Modification of kapok cotton fibres into porous cellulose triacetate beads for oil spill remediation efforts

Abstract

Marine oil spills have been widely reported and bioremediation is proposed to be an environmentally friendly approach to clean these spills. However, maintaining a high biomass of oil-degrading bacteria has been proven challenging. Here, a carrier that enables simultaneous bacterial immobilization and oil absorption is proposed as a solution. Porous cellulose triacetate beads (PCTBs) derived from cellulose triacetate powder was obtained through the acetylation of kapok fibres. This study revealed that PCTBs with both 12.5% and 16.67% w/v precipitated in distilled water showed greater crude oil absorbency of 2.4850 ± 0.1326 g/g and 1.9852 ± 0.2343 g/g, respectively. Reusability tests of PCTBs showed promising results with no reduction in oil absorption after five reabsorption cycles. Successful immobilization of the oil-degrading bacteria, Acinetobacter venetianus on PCTBs was achieved and enumeration of bacteria showed no statistically significant differences compared to those on kapok fibres despite the raw fibres having a larger surface area. The SEM analysis revealed that A. venetianus adhered to the outer and inner walls of the beads through secreted exopolysaccharides. PCTBs with oil-degrading bacteria are potentially able to simultaneously absorb and degrade oil, thus highlighting the novelty of a working alternative to sustainable oil spill mitigation.