The present disclosure is directed to a Low Temperature NOx-Absorber (LT-NA) catalyst composition which exhibits NOx adsorption in a broad temperature and space velocity range, and shifts NOx desorption to a desired temperature range. In particular, the LT-NA composition includes a large pore zeolite containing a palladium component and a small or medium pore zeolite containing a palladium component. Further provided is a catalyst article including the LT-NA catalyst composition, an emission treatment system for treating an exhaust gas including the catalyst article, and methods for reducing a NOx level in an exhaust gas stream using the catalyst article.

A process for the preparation of an extra-framework metal-containing aluminosilicate zeolite involves the steps of: (a) forming a reactant mixture A comprising (i) an aqueous slurry of an aluminosilicate zeolite in a H.sup.+-form, and (ii) a metal containing compound or free metal, wherein the mixture does not comprise ammonia, ammonium hydroxide or an ammonium salt, and (b) reacting the metal containing compound or free metal with the aluminosilicate zeolite in a H.sup.+-form in reactant mixture A and forming a product mixture B, a reaction mixture comprising the extra-framework metal-containing aluminosilicate zeolite. The metal comprises one or more of copper, iron, manganese, nickel and palladium. The step of reacting the metal with the aluminosilicate zeolite in a H.sup.+-form is performed in a single exchange. The extra-framework metal-containing aluminosilicate zeolite can then be used directly in forming a washcoat that can be applied to a support.

A metal-containing chabazite zeolite, which has an FTIR peak area ratio between the peak at 900-1300 cm.sup.−1 (Si—O—Si asymmetric stretch) and the peak at 765-845 cm.sup.−1 (˜805 cm.sup.−1 is Si—O—Si symmetric stretch) of at least 55. A method for preparing metal-containing CHA zeolites with high SCR activity at low reaction temperatures from alkali cation-free reaction mixtures that contain the three OSDA structures: metal-polyamine, N,N,N-trimethyl-1-adamantyl ammonium (TMAda+) and TMAOH. The metal-containing CHA zeolites produced by the disclosed method can be identified by XRD, FTIR spectroscopy, FT-VIS spectroscopy, and scanning electron microscopy. A method of selective catalytic reduction of NOx in exhaust gas using the material described herein is also disclosed.

Processes are provided for the removal of hydrogen from a mixture. The process can be performed by contacting a mixture comprising hydrogen, oxygen, and one or more organic compounds with a synthetic zeolite to produce water or steam. The synthetic zeolite can include Si and Al and has a SiO.sub.2:Al.sub.2O.sub.3 molar ratio of greater than 4:1, an 8-membered ring zeolite having a framework type of AEI, AFT, AFX, CHA, CDO, DDR, EDI, ERI, IHW, ITE, ITW, KFI, MER, MTF, MWF, LEV, LTA, PAU, PWN, RHO, SFW or UFI, a degree of crystallinity of at least 80% as measured by ASTM D535-197, and at least 0.01 wt % of at least one catalytic metal, based on a weight of the synthetic zeolite, where the at least one catalytic metal can include Ru, Rh, Pd, Ag, Os, Ir, Pt, Au, Mo, W, Re, Co, Ni, Zn, Cr, Mn, Ce, Ga, alloys thereof, or mixtures thereof. At least 95% of the catalytic metal can be disposed within a plurality of pores of the synthetic zeolite.

A hydrogenolysis bimetallic supported catalyst comprising a first metal, a second metal, and a zeolitic support; wherein the first metal and the second metal are different; and wherein the first metal and the second metal can each independently be selected from the group consisting of iridium (Ir), platinum (Pt), rhodium (Rh), ruthenium (Ru), palladium (Pd), molybdenum (Mo), tungsten (W), nickel (Ni), and cobalt (Co).

A NO.sub.x absorber catalyst for treating an exhaust gas from a lean burn engine. The NO.sub.x absorber catalyst comprises a molecular sieve catalyst comprising a noble metal and a molecular sieve, wherein the molecular sieve contains the noble metal; an oxygen storage material for protecting the molecular sieve catalyst; and a substrate having an inlet end and an outlet end.

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 xenon adsorbent capable of efficiently adsorbing xenon, even at a low concentration, from a mixture gas is Provided. A xenon adsorbent comprising a zeolite having a pore size in the range of 3.5 to 5 Å and a silica alumina molar ratio in the range of 10 to 30.

Disclosed are passive NO.sub.x adsorbers and methods for synthesizing the same. Small-pore zeolitic materials with practical loadings of transition metals atomically dispersed in the micropores are described herein. Also demonstrated are simple and scalable synthesis routes to high loadings of atomically dispersed transition metals in the micropores of a small-pore zeolite.

The present invention relates to a process for producing LPG and BTX from a mixed feedstream comprising C5-C12 hydrocarbons by contacting said feedstream in the presence of hydrogen with a first hydrocracking catalyst and contacting the thus obtained first hydrocracked product in the presence of hydrogen with a second hydrocracking catalyst to produce a second hydrocracked product stream comprising LPG and BTX.