Abstract: Multistage counter-current extraction process with alternating extraction and stripping is proposed to increase mass-transfer rate and decrease the number of stages. Based on a theoretical analysis, extraction cascade computation was made for two systems-extraction of ferric ions with N, N-di (1-methylheptyl) acetyl amide (N503), and extraction of H3PO4 with DBSO. The results of computation for the former system, when verified against experiment, showed that the extraction mass-transfer efficiency is notably higher than a common multistage counter-current process.

摘要： 本文从萃取传质过程的基本关系式出发,提出了采用萃取级和反萃级交替排列、以增大传质推动力,从而提高萃取传质速率、减少萃取级数的新的逐级萃取方式,具体交替排列方式视具体萃取工艺体系之不同而有所不同.从理论分析出发,采用了N,N-二(1-甲庚基)乙酰胺(N_(503))萃取铁和二丁基亚砜(DBSO)萃取磷酸两个萃取体系进行串级计算,并对前—萃取体系进行了实验验证.结果表明,采用萃、反交替排列的多级逆流萃取方式较之通用的多级逆流萃取方式确可收到提高萃取传质速率、减少萃取级数的效果.用小型萃取设备进行的连续流动实验还表明,实现萃、反交替的排列方式以采用逐级式萃取设备(如混合澄清槽或单台单级式的离心萃取器)为宜,在设备设计和布置方面不存在任何困难.