The present invention discloses a catalyst for preparing pyridine base from syngas. The catalyst includes a carrier, an active component, a first auxiliary and a second auxiliary. The carrier is molecular sieves. The active component is Rh. The first auxiliary is one or more of Mn, Fe, Na and La. The second auxiliary is one or more of Zn, Co, Cr, Bi and Cu. The active component Rh is 0.5-3% of a mass of the carrier. The first auxiliary is 0.05-5% of the mass of the carrier. The second auxiliary is 0.5-15% of the mass of the carrier. The present invention further discloses application of the catalyst to preparation of pyridine base by catalyzing syngas, where the syngas and an ammonia donor are used as reaction raw materials for reaction to generate pyridine base products. The catalyst of the present invention can couple a cyclization reaction of generating acetaldehyde through hydrogenation of carbon monoxide with a condensation reaction of aldehyde and ammonia to convert the syngas into the pyridine base through one-step catalysis, with a carbon monoxide conversion rate of 8-20% and a pyridine base selectivity of 10-18%.

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.

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.

An SCR catalyst for treating diesel exhaust gas has: a flow-through substrate with an inlet end, an outlet end, a substrate axial length extending from the inlet end to the outlet end and a plurality of passages defined by internal walls of the flow through substrate extending therethrough; a first coating disposed on the internal wall surface of the substrate, the surface defining the interface between the internal walls and passages, the first coating extending over 40 to 100% of the substrate axial length, the first coating having an 8-membered ring pore zeolitic material with copper and/or iron; a second coating extending over 20 to 100% of the substrate axial length, the second coating having a first oxidic material with titania, wherein at least 75 wt. % of the second coating is titania, calculated as TiO.sub.2, and 0 to 0.01 wt. % of the second coating is vanadium oxides, calculated as V.sub.2O.sub.5.

The present invention discloses a catalyst for preparing pyridine base from syngas. The catalyst includes a carrier, an active component, a first auxiliary and a second auxiliary. The carrier is molecular sieves. The active component is Rh. The first auxiliary is one or more of Mn, Fe, Na and La. The second auxiliary is one or more of Zn, Co, Cr, Bi and Cu. The active component Rh is 0.5-3% of a mass of the carrier. The first auxiliary is 0.05-5% of the mass of the carrier. The second auxiliary is 0.5-15% of the mass of the carrier. The present invention further discloses application of the catalyst to preparation of pyridine base by catalyzing syngas, where the syngas and an ammonia donor are used as reaction raw materials for reaction to generate pyridine base products. The catalyst of the present invention can couple a cyclization reaction of generating acetaldehyde through hydrogenation of carbon monoxide with a condensation reaction of aldehyde and ammonia to convert the syngas into the pyridine base through one-step catalysis, with a carbon monoxide conversion rate of 8-20% and a pyridine base selectivity of 10-18%.

SCR-active molecular-sieve based catalysts with improved low-temperature performance are made by heating a molecular-sieve in a non-oxidizing atmosphere with steam (hydrothermal treatment), or in a reducing atmosphere without steam (thermal treatment), at a temperature in the range of 600-900° C. for a time period from 5 minutes to two hours. The resulting SCR-active iron-containing molecular sieves exhibit a selective catalytic reduction of nitrogen oxides with NH.sub.3 or urea at 250° C. that is at least 50% greater than if the iron-containing molecular-sieve were calcined at 500° C. for two hours without performing the hydrothermal or thermal treatment.

SCR-active molecular-sieve based catalysts with improved low-temperature performance are made by heating a molecular-sieve in a non-oxidizing atmosphere with steam (hydrothermal treatment), or in a reducing atmosphere without steam (thermal treatment), at a temperature in the range of 600-900° C. for a time period from 5 minutes to two hours. The resulting SCR-active iron-containing molecular sieves exhibit a selective catalytic reduction of nitrogen oxides with NH.sub.3 or urea at 250° C. that is at least 50% greater than if the iron-containing molecular-sieve were calcined at 500° C. for two hours without performing the hydrothermal or thermal treatment.

The present invention provides a method for preparing acrylic acid and methyl acrylate. The method comprises passing the feed gas containing dimethoxymethane and carbon monoxide through a solid acid catalyst to generate acrylic acid and methyl acrylate with a high conversion rate and selectivity at a reaction temperature in a range from 180 to 400 and a reaction pressure in a range from 0.1 MPa to 15.0 MPa, the mass space velocity of dimethoxymethane in the feed gas is in a range from 0.05 h.sup.−1 to 10.0 h.sup.−1, and the volume percentage of dimethoxymethane in the feed gas is in a range from 0.1% to 95%.

A hydrocarbon trap is provided for reducing cold-start hydrocarbon emissions. The trap comprises a monolithic flow-through substrate having a porosity of at least 60% and including a zeolite loading of at least 4 g/in.sup.3 in or on its walls. A separate coating of a three-way catalyst is provided over the zeolite coating. The trap may further include an oxygen storage material. The hydrocarbon trap may be positioned in the exhaust gas system of a vehicle such that unburnt hydrocarbons are adsorbed on the trap and stored until the monolith reaches a sufficient temperature for catalyst activation.

A hydrocarbon trap is provided for reducing cold-start hydrocarbon emissions. The trap comprises a monolithic flow-through substrate having a porosity of at least 60% and including a zeolite loading of at least 4 g/in.sup.3 in or on its walls. A separate coating of a three-way catalyst is provided over the zeolite coating. The trap may further include an oxygen storage material. The hydrocarbon trap may be positioned in the exhaust gas system of a vehicle such that unburnt hydrocarbons are adsorbed on the trap and stored until the monolith reaches a sufficient temperature for catalyst activation.