MODIFIKASI KAOLIN DENGAN CETILTRIMETILAMMONIUM BROMIDA DAN APLIKASINYA UNTUK ADSORPSI ANION Cr(VI) DAN ANION Mn(VII); MODIFICATION OF KAOLIN WITH CETYLTRIMETHYLAMMONIUM BROMIDE AND ITS APPLICATION FOR ADSORPTION OF Cr(VI) ANION AND Mn(VII) ANION

Khoerunnisa, Sutarno

2011 | Disertasi | PROGRAM STUDI S2 KIMIA

Modification of Tatakan kaolin using cetyltrimethylammonium bromide (CTAB) and its application for adsorption of Cr(VI) anion and Mn(VII) anion have been performed. Kaolin was rinsed with H2O2 and NaOH and was calcined at 500 oC for 5 h. Solid was mixed with CTAB and stired for 24 h at room temperature. Product kaolin-CTAB was then used as adsorbent for Cr(VI) anion and Mn(VII) anion in aqueous solution. The optimum adsorption condition was studied at various pH, contact time, and anion concentration. The product was characterized by Infrared Spectrometry (FTIR) and X-ray difrraction (XRD), whereas the adsorbed anions were measured by atomic adsorption spectroscopy (AAS). X-ray diffraction patterns of kaolin samples showed that rinsing and modification did not change the structure of kaolinite. The result showed that the optimum adsorption of Cr(VI) anion and Mn(VII) anion by kaolin-CTAB occurred at pH=1.5-2 and pH=8.5-9, respectively. The adsorption of Cr(VI) anion and Mn(VII) anion were well fitted by a pseudo-first order kinetics with the rate constants of 3.74x10-2 minute-1 for Cr(VI) anion and 8.40x10-3 minute-1 for Mn(VII) anion. Kaolin-CTAB had the higher adsorption capacity of Cr(VI) anion (26.93 mmol.kg-1) than that of Mn(VII) anion (21.92 mmol.kg-1).

Kata Kunci : kaolin, CTAB, adsorption, Cr(VI) anion, and Mn(VII) anion