The present invention relates to a catalyst comprising at least one oxide of vanadium, at least one oxide of tungsten, at least one oxide of cerium, at least one oxide of titanium and at least one oxide of antimony, and an exhaust system containing said oxides.

A method of preparing a mesoporous Fe—Cu—SSZ-13 molecular sieve includes activating an aluminum source, a silicon source, an iron source and a copper source respectively; mixing the activated minerals with sodium hydroxide, water and a seed crystal at 25-90° C., while controlling feeding amounts of respective raw materials so that molar ratios of respective materials in a synthesis system are as follows: SiO.sub.2/Al.sub.2O.sub.3=10-100, SiO.sub.2/Fe.sub.2O.sub.3=30-3000, SiO.sub.2/CuO=1-100, Na.sub.2O/SiO.sub.2=0.1-0.5, H.sub.2O/SiO.sub.2=10-50, template/SiO.sub.2=0.01-0.5; adding an acid source to adjust pH of the system for first aging; and adding the acid source again to adjust the pH of the system for second aging to obtain aged gel; pouring an aged mixture into a kettle; cooling a crystallized product and filtering to remove a liquor; washing a filter cake; drying to obtain a solid; performing ion exchange; and filtering, washing and drying the solid to obtain powder; and placing the powder in a muffle furnace.

An exhaust-gas treatment module for an exhaust system of an internal combustion engine has a plurality of elements which follow one another in an exhaust-gas flow direction. The elements include a first mixing path with a first reactant dispensing arrangement in an upstream end region of the first mixing path and with a first mixing channel which is elongate in the direction of a first mixing path longitudinal axis. A first exhaust-gas treatment arrangement follows and is elongate in the direction of a first exhaust-gas treatment arrangement longitudinal axis and has an upstream end region connected to a downstream end region of the first mixing path, a second mixing path with a second reactant dispensing arrangement in an upstream end region which is connected to a downstream end region of the first exhaust-gas treatment arrangement.

The present invention relates to a catalyst comprising at least one oxide of vanadium, at least one oxide of tungsten, at least one oxide of cerium, at least one oxide of titanium and at least one oxide of niobium, and an exhaust system containing said oxides.

The present invention relates to a catalyst comprising at least one oxide of vanadium, at least one oxide of tungsten, at least one oxide of cerium, at least one oxide of titanium and at least one oxide of niobium, and an exhaust system containing said oxides.

An abnormality determination apparatus for an ammonia sensor is usable in an exhaust purification system including a catalyst, a supply apparatus, an ammonia sensor, an NO.sub.X sensor, and an oxygen sensor. During a continuation period within which ammonia supply to the catalyst continues after the supply apparatus stops supply of reductant, the abnormality determination apparatus calculates the ammonia concentration on a downstream side of the catalyst as a first concentration value, based on an output of the ammonia sensor and an output of the oxygen sensor. During the continuation period, the abnormality determination apparatus calculates the ammonia concentration on the downstream side of the catalyst as a second concentration value, based on an output of the NO.sub.X sensor and the output of the oxygen sensor. The abnormality determination apparatus determines presence or absence of abnormality in the ammonia sensor based on the first concentration value and the second concentration value.

A passive NO.sub.x adsorber is disclosed. The passive NO.sub.x adsorber is effective to adsorb NO.sub.x at or below a low temperature and release the adsorbed NO.sub.x at temperatures above the low temperature. The passive NO.sub.x adsorber comprises a noble metal and a molecular sieve having an LTL Framework Type. The invention also includes an exhaust system comprising the passive NO.sub.x adsorber, and a method for treating exhaust gas from an internal combustion engine utilizing the passive NO.sub.x adsorber.

A method includes determining that at least one diesel emissions fluid (DEF) doser of an exhaust aftertreatment system is likely frozen based on at least one of an ambient air temperature or a DEF source temperature; operating an engine in a cylinder cutout mode in response to the determination that the at least one DEF doser is likely frozen; and, discontinuing the cylinder cutout mode in response to determining that the at least one DEF doser is in a predefined condition.

The present disclosure describes methods for evaluating quality of DEF dosed to an EAS including a close coupled SCR unit a downstream SCR unit. A NOx conversion efficiency of the close coupled SCR unit and a NOx conversion efficiency of the downstream SCR unit are used to evaluate quality of DEF. In some embodiments, the NOx conversion efficiency of close coupled SCR unit is used to evaluate quality of DEF. Operation of an EAS using the results of the evaluation of quality of DEF are described.

The present disclosure is directed to a system for treating an exhaust gas stream from an engine, which includes a diesel oxidation catalyst (DOC) located downstream of the engine and adapted for oxidation of hydrocarbons and carbon monoxide, an injector adapted for the addition of a reductant to the exhaust gas stream located downstream of the DOC, a catalyzed soot filter (CSF) located downstream of the injector, and a selective catalytic reduction component adapted for the oxidation of nitrogen oxides located downstream of the CSF. The CSF is adapted for oxidizing hydrocarbons and includes a selective oxidation catalyst composition on a filter with high selectivity ratio for hydrocarbon oxidation:ammonia oxidation (e.g., at least 0.6).