B01D2255/50

MOLECULAR SIEVE SSZ-106, ITS SYNTHESIS AND USE
20170253491 · 2017-09-07 ·

Disclosed herein is a new crystalline molecular sieve designated SSZ-106, its synthesis in the presence of a structure directing agent comprising 2,3-bis(N-methylpyrrolidin-1-ylmethyl)bicyclo[2.2.1]heptane dication, and its use as an adsorbent and a catalyst.

SCR CATALYST HAVING EXCELLENT SULFUR TOLERANCE

Provided is an SCR catalyst for removing nitrogen oxides (NO.sub.x) from exhaust gas, comprising: 0.01-70 wt % of zeolite having an average pore size of 5 Å or more; 25-90 wt % of titanium dioxide (TiO.sub.2); and 4-10 wt % of vanadium pentoxide (V.sub.2O.sub.5). The SCR catalyst according to the present invention exhibits denitrification performance in a low-temperature area that is superior to that of a conventional SCR catalyst, has improved tolerance for a sulfur compound, and also has an excellent regeneration rate.

Mixed template synthesis of high silica Cu-CHA

A transition-metal-CHA molecular sieve catalyst and mixed-template synthesis procedure are disclosed.

Particulate filters

A vehicular exhaust filter (2) comprising a porous substrate having an inlet face and an outlet face with the porous substrate comprising inlet channels extending from the inlet face and outlet channels extending from the outlet face is disclosed. The inlet channels and the outlet channels are separated by a plurality of filter walls having a porous structure. The vehicular exhaust filter (2) is loaded with a refractory powder having a tapped density before loading of less than 0.10 g/cm.sup.3 and the vehicular exhaust filter has a mass loading of the refractory powder of less than 10 g/l.

METHOD OF MAKING AFX ZEOLITES HAVING HIGH THERMAL STABILITY
20210394165 · 2021-12-23 ·

A method of forming an AFX zeolite in a hydrothermal synthesis that exhibits a silica to alumina (SiO.sub.2AI.sub.2O.sub.3) molar ratio (SAR) that is between 8:1 and 26:1; has a morphology that includes one or more of cubic, spheroidal, or rhombic particles with a crystal size that is in the range of about 0.1 micrometer (μm) to 10 μm. This AFX zeolite also exhibits a Brönsted acidity that is in the range of 1.2 mmol/g to 3.6 mmol/g as measured by ammonia temperature programmed desorption. A catalyst formed by substituting a metal into the framework of the zeolite exhibits about a 100% conversion of NO emissions over the temperature range of 300° C. to 650° C.

Process for the production of nitric acid with tertiary abatement of N2O and NOx
11202992 · 2021-12-21 · ·

A nitric acid production process, comprising tertiary abatement of N2O and NOx on a tail gas withdrawn from an absorption stage, said abatement including passing the tail gas over a sequence of a deN2O stage comprising a Fe-z catalyst and a deNOx stage comprising a V2O5-TiO2 catalyst in the presence of gaseous ammonia, wherein the tail gas at the inlet of deN2O stage and the tail gas at the inlet of deNOx stage have a temperature greater than 400° C.

Exhaust gas purifying catalyst

This exhaust gas purifying catalyst is provided with a substrate 10 and a catalyst layer 20 formed on a surface of the substrate 10. The catalyst layer 20 contains zeolite particles 22 that support a metal, and a rare earth element-containing compound 24 that contains a rare earth element. The rare earth element-containing compound 24 is added in such an amount that the molar ratio of the rare earth element relative to Si contained in the zeolite 22 is 0.001 to 0.014 in terms of oxides.

EXHAUST TREATMENT SYSTEM FOR A LEAN BURN ENGINE

The present invention relates generally to the field of exhaust treatment systems for purifying exhaust gas discharged from a lean burn engine. The exhaust treatment system comprises a Diesel Oxidation Catalyst (DOC), a Catalyzed Soot Filter (CSF), a reductant injector, an AEI zeolite based Selective Catalyzed Reduction (SCR) catalyst and an Ammonia Oxidation Catalyst (AMOX) downstream to the AEI zeolite based SCR catalyst.

CATALYTIC WASHCOAT WITH ADDED ALUMINA FOR NOx ABATEMENT

The present disclosure provides catalyst compositions for NOx conversion and catalytic articles incorporating such catalyst compositions. Certain catalyst compositions include a zeolite with a silica-to-alumina ratio from 5 to 20 and sufficient Cu exchanged into cation sites of the zeolite such that the zeolite has a Cu/Al ratio of 0.1 to 0.5 and a CuO loading of 1 to 15 wt. %; and a copper trapping component in a concentration in the range of 1 to 20 wt. %, the copper trapping component including a plurality of particles having a particle size of about 0.5 to 20 microns. Certain catalyst compositions include, as the copper trapping component, alumina present as a plurality of alumina particles with a D.sub.90 particle size distribution in the range of 0.5 microns to 20 microns.

Process for producing a catalyst and catalyst as such

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.