氨水吸收CO_2的一级反应动力学研究

Kinetics Experimental Study of CO_2 Absorption by Hydroxyethylethylenediamine and Piperazine Compound Solution

CO_2作为最主要的温室气体,其控制与减排已刻不容缓。有机胺化学吸收法脱除烟气中的CO_2是目前公认的最为行之有效的方法之一。氨水是一种高效吸收剂,研究氨水溶液及其复配溶液吸收CO_2反应动力学,不仅可以揭示吸收过程的反应机理,亦可以为吸收工艺和工业设备的设计提供依据,为其工业化应用奠定基础。在温度298.15~303.15K、常压条件下,基于快速拟一级反应模式初步研究了氨水吸收CO_2的反应动力学,建立了简化的动力学方程。求解了CO_2-NH_3·H_2O系统的反应速率表达式r_(CO_2-NH_3solution)=k_2[NH_3][CO_2],同时求解了CO_2-NH_3·H_2O系统反应速率常数K_G=0.2331mmol·s^(-1)·m^(-2)·kPa^(-1)。对比CO_2-NH_3·H_2O与CO_2-MEA系统的动力学数据,结果表明,MEA溶液在负载0~0.4的KG值是293.15K、6 mol·L-1氨水各负载下KG值的1.5~2倍左右,所得结果可以为工业应用提供依据。

At present,CO2 is considered to be the most greenhouse gas,and it is imperative to control and reduce it. Organic amine method of chemical absorption to remove CO2 from flue gas is one of the most effective way. NH3·H2O is a potential new type of highly efficient absorbent,and in this paper,the kinetics of CO2 absorption by AEEA solution and its composite solution is studied by experimental methods. Using fast pseudo-first-order reaction,a series of experiments were investigated under atmospheric pressure over a range of temperature from 298. 15 K to 313. 15 K,the experimental study on the absorption of CO2 by NH3·H2O aqueous solution was carried out. And a simplified kinetic equation is established. By Comparing the the kinetic datas of CO2-NH3·H2O system and CO2-MEA system,the results showed that the KG value of MEA solution at loading 0 - 0. 4 was 293. 15 K,6 mol/L,and the 1. 5 - 2 value of KG under each load of ammonia water. The results can provide a basis for industrial application.