Effect of Dimethyl Sulfoxide (DMSO) as a Green Solvent and the Addition of Polyethylene Glycol (PEG) in Cellulose Acetate/Polybutylene Succinate (CA/PBS) Membrane’s Performance

Abstract

In this study, performance of CA/PBS membranes, prepared with the non-toxic solvent dimethyl sulfoxide (DMSO) compared to Dimethylformamide (DMF), was investigated. The membranes were prepared using immersion precipitation technique at coagulation bath at temperatures of 25°C. Ternary diagram was used to show the interaction between polymer (CA/PBS), solvents (DMF or DMSO) and isopropanol as non-solvent by measuring the cloud point instead of Hansen solubility parameter differences. The effect of Polyethylene Gycol (PEG) to the membrane performance was also investigated. Morphology and tensile strength were analyzed by using Scanning Electron Microscopy (SEM) and Dynamic Mechanical Analysis (DMA), respectively. Experimental results proved that DMSO could be used to replace (DMF) as solvent, as the membranes had a higher value of salt rejection (84.9%). With the addition of PEG, salt rejection, mechanical property, and porosity of CA/PBS membrane also increases. The best result shows that PEG with concentration of 7% wt of polymer, the salt rejection is 88.89%; Permeate Flux is 29.036 L/m 2 .hr; tensile strength is 68.366 kPa; porosity is 75.16 % and the morphology is sponge-like with the pore size diameter in average is 0.262 µm