Abstract:Titanium dioxide (TiO₂) nano-particle is widely used in composite materials to its improved mechanical properties. TiO₂ nano-particle was used in the composite material that consists of palm oil sludge from the palm oil production and activated sludge cake from a papermaking process. TiO₂ was synthesized by a hydrolysis of titanium isopropoxide. The parameter was investigated by the mole ratio of reactant to different solvents (isopropanol and isobutanol). The solution was prepared by adjusting pH to acid solution, resulting in different sizes and distributions of precipitate which was heated at different temperatures. The obtained samples were then morphologically and structurally characterized using X-ray diffraction (XRD) and particle size distribution (PSD). The experimental results show that the TiO₂ sample from isopropanol solvent with heated temperature of 600 °C exhibits the best results. Consequently, different mass fractions of TiO₂ (0, 0.5%, 1.0%, 2.0%, 4.0% and 8.0%) were used for specimens that were made from palm oil sludge mixed with activated sludge cake. All samples were later characterized by 3-point bending test and compression test. The results indicate that the adding 0.5% and 1.0% TiO₂ particles to the composite material outperforms the other fractions in terms of enhancing mechanical properties. Nonetheless, mechanical properties tends to decrease when adding 2.0% TiO₂.

Key words: titanium dioxide; palm oil sludge; active sludge cake; composite; mechanical properties