Cu-SAPO-34 molecular sieve catalyst and preparation method and application thereof

Abstract

The invention provides a Cu-SAPO-34 molecular sieve catalyst and a preparation method and application thereof. The method includes the steps of adding pseudo-boehmite to deionized water, stirring, adding fumed silica or silica sol and orthophosphoric acid, uniformly mixing, adding copper sulfate and tetraethylenepentamine, fully stirring, and adding diethylamine, triethylamine or n-propylamine; placing fully stirred gel in a hydrothermal reaction kettle for crystallization, cooling at room temperature, separating a solid crystalline product from the mother liquor, washing to be in neutral, drying, and calcinating in air at the temperature of 600 DEG C to 850 DEG C to obtain the Cu-SAPO-34 molecular sieve catalyst. The Cu-SAPO-34 molecular sieve catalyst prepared through a one-step hydrothermal synthesis method. And the molecular sieve catalyst of good NH3-SCR catalytic activity and hydrothermal stability is obtained by controlling the using amount of copper sulfate, tetraethylenepentamine and fumed silica or silica sol and the calcination temperature.

Description

technical field [0001] The invention belongs to the technical field of catalysts, and relates to a Cu-SAPO-34 molecular sieve catalyst, a preparation method and an application thereof. Background technique [0002] Take NH 3 Selective catalytic reduction of NOx or NH as a reducing agent 3 -SCR technology plays an extremely important role in the process of catalytic removal of NOx, and its key core is the development of SCR catalyst system. Due to the characteristics of diesel vehicles with variable operating conditions, large exhaust temperature changes, complex exhaust gas composition, and rapid flow changes, an excellent automotive catalyst must have the following properties: high catalytic activity in a wide temperature window, hydrothermal stability High resistance, high mechanical strength, anti-SO 2 And HC poisoning ability, anti-high airspeed ability and so on. While the current commonly used V 2 o 5 -WO 3 (MoO 3 ) / TiO 2 Although catalysts have been used indu...

AI Technical Summary

Problems solved by technology

However, if the copper content is too high, it is easy to form more CuO, and non-selective redox NH 3 , resulting in catalytic activity and N 2 Reduced selectivity

If the calcination temperature is low, the organic amine as the template cannot be completely removed, resulting in low crystallinity of the molecular sieve, small specific surface area and pore volume, and reduced catalytic activity.

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