The present invention relates to crystalline zeolites with an ERI/CHA intergrowth framework type and to a process for making said zeolites. The ERI content of the zeolites ranges from 10 to 85 wt.-%, based on the total weight of ERI and CHA. The zeolites may further comprise 0.1 to 10 wt.-% copper, calculated as CuO, and one or more alkali and alkaline earth metal cations in an amount of 0.1 to 5 wt.-%, calculated as pure metals. The process for making the zeolites with an ERI/CAH intergrowth framework type comprises a) the preparation of a first aqueous reaction mixture comprising a zeolite of the faujasite framework type, Cu-TEPA and a base M(OH), b) the preparation of a second aqueous reaction mixture comprising a silica source, an alumina source, an alkali or alkaline earth metal chloride, bromide or hydroxide, a quaternary alkylammonium salt and hexamethonium bromide, c) combining the two reaction mixtures, and d) heating the combination of the two reaction mixtures to obtain a zeolite with an ERI/CHA intergrowth framework type. The ERI/CHA intergrowth zeolite may subsequently be calcined. The zeolites according to the present invention are suitable SCR catalysts.

A system for controlling reductant spray momentum for a target spray distribution includes an exhaust system having an exhaust conduit with exhaust flowing therethrough, a reductant injection system for injecting reductant into the exhaust flowing through the exhaust system based on one or more injection parameters, a reductant supply system for supplying reductant to the reductant injection system based on one or more supply parameters, and a controller. The controller is configured to access current vehicle, engine, exhaust, or reductant condition parameters, determine one or more control parameters based on a control model and the accessed current CZ vehicle, engine, exhaust, or reductant condition parameters, and modify a value of the one or more injection parameters or the one or more supply parameters to control the reductant spray.

Arrangement (100) for an exhaust gas aftertreatment system (102), comprising a tank (104) for storing a reducing agent (106); a pump unit arrangement (108) arranged in downstream fluid communication with the tank; a nozzle (110) arranged to inject a flow of reducing agent into the exhaust gas aftertreatment system (102), the nozzle being arranged in downstream fluid communication with the tank, via the pump unit arrangement, by means of a reducing agent conduit (112); an air conduit (114) arranged in fluid communication with the nozzle (110) for delivery of compressed air to the nozzle; and a return conduit (116) arranged in fluid communication between the reducing agent conduit and the tank, the return conduit comprising a return conduit valve arrangement (118), wherein the air conduit (114) is arranged in fluid communication with the reducing agent conduit (112) for controllably delivery of reducing agent to the tank via the return conduit valve arrangement (118) by means of providing compressed air from the air conduit to the reducing agent conduit.

The present disclosure relates to a process for preparing a zeolitic material having framework type AEI and having a framework structure which comprises a tetravalent element Y, a trivalent element X, and O. Further, the present invention disclosure relates to a zeolitic material having framework type AEI and having a framework structure which comprises a tetravalent element Y, a trivalent element X, and O, preferably obtained by the process, and further relates to the use of the zeolitic material as a catalytically active material, as a catalyst, or as a catalyst component.

The present disclosure relates to copper-containing molecular sieve catalysts that are highly suitable for the treatment of exhaust containing NOx pollutants. The copper-containing molecular sieve catalysts contain ion-exchanged copper as Cu.sup.+2 and Cu(OH).sup.+1, and DRIFT spectroscopy of the catalyst exhibits perturbed T-O-T vibrational peaks corresponding to the Cu.sup.+2 and Cu(OH).sup.+1. In spectra taken of the catalytic materials, a ratio of the Cu.sup.+2 to the Cu(OH).sup.+1 peak integration areas preferably can be ≥1. The copper-containing molecular sieve catalysts are aging stable such that the peak integration area percentage of the Cu.sup.+2 peak (area Cu.sup.+2/(area Cu.sup.+2+area Cu(OH).sup.+1)) increases by ≤20% upon aging at 800° C. for 16 hours in the presence of 10% H.sub.2O/air, compared to the fresh state.

The present invention relates to a catalyst which comprises a carrier substrate of length L, which extends between a first end face a and a second end face b, and catalytically active material zones A, B and C of different composition, wherein—material zone A comprises palladium or palladium and platinum with a weight ratio of Pd:Pt>1, and cerium oxide, —material zone B comprises platinum or platinum and palladium with a weight ratio of Pt:Pd>1, and cerium oxide and/or cerium/zirconium mixed oxide, and—material zone C comprises platinum or platinum and palladium with a weight ratio of Pt:Pd>1, and a carrier oxide, and wherein—material zone B is arranged above material zone A, and—material zone C is arranged above material zone B, and, starting from the second end face b of the carrier substrate, extends over a length of up to 60% of the length L. The invention also relates to a catalyst arrangement containing said catalyst.

The present invention provides methods for low temperature desulfating sulfur-poisoned SCR catalysts, and emission control systems adapted to apply such desulfating methods, in order to regenerate catalytic NOx conversion activity. The methods are adapted for treating an SCR catalyst to desorb sulfur from the surface of the SCR catalyst and increase NOx conversion activity of the SCR catalyst, the treating step including treating the SCR catalyst with a gaseous stream comprising a reductant for a first treatment time period and at a first treatment temperature, wherein the first treatment temperature is about 350° C. or less, followed by a second treatment time period and a second treatment temperature higher than the first treatment temperature, wherein the molar ratio of reductant to NOx during the treating step is about 1.05:1 or higher.

The present disclosure generally provides catalysts, catalyst articles and catalyst systems including such catalyst articles. In particular, the catalyst composition includes a metal ion-exchanged molecular sieve ion-exchanged with at least one additional metal, which reduces the number of metal centers often present in metal promoted zeolite catalysts. Methods of making and using the catalyst composition are also provided, as well as emission treatment systems including a catalyst article coated with the catalyst composition. The catalyst article present in such emission treatment systems is useful to catalyze the reduction of nitrogen oxides in gas exhaust in the presence of a reductant while minimizing the amount of dinitrogen oxide emission.

A honeycomb filter includes a plugged honeycomb structure body which has cell rows arranged along one direction, in a cross section of the honeycomb structure body and including a first cell row constituted of at least one of an inflow cell and an outflow cell, and a through-cell, and a second cell row including no through-cells. A width P1 (mm) of the first cell row, a width P2 (mm) of the second cell row and a curvature radius R (μm) of a curved shape of corner portions of a polygonal shape of each cell satisfy a relation of Equation (1) below: Equation (1): 0.4 (R/1000)/((P1+P2)/2) 100 20.

The present disclosure relates to a device and a method for monitoring an SCR exhaust gas after-treatment device. The method involves monitoring of a ratio between reducing agent quantity and nitrogen oxide conversion, especially a ratio between ammonia quantity and nitrogen oxide conversion, of the SCR exhaust gas after-treatment device. The nitrogen oxide conversion is detected or determined with a cross sensitivity to ammonia. The method furthermore involves determining of an ammonia slip condition based on the monitored ratio between reducing agent quantity and nitrogen oxide conversion. The method may offer the benefit of being easily carried out and implemented in an easy manner.