ADSORPSI DAN DESORPSI METILEN BIRU PADA MEMBRAN POLIELEKTROLIT KOMPLEKS KITOSAN-PEKTIN TERTAUT SILANG GLUTARALDEHIDA; ADSORPTION AND DESORPTION OF METHYLENE BLUE ON THE POLYELECTROLITE COMPLEX MEMBRANE OF CHITOSAN-PECTIN CROSSLINKED USING GLUTARALDEHYDE

Friska Septiani Silitonga, Dwi Siswanta

2014 | Disertasi | PROGRAM STUDI S2 ILMU KIMIA

A study of adsorption and desorption of methylene blue on the PEC membrane of chitosan-pectin crosslinked with glutaraldehyde has been conducted in order to determine the effect of glutaraldehyde on the membrane stability at pH below 5 . This study begins by synthesis of PEC membrane crosslinked with glutaraldehyde by dissolving pectin in distilled water and chitosan in acetic acid, and glutaraldehyde was added and evaporated at 70 °C. Characterization of the membrane was done by FTIR, water absorption, medium acidity, and Scanning Electrone Microscop (SEM). The effect of time, pH, concentration of methylene blue, the adsorption and desorption kinetics, and the adsorption isoterm also was studied. The results of FTIR spectra showed that the PEC membrane of chitosan-pectin appeared at 1604.77 cm-1. The PEC membrane with composition chitosan: pectin with crosslinked 10% GLA ( a mole ratio of chitosan) has the ability to absorb maximum water and stability of membrane at pH 3. The optimum condition of methylene blue adsorpstion occurs at pH 6 with a concentration of 100 mg L-1 with a time of 40 minutes of the membrane with a composition of 70:30 (10% GLA) and 80:20 (10% GLA), while the membrane with composition of 90:10 (10% GLA) at 30 minutes. Adsorption kinetics followed the pseudo second order kinetics with Langmuir isotherm. The maximum adsorption capacity is 108.7 mg g-1 and the equilibrium constant (K) of 1.42×104 L mol-1. Desorption kinetics followed the pseudo second order kinetics with rate constant (k) of 1.6×10-3 mg g-1 using NaCl 1 M.

Kata Kunci : PEC membrane crosslinked glutaraldehyde, methylene blue,kinetics adsorption-desorption