Method for recycling carbon-based microporous materials to treat nitrogen oxide waste gas

Abstract

The invention provides a method for recycling carbon-based microporous materials to treat nitrogen oxide waste gas, which belongs to the field of nitrogen oxide waste gas treatment and can efficiently and repeatedly utilize carbon-based microporous materials to absorb nitrogen oxide waste gas at normal temperature. The method for recycling carbon-based microporous materials to treat nitrogen oxide waste gas comprises the following steps: (1) stacking carbon-based microporous materials in an adsorption column, and feeding nitrogen oxide waste gas at normal temperature for adsorption; (2) completing the adsorption Finally, take out the carbon-based microporous material that absorbs nitrogen oxide waste gas, place it in a reactor, add a reducing agent, mix, and heat the reactor after sealing; (3) After heating, cool down, open the reactor, and then heat and dry. Take out the dried carbon-based microporous material, cool it to room temperature, stack it in the adsorption column, and repeat the operation of steps (1)-(2).

Description

technical field [0001] The invention relates to the field of nitrogen oxide waste gas treatment, in particular to a method for recycling carbon-based microporous materials to treat nitrogen oxide waste gas. Background technique [0002] Nitrogen oxides can cause environmental problems such as acid rain, photochemical smog, and ozone layer depletion, and are mainly composed of nitrogen monoxide and nitrogen dioxide. Nitrogen dioxide is easily soluble in water or lye and is also easily absorbed, and can be removed by absorption method, while nitric oxide, as a supercritical fluid, has relatively stable chemical properties and is difficult to remove by ordinary lye absorption method or urea reduction method , but the nitrogen oxides in smoke and vehicle exhaust are mainly composed of low concentrations of nitric oxide. For the treatment of nitrogen oxide waste gas, the selective catalytic reduction method is mainly used in industry. This method uses ammonia as a reducing agent...

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Problems solved by technology

[0004] However, the reusability of carbon-based microporous materials such as AC and ACF is poor. This is because the surface of carbon-based materials is easily oxidized by nitrogen dioxide-like complexes formed by nitric oxide and oxygen to form acidic oxygen-containing energy groups. Acidic oxygen-containing functional groups are not conducive to the adsorption of nitric oxide. As the number of cycles increases, its adsorption performance will become worse and worse. Studies have shown that carbon-based microporous materials will lose their adsorption capacity after heating and cycling for 2-3 times. The adsorption capacity of nitric oxide leaves only the oxidative capacity, but its oxidative capacity alone is not sufficient to achieve high removal rates in the presence of relative humidity

Existing research is mainly carried out under the condition of zero relative humidity, and there is no relevant achievement on the efficient and repeated use of carbon-based microporous materials to adsorb nitrogen oxides in exhaust gas, especially nitric oxide.

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