Abstract: Utilizing the finding that the state of adsorption of NH3 on a selective reduction type NOx catalyst includes a weakly adsorbed state in which the adsorbed NH3 is useful for a reduction reaction of NOx and a strongly adsorbed state in which the adsorbed NH3 is not useful for the reduction reaction of NOx unless the state of adsorption is changed into the weakly adsorbed state, the apparatus of the invention includes an actual weakly-adsorbed amount-calculation NH3 that is adsorbed on the selective reduction type NOx catalyst in the weakly adsorbed state, and a dispensation control portion that performs a dispensation control of the reductant dispensed by a reductant-dispensation portion, according to the actual weakly adsorbed amount calculated by the actual weakly adsorbed amount calculation portion.

Abstract: A technique that, in an exhaust gas purification apparatus of an internal combustion engine, can avoid a decrease in a NOx purification rate by adding a reducing agent as continuously as possible, while avoiding NH3 from passing through a selective reduction type NOx catalyst to a downstream side thereof. The selective reduction type NOx catalyst has an active spot which purifies NOx by the use of NH3, and an adsorption site which adsorbs NH3, wherein a vicinity site, which is located in the vicinity of the active spot, and a distant site, which is located distant from the active spot, exist in the adsorption site. The addition of the reducing agent from the reducing agent addition part is controlled based on the desorption rate of NH3 in the vicinity site so as to continue to cause the NH3 adsorbed to the vicinity site to exist.

Abstract: An exhaust gas purification system is equipped with a burner in an exhaust passage upstream of an exhaust gas purification apparatus and having a burner combustion chamber in which flame is produced. When the temperature of the exhaust gas purification apparatus is raised, the burner produces flame that extends from the interior of the burner combustion chamber to the interior of the exhaust passage when the flow rate of the exhaust gas is not higher than a predetermined flow rate, and the burner causes the size of the flame to be smaller than when it is determined that the flow rate of the exhaust gas is not higher than the predetermined flow rate or to produce flame only in the interior of the burner combustion chamber when it is determined that the flow rate of exhaust gas is higher than the predetermined flow rate.

Abstract: An object of the present invention is to increase the flexibility in the layout of an exhaust gas purification system for an internal combustion engine including selective catalytic reduction catalyst provided in an exhaust passage of the internal combustion engine and an addition device for supplying reducing agent derived from ammonia to the selective catalytic reduction catalyst, without a deterioration of the performance in reducing nitrogen oxides. To achieve the object, the exhaust gas purification system for an internal combustion engine according to the present invention is configured to supply hydrocarbon at the same time when reducing agent derived from ammonia is supplied to the selective catalytic reduction catalyst, thereby producing reducing agent that is hard to be oxidized by a precious metal catalyst.

Abstract: A technique that, in an exhaust gas purification apparatus of an internal combustion engine, can avoid a decrease in a NOx purification rate by adding a reducing agent as continuously as possible, while avoiding NH3 from passing through a selective reduction type NOx catalyst to a downstream side thereof. The selective reduction type NOx catalyst has an active spot which purifies NOx by the use of NH3, and an adsorption site which adsorbs NH3, wherein a vicinity site, which is located in the vicinity of the active spot, and a distant site, which is located distant from the active spot, exist in the adsorption site. The addition of the reducing agent from the reducing agent addition part is controlled based on the desorption rate of NH3 in the vicinity site so as to continue to cause the NH3 adsorbed to the vicinity site to exist.

Abstract: A NOx selective reduction catalyst for reducing NOx by the ammonia adsorbed is disposed in an engine exhaust gas passage. As states of adsorption of ammonia by the catalyst, there are a first adsorption state of ammonia that occurs when the ammonia is adsorbed during low temperature and a second adsorption state of ammonia that occurs when the ammonia is adsorbed or has already been adsorbed during high temperature. The amount of adsorbed ammonia in the first state is restricted to control concentration of the ammonia that is in the first state and desorbed when the temperature of the catalyst increases so as to be not higher than an allowable concentration, and that in the second state is restricted to control concentration of the ammonia that is in the second state and desorbed when the temperature of the catalyst increases so as to be not higher than an allowable concentration.

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.

Abstract: An internal combustion engine wherein an HC treatment catalyst (12) having the function of adsorbing the HC in the exhaust gas is arranged upstream of the NOx selective reducing catalyst (14), an urea aqueous solution fed from the reducing agent feed valve (15) is arranged upstream of the HC treatment catalyst (12), urea, and NOx contained in the exhaust gas, and HC adsorbed on the HC treatment catalyst 12 are reacted with each other to form intermediate products having cyano groups, oximes, and amino groups, and these intermediate products are sent to the NOx selective reducing catalyst (14).

Abstract: An SOx trap catalyst able to trap SOx contained in the exhaust gas is arranged in an engine exhaust passage upstream of an NOx storing catalyst in an internal combustion engine. When the SOx trap rate of the SOx trap catalyst falls, fuel is added in the exhaust gas flowing into the SOx trap catalyst to form in the SOx trap catalyst a region in which an air-fuel ratio becomes locally rich. SOx released from the SOx trap catalyst in this region can be trapped in the SOx trap catalyst at the downstream side once again without flowing out from the downstream end of the SOx trap catalyst.

Abstract: In an exhaust purification system of an internal combustion engine comprising an exhaust purification device which receives a bad influence from SOX in the exhaust gas and a S trap device arranged upstream of the exhaust purification device, which can store SOX in the exhaust gas, an amount of SOX passing through the S trap device is integrated as an integrated value, each allowance value of the integrated value for each elapsed period from the start time of the use of the S trap device is set, and when the current integrated value exceeds the corresponding allowance value and between a first set period ago and the current time, fuel has been supplied into the fuel tank and engine oil has not been exchanged, it is determined that fuel with a high concentration of sulfur has been supplied into the fuel tank.

Abstract: In an internal combustion engine, a pair of NOx storing catalysts are arranged in series in an engine exhaust passage. When causing the upstream NOx storing catalyst to release NOx and store the released NOx in the downstream NOx storing catalyst, the oxygen concentration in the exhaust gas is temporarily reduced in a state where the exhaust gas is maintained at a lean air-fuel ratio. As opposed to this, when releasing NOx from the upstream NOx storing catalyst and the downstream NOx storing catalyst and reducing the NOx, the air-fuel ratio of the exhaust gas is temporarily switched from lean to rich.

Abstract: In the present exhaust purification system of an internal combustion engine, a particulate filter is arranged downstream of an NOx storage/reduction catalyst device and an S trap device is arranged upstream of the NOx storage/reduction catalyst device. A first fuel supplying device for supplying additional fuel for regeneration of the particulate filter to the exhaust system upstream of the S trap device or into the cylinder is provided. An amount of the additional fuel supplied by the first fuel supplying device is controlled to make the S trap device not release SOx. A second fuel supplying device is provided in the exhaust system between the NOx storage/reduction catalyst device and the particulate filter to make up for a deficiency of the additional fuel supplied by the first fuel supplying device in the regeneration treatment of the particulate filter.

Abstract: An object of the present invention is to produce O3 to be supplied to the exhaust gas of an internal combustion engine while suppressing deterioration of the fuel economy. An O3 production apparatus according to the present invention is an O3 production apparatus that produces O3 to be supplied to the exhaust gas of an internal combustion engine by generating a plasma, when the operation state of the internal combustion engine is a decelerating operation state in which the engine load becomes lower.

Abstract: In an internal combustion engine, an NOX purification catalyst (14) is arranged in the engine exhaust passage and an intermediate product producing catalyst (12) able to store NOX contained in the exhaust gas is arranged at the upstream of the NOX purification catalyst (14). The intermediate product producing catalyst (12) is fed with mist fuel, and intermediate products (33) comprising bonded molecules comprised of an NOX and hydrocarbon molecules more than an equivalent ratio with respect to an NOX molecule are produced from the NOX trapped in the intermediate product producing catalyst (12) or the NOX contained in the exhaust gas and the fed fuel.

Abstract: An exhaust purification system of an internal combustion engine is provided with a first NOX selective reduction catalyst which is arranged inside of an engine exhaust passage and which selectively reduces NOX by feed of a reducing agent, a second NOX selective reduction catalyst which is arranged inside of the engine exhaust passage at the downstream side of the first NOX selective reduction catalyst and which selectively reduces NOX by feed of a reducing agent, and a reducing agent feed device which feeds a reducing agent to the first NOX selective reduction catalyst. The system estimates the amount of adsorption of the reducing agent which is adsorbed at the second NOX selective reduction catalyst and prevents the estimated amount of adsorption of the reducing agent from exceeding the allowable value by adjusting the amount of feed of reducing agent from the reducing agent feed device.

Abstract: A metal or metal compound able to trap a sulfur component in exhaust gas is arranged in a flow passage of exhaust gas in an internal combustion engine. When the amount of sulfur component trapped in the metal or metal compound increases over the passage of time, a property of the metal or metal compound which changes along with the increase in the amount of trapped sulfur component is measured and the sulfur component in the gas is detected from the measured property.

Abstract: An internal combustion engine in which a front end catalyst (12) and rear end catalyst (14) comprising NOx storing catalysts are arranged in an engine exhaust passage. When these catalysts (12, 14) should recover from SOx poisoning, SOx poisoning recovery proceeding is performed in which the temperatures of the corresponding catalysts (12, 14) are raised to the SOx release temperature and the air-fuel ratio of the exhaust gas flowing into the corresponding catalysts (12, 14) is made rich. In this case, the frequency of performing the SOx poisoning recovery proceeding of the rear end catalyst (14) is made higher than the frequency of performing the SOx poisoning recovery proceeding of the front end catalyst (12).

Abstract: In an internal combustion engine, an NOX selective reducing catalyst is arranged in the engine exhaust passage, and an NOX storage catalyst able to store NOX contained in the exhaust gas is arranged at the upstream of the NOX selective reducing catalyst. The NOX storage catalyst is fed with mist fuel, and the NOX stored in the NOX storage catalyst and the fed fuel are used to produce an intermediate product comprising bonded molecules comprised of NH2 and a hydrocarbon molecule more than an equivalent ratio with respect to one NOX molecule. These intermediate products are adsorbed at the NOX selective reducing catalyst, whereby the adsorbed intermediate product reduces the NOX in the exhaust gas.

Abstract: A post-treatment system comprised of an SOx trapping catalyst (11), a particulate filter (13) carrying an NOx storing and reducing catalyst, and an NOx storing and reducing catalyst (15) and a fuel feed valve (17) for feeding fuel for post processing to the post-treatment system are arranged in an engine exhaust passage. Each time an operating period of the engine passes a certain period, values of operating parameters of the engine and the method of feeding the post-treatment use fuel are reset so that the total amount of consumption of the combustion use fuel and post-treatment use fuel becomes smallest while maintaining the amounts of the harmful components discharged into the atmosphere at below the regulatory values.

Abstract: When performing temperature elevation control at a first exhaust purification device, a second exhaust purification device is prevented from being raised in temperature to a set temperature or more.