the disclosure, the quantity of ammonia supplied by an ammonia supplier is made smaller when a differential pressure change rate at the time when ammonia is supplied by the ammonia supplier is lower than a predetermined threshold than when the differential pressure change rate at the time when ammonia is supplied by the ammonia supplier is equal to or higher than the predetermined threshold. Moreover, when the differential pressure change rate is lower than the predetermined threshold, the change in the quantity of ammonia supplied by the ammonia supplier relative to the change in the filter PM deposition amount is kept equal to zero.

Abstract: An object of the invention is to suppress a reduction in accuracy of abnormality diagnosis with an abnormality diagnosis device for an exhaust gas control apparatus that performs the abnormality diagnosis regarding the exhaust gas control apparatus by using the amount of NOx flowing into an SCR catalyst as a parameter.

Abstract: Embodiments of the present disclosure may improve the accuracy of diagnosis in diagnosing whether an exhaust gas purification system having an SCR filter is faulty. It is determined that the exhaust gas purification system is faulty if the NOx removal rate with the SCR filter calculated using a measurement value of an NOx sensor is lower than or equal to a predetermined criterion removal rate. In the apparatus, a differential pressure change rate defined as the increase in a converted differential pressure value per unit increase in the filter PM deposition amount is calculated. The value of the criterion removal rate is set higher when the differential pressure change rate at the time when the measurement value of the NOx sensor is obtained is lower than a predetermined threshold than when the differential pressure change rate is higher than or equal to the predetermined threshold.

Abstract: Embodiments of the present disclosure may estimate the amount of ammonia adsorbed in an SCR catalyst as accurate as possible. The ammonia adsorption amount is calculated by integrating the quantity of ammonia supplied to the SCR filter, the quantity of ammonia consumed in reduction of NOx in the SCR catalyst, and the quantity of ammonia desorbed from the SCR catalyst. In the calculation, a differential pressure change rate defined as the increase in a converted differential pressure value per unit increase in the filter PM deposition amount is referred to. The ammonia desorption quantity is calculated in such a way that the calculated value of the ammonia desorption quantity is made smaller when the differential pressure change rate is smaller than a predetermined threshold than when the differential pressure change rate is equal to or higher than the predetermined threshold.

Abstract: An abnormality diagnosis apparatus includes an exhaust gas purification apparatus arranged in an exhaust passage of an internal combustion engine and including a SCR catalyst; a supply apparatus supplying an additive such as ammonia to the exhaust gas purification apparatus; an EGR apparatus recirculating a part of exhaust gas from the exhaust passage at a downstream side of a position of supplying the additive to an intake passage; obtaining means for obtaining a NOx inflow amount into the exhaust gas purification apparatus; diagnosing means for calculating a physical quantity correlated to a NOx purification performance of the exhaust gas purification apparatus using the obtained NOx inflow amount, and diagnosing that an abnormality has occurred in the exhaust gas purification apparatus when the physical quantity is smaller than a threshold; and correcting means for, when the additive is recirculated together with a part of the exhaust gas, correcting the threshold to a smaller value than when otherwise.

Abstract: An incorrect or wrong diagnosis in abnormality diagnosis of a sensor is suppressed. Provided at the downstream side of an NOx selective reduction catalyst is a sensor which detects NOx and ammonia in an exhaust gas flowing out of the NOx selective reduction catalyst, and in which the NOx and the ammonia react with each other. An amount of decrease in an output of the sensor due to a reaction of the NOx and the ammonia in the sensor is calculated based on the NOx and the ammonia flowing out of the NOx catalyst, and an abnormality diagnosis of the sensor is carried out based on this amount of decrease in the output of the sensor.

Abstract: An abnormality diagnosis apparatus includes: an exhaust gas purification apparatus arranged in an exhaust passage of an internal combustion engine and including a selective catalytic reduction catalyst; a supply apparatus supplying an additive such as ammonia to the exhaust gas purification apparatus; an EGR apparatus recirculating a part of exhaust gas from the exhaust passage at a downstream side of a position of supplying the additive to an intake passage; calculating means for calculating a NOx inflow amount into the exhaust gas purification apparatus using a parameter indicating an operating state of the internal combustion engine; diagnosing means for diagnosing an abnormality in the exhaust gas purification apparatus using the calculated NOx inflow amount as a parameter; and correcting means for, when a part of the exhaust gas is recirculated, increasingly correcting the calculated NOx inflow amount in accordance with an amount of the additive to be recirculated together with exhaust gas.

Abstract: A diagnostic apparatus for an exhaust gas purification apparatus including a selective catalytic reduction NOx catalyst (SCR catalyst) provided in an exhaust passage of an internal combustion engine, a supplying unit supplying ammonia or an ammonia precursor into exhaust gas flowing into the SCR catalyst and a sensor, provided on a downstream side of the SCR catalyst, detecting NOx and ammonia in exhaust gas. The diagnostic apparatus calculates an amount of decline in output of the sensor due to a reaction between NOx and ammonia at the sensor and performs a diagnosis of the supplying unit based on the calculated amount of decline in output of the sensor.

Abstract: An exhaust control system for an internal combustion engine comprises: a trapping capability acquisition part that obtains information regarding a PM trapping capability, based on a detection value of an exhaust sensor provided to detect a predetermined parameter relating to an exhaust gas flowing out of an SCRF; and a NOx reduction capability acquisition part obtains information regarding a NOx reduction capability, based on an amount of NOx in the exhaust gas flowing out of the SCRF. The exhaust control system determines and distinguishes between a trapping abnormal state in which a PM trapping function by the SCRF is failed and a sensor abnormal state in which a detection function of the predetermined parameter by the exhaust sensor is failed, based on the NOx reduction capability obtained by the NOx reduction capability acquisition part, when the trapping capability obtained by the trapping capability acquisition part is in a predetermined low trapping capability state.

Abstract: An amount of reducing agent adsorbed on a NOx catalyst when a reducing agent supply device is normal and a corresponding detected value may be estimated. The corresponding detected value may be detected by a NOx sensor, and the detected value may correspond to an amount of reducing agent adsorbed on the NOx catalyst. When the estimated amount of adsorption is larger than or equal to a first amount and is smaller than or equal to a second amount, a diagnosis of the NOx catalyst based on the detected value of the NOx sensor may be prevented. The first amount may be an amount of adsorbed reducing agent corresponding to a minimum value of the corresponding detected value. The second amount may be an amount of adsorbed reducing agent corresponding to the corresponding detected value when the amount of adsorbed reducing agent is zero and larger than the first amount.