“Equilíbrio Líquido-Líquido em Misturas de Polietienoglicol ( 4.000 ou 6.000 ou 10.000 g mol-¹)+ Bissulfito de Sódio + Água em Diferentes Temperaturas”

Abstract

In several decades the Aqueous Two-Phase Systems (ATPS) have been widely studied as promising systems for separation, extraction, purification and pre-concentration of various analytes, particularly the biotechnological interest. While these systems are easy to prepared control of their physicochemical properties is dependent on many factors and so it is essential to know the phase behavior of the ATPS, expressed as a phase diagram for your application. This study aimed to the experimental study of liquid-liquid equilibrium in aqueous two-phase systems (ATPS) formed by mixing PEG (4,000, 6,000 and 10,000 g mol-¹) + sodium bisulfite + water at four temperatures of 288.15 to 318.15 K. each diagram was characterized by 5 mooring lines at each temperature. In the diagrams obtained was a significant shift in the locus of the binodal curves, leading to an increase of the biphasic region with increasing temperature. This characteristic shows a process of endothermic phase separation. Increasing the molecular weight of the polymer also promotes the formation of SAB. Kinetic studies with pH monitoring and composition of the phases in time showed that the balance in the ATPS studied is reached with around 3 pm at rest in the thermostatic bath. In the 72 hours interval of the kinetic study the ATPS were stable. The new ATPS were not obtained in the literature and may have potential application for separation processes with increased property as a chemical preservative sodium bisulfite