Abstract
Xylitol is an important raw material in cosmetic, pharmaceutical and food industries due to its non-cariogenic sweetener properties. Xylitol in mixed sugars which obtained from fermentation media could be purified through adsorption or crystallisation. Xylitol may leach out during adsorption while the complexity of the fermentation broth in crystallisation has limits the utilisation of these techniques. The use of membrane filtration technique is foreseen could avoid these limitations as its separation is based on the solutes size, shape and/or molecular weight ranges. In this work, special blend polymer membranes were synthesised, characterised and tested in the xylitol recovery from synthetic solution. Pluronic F127 at 1 %, 3 %, and 5 % was blended with polyethersulfone (PES) to modify membranes. The effect of Pluronic ratio on the membrane selectivity for xylitol separation from sugars and also the fouling mitigation effect under Pluronic presence in the membranes were investigated. The results showed an improvement in the membrane hydrophilicity, where the contact angle of pure PES membrane has dropped from 80° to 65° in addition of Pluronic at different ratios. The water flux has also increased as the Pluronic ratio increased. The rejection of xylitol has found to decrease in Pluronic presence. Surprisingly, the membrane selectivity has enhanced greatly as desired. The PES blend Pluronic membranes have shown promising future in xylitol separation from sugars.
