The present invention relates to a method for producing automobile exhaust gas catalytic converters, to the catalytic converters as such and to the use thereof. In particular, the method comprises a step which results, independently of the actual drying process, in the catalytically active material used being dried. The invention is especially used in the coating of wall-flow filters.

The present invention relates to a method for producing automobile exhaust gas catalytic converters, to the catalytic converters as such and to the use thereof. In particular, the method comprises a step which results in a smaller particle size of the catalytically active material used.

A particle filter for treating exhaust gases includes an SCR catalyst that, when in the presence of a reductant such as ammonia, promotes selective catalytic reduction of NO.sub.x; an active oxidation catalyst that promotes oxidation of hydrocarbons and carbon monoxide; and an oxygen storage catalyst that alternately stores and releases oxygen, enhances soot oxidation, and stores NOx at temperatures below optimal SCR functioning. The particle filter may be included in a system having an oxidation catalytic device (OCD) upstream of the particle filter, and optionally includes one or more SCR converters upstream and/or downstream of the particle filter, and/or an ammonia slip catalyst downstream of the particle filter. The system may further be adapted for operation under a high frequency injection fuel control with an OCD having substantial NOx storage material content, or an NSC for improving the efficiency tradeoffs between soot oxidation during filter regeneration and NO.sub.x reduction.

A CHA-type zeolite has a molar ratio of silica to alumina of 10.0 or more and less than 20.0 and a molar ratio of silanol groups to silicon of 0.1510.sup.2 or more and 0.5010.sup.2 or less, a molar ratio of silica to alumina of 20.0 or more and 35.0 or less and a molar ratio of silanol groups to silicon of 0.1510.sup.2 or more and 1.1010.sup.2 or less, a molar ratio of silica to alumina of more than 35.0 and 45.0 or less and a molar ratio of silanol groups to silicon of 0.1510.sup.2 or more and 1.6510.sup.2 or less, or a molar ratio of silica to alumina of more than 45.0 and 55.0 or less and a molar ratio of silanol groups to silicon of 0.1510.sup.2 or more and 1.8010.sup.2 or less.

A process for preparing C.sub.2 to C.sub.5 paraffins includes introducing a feed stream comprising hydrogen gas and a carbon-containing gas into a reaction zone of a reactor, and converting the feed stream into a product stream comprising C.sub.2 to C.sub.5 paraffins in the reaction zone in the presence of a hybrid catalyst. The hybrid catalyst includes a metal oxide catalyst component and a microporous catalyst component. The metal oxide catalyst component satisfies: an atomic ratio of Cu/Zn from 0.01 to 3.00; an atomic ratio of Cr/Zn from 0.01 to 1.50; and percentage of (Al+Cr) from greater than 0.0 at % to 50.0 at % based on a total amount of metal in the metal oxide catalyst component.

Direct conversion of syngas to light olefins is carried out in a fixed bed or a moving bed reactor with a composite catalyst A+B. The active ingredient of catalyst A is active metal oxide; and catalyst B is one or more than one of zeolite of CHA and AEI structures or metal modified CHA and/or AEI zeolite. A spacing between geometric centers of the active metal oxide of the catalyst A and the particle of the catalyst B is 5 m-40 mm. A spacing between axes of the particles is preferably 100 m-5 mm, and more preferably 200 m-4 mm. A weight ratio of the active ingredients in the catalyst A and the catalyst B is within a range of 0.1-20 times, and preferably 0.3-5.

Provided is a method for producing zeolite having a controlled aluminum content, wherein the sodium hydroxide molar concentration of a zeolite synthesis mixture can be adjusted to adjust the aluminum content in synthesized CHA. The structure of the low aluminum-content CHA produced by the provided method does not collapse even after high-temperature hydrothermal treatment, and thus the catalytic activity of the CHA can be maintained. Moreover, by adjusting the aluminum content in the framework, the properties of the produced CHA significantly change, and thus the CHA can be applied to various fields.

A batch process for preparing a zeolitic material having framework type CHA and a framework structure comprising Si, Al, O, and H, comprising (i) providing a seeding material comprising a zeolitic material having framework type CHA and a framework structure comprising Si, Al, O, and H; (ii) preparing a mixture comprising a source of Si, a source of Al, a seeding material provided in (i), a CHA framework structure directing agent comprising a cycloalkylammonium compound, and water, wherein the cycloalkylammonium compound is a compound comprising a cation R.sup.1R.sup.2R.sup.3R.sup.4N.sup.+ wherein R.sup.1, R.sup.2, R.sup.3 are, independently from one another, an alkyl residue having from 1 to 6 carbon atoms, and R.sup.4 is a 5- to 8-membered cycloalkyl residue, wherein in mixture, the molar ratio of water relative to Si comprised in the source of Si and in the seeding material, calculated as SiO.sub.2, is in the range of from 5:1 to 15:1, wherein the mixture, the molar ratio of sodium, calculated as Na.sub.2O, relative to Si comprised in the source of Si and in the seeding material, calculated as SiO.sub.2, is in the range of from 0:1 to 0.1:1; (iii) heating the mixture prepared in (ii) in its liquid state to a temperature of the mixture in the range of from 50 to 90 C. and keeping the liquid mixture at a temperature in this range for 5 to 100 h; (iv) heating the heated mixture of (iii) to a temperature of the mixture in the range of from 190 to 230 C. in a crystallization vessel and keeping the mixture at a temperature in this range under autogenous pressure in the crystallization vessel for 0.5 to 10 h, obtaining a solid material comprising a zeolitic material having framework type CHA and a framework structure comprising Si, Al, O, and H, suspended in its mother liquor.

To provide an exhaust gas purification catalyst that is less likely to cause an increase in pressure loss, even a large amount of zeolite-based SCR catalyst is used to improve NOx purification capability. The exhaust gas purification catalyst includes a DPF provided with zeolite having a primary particle size equal to or less than 0.5 m. In addition, it is preferable that 50% particle size of the zeolite measured by dynamic light scattering is equal to or less than 2.0 m, and further, it is preferable that the 90% particle size of the zeolite is equal to or less than 2.5 m.

Proposed is a reformed zeolite and a catalyst composite using the reformed zeolite which have improved heat resistance and are used in a selective catalytic reduction (SCR) catalyst using ammonia or urea as a reducing agent, in a filter-type selective catalytic reduction (SDPF) catalyst in which a filter is coated with the SCR catalyst, or in a lean nitrogen oxide diesel oxidation catalyst (NA-DOC). In the reformed zeolite and the catalyst composite, alumina components, which are a zeolite coating material, improve heat-resistance of the zeolite and promote catalytic efficiency in a high-temperature condition.