SIFAT ADSORPSI DAN KARAKTERISTIK KITOSAN TERCETAK IONIK SENG DAN TEMBAGA

The synthesis of Imprinted Ionic Chitosan of Zinc (IIC-Zn), and Imprinted Ionic Chitosan of Copper (IIC-Cu) was started by complexing chitosan using metal ion Zn(II) and Cu(II) 3000 mg/L in acetic acid solution, then cross-linked them with glutaraldehyde, then the metal ion precursor was desorbed with Na2EDTA. The solid synthesis result was identified for its functional groups with FTIR method and its crystallinity using XRD method. The adsorption process of Zn(II) and Cu(II) was conducted using batch adsorption as a function of pH, contact time, and variety of Zn(II) and Cu(II) ion concentrations. The adsorption selectivity of adsorbent against mixture of Zn(II) and Cu(II) ion. The analysis of Zn(II) and Cu(II) ion before and after adsorption was done by using atomic absorption spectrometry (AAS). The results of desorption is known that the largest contribution to the mechanism was the complex formation.The result indicated that Zn(II) metal ion adsorption rate constant in IIC-Zn was k1=8.2x10-3 min-1 and crosslinking-chitosan (CC) was k1=4.8x10-3 min-1. In addition, Cu(II) metal ion adsorption rate constant in IIC-Cu was 2.6 x10-3 min-1 and CC was k1=9.0 x 10-4 min-1. As a result Zn(II) ion adsorption capacity based on Langmuir adsorption isotherm model in IIC-Zn was 89.27 mg/g and CC was 36.39 mg/g , and the total energy of adsorption in the range 22.73 kJ/mol for IIC-Zn and 26.72 kJ/mol for IIC-Cu(II). Ion adsorption capacity based on Langmuir adsorption isotherm model in IIC-Cu was 86.69 mg/g and CC was 51.05 mg/g, while Cu(II) ion adsorption capacity based on Freundlich adsorption isotherm model on IIC-Cu was 14.29 mg/g and on CC was 6.69 mg/g. while the total energy in the range 22.71 kJ / mol for IIC-Cu and 22.23 kJ / mol for CC. Relative selectivity analysis indicated that IIC-Zn has a high selectivity toward Zn(II) ion with selectivity coefficient (αZn/Cu =1.58), IIC-Cu has a low selectivity toward Cu(II) ion with selectivity coefficient of (αCu/Zn =1.22). Chemical stability studies showed that CC, IIC-Zn and IIC-Cu are more stable in acid medium than chitosan materials