Abstract: A temperature sensor includes temperature detecting means and at least one of a catalyst and an adsorbent applied to the surface of the temperature detecting means. At least one of the catalyst and the adsorbent catalyzes an exothermic reaction of a reactant in gas on the temperature detecting means. A temperature that is increased by the exothermic reaction is detected by the temperature detecting means. The catalytic efficiency for the exothermic reaction of at least one of the catalyst and the adsorbent is reduced by sulfur poisoning. The temperature sensor is disposed upstream of an exhaust purification system. Accordingly, it is determined that the temperature sensor is subjected to sulfur poisoning if the temperature detected by the temperature sensor is below a prescribed temperature.

Abstract: In an exhaust gas purification apparatus of an internal combustion engine, there is provided a technique capable of suppressing a reduction in exhaust gas purification performance. The apparatus includes: an exhaust gas purification catalyst (6) that is arranged in an exhaust passage of the internal combustion engine for purifying an exhaust gas; an adsorption device (5) that is arranged at an upstream side of the exhaust gas purification catalyst, rises in temperature up to an upper limit temperature due to heat generated by adsorption thereto of an incoming first component, and falls in temperature after its temperature has reached said upper limit temperature; and a heat generating component supply unit (10) that supplies a second component which generates reaction heat in the exhaust gas purification catalyst, before the temperature of the adsorption device begins to fall.

Abstract: In an internal combustion engine, an SOX trap catalyst (13) which traps SOX contained in the exhaust gas is arranged upstream of an NOX storing catalyst (15) in an engine exhaust passage. When the NOX storing catalyst (15) should release NOX, auxiliary fuel is injected into a combustion chamber (2) at a combustible timing after the completion of injection of fuel into the combustion chamber (2) for generating the engine output. At this time, the auxiliary fuel is injected so that the air-fuel ratio A/F of the combustion gas in the combustion chamber (2) does not become below a minimum allowable air-fuel ratio M where SOX trapped at the SOX trap catalyst (13) will not be released.

Abstract: An exhaust purification system is provided with an NOx storage reduction catalyst arranged in an exhaust passage and an SOx trap material arranged upstream of the NOx storage reduction catalyst and removes SOx contained in exhaust gas. A main flow path has a secondary flow path connected to it. In the secondary flow path, a removal device is arranged for removing the sulfur constituent contained in fuel. The secondary flow path includes an opening and closing device. When the SOx removal rate of the SOx trap material becomes a predetermined removal rate judgment value or less or the concentration of the SOx which flows into the SOx trap material becomes a predetermined concentration judgment value or more, at least part of the fuel flowing through a main flow path is made to flow into the secondary flow path and run through the removal device.

Abstract: A metal compound (50) able to trap a sulfur component in exhaust gas is arranged in a flow path of the exhaust gas, a property of the metal compound (50) changing along with an increase of the amount of sulfur component trapped at the metal compound (50) is measured, and the cumulative value of the amount of SOX actually contained in the exhaust gas is calculated from the measured property. On the other hand, the assumed cumulative value of the amount of SOX, assumed to be contained in the exhaust gas when assuming that fuel or oil of a sulfur concentration assumed in advance is used, is calculated. It is judged if fuel or oil with a high sulfur concentration is being used from the actual cumulative value of the amount of SOX and the assumed cumulative value of the amount of SOX.

Abstract: An exhaust purification system is provided with an NOx storage reduction catalyst arranged in an exhaust passage and an SOx trap material arranged upstream of the NOx storage reduction catalyst and removes SOx contained in exhaust gas. A main flow path has a secondary flow path connected to it. In the secondary flow path, a removal device is arranged for removing the sulfur constituent contained in fuel. The secondary flow path includes an opening and closing device. When the SOx removal rate of the SOx trap material becomes a predetermined removal rate judgment value or less or the concentration of the SOx which flows into the SOx trap material becomes a predetermined concentration judgment value or more, at least part of the fuel flowing through a main flow path is made to flow into the secondary flow path and run through the removal device.

Abstract: The exhaust purification system of an internal combustion engine is provided with an NOX selective reduction catalyst which is arranged in an engine exhaust passage and which has the function of absorbing NOX which is contained in exhaust gas when an air-fuel ratio of inflowing exhaust gas is lean, releasing the absorbed NOX when the air-fuel ratio of the inflowing exhaust gas becomes a stoichiometric air-fuel ratio or rich, and selectively reducing the NOX and with a fuel addition valve which feeds fuel to the NOX selective reduction catalyst. In the case of the region near the stoichiometric air-fuel ratio in the region where the air-fuel ratio of the exhaust gas flowing into the NOX selective reduction catalyst is lean, the fuel addition valve is used to feed fuel to the NOX selective reduction catalyst to selectively reduce the NOX.

Abstract: A temperature sensor includes temperature detecting means and at least one of a catalyst and an adsorbent applied to the surface of the temperature detecting means. At least one of the catalyst and the adsorbent catalyzes an exothermic reaction of a reactant in gas on the temperature detecting means. A temperature that is increased by the exothermic reaction is detected by the temperature detecting means. The catalytic efficiency for the exothermic reaction of at least one of the catalyst and the adsorbent is reduced by sulfur poisoning. The temperature sensor is disposed upstream of an exhaust purification system. Accordingly, it is determined that the temperature sensor is subjected to sulfur poisoning if the temperature detected by the temperature sensor is below a prescribed temperature.

Abstract: An exhaust purification system of an internal combustion engine arranging in an engine exhaust passage an NOx storing reducing catalyst storing NOx contained in exhaust gas when an air-fuel ratio of inflowing exhaust gas is lean and reducing and purifying stored NOx when the air-fuel ratio of the inflowing exhaust gas becomes a stoichiometric air-fuel ratio or rich, which system is provided with an NOx production reducing means for reducing an amount of production of NOx produced in a combustion chamber due to change of a combustion state of the engine and temporarily reduces the amount of production of NOx by the NOx production reducing means when an amount of N2O flowing out from the NOx storing reducing catalyst is anticipated to exceed an allowable amount.

Abstract: In an exhaust gas purification apparatus of an internal combustion engine, there is provided a technique capable of suppressing a reduction in exhaust gas purification performance. The apparatus includes: an exhaust gas purification catalyst (6) that is arranged in an exhaust passage of the internal combustion engine for purifying an exhaust gas; an adsorption device (5) that is arranged at an upstream side of the exhaust gas purification catalyst, rises in temperature up to an upper limit temperature due to heat generated by adsorption thereto of an incoming first component, and falls in temperature after its temperature has reached said upper limit temperature; and a heat generating component supply unit (10) that supplies a second component which generates reaction heat in the exhaust gas purification catalyst, before the temperature of the adsorption device begins to fall.

Abstract: In an internal combustion engine, an SOX trap catalyst (13) which traps SOX contained in the exhaust gas is arranged upstream of an NOX storing catalyst (15) in an engine exhaust passage. When the NOX storing catalyst (15) should release NOX, auxiliary fuel is injected into a combustion chamber (2) at a combustible timing after the completion of injection of fuel into the combustion chamber (2) for generating the engine output. At this time, the auxiliary fuel is injected so that the air-fuel ratio A/F of the combustion gas in the combustion chamber (2) does not become below a minimum allowable air-fuel ratio M where SOX trapped at the SOX trap catalyst (13) will not be released.

Abstract: A metal compound (50) able to trap a sulfur component in exhaust gas is arranged in a flow path of the exhaust gas, a property of the metal compound (50) changing along with an increase of the amount of sulfur component trapped at the metal compound (50) is measured, and the cumulative value of the amount of SOX actually contained in the exhaust gas is calculated from the measured property. On the other hand, the assumed cumulative value of the amount of SOx, assumed to be contained in the exhaust gas when assuming that fuel or oil of a sulfur concentration assumed in advance is used, is calculated. It is judged if fuel or oil with a high sulfur concentration is being used from the actual cumulative value of the amount of SOX and the assumed cumulative value of the amount of SOx.

Abstract: A SOx trap catalyst, an oxidation catalyst, a particulate filter, an aqueous urea supply valve, and a NOx selective reduction catalyst are arranged in order from upstream to downstream in an engine exhaust passage. It is determined whether a discharge concentration of hydrogen sulfide H2S will become equal to or greater than a preset maximum concentration when SOx is released from the SOx trap catalyst. If it is estimated that the discharge concentration of the hydrogen sulfide H2S will become equal to or greater than the maximum concentration when SOx is released, an adsorbed ammonia amount adsorbed on the NOx selective reduction catalyst is reduced before SOx is released so that the discharge concentration of the hydrogen sulfide H2S is less than the maximum concentration when SOx is released.