无机盐活化剂—氨基酸盐基溶液捕集温室气体CO_2

CO_2 capture through membrane gas Absorption with aqueous solution of inorganic salts-amino acid salts

将无机盐K3PO4、K2HPO4和KH2PO4作为活化剂,分别添加于氨基乙酸盐溶液中,形成CO2活化吸收剂,采用膜接触器-再生循环装置,评价和比较了氨基乙酸盐和活化吸收剂捕集CO2的性能,研究了活化剂的浓度、气液流速等因素对总体积传质系数、传质通量和捕集率的影响。结果表明,磷酸盐活化剂在氨基乙酸盐吸收剂中,对CO2的捕集均产生影响,活化效应存在PO43->HPO42->H2PO4-的规律;添加少量活化剂的作用比添加较多量的活化作用大;活化吸收剂的捕集率明显大于非活化吸收剂;膜吸收流体力学状态的改变,能够改善膜接触器传质性能,增大传质通量,但增大的程度有限。

K3PO4, K2HPO4, and KH2PO4 as activating agents were added into the aqueous solution of amino acid salts glycine （GLY） to form activated absorbents （AAh） for CO2 capture. The performances of GLY and AAb for CO2 capture were evaluated using a membrane contactor-regeneration cycled setup. The effects of activating agent concentration and flow rate on overall voluminal mass transfer coefficient, mass transfer flux, and capture efficiency were studied. The phosphates exhibited remarkable activating effects on CO2 capture in the membrane contactor; the activation extents of the phosphates were in the order of PO4^3- 〉 HPO4^2- 〉 H2PO4^- A small amount of activating agent is sufficient to promote the CO2 capture. The changes of hydrodynamics in the membrane contactor can improve mass transfer performance and enhance mass transfer flux to a certain extent; the essential factor for enhancing the mass transfer efficiency in membrane gas absorption is the performance of absorbents used.