Non-metal doped low-temperature SCR catalyst and preparation method thereof

Abstract

The invention relates to a non-metal doped low-temperature SCR catalyst which separately comprises the following components in percentage by weight: 84-86wt% of a carrier titanium dioxide, active ingredients: 2-5wt% of vanadium pentoxide and 3-5wt% of ceric oxide, 5-7wt% of an auxiliary agent tungsten trioxide and doped elements: 0.4-2wt% of fluorine and 0.4-2wt% of sulfur. The invention also provides a preparation method of the catalyst. By doping non-metal elements fluorine and sulfur into the SCR catalyst, the low-temperature activity of the catalyst can be improved, so that a denitration device can be directly mounted behind a dust collector for a low-temperature denitration catalyst, or even behind a desulfurizing device, so that on the one hand, the catalyst poisoning probability isreduced and the service life is prolonged, and on the other hand, the flue gas repeated heating step is reduced, so that the cost is lowered.

Description

technical field [0001] The invention relates to the field of SCR catalysts, in particular to a low-temperature SCR catalyst doped with non-metal elements and a preparation method thereof. Background technique [0002] Nitrogen oxides (NO X ) is one of the main air pollutants, which will form acid rain, photochemical smog, destroy the ozone layer, and affect the ecological environment. There are two main sources of nitrogen oxides in the atmosphere, mobile sources and stationary sources. At present, CO and CH in exhaust gas are mainly used for mobile sources X , under the action of the three-way catalyst, the NO in the exhaust gas X Reduction to nitrogen and removal. NO emissions from stationary sources X The most effective solution is NH 3 Selective Catalytic Reduction (SCR), which is a reducing agent, has the advantages of high denitrification efficiency and mature technology. Catalysts are basically based on V 2 o 5 As an active component, TiO 2 as a carrier, and...

AI Technical Summary

Problems solved by technology

Catalysts are basically based on V 2 o 5 As an active component, TiO 2 as a carrier, and then adding WO 3 or MoO 3 As a co-catalyst, the catalyst temperature is about 300℃~350℃, and the reaction temperature window is relatively narrow, which belongs to the medium-high temperature catalyst. Therefore, the SCR reactor is generally placed before the dust collector, but the undusted flue gas will have a strong impact on the catalyst. Corrosion and poisoning, affecting service life