Ascorbic acid is an organic compound with antioxidant properties. It is present in a pure enantiomeric form (L-ascorbic acid or vitamin C) in lemons, fruit juices and fresh vegetables. This compound in its pure form is very important for the pharmaceutical and food industries.
In recent years, the use of membrane technology has grown rapidly, this development is expected to increase due to the requirements of environmental protection and the increasingly competitive energy and techno-economic efficiency offered by these membrane processes. Currently, several membrane types are used in many industrial applications. Indeed, affinity polymer membranes are well-adopted systems for the treatment of liquid mixtures. Among the systems often used for these applications, polymer inclusion membranes (PIMs) and grafted polymer membranes (GPMs).
In this work, two polymeric membranes GPM and PIM with polysulfone (PSU) and polyvinyl alcohol (PVA) as respective polymer supports and cholic acid (CA) as common extractive agent were prepared and characterized using of various techniques, IR spectroscopy to study the composition and the SEM technique to study the morphology and porosity of the developed membranes. These membranes have been adopted to study oriented processes related to the facilitated extraction and recovery of the L ascorbic acid substrate. The macroscopic parameters, permeability, initial flux (P, J0), and microscopic parameters, apparent diffusion coefficient and association constant (D*, Kass) relative to the diffusion of the substrate through the organic membrane phase were determined. The results indicate that the parameter values evolve enormously with the temperature factor and the performance of the adopted membrane increases with the increase in temperature of the feed and receiving aqueous phases. The values of the activation parameters (Ea, DH¹ and DS¹) were determined, and the obtained results show that these oriented processes through these two membrane types are based on reversible association / dissociation reactions between the substrate S and the extractive agent T with formation of an unstable entity (ST), necessary for the migration of the substrate through the organic membrane phase. The results indicate that
Session: M8 - Separation of Bio-Products
Day: 15 March 2018
Time: 14:45 - 16:00 h