Electrolysis of (CH3)4NF•5HF Melt with Boron-doped Diamond Anode

Abstract

Since a boron-doped diamond (BDD) electrode is able to be used as an anode in the (CH3)4NF•mHF melt, the performance of BDD anode for electrolytic production of perfluorotrimethylamine [(CF3)3N] was investigated in the melt of (CH3)4NF•5.0HF by galvanostatic electrolysis at 20, 40, 60 and 100 mA•cm−2. The anode gas was analyzed quantatively by gas chromatography-mass spectroscopy. Also, the surface of BDD electrode before and after electrolysis was analyzed by XRD and Raman spectroscopy and was observed by SEM. The ratios of (CF3)3N and (CF3)2CHF2N to overall anode gas increased with increasing the current density. This fact suggests that electrolytic fluorination may be promoted at higher current density. From the results of surface analyses, it is concluded that the electrolytic production of (CF3)3N from (CH3)4NF•5.0HF melt using a BDD anode is an appropriate process because the BDD film on the carbon substrate has a good electric conductivity during electrolysis.

Anodic Fluorination, Methoxylation, Acetoxylation, and Cyanation of Heteroatom Organic Compounds Using Boron‐Doped Diamond, GC, and Pt Electrodes

“…Regarding the durability of anode materials, it is known that Pt anodes dissolve into MeCN and methanol during anodic oxidation, [33] while BDD anodes are mechanically and chemically stable enough even after repeated use in these solvents. Mizuno also reported that BDD anode surface structure was maintained during electrolysis in Me 4 NF-5HF melt producing (CF 3 ) 3 N. 34…”