Optimization of fluorination of the tungsten powder with fluorine in a reactor with an immobile layer with the provision of green requirements

Abstract

The computational procedures to model the fluorination of the tungsten powder with fluorine and condensation of formed WF₆, which describe the available experimental data satisfactorily, are developed using physicochemical foundations of processes. With their help, the equipment sizes and process parameters of the two-stage fluorination of the tungsten powder with fluorine with the condensation of liquid WF₆ after each stage at 2.5–3.0°C are optimized. The possibility of fabricating WF₆ with productivity of 5.23, 6.53, and 7.83 kg/h in reactors 200, 300, and 360 mm in diameter, respectively, at 300–350°C without the forced cooling of the highest heat-beat first fluorination setup is shown. The completeness of fluorine usage higher than 99.99% is attained in this case, while the amount of harmful gases (F₂, WF₆) leaving the process chain does not exceed their maximal permissible concentrations already in the vent gas volume. Recommendations for the organization of the fluorination production process of the tungsten powder are given.