MODIFIED SILICA BIS-APTES WITH OCTANOIC ACID AND ALKYL ALCOHOL OXIDATION PRODUCT

• Main Author: Widyaningsih, Monica
• Format: Final Project
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/62690
• Institution: Institut Teknologi Bandung

Indonesia is the largest producer of CPO (Crude Palm Oil) in the world. The oleic acid contained in CPO has the potential to be used in modifying silica amines to increase the selling value of CPO. In this research, oleic acid has been successfully synthesized by oxidation of the alcohol “rophanol 90/95v” using K2Cr2O7. The formation of oleic acid was indicated by the loss of the absorption peak at 3.6 ppm on the 1H NMR characterization which indicated that the CH2 bound to the hydroxyl group (-OH) had changed to the carbonyl functional group. The silica modification process in this study was carried out using Bis-APTES as a precursor, toluene as a solvent, and ammonia as a catalyst with a volume ratio of 80: 15: 5. The silica formed was then adidated with oleic acid and octanoic acid using DCC reagent coupling and DMAP catalyst. The FTIR spectrum of silica oleate shows a peak at 1028 cm-1 and 1114 cm-1 caused by the Si-O-Si strain, a peak at 820 cm-1 which is the peak of the Si-C strain, and a peak at 2900 cm-1 which is the peak of the CH strain. The TEM results show that Bis-APTES silica and oleic silica have irregular morphology. Modification of amine silica with octanoic acid in this study is intended as a comparison of oleic silica. The FTIR spectrum of silica octanoate also shows peaks at wave numbers of 1028 cm-1 and 1114 cm-1 caused by the Si-O- Si strain, a peak at 820 cm-1 which is the peak of the Si-C strain, and a peak at 2900 cm-1 which is the peak of the CH strain. In the FTIR spectrum of silica oleate and silica octanoate, there is no visible peak in the 1750 cm-1 region which is the peak of the C=O strain. This is probably because the amount of fatty acids attached to the silica is much less when compared to the large size of the silica. The TEM results show that silica octanoate also has an irregular morphology. The contact test of silica octanoate with caffeine showed the presence of adsorption which was indicated by the caffeine concentration which was reduced from 100 ppm to 95 ppm, while the contact of Bis-APTES silica with caffeine did not show any adsorption. The presence of adsorption indicates that silica modified with fatty acids has the potential to become an adsorbent for non-polar compounds.