Research on Freeze Drying and High-temperature Molding in Medium-temperature Fluorocarbon Board

Abstract

A research and test system for the carbon anode plate preparation technology was established to optimize the physical and chemical indicators of carbon anode plates, such as bulk density, resistivity, and compressive strength, and improve the operating cycle. In this study, a carbon plate was prepared via a combination of high-temperature molding and freeze drying using a formulation with asphalt content much lower than the industry standard. The experimental results show that the density of the carbon plate is increased by 0.02–0.04 g/cm³ by improving the drying method. The carbon plate prepared in the laboratory has a bulk density of 1.814 g/cm³, resistivity of 29.8 µΩ·m, and compressive strength of 89.27 MPa. The bulk density, room-temperature resistivity, compressive strength, graphitization, and other key indices of the carbon plates made in the laboratory and those procured from a factory in Shanxi, Datong, were tested. Additionally, the specimens were analyzed using thermogravimetry-differential scanning calorimetry, scanning electron microscopy, and X-ray fluorescence. The laboratory-made carbon plates were superior to the factory specimens in terms of all the indicators tested. The process in this study improves the performance of the carbon anode plate and is used to provide technical support for electrolytic fluorine production in enterprises. The carbon plates prepared in the laboratory fully meet the process requirements of a medium-temperature electrolytic fluorine production line, which indicates the possibility of its use in the stable production of fluorine gas.

Keywords

fluorocarbon anode / high density / freeze drying / high-temperature molding

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