APT Preparing Fluorinated Catalyst

Fluorination catalyst plays a central role in the reaction of gas phase catalytic fluorinated halogenated olefins, a method that using ammonium paratungstate (APT) and chromium hydroxide to prepare fluorination catalyst is proposed in this paper.



Steps like bellows:
1. Mixing the chromium hydroxide and APT a certain mass percentage, and pressing to obtain the precursor of product;
2. Calcining the catalyst precursor obtained in step 1 in the nitrogen atmosphere at 300℃~500℃ for 6~15 hours. In the calcination, a large amount of volatile compounds will be produced, and mainly is ammonia, making catalyst of high surface area, pore volume, thus enhancing the activity of catalyst;
3. Carrying out activation in the atmosphere of hydrogen fluoride and hydrogen (mixed gas mixed at a molar ratio of 10:1) at the temperature of 200℃~ 400℃ for 6 ~15 hours; in this process, all or part of the tungsten 6 will be reduced to tungsten;
4. Carrying out activation at 200℃~400℃ again, the atmosphere should be the mixed gas of hydrogen fluoride and chlorine at molar ratio of 10:1, for 6~15 hours, thus to get fluorination catalyst.