DEVELOPMENT OF A CELLULOSE ACETATE HOLLOW-FINE-FIBRE MEMBRANE
Journal: Acta Chemica Malaysia (ACMY)
Author: Akram Tawari, Bashir Brika, SM Bradshaw, EP Jacobs
Print ISSN : 2576-6732
Online ISSN : 2576-6724
This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited
The goal of this study is to produce cellulose acetate (CA) hollow-fine-fibre membranes with good water flux performance in the 95 – 96% salt retention range for brackish water desalination. A dry-wet spinning technique was used for the preparation of the hollow-fine-fibre membranes. Hollow-fine fibres were spun using CA dissolved in a suitable solvent and non-solvent mixture comprising acetone and formamide. The effects of the dope composition and spinning parameters such as solvent to non-solvent ratio, bore fluid ratio, take-up speed, dope extrusion rate and heat treatment on the membrane morphology and performance were investigated. The elimination of macrovoids from the morphology of hollow-fine-fibre membranes was achieved in two ways. Firstly, increasing the formamide ratio in the polymer solution and secondly, decreasing the water activity in the bore fluid by adding a solvent (acetone) to water. The mechanical strength of the fibres increased with increasing take-up speeds. This could be attributed to the higher orientation caused by higher take-up speeds. CA hollow-fine-fibre membrane showed good salt retention at an annealing temperature of 86 °C and annealing period of two subsequent times. The developed hollow-fine-fibre membranes showed a good brackish water desalination performance within brackish water operating conditions.