Synthesis of titanium dioxide nanoparticles using a continuous reaction method

TiO2 nanoparticles were synthesized from the hydrolysis and condensation of TEOT and vaporized water by using a continuous aging tube reactor. A new preparation method of nanoparticles was introduced, which consisted of a small reactor for controlling the hydrolysis rate and aging tube for decreasing the size of TiO2 particles. In this work, it was found that the particle size of TiO2 decreased with increasing reaction temperature, mole ratio (H2O/TEOT), and residence time. However, the particle size increased with increasing the diameter of aging tube. In addition, the optimal synthesis conditions were as follows; residence time in reactor (440 s) and aging tube (60 min), reaction temperature (42.5 °C), aging tube diameter (1.5 mm), mole ratio (80), and flow type in aging tube (intermittent type). The above-mentioned optimal conditions were used to obtain the particles with minimum particle size (<40 nm) and its standard deviation (<±5%), simultaneously.