Sintesis Nanokomposit Lempung Bentonit-salisiltat dengan Metode Sol-Gel dan Karakterisasinya dengan XRD dan IR-FTIR

Synthesis of bentonite clay-salicylic acid nanocomposite with sol gel method by intercalation mechanism has been carried out in this research . In this intercalation process, salicylic acid should fit into the space between the layers of clay therefore salicylic acid must be made in the form of complex with the ion Fe (III). In the first stage of intercalation process, the concentration of intercalated was varied to achieve the best physico-chemical characterisc of the nanocomposite. The physico-chemical properties of bentonite clay nanocomposite-salicylic acid were characterized using X-ray diffraction (XRD), FTIR. Analysis of the XRD data showed that variations in the concentration of intercalated did not significantly change crystallinity. All of the composite formed showed the same diffractogram peak with the initial bentonite. Intercalation of salicylic acid into the space between the bentonite clay layers caused the distance between layers (d basal spacing) increased to 16-17Å. Analysis of spectra infrared (IR) showed several characteristic absorption band of clay and its modification. Absorption band at wave number 3620 cm-1 assigned for stretching vibration of OH to Al-OH on montmorillonite, band at 1640 cm-1 indicated the presence of OH bending from water adsorbed. Infrared spectra of three nanocomposite formed band at 1640 cm-1 shifted to lower wave number at 1631.78 cm-1 (a) 1635.64 cm-1 (b) and 1633.7 cm -1 (c) respectively. Absorption band at wave number 1115 cm-1 indicated the Si-O stretching the silicate layers and all of the nanocomposite obtained shifted the Si-O stretching silicate layers to 1109.7 cm-1 (a), 1111cm-1 (b and c) respectively. The adsorbtion at wavenumber 1633.71 cm-1, 1631.78 cm-1 and 1635 cm-1 showed the vibration of C = O groups derived from salicylic acid. Absorption band at wave number 920 cm-1 indicated the bending vibration of the Al-Al-OH. Keywords: nanocomposite, bentonite, salicylic acid