Catalyst for low-temperature fuel gas flue gas demercuration and denitration and preparation method thereof

Abstract

The invention discloses a catalyst for low-temperature fuel gas flue gas demercuration and denitration and a preparation method thereof, the catalyst comprises an active component and an alumina carrier, the active component comprises CeO2 and CuO, the CeO2 accounts for 1.5%-2.5% of the mass fraction of the catalyst, and the CuO accounts for 2%-6% of the mass fraction of the catalyst; the preparation method comprises the following steps: S1, measuring the saturated water absorption capacity of dried gamma-Al2O3 carrier ball; s2, weighing a cerium nitrate reagent and a copper nitrate reagent according to a preset active component loading amount, dropwise adding deionized water with the same saturated water absorption amount, and fully dissolving to obtain an active component; s3, placing gamma-Al2O3 carrier balls in a mixing container, slowly dropwise adding the active component in the step S2 into the mixing container, stirring in the dropwise adding process, and placing on a magnetic stirrer for constant-temperature stirring and dipping; s4, placing the mixed container after impregnation in a muffle furnace for roasting, and cooling to obtain a catalyst; compared with the prior art, the prepared catalyst can control and reduce the content of Hg < 0 > and NO in flue gas at the same time.

Description

technical field [0001] The present invention relates to Hg 0 The combined control technology of (zero-valent mercury) and NO is applicable to the flue gas purification of gas boilers, specifically a catalyst for demercury and denitrification of low-temperature gas flue gas and a preparation method thereof. Background technique [0002] Mercury, as one of the main heavy metal pollutants, has attracted worldwide attention. Mercury in nature is distributed all over the world, and many ores contain mercury. Under normal temperature and pressure, mercury is a liquid silver-white metal with relatively stable chemical properties. Mercury vapor and mercury compounds are toxic and pose serious threats to human health and the ecological environment. [0003] In coal combustion flue gas, mercury forms are divided into oxidized mercury Hg 2+ , particulate mercury Hg p and elemental mercury Hg 0 , the migration and diffusion characteristics of different forms of mercury in the ecolog...

AI Technical Summary

Problems solved by technology

The traditional SCR system is located upstream of the air preheater, which is a high-temperature and high-dust environment, and the reaction temperature is between 300°C and 500°C, which is in line with the optimum activity temperature window of conventional catalysts, but it will cause blockage and poisoning of the SCR catalyst. Reduce catalyst activity and shorten life

The new SCR system is located downstream of the precipitator, in a low-temperature and low-dust environment, with less dust and toxic substances in the environment, and a longer service life of the catalyst, but the temperature is between 100°C and 300°C, which is lower than the maximum of conventional catalysts. Optimum active temperature window; In addition, the water content in the gas flue gas is relatively high