Strengthening of alumina tubular membrane by Al support and its application for oil-in-water stable emulsion

Abstract

This research presents the fabrication of thinner and robust alumina tubular membrane for application in high pressure atmosphere. Thinner alumina tubular membrane systems were fabricated with Al mesh support to enhance its mechanical stability. The Al supported alumina tubular membrane (ASATM) and unsupported alumina tubular membrane (USATM) of different thicknesses were formed and their mechanical stability was measured. The ASATM of thickness 1.8 to 18 μm are able to tolerate pressure gradient from 6.4 to 450 kPa respectively. From mechanical stability analysis of both membrane systems having thicknesses 9 and 18 μm, it was found that breaking strength of ASATM is 31 to 43 fold higher than USATM. Both of the membrane systems were tested for permeation of sunflower oil. ASATM leads USATM in fluid flow due to lower possible thickness and tolerance of higher transmembrane pressure (TMP). The ASATM of 18 μm thickness was used for preparation of oil-in-water (O/W) emulsion. At optimized conditions the ASATM produces nano emulsion with 183 nm mean droplet size and span value 0.342. The emulsion was tested for 130 days and did not find any significant change in droplet size for 120 days. To the best of our literature review such a high stable emulsion is never reported before using any other type of membrane. The ASATM is much beneficial in terms of mechanical stability, flow rate, fabrication time, cost and applicability.