- 作者: Akita, Shigendo; Takeuchi, Hiroshi
- 中文摘要: --
- 英文摘要: Spontaneous phase-separation of aqueous nonionic surfactant solutions occurs at temperatures above the cloud point, and the two-phase system formed can be utilized as a separation medium. This water- based separation method is referred to as cloud point extraction. Polyoxyethylene nonyl phenyl ethers were used as a nonionic surfactant; then some aromatic compounds, and gold (III) and gallium (III) were selected as model solutes of organics and inorganics, respectively. Preferential partitioning of the solutes into a small volume of the coacervate phase was observed; thus the effects of operational parameters including surfactant and salt concentrations, settling temperature and surfactant variation on the extraction efficiency have been reviewed. For the organics, the extraction behavior in regard to the solution pH could be explained with each acid dissociation constant of the solutes. In the case of the inorganics, the results for cloud point extraction were compared with those of solvent extraction; a cascade process scheme for the gold recovery from a printed substrate was proposed as a practical application. This paper is a review of our previous works on cloud point extraction.
- 中文關鍵字: 濁點萃取; 非離子性界面活性劑; 水性相分離; 芳香族化合物
- 英文關鍵字: Cloud Point Extraction; Nonionic Surfactant; Aqueous Phase Separation; Aromatic Compound