A catalytic composition for treating a NOx-containing exhaust gas, wherein the composition comprises a copper-substituted small-pore zeolite comprising: i) Ce and/or La in a total amount of about 5 to about 400 g/ft.sup.3; and ii) Nd and/or Nb in a total amount of about 5 to about 400 g/ft.sup.3.

A method to determine a nitrogen oxide storage capacity of a catalytic converter of a vehicle in which a concentration of nitrogen oxides is measured in an exhaust gas downstream of the catalytic converter includes, in at least one first step, setting a concentration of nitrogen oxides in the exhaust gas at which the catalytic converter absorbs nitrogen oxides, and in at least one second step, setting a concentration of nitrogen oxides in the exhaust gas at which a desorption of nitrogen oxides by the catalytic converter takes place. The nitrogen oxide storage capacity of the catalytic converter is determined by considering a behavior of the catalytic converter at least during the desorption of nitrogen oxides.

Methods and systems for reducing emissions of an internal combustion engine are described. In one example, an electric heater and a passive NOx absorber or other emissions control device are positioned in a passage downstream of a combustor so as to process emissions from the combustor before an engine is started.

A system that may include an exhaust gas source that provides exhaust gas pollutants, a primary catalytic converter coupled downstream of the exhaust gas source, and an adsorption unit, configured to adsorb exhaust gas pollutants. The adsorption unit may be coupled downstream of the exhaust gas source. A process that may include introducing exhaust gas comprising exhaust gas pollutants into a system that includes an adsorption unit, such that the exhaust gas may flow through the adsorption unit and the exhaust gas pollutants may be adsorbed into an adsorption media in the adsorption unit as adsorbed exhaust gas pollutants. A depleted exhaust gas may pass from the adsorption unit.

An object of the present disclosure is to provide an NO.sub.x storage material having sufficient NO.sub.x storage capacity even in a low temperature region and a production method thereof.

An NO.sub.x storage material including a composite oxide of silver and gallium. The composite oxide of silver and gallium is preferably a delafossite-type composite oxide. The composite oxide is produced by dissolving a silver salt and a gallium salt in a solvent and baking the solution, wherein the molar ratio of silver:gallium is preferably from 2:8 to 7:3.

The invention relates to an exhaust gas aftertreatment device for an internal combustion engine, where the device comprises: an exhaust duct allowing a through-flow of exhaust gas; a catalytic NOx converter arranged in the exhaust duct; and a fluid inlet arranged to introduce a liquid reductant into or onto a structure in the exhaust duct upstream the catalytic NOx converter. The invention is characterized in that the structure is a sorption structure having pores configured to retain the liquid reductant in liquid form until it evaporates. The invention also relates to a vehicle provided with such a device.

An exhaust gas purification apparatus for an internal combustion engine includes the adsorbent, the catalyst and the heat generating element, wherein in cases where the residual capacity of the battery is smaller than a first predetermined value required for raising the temperature of the catalyst to an activation temperature thereof, and in cases where the residual capacity of the battery is larger than a second predetermined value which is smaller than the first predetermined value and which is required for raising the temperature of the adsorbent to a predetermined temperature at which the adsorbent exhibits adsorption performance required at the time of starting of the internal combustion engine, an amount of electric power to be supplied to the heat generating element from the battery is adjusted such that the temperature of the adsorbent becomes the predetermined temperature.

An exhaust gas treatment apparatus is provided for use together with a diesel engine in an indoor environment, where the diesel engine is part of, e.g., a vehicle or other machinery. A method of controlling such an exhaust gas treatment apparatus is also provided.

An exhaust system for a compression ignition engine comprising: a water adsorbent material; and a catalyst composition for treating an exhaust gas pollutant produced by the compression ignition engine; wherein the water adsorbent material is: (i) arranged to contact exhaust gas from the compression ignition engine before the catalyst composition; and (ii) in thermal communication with the catalyst composition.

The present invention relates a system for the treatment of an exhaust gas of a diesel combustion engine, said system comprising a specific NOx adsorber component, a diesel oxidation catalyst (DOC) component, a selective catalytic reduction (SCR) component, a gas heating component, and a reductant injector, wherein in said system, the specific NOx adsorber component is arranged upstream of the gas heating component, the reductant injector is arranged up-stream of the SCR component, the gas heating component is arranged upstream of the reductant injector, the DOC component is arranged upstream of the reductant injector, and the DOC component and the gas heating component are directly consecutive components. Further, the present invention relates a process for preparing such a system and use thereof.