Analisis Penambahan Aseton dalam Bak Koagulasi pada Pembuatan Membran Selulosa Asetat Bacterial Cellulose Nanocrystals (CA-BCNCS)

Abstract

Bacterial Cellulose Nanocrystals (BCNCs) as porogen were used to improve performance of Cellulose Acetate (CA) membrane for ultrafiltration by increased hydrophilicity, pure water flux, and permeability properties. But for some reason, it can decrease membrane selectivity by decreasing rejection coefficient of feed solution. The influence of adding solvent in the coagulation bath can enhance CA membrane rejection coefficient by delayed solvent-nonsolvent demixing led to decreased pore membrane. Acetone was choosed as coagulation bath composition because it had small difference in solubility parameters with CA so it can increasing the affinity between CA and nonsolvent. Different loading of acetone (0-4%) in coagulation bath were studied. The membranes were prepared by non-solvent induced phase separation (NIPS) technique, and their physicochemical and performance properties were characterized by density, swelling, porosity, contact angel, pure water flux, permeability coefficient, and rejection coefficient. The membran with the addition of acetone 4% became more denser and its porosity decreased by 0,24962 g/cm3 and 50,9470% from membrane without acetone by 0,2397 g/cm3 and 55,9924%. It causing swelling and hydrophilicity membrane decreasing to by 204,0918% and 75˚ which leading to decreasing pure water flux and permeability membrane but increasing selectivity by the dextran rejection coefficient. Membrane with addition BCNCs and acetone in the coagulation bath showed increase in pure water flux and rejection dextran 500 kDa on the 3% CA BCNCs membrane by 11,679 L/m2.h dan 86,23%.