中文摘要：

提出一种溶剂萃取与Ca^2＋碳酸化的耦合反应过程,以三丁胺为萃取剂将HCl从水相萃取到有机相,在固定CO2的同时实现Ca Cl2的碳酸化,副产碳酸钙与氯化铵。实验结果显示,超过98%的Ca^2＋在1400s内沉淀为碳酸钙,反应后有机相迅速与水相实现分层,并通过与氨水反应再生,三丁胺回收率约为98%。采用粒径分布与显微镜观察证明了Ca^2＋沉淀过程发生在油包水结构中。以15%浓度的CO2作为碳源,反应时间为2700 s时,Ca^2＋沉淀率达到98.31%,显示该工艺将高成本的CO2捕集过程和封存过程集成,可处理低浓度烟气中的CO2。过程无须CO2捕集费用以及热量输入,同时副产碳酸钙和氯化铵产品,有望缓解常规CO2捕集封存技术高成本的难题。

英文摘要：

An intensified process by coupling the carbonation reaction and solvent extraction was proposed for CO2 mineralization in CaCl2-rich solution to capture CO2 and generate CaCO3 and NH4Cl. Tributylamine was used as the extractant to remove HCl from aqueous phase and precipitate CaCO3. Experiments showed that the precipitation ratio of Ca^2＋ reached ca. 98% at 1400 s. The organic phase could be spontaneously separated from the aqueous phase immediately after extraction, and recycled by reacting with NH3·H2O with a tributylamine regeneration ratio of ca. 98%. In addition, the experiment using low CO2 concentration （i.e., 15% CO2 in N2） could also reach a high level of 98.31% at a reaction time of 2700 s, which exhibited the potential to integrate CO2 capture and CO2 storage in a one-step process. The particle size distribution of calcite and the observation of water-in-oil structures indicated that the formation of calcite was occurred in the water-in-oil structures. This process, with simple apparatus, no heat input, unrequired CO2 capture cost and production of valuable CaCO3 and NH4Cl, greatly reduced the costs of CO2 sequestration, and might be an alternative method to solve the primary problem of the conventional high-cost CCS technology.