Synthesis of microporous fluorinated chromia with a sharp pore distribution

This paper reports a novel micro-porous fluorinated chromia with a sharp pore distribution from 0.5 nm to 1.5 nm. The mentioned fluorinated chromia has a 105.1 m² g^-1 surface area and an excellent chemical stability in the presence of strong corrosive media such as HF, HCl and thermo-stability under 300 °C. A facile process for preparing the target material is carried out by controlling the decomposition rate of urea in a solution of chromium chloride to obtain its precursor, chromia, which has a narrow pore distribution in the range from 0.5 nm to 1.5 nm. Then the chromia is treated with HF via vapor-phase fluorination to obtain porous fluorinated chromia. The prepared material has been used as a fluorination catalyst with a high catalytic activity, and could be a potential membrane material and sorption media.