An internal combustion engine 1 is provided, in an exhaust passage thereof with an electrochemical reactor including: an ion conductive solid electrolyte layer; an anode layer arranged on a surface of the solid electrolyte layer; and a cathode layer arranged on a surface of the solid electrolyte layer and able to hold NO.sub.X. The engine includes a current control device for controlling the current supplied to the electrochemical reactor so as to flow from the anode layer through the solid electrolyte layer to the cathode layer. The current control device is configured so as to supply current to the electrochemical reactor at least temporarily while that internal combustion engine is stopped.

The present invention is directed to selective catalytic reduction catalysts that combine SCR activity with NOx absorber activity. In particular, the disclosed catalytic article includes a substrate having a first and a second material disposed thereon, wherein the first material includes a selective catalytic reduction (SCR) catalyst composition and the second material includes a nitrogen oxides (NOx) absorber composition, wherein the NOx absorber composition does not substantially oxidize ammonia, and wherein the catalytic article is effective to abate NOx from an engine exhaust gas stream. Emission treatment systems for treating an exhaust gas including a catalytic article of the invention are provided, particularly systems that include an injector adapted for the addition of ammonia to the exhaust gas stream located upstream of the catalytic article.

The present invention provides a honeycomb catalytic converter including: a honeycomb structured body in which multiple through-holes are arranged longitudinally in parallel with one another with a partition wall therebetween; and a noble metal supported on the honeycomb structured body, wherein the honeycomb structured body contains a ceria-zirconia composite oxide and alumina, and cerium on a surface of each partition wall has a lower concentration than cerium in a central portion of the partition wall in a thickness direction.

An electrochemical reactor is arranged inside an exhaust passage of an internal combustion engine and is provided with a plurality of groups of cells. Each group of cell has a plurality of cells, each cell has an ion conducting solid electrolyte layer, and an anode layer and cathode layer arranged on a surface of the solid electrolyte layer. Each group of cells is configured so that all of the exhaust gas flows into passages defined by cells configuring the group of cells and so that both of the anode layers and the cathode layers are exposed to each passage. The plurality of groups of cells are arranged aligned in a direction of flow of exhaust gas and different groups of cells are connected to a power source in parallel with each other.

A NO.sub.x adsorber catalyst and its use in an emission treatment system for internal combustion engines, is disclosed. The NO.sub.x adsorber catalyst comprises a first layer consisting essentially of a support material, one or more platinum group metals disposed on the support material, and a NO.sub.x storage material.

The present invention relates to a mixed oxide with enhanced resistance and NO.sub.x storage capacity. The mixed oxide may be used as a component of a NO.sub.x trap material in an exhaust system of an internal combustion engine. The invention also relates to a method for treating an exhaust gas from an internal combustion engine using the mixed oxide.

In an exhaust gas purification apparatus for an internal combustion engine, the apparatus comprising NOx storage reduction catalyst, and a controller comprising at least one processor is configured to carry out rich spike, wherein in cases where the storage amount of NOx is the same, in a period of time from the completion of the execution of the last rich spike to the start of the execution of the current rich spike, the controller makes a period of execution of the current rich spike longer, and/or a degree of richness of a rich air fuel ratio achieved by the execution of the current rich spike larger, in the case where a period of time in which a temperature of the NOx storage reduction catalyst becomes equal to or higher than a predetermined determination temperature is long than in the case where it is short.

An exhaust purification system includes a NOx-occlusion-reduction-type catalyst that occludes NOx in exhaust in a lean state and reduces and purifies the occluded NOx in exhaust in a rich state, and a NOx purge rich control unit that executes NOx purge of reducing and purifying the occluded NOx by putting the exhaust into the rich state by fuel injection control, where a catalyst temperature of the NOx-occlusion-reduction-type catalyst is equal to or higher than a catalyst temperature threshold value and a NOx occlusion amount of the NOx-occlusion-reduction-type catalyst is equal to or higher than an NOx occlusion amount threshold value, and executes the NOx purge when the catalyst temperature is lower than a catalyst temperature threshold value.

Provided are a novel synthesis technique for producing pure phase aluminosilicate zeolite and a catalyst comprising the phase pure zeolite in combination with a metal, and methods of using the same.

An exhaust purification system including a NOx catalyst 32 provided in an exhaust passage of an internal combustion engine 10 and purifying NOx in exhaust; a MAF sensor 40 for acquiring an air flow-rate of the internal-combustion engine 10; a control unit 60, 70 that execute catalyst regeneration treatment of recovering a NOx purification ability of the NOx catalyst 32 by performing, in combination, air-based control of reducing air flow-rate of the internal-combustion engine 10 to a predetermined target air flow-rate and injection-based control of increasing a fuel injection amount, wherein, in a case of executing the catalyst regeneration treatment, the control unit 60, 70 starts with the air-based control and starts the injection-based control when the air flow-rate acquired by the MAF sensor 40 is reduced to the target air flow-rate.