A carbon dioxide absorbent, its preparation method and its application method

Abstract

A preparation method of a CO2 absorbent comprises the following steps: alkali metal nitrate and an Mg-based precursor are mixed in certain mass ratio; a mixed solution obtained in the last step is dried and subjected to calcined activation at the temperature of 375-450 DEG C, and the required CO2 absorbent is obtained. The invention further provides the CO2 absorbent prepared with the preparation method and an application method of the CO2 absorbent. A Mg-based substance as a raw material for preparing the absorbent is widely sourced, the preparation method of the absorbent is simple and feasible, the absorption temperature and the regeneration temperature of the absorbent are both about 400 DEG C, and regeneration energy consumption of the absorbent can be reduced; the application method is beneficial to increase of the energy consumption rate of the absorbent and has great significance in enhancement of the engineering applicability of the Mg-based CO2 absorbent.

Description

technical field [0001] The invention relates to a medium-temperature dry carbon capture technology, more specifically to a carbon capture technology that can be used for CO2 under medium-temperature gas conditions and is prepared by modifying magnesium-based materials with alkali metal nitrates. 2 Carbon dioxide absorber for absorbing and regenerating, method for its preparation and method for its use. Background technique [0002] The use of fossil energy is accompanied by a large amount of greenhouse gas CO 2 emissions. With economic growth and people's increasing demand for energy, China is under increasing pressure to reduce greenhouse gas emissions. Therefore, the development of cost-effective CO 2 Capture and separation technology is imminent. Integrated gasification combined cycle power generation technology (IGCC) combines coal gasification with high-efficiency combined cycle, which can generate high-efficiency power generation and has good environmental protecti...

AI Technical Summary

Problems solved by technology

[0004] Calcium-magnesium double salt CO prepared by coprecipitation method using alkali metal calcium-magnesium nitrate and sodium carbonate reported in existing research 2 Absorbent, and the calcium-magnesium double salt CO prepared by modifying dolomite and limestone minerals with alkali metal nitrate 2 Absorbent, the existing problem is that although the absorption performance of the absorbent is stable, the absorbent CO 2 The absorption capacity is not high, only 0.20g CO 2 / g absorbent about

Based on this, existing studies have also reported the use of NaNO 3 or KNO 3 Preparation of Mg-based CO by direct modification of MgO 2 Absorbent, at this time the initial absorption capacity of the absorbent can reach up to 0.6g CO 2 / g absorbent, but its absorption performance will decrease during the initial cycle, and its absorption capacity will drop by nearly 50% when it reaches the 8th cycle, down to 0.3g CO 2 / g absorbent is stable after about 100 g, and the absorption reaction rate of the absorbent is very slow

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