Effect of acid on the crystalline phase of TiO2 prepared by hydrothermal treatment and its application in the oxidative steam reforming of methanol

Titania (TiO2) supports with anatase (A), mixed, and rutile (R) crystalline phases were prepared via the hydrothermal treatment of titanium isopropoxide and investigated as a catalyst for the oxidative steam reforming of methanol (OSRM). The different TiO2 phases were synthesized using different types of acid: acetic (HAc), nitric, and a mixture of HAc and hydrochloric acids, and hydrothermal (90 or 200 °C) or calcination (560 or 750 °C) temperatures. X-ray diffraction analysis revealed the crystal structure of successfully synthesized TiO2 with different TiO2-A:TiO2-R ratios. The TiO2-R with (110) and (101) planes showed the highest catalytic activity for OSRM in the temperature range of 200–400 °C.