The Preparation and Characterization of Silica Composite Adsorbent from Palm Oil Boiler Ash and Chitosan

Therecia Ginting (Kimia)
Agus Kembaren

Indonesian Journal of Chemical Science and Technology
Vol. 9 No. 2 (2026): JULY 2026

FTIR characterization of silica confirmed the presence of hydroxyl groups (-OH) at wave number 3386 cm-1. Wave number 1059 cm-1 Si-O-Si group, 783 cm-1, 984 cm-1 symmetric stretching vibration of Si-O-Si group, wave 452 cm-1 Siloxane group, in silica chitosan composite wide absorption band at 3356 cm-1 (-OH) group from silanol group (Si-OH) which is a functional group derived from silica as well as (-OH) and (-NH2) groups, 1628 cm-1 amide group (-NH) wave 1421 cm-1 related to symmetric bending vibration of chitosan oligosaccharide chain namely –CH2 and –CH3 groups which can be influenced by the presence of silica matrix 1079 cm-1 Si-O-Si group, wave 593 cm-1 and 488 cm-1 bending vibration of Si-O-Si and Si-O. The optimum result of Pb2+ adsorption using silica chitosan composite adsorbent was 94.70% with an absorption capacity of 1.2467 mg/g. With a concentration of 5.266 ppm it became 0.279 ppm.