A honeycomb structure includes: a honeycomb structure body including a plurality of cells defined by a partition wall and serving as a through channel of fluid; and a plugging portion to alternately plug open end parts of the plurality of cells on one side as an inflow side of the exhaust gas and open end parts on the other side as an outflow side of the exhaust gas. The partition wall is loaded, on the side of the outflow cells, with an oxidation catalyst made of a transition metal oxide at least including Fe and Mn to oxidize NO gas or an oxidation catalyst made of a transition metal oxide loaded at CeO.sub.2 and at least including Fe and Mn to oxidize NO gas. The loading amount of the oxidation catalyst is 5.0 g/L or more and 50 g/L or less.

An after-treatment system includes, in series along an exhaust gas flow direction through the after-treatment system: a diesel oxidation catalyst (DOC), a diesel exhaust fluid (DEF) delivery device, a soot-reducing device and a selective catalytic reduction (SCR) catalyst.

In an exhaust gas purification apparatus for an internal combustion engine which is provided with an NOx catalyst arranged in an exhaust passage of the internal combustion engine, the present invention has for its problem to be solved to suppress an increase in exhaust emissions, which results from processing for raising the temperature of the NOx catalyst, to a small level. In order to solve the above-mentioned problem, the exhaust gas purification apparatus for an internal combustion engine of the invention is constructed such that when an amount of increase in the NO.sub.X removal rate becomes smaller with respect to an amount of rise in the temperature of the NOx catalyst, the execution of temperature raising processing is deferred, and processing to make small the flow rate of exhaust gas discharged from the internal combustion engine and processing to make small the amount of smoke discharged from the internal combustion engine are executed.

An apparatus comprises a housing comprising a housing first portion and a housing second portion. The housing first portion comprises a first joint portion overlapping a second joint portion of the housing second portion so as to form a housing joint. A clamp is positioned on the housing joint and comprises a base portion. A first surface of the base portion is positioned on the housing joint. A plurality of legs extend from the base portion towards the housing each of which are spaced from each other around the housing joint. A plurality of flange segments extend from each side of the base portion away from the housing. A band is positioned on a second surface of the base portion opposite the first surface and around the clamp. The band is positioned between the plurality of flange segments and operatively coupled to the housing via the clamp.

A motor vehicle emission control system includes a three zone catalytic converter component having a honeycomb support body with catalytically active coating having a precious metal content applied on the channel walls. The first coating zone extends in the longitudinal direction from the inlet-side end to a first coating boundary and has a first precious metal content. The second coating zone extends in the longitudinal direction from the first coating boundary to a second coating boundary situated downstream from the first coating boundary and has a second precious metal content that is lower than the first precious metal content. The third coating zone extends from the second coating boundary to the outlet-side end and has a third precious metal content that is lower than the second precious metal content. The coating has oxidation catalyst activity and is free of rhodium.

According to various embodiments, an exhaust treatment system includes a catalyst that is in direct contact with an exhaust stream, at least one sensor that senses a system parameter and produces one or more signals corresponding to the system parameter, and a controller that is configured to receive the one or more signals and control catalyst performance based on the one or more signals by regenerating the catalyst. Regenerating the catalyst includes increasing a temperature of the exhaust stream flowing to the catalyst and directing a reductant injector to adjust a flow rate of reductant being injected into the exhaust stream flowing to the catalyst.

A method for removing NO.sub.X from an oxygen-rich exhaust flow produced by a combustion source that is combusting a lean mixture of air and fuel may include passing the oxygen-rich exhaust flow through an exhaust aftertreatment system that includes a NO.sub.X oxidation catalyst that includes perovskite oxide particles, a NO.sub.X storage catalyst, and a NO.sub.X reduction catalyst.

An aftertreatment system comprises a SCR system, a first filter, and a second filter disposed downstream of the first filter and a bypass conduit providing a flow path bypassing the second filter. A valve is operatively coupled to the bypass conduit and is moveable between a closed position in which the exhaust gas flows through the second filter, and an open position in which at least a portion of the exhaust gas flows through the bypass conduit. A controller is operatively coupled to the valve configured to adjust the valve based on a first filtration efficiency of the first filter to cause the exhaust gas expelled into the environment from the aftertreatment to have a particulate matter count meeting particulate matter emission standards.

An exhaust gas purification apparatus includes: a reduction catalyst converter that reduces and purifies nitrogen oxides in exhaust gas; a tank that stores a liquid reducing agent or precursor thereof; and an injection nozzle that injects the liquid reducing agent or precursor thereof stored in the tank on an exhaust gas upstream side of the reduction catalyst converter. Some of the exhaust gas flowing through an exhaust pipe is diverted to the tank by a bypass pipe, to cause an exchange of heat between the diverted exhaust gas and the liquid reducing agent or precursor thereof stored in the tank, thereby thawing the liquid reducing agent or precursor thereof frozen in the tank.

In an exhaust gas purification apparatus provided in an exhaust as path of an engine, it is an object of the present invention to shorten a pipe length of a bypass path bypassing a purification catalyst as short as possible, thereby reducing initial costs. The exhaust gas purification apparatus includes a purification casing in which at least the purification catalyst is accommodated. The purification catalyst purifies exhaust gas from the engine. The purification casing is integrally provided with the bypass path separately from the purification path in which the purification catalyst exists. The bypass path makes the exhaust gas bypasses the purification catalyst without passing through the purification catalyst.