AQUEOUS 2-PHASE SYSTEM OF CATIONIC AND ANIONIC SURFACTANT MIXTURE ANDITS APPLICATION TO THE EXTRACTION OF PORPHYRINS AND METALLOPORPHYRINS

Aqueous two-phase system is obtained when a cationic surfactant with b igger alkyl polar head groups such as dodecyltriethylammonium bromide (C12NE) is mixed with an anionic surfactant like sodium dodecyl sulfat e (SDS) at certain surfactant concentrations and molar ratios, When C1 2NE is in excess, the top phase is opalescent and is a surfactant-rich micellar solution, while the bottom phase is transparent and is a dil ute micellar solution. Such a new aqueous two-phase separation system is employed in extractive separation practice. Several dyes with diffe rent chemical structure like anthraquinone, methyl red and methylene b lue partitioned in the two-phase system are investigated. Porphyrin co mpounds and metalloporphyrins, i.e., hematoporphyrin (hemato), uroporp hyrin (uro), Cu-TPPS4 (tetraphenylporphine tetrasulfonic acid), Zn-TPP S4, Cu-T-4(TAP)P (tetrakis(p-trimethylammoniophenyl) porphine), are al so extracted with the present two-phase system. It is found that hydro phobic as well as charge interaction between a substance partitioned i n the system and the micelles are predominant factors that govern the extraction. (C) 1998 Elsevier Science B.V. All rights reserved.