Titanium Dioxide as a Packing Material for Micro-Packed Column in Gas Chromatography

Abstract

A gas chromatographic micro-packed column prepared with titanium dioxide (TiO₂) particles was developed. This study reports the fundamental retention behavior of the column for several organic and inorganic gaseous compounds, and quantitatively analyzes the high-temperature degradation behavior of the injected organic compounds. The anatase TiO₂ particles were prepared by hydrolysis of titanium (IV) isopropoxide. The particle size was classified as 150 – 180 μm. The micro-packed column was prepared by packing the classified TiO₂ particles into a stainless steel capillary of inner diameter of 1.0 mm and length of 1.0 m. The TiO₂ micro-packed column was connected to a conventional gas chromatograph equipped with a flame ionization detector or a thermal conductivity detector. The column showed high retentivity for carbon dioxide and also for organic compounds, achieving a baseline separation of methane and ethane. The TiO₂ packed column was highly thermally stable, with a temperature limit above 400°C. Above 300°C, the analytes injected into the column were thermally degraded by catalytic combustion of TiO₂ under N₂ carrier gas. On the other hand, the degradation was obtained above 200°C using air as the carrier gas.