Separation characteristics of acetone/water mixtures through sodium alginate/poly(vinyl pyrrolidone) membranes by vapor permeation and vapor permeation with temperature difference methods

Abstract

In this study the permeation and separation characteristics of acetone/water mixtures were investigated by vapor permeation (VP) and vapor permeation with temperature difference (TDVP) methods using sodium alginate/poly (vinyl pyrrolidone) (NaAlg/PVP) membranes crosslinked with calcium chloride. Membranes were prepared in different ratios (w/w) (100/0, 95/5, 90/10, 85/15, 80/20, 75/25) of NaAlg/PVP. The effects of blend ratio, feed composition, operating temperature and temperature of the membrane surroundings on the separation characteristics (separation factor, permeation rate) were studied for the acetone/water mixtures. The optimum NaAlg/PVP ratio, operating temperature and feed composition were determined as 75/25 (w/w), 40°C, and 20 wt% acetone, respectively. The separation factors decreased whereas permeation rates increased with the increase in permeation temperature for both VP and TDVP methods. In the TDVP method separation factors increased and the permeation rates decreased as the temperature of the membrane surroundings decreased. It was as observed that the permeation rate in TDVP method was lower than in VP; however the highest separation factor was obtained with TDVP method as 73.

Synthesis of magnetite in poly(vinyl alcohol) matrix and its use in separation of acetone/water mixtures via pervaporation, vapor permeation with and without temperature difference methods

“…Kondolot Solak E. and Ş anlı O. [25,42], Sommer S. and Melin T [43]. have investigated the effect of permeation temperature on the permeation flux and separation factor in VP and found similar results.…”

“…16), thus acetone molecules having larger molecular size (0.308 nm) than water molecules (0.193 nm) [25] would diffuse easily through the swollen membrane. Similar results were also found in other studies reported in the literature [25,36,41].…”

“…The composition of collected mixture was determined by Atago DD-5 type digital refractometer [25,26]. The sorption selectivity was calculated as follows;…”

“…Several articles are present in the literature on the separation of acetone/water mixtures [14e24] related to PV method. We have also studied the separation of acetone water mixtures by using sodium alginate-poly (vinyl pyrrolidone) membranes by pervaporation and evapomeation with and without temperature difference [25,26]. As a continuation of our work in the current study, we have aimed to design iron oxide containing PVA nanocomposite membranes to separate acetone/ water mixtures.…”