A porous ceramic honeycomb body including a substrate of intersecting porous walls forming axial channels extending from a first end face to a second end face. An active portion of the walls include a zeolite catalyst disposed inside pores thereof and/or is comprised of an extruded zeolite and a three way catalyst (TWC) is disposed on wall surfaces of at least a portion of the active portion.

To be able to produce an SCR catalyst (2), in particular one having a zeolite fraction (Z) as catalytically active fraction, in a reliable process and at the same time achieve good catalytic activity of the catalyst (2), an inorganic binder fraction (B) which is catalytically inactive in the starting state and has been treated to develop catalytic activity is mixed into a catalyst composition (4). The inorganic binder component for the binder fraction (B) is, in the starting state, preferably porous particles (10), in particular diatomaceous earth, which display mesoporosity. To effect catalytic activation, the individual particles (10) are either coated with a catalytically active layer (12) or transformed into a catalytically active zeolite (14) with maintenance of the mesoporosity.

A method for reducing the level of occluded alkali metal cations from an MSE-framework type molecular sieve comprises either (a) contacting the molecular sieve with a solution containing ammonium ions at a temperature of at least about 50 C. to ammonium-exchange at least part of the occluded potassium ions or (b) contacting the molecular sieve with steam at a temperature of at least about 300 C. and then subjecting the steamed molecular sieve to ammonium exchange.

A porous ceramic honeycomb body including a substrate of intersecting porous walls forming axial channels extending from a first end face to a second end face. An active portion of the walls include a zeolite catalyst disposed inside pores thereof and/or is comprised of an extruded zeolite and a three way catalyst (TWC) is disposed on wall surfaces of at least a portion of the active portion.

Systems, apparatus and methods are provided for reducing reductant consumption in an exhaust aftertreatment system that includes a first SCR device and a downstream second SCR device, a first reductant injector upstream of the first SCR device, and a second reductant injector between the first and second SCR devices. NOx conversion occurs with reductant injection by the first reductant injector to the first SCR device in a first temperature range and with reductant injection by the second reductant injector to the second SCR device when the temperature of the first SCR device is above a reductant oxidation conversion threshold.

Hydrocarbon (HC) traps are disclosed. The HC trap may include a first zeolite material having an average pore diameter of at least 5.0 angstroms and configured to trap hydrocarbons from an exhaust stream and to release at least a portion of the trapped hydrocarbons at a temperature of at least 225 C. The HC trap may also include a second zeolite material having an average pore diameter of less than 5.0 angstroms or larger than 7.0 angstroms. One or both of the zeolite materials may include metal ions, such as transition, Group 1A, or platinum group metals. The HC trap may include two or more discrete layers of zeolite materials or the two or more zeolite materials may be mixed. The multiple zeolite HC trap may form coke molecules having a relatively low combustion temperature, such as below 500 C.

A catalytic converter includes a hydrocarbon catalyst trap including BEA zeolite configured to adsorb iso-octane at ambient temperatures and desorb iso-octane at temperatures between 150 C. and 170 C., and active metal supercage impregnated USY zeolite configured to adsorb and coke iso-octane at temperatures greater than 150 C.

A system comprising (i) a vehicular compression ignition engine comprising one or more engine cylinders and one or more electronically-controlled fuel injectors therefor; (ii) an exhaust line for the engine comprising: a first emissions control device comprising a first honeycomb substrate, which comprises a hydrocarbon adsorbent component; and a second emissions control device comprising an electrically heatable element and a catalysed second honeycomb substrate, which comprises a rhodium-free platinum group metal comprising platinum, wherein the electrically heatable element is disposed upstream from the catalysed second honeycomb substrate and wherein both the electrically heatable element and the catalysed second honeycomb substrate are disposed downstream from the first honeycomb substrate; a third emissions control device, which is a third honeycomb substrate comprising an ammonia-selective catalytic reduction catalyst disposed downstream from the second emissions control device; and one or more temperature sensors located: upstream of the electrically heatable element and/or upstream of the first honeycomb substrate; and between the electrically heatable element and the catalysed second honeycomb substrate; and (iii) an engine control unit comprising a central processing unit pre-programmed, when in use, to control both a heating activation state of the electrically heatable element; an injection timing strategy of the one or more electronically-controlled fuel injector to increase the temperature of at least the first emissions control device following key-on/cold-starting a vehicle comprising the system, wherein the one or more temperature sensors are electrically connected to the engine control unit for feedback control in the system.

A porous ceramic honeycomb body including a substrate of intersecting porous walls forming axial channels extending from a first end face to a second end face. An active portion of the walls include a zeolite catalyst disposed inside pores thereof and/or is comprised of an extruded zeolite and a three way catalyst (TWC) is disposed on wall surfaces of at least a portion of the active portion.

A method for reducing the level of occluded alkali metal cations from an MSE-framework type molecular sieve comprises either (a) contacting the molecular sieve with a solution containing ammonium ions at a temperature of at least about 50 C. to ammonium-exchange at least part of the occluded potassium ions or (b) contacting the molecular sieve with steam at a temperature of at least about 300 C. and then subjecting the steamed molecular sieve to ammonium exchange.