Abstract: A wall flow type particulate filter (24) adapted to be arranged in an exhaust passage of an internal combustion engine in which combustion is performed in an excess of oxygen carries a solid acid. The solid acid has an acid strength which is higher than the acid strength of sulfurous acid and lower than the acid strength of sulfuric acid.

Abstract: A wall flow type particulate filter is arranged inside the exhaust passage of an internal combustion engine where combustion is performed under an excess of oxygen. The particulate filter carries a solid acid. The solid acid has a Hammett acidity function smaller than ?0.83 and larger than ?12 in the standard state. To remove the ash from the particulate filter, ash atomization processing for rendering the state of the particulate filter a state where the exhaust gas which flows into the particulate filter is lowered in concentration of oxygen and the particulate filter is raised in temperature is temporarily performed.

Abstract: A method of removing ash from a wall flow type particulate filter which is arranged in an exhaust passage of an internal combustion engine in which combustion is performed in an excess of oxygen for trapping particulate matter in exhaust gas, using a solid acid which is carried on the particulate filter, renders the state of the particulate filter a state where the exhaust gas which flows into the particulate filter is lowered in concentration of oxygen and the particulate filter is raised in temperature, and then renders the state of the particulate filter a state where the exhaust gas which flows into the particulate filter in an oxidizing atmosphere contains SOx.

Abstract: An internal combustion engine in which an SOx trap catalyst (13) for trapping SOx contained in the exhaust gas contains an oxygen adsorbing and releasing material (54) which can adsorb SO2 contained in the exhaust gas and an SOx storage material (55) which can store SOx in the form of sulfates. The SO2 which is contained in the exhaust gas is chemically adsorbed at the oxygen adsorbing and releasing material (54) without being oxidized. If the temperature of the SOx trap catalyst (13) becomes higher than the start temperature of adsorbed SO2 movement, the SO2 which is chemically adsorbed at the oxygen adsorbing and releasing material (54) is oxidized and stored in the form of sulfates in the SOx storage material (55).

Abstract: The present detector for detecting sulfur components includes a storage portion for storing SOx and NOx in the exhaust gas passing through an exhaust passage, in which the more an amount of stored SOx increases, the more an amount of NOx that can be stored decreases, estimates the amount of stored SOx on the basis of an amount of NOx stored in the storage portion, and detects an integrated amount of SOx passing through the exhaust passage during a given period or an value on the basis of the integrated amount. In the present detector, the estimating of the amount of stored SOx for detecting the integrated amount of SOx or the value on the basis of the integrated amount is prohibited when a current amount of NOx that can be stored is not stored in the storage portion.

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: The present detector for detecting sulfur components includes a storage portion for storing SOx and NOx in the exhaust gas passing through an exhaust passage, in which the more an amount of stored SOx increases, the more an amount of stored NOx decreases, and which does not release SOx but release NOx at a set temperature, and a temperature sensor, estimates the amount of stored SOx on the basis of a relationship between, after the storage portion becomes the set temperature by heating, a heating pattern of the storage portion and temperature change of the storage portion measured by the temperature sensor, and detects an integrated amount of SOx passing through the exhaust passage during a given period or an value on the basis of the integrated amount.

Abstract: An exhaust purification system in which when an air-fuel ratio of exhaust gas is leaner than a stoichiometric air-fuel ratio, a silver-alumina-based catalyst device releases adsorbed NO2 at a first set temperature and releases adsorbed NO at a second set temperature which is lower than the first set temperature. When the air-fuel ratio of the exhaust gas is leaner than the stoichiometric air-fuel ratio and the silver-alumina-based catalyst device is a third set temperature which is lower than the second set temperature, a temperature rise of the silver-alumina-based catalyst device is suppressed to maintain the silver-alumina-based catalyst device near the third set temperature, and at least part of the NO which is adsorbed at the silver-alumina-based catalyst device is oxidized to NO2 to be adsorbed at the silver-alumina-based catalyst device, then the suppression of the temperature rise of the silver-alumina-based catalyst device is lifted.

Abstract: An exhaust purification system of an internal combustion engine of the present invention comprises a silver-alumina-based catalyst device arranged in the engine exhaust system. When a temperature of the silver-alumina-based catalyst device becomes a second set temperature T2 lower than a first set temperature T1 at which the silver-alumina-based catalyst device releases NO2, and releases NO, the silver-alumina-based catalyst device is heated such that a temperature elevation rate thereof is increased to make the temperature T of the silver-alumina-based catalyst device be a third set temperature T3 between the first set temperature T1 and the second set temperature T2.

Abstract: The exhaust purification system of an internal combustion engine of the present invention is provided with an NOX storage reduction catalyst and a particulate filter which is arranged at the upstream side of the NOX storage reduction catalyst. When causing the NOX storage reduction catalyst to release the stored NOX, the particulate filter is raised to the temperature at which the particulate matter is oxidized, the flow rate of the exhaust gas which flows into the particulate filter is made to decrease, the air-fuel ratio of the exhaust gas which flows into the particulate filter is made rich, and the particulate matter which builds up on the particulate filter is made to oxidize to produce carbon monoxide.

Abstract: This exhaust gas purification device for an internal combustion engine is provided with a particulate filter disposed in an engine exhaust system, and a catalytic device disposed downstream of the particulate filter in the engine exhaust system. The catalytic device holds sulfuric acid as a sulfate and releases the product as SO2.

Abstract: A detector for detecting sulfur components having a storage portion for storing SOX and NOX in the exhaust gas passing through an exhaust passage and a temperature sensor for measuring a temperature of the storage portion. The detector includes a heater for heating the storage portion and determines the current heat capacity (C) of the storage portion on the basis of an increase in (T2?T1) the temperature of the storage portion measured by the temperature sensor and a quantity of heat (QH) generated by the heater when the heater heats the storage portion.

Abstract: In an internal combustion engine, inside of an engine exhaust passage, an NOx adsorption part and an NOx purification part are arranged. The NOx purification part has the property of reducing NOx which is contained in exhaust gas if the concentration of hydrocarbons is made to vibrate by within a predetermined range of amplitude and within a predetermined range of period. When NOx is to be desorbed from the NOx adsorption part, the current NOx which is contained in the exhaust gas and the NOx which is desorbed from the NOx adsorption part are reduced by making the concentration of hydrocarbons of the NOx purification part vibrate by the amplitude and period which are set for the current engine operating state, at least of which (?T·k) has been corrected so that the amount of hydrocarbons becomes greater.

Abstract: In an exhaust purification system of an internal combustion engine of the present invention, a silver-alumina-based catalyst device and NOX reducing catalyst device are arranged in the engine exhaust system. When a temperature of the silver-alumina-based catalyst device becomes a first set temperature T1 on the high temperature side, NOX released from the silver-alumina-based catalyst device is reduced by reducing material to be purified in the NOX reducing catalyst device. When the temperature of the silver-alumina-based catalyst device becomes a second set temperature on the low temperature side, NOX released from the silver-alumina-based catalyst device is reduced by reducing material to be purified in the NOX reducing catalyst device.

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: In an internal combustion engine, inside of an engine exhaust passage, a hydrocarbon feed valve (15) and an exhaust treatment catalyst (13) are arranged. On a substrate (45) of the exhaust treatment catalyst (13), a coat layer comprised of at least two layers of a top coat layer (46) and a bottom coat layer (47) is formed. The top coat layer (46) is comprised of an exhaust purification catalyst for reacting NOx contained in exhaust gas and reformed hydrocarbons, while the bottom coat layer (47) is comprised of an NOx absorption catalyst. The concentration of hydrocarbons which flows into the exhaust treatment catalyst (13) is made to vibrate within a predetermined range of amplitude and within a predetermined range of period. Due to this, NOx contained in exhaust gas and NOx desorbed from the NOx absorption catalyst (47) are reduced in the exhaust purification catalyst (46).

Abstract: An electronic control unit executing an algorithm so as to operate an exhaust purification system of an engine. The algorithm (1) commences a regeneration treatment by causing an amount of fuel supplied to a combustion process of the engine to increase so as to change an air-fuel ratio of exhaust gas of the engine from a first lean air-fuel ratio to a set rich air-fuel ratio and (2) causes uncombusted fuel to be supplied to a NOx catalyst device during at least one of: a first period in which an air-fuel ratio of the exhaust gas within the NOx catalyst device changes from the first lean air-fuel ratio to the set rich air-fuel ratio when the regeneration treatment is started; and a second period after an air-fuel ratio of the exhaust gas within the NOx catalyst device becomes a ratio indicating completion of the regeneration treatment.

Abstract: In an exhaust purification system of an internal combustion engine of the present invention, a silver-alumina-based catalyst device and NOX reducing catalyst device are arranged in the engine exhaust system. When a temperature of the silver-alumina-based catalyst device becomes a first set temperature TI on the high temperature side, NOX released from the silver-alumina-based catalyst device is reduced by reducing material to be purified in the NOX reducing catalyst device. When the temperature of the silver-alumina-based catalyst device becomes a second set temperature on the low temperature side, NOX released from the silver-alumina-based catalyst device is reduced by reducing material to be purified in the NOX reducing catalyst device.

Abstract: A detector for detecting sulfur components having a storage portion for storing SOX and NOX in the exhaust gas passing through an exhaust passage and a temperature sensor for measuring a temperature of the storage portion. The detector includes a heater for heating the storage portion and determines the current heat capacity (C) of the storage portion on the basis of an increase in (T2?T1) the temperature of the storage portion measured by the temperature sensor and a quantity of heat (QH) generated by the heater when the heater heats the storage portion.

Abstract: In an internal combustion engine, an NOx selective reduction catalyst (14) is arranged in an engine exhaust passage, and an NOx storage catalyst (12) is arranged in the engine exhaust passage upstream of the NOx selective reduction catalyst (14). When the amount of NOx stored in the NOx storage catalyst (12) exceeds a predetermined allowable value, the NOx storage catalyst (12) is raised in temperature to make the NOx storage catalyst (12) release the NOx. The amount of urea feed is decreased by exactly the amount of reduction of the calculated stored NOx amount with respect to the amount of urea feed determined from the engine operating state, and the amount of urea feed is increased by exactly the amount of reduction of the calculated released NOx amount with respect to the amount of urea feed determined from the engine operating state.