The disclosure aims to attain further early activation of a catalytic substance in a catalytic device arranged in an exhaust passage of an internal combustion engine. A catalytic substance and a microwave absorber are included in a catalytic layer of the catalytic device which is irradiated with a microwave in the exhaust passage. Then, in the catalytic layer, the catalytic substance is carried or supported by the microwave absorber without through other substances.

A heating device for an exhaust catalyst includes a first antenna and a second antenna. The heating device executes a specific radiation control for controlling operation of an electromagnetic wave generator to set a radiation state of an electromagnetic wave from the first antenna to be a different state from a radiation state of an electromagnetic wave from the second antenna. In such a case, the heating device acquires an intensity of an electromagnetic wave, of electromagnetic waves incident on the first antenna, and acquires an intensity of an electromagnetic wave, of electromagnetic waves incident on the second antenna. The heating device acquires a first temperature-correlated value for the first part based on the first electromagnetic wave intensity, and acquires a second temperature-correlated value for the second part based on the second electromagnetic wave intensity.

An object of the disclosure is to prevent the sensing accuracy of an exhaust gas sensor from being deteriorated by the effect of electromagnetic waves in an exhaust gas purification system for an internal combustion engine that is configured to apply electromagnetic waves to the exhaust gas purification device provided in an exhaust passage of the internal combustion engine. The disclosure is applied to an exhaust gas purification system for an internal combustion engine including an exhaust gas sensor located within the range of radiation of electromagnetic waves from a radiating device that radiates electromagnetic waves of a specific frequency to an exhaust gas purification device. The system suspends the radiation of electromagnetic waves from the radiating device during a sampling period in which sampling of the output value of the exhaust gas sensor is performed, even when a specific condition for performing the radiation is met.

A system includes an exhaust conduit coupled, at least first end of the exhaust conduit, to an internal combustion; a catalytic converter coupled to a second end of the exhaust conduit; and electromagnetic wave source configured to emit electromagnetic energy; and a wave guide, coupled at a first end to the electromagnetic wave source and at a second end to the exhaust conduit, and extending between the electromagnetic wave source and the exhaust conduit. The electromagnetic wave source is configured to provide the electromagnetic energy, via the wave guide, to exhaust gas traveling through the exhaust conduit.

The disclosure aims to attain further early activation of a catalytic substance in a catalytic device arranged in an exhaust passage of an internal combustion engine. A catalytic substance and a microwave absorber are included in a catalytic layer of the catalytic device which is irradiated with a microwave in the exhaust passage. Then, in the catalytic layer, the catalytic substance is carried or supported by the microwave absorber without through other substances.

The present disclosure is intended to improve HC purification performance of a catalytic device arranged in an exhaust passage of an internal combustion engine in a more suitable manner. A microwave absorber is distributed over a predetermined part in a catalytic layer of the catalytic device which is irradiated with a microwave in the exhaust passage of the internal combustion engine. Then, in the predetermined part in the catalytic layer, a content ratio of a first catalytic material, which is one of two kinds of catalytic materials of which HC purification performance is higher than that of the other, is higher than a content ratio of the first catalytic material in the other portion than the predetermined part in the catalytic layer.

The present disclosure provides an exhaust gas purification apparatus for motor vehicles that has succeeded in suppressing peeling of a coat layer from an exhaust gas purification catalyst. Such exhaust gas purification apparatus for motor vehicles comprises: an exhaust gas purification catalyst comprising a substrate and a coat layer coated on the substrate comprising a microwave-absorbing material, a noble metal, and aluminum oxide (Al.sub.2O.sub.3); and a microwave-generating apparatus for heating the microwave-absorbing material located ahead of the exhaust gas purification catalyst with respect to an exhaust gas flow direction, wherein the microwave-absorbing material includes NiFe.sub.2O.sub.4, the noble metal includes at least one metal selected from the group consisting of platinum (Pt), palladium (Pd), and rhodium (Rh), and contents of zinc oxide (ZnO) and copper(II) oxide (CuO) in the coat layer are equivalent to or lower than the given levels.

Aspects of the subject disclosure may include, for example, an emission control system that includes an emission control device having a plurality of passages to facilitate emission control of an exhaust gas from a vehicle engine. A controller generates a control signal to initiate induction heating of the emission control device. An electromagnetic field generator responds to the control signal by generating a power signal applied to a coil to cause the induction heating of the emission control device, wherein a frequency of the power signal is adjusted to control a power transferred to the coil.

An exhaust after treatment system provided in an exhaust passage of an internal combustion engine, comprising an adsorption layer having the function of adsorbing hydrocarbons in the exhaust, a catalyst layer arranged at the same position as the adsorption layer in the direction of flow of exhaust or at the downstream side from the adsorption layer and having an oxidation function of oxidizing the hydrocarbons, and a thermal energy generator generating thermal energy, in the thermal energy generated by the thermal energy generator, the thermal energy supplied to the catalyst layer being made larger than the thermal energy supplied to the adsorption layer.

There is provided an exhaust purification device including a particulate filter configured to collect particulates contained in an exhaust gas, an oxidation catalyst disposed in a front stage of the particulate filter and configured to have a carrier partially or entirely made of a material which absorbs a microwave, a housing in which the particulate filter and the oxidation catalyst are arranged, and a microwave generator configured to generate a microwave to be irradiated onto the oxidation catalyst in a direction to which the exhaust gas flows.