UTILIZATION OF TiO2-DOPED ACTIVATED CARBON FROM TEAK WOOD SAWDUST FOR PURIFICATION OF USED COOKING OIL Noni Novianti, Irfan Khadam, Mulda Muldarisnur*
Department of Physics, Andalas University, West Sumatra, Indonesia
Abstract
The intensive application of cooking oil poses environmental issues and health concerns. Research has been conducted to reduce of free fatty acids, water content, density, pH, viscosity, and refractive index of used cooking oil using TiO2-doped activated carbon produced from teak wood sawdust. Carbon was activated using a 10% ZnCl₂- solution before water and ash content measurements. Doping was carried out via solid-state synthesis with TiO₂-:activated carbon mass ratios of 9:100, 14:100, 18:100, and 22:100. The doped activated carbon underwent XRD characterization. Used oil was tested for water content, free fatty acids, pH, density, refractive index, viscosity, and clarity using UV-vis spectroscopy and FTIR. Activated carbon showed 3.60% water and 0.69% ash content. XRD results indicated a reduction in crystal size from 38.89 nm to 26.8 nm after TiO₂- doping. In treated oil, water content decreased from 0.38% to 0.15%, viscosity from 38 cP to 32 cP, refractive index from 1.69 to 1.5, density from 0.6613 to 0.588, and free fatty acids from 1.39% to 0.15%. UV-vis absorbance dropped from 3.06 to 2.88. The 14:100 mass ratio showed the best performance, indicating that TiO₂--doped activated carbon is an effective adsorbent to restore the quality of used cooking oil.
Keywords: Used cooking oil, activated carbon, TiO2, Purification, adsorbent
