Preparation method and application of Cu-SSZ-13 catalyst

Abstract

The invention provides a preparation method and application of a Cu-SSZ-13 catalyst. The preparation method comprises the following steps: 1) putting raw materials including a silicon source, an aluminum source, a template agent and seed crystals into a mortar, and grinding to form a uniform mixture; 2) feeding the mixture into a reaction kettle and crystallizing; after cooling, washing and drying, roasting to obtain an Na-SSZ-13 molecular sieve carrier; 3) preparing an ammonium nitrate solution, and adding into the Na-SSZ-13 molecular sieve carrier; after carrying out ion exchange, filtering, washing and drying to obtain an NH4-SSZ-13 molecular sieve; 4) preparing a copper nitrate solution and adding into the NH4-SSZ-13 molecular sieve; after carrying out ion exchange, filtering, drying and roasting to obtain the Cu-SSZ-13 catalyst. The Cu-SSZ-13 catalyst prepared by the preparation method has excellent NH3-SCR (Selective Catalytic Reduction) catalytic activity, N2 selectivity, hydrothermal stability, and H2O and SO2 positioning resisting properties, and is applicable to purification of tail gas of diesel vehicles.

Description

technical field [0001] The invention relates to the technical field of catalysts, in particular to a preparation method and application of a Cu-SSZ-13 catalyst. Background technique [0002] Currently, in NH 3 Selective catalytic reduction of NOx(NH 3 -SCR), because of its high NOx conversion rate, good fuel economy, simple engine control and other advantages, has been widely used in diesel vehicle exhaust purification, and the catalyst is the core of this technology. where V 2 o 5 -WO 3 (MoO 3 ) / TiO 2 Catalysts have been used industrially for many years, but there are still some disadvantages, such as narrow operating temperature window, N 2 Low selectivity, active component V has biological toxicity, endangers the ecological environment and human health, etc. Other developed non-V catalysts, such as oxide catalysts Ce-W, Fe-Ti, and Cu-based or Fe-based molecular sieve catalysts supported by ZSM-5, beta, etc., have narrow temperature operating windows and poor hydro...

AI Technical Summary

Problems solved by technology

At present, the commonly used method for preparing Cu-SSZ-13 catalyst is liquid phase ion exchange method, but the preparation of SSZ-13 support by this method requires the use of expensive template N, N, N-trimethyladamantane ammonium hydroxide, which is not conducive to the Large-scale promotion and application of catalysts

In order to reduce the production cost of the catalyst, the technology of preparing Cu-SSZ-13 with cheap templates such as Cu-TEPA complexes or choline chloride has also received extensive attention, but the Cu-SSZ-13 catalyst prepared by it has The hydrothermal stability still needs to be further improved

At the same time, the crystallization process of all preparation methods is completed in a liquid phase environment, which not only produces sewage in the preparation process, but also has a low yield.

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