Influence of palm oil fuel ash, an agro-industry waste on the ultrafiltration performance of cellulose acetate butyrate membrane

Palm oil fuel ash (POFA), which is produced as waste during production of palm oil, was used as an alternative additive to prepare cellulose acetate butyrate (CAB) composite ultrafiltration membrane. Acid-activated-milled POFA was characterized by Brunauere-Emmette-Teller (BET) surface area analysis and infrared spectroscopy (IR). The effect of incorporation of POFA in CAB matrix was analyzed by contact angle, water uptake, and porosity studies. The studies revealed an enhancement in the hydrophilic nature of the composite membranes upon addition of POFA. The change in the morphology of the membranes was recorded by means of scanning electron microscopy (SEM) which revealed the changing asymmetric structure of the membrane. Pure water flux and antifouling studies indicated that the membranes exhibited enhanced flux recovery ratio, which was maximum for CAB 2 (87.6%) containing 2wt.% of POFA. The adsorption property of POFA in addition to CAB/POFA network helped in the humic acid removal from aqueous solution up to 86% for CAB 2.5 membrane.