SYNTHESIS OF CHITOSAN MEMBRANES AND ITS APPLICATION IN THE ADSORPTION OF Pb2+ ION IN SOLUTION

Heavy metals are pollutants that cannot be decomposed in the environment, so they have to be removed from the environment by membrane adsorption techniques. The study aims to: (1) synthesize chitosan from rice field snail shells, (2) synthesize and characterize chitosan membranes with varying concentrations of chitosan, and (3) determine the pH and contact time optimum to adsorb Pb2+ ions in solution. Production of chitosan powder from rice field snail shells through deproteination, demineralization, depigmentation, and deacetylation. Furthermore, it was characterized in the yield, color, molecular weight, degree of polymerization, degree of deacetylation, and functional groups. Synthesis of chitosan membrane was carried out by varying the mass of chitosan. The characterization included measurement of membrane thickness, swelling test, SEM, and FTIR test. The results obtained show that (1) the synthesis of chitosan from rice field snail shells produces chitosan with a 5% yield, brownish-white color, odorless, the number of chitosan molecules was 1.0655 x 106 Da, degree of deacetylation is 80.73%. (2) the best concentration of chitosan in the synthesis of chitosan membrane is 3% with a thickness of 0.0123 mm and the highest swelling ability, (3) a maximum contact time was 120 minutes to absorb Pb (II) ions of 91.496% and pH 5 is the optimum pH with an absorption percentage of 98.919%.