Process for reclaiming a contaminated electrolyte from an electrolytic cell used in the production of gaseous fluorine

Abstract

A process for reclaiming a contaminated electrolyte in an electrolytic cell used in the production of gaseous fluorine. The contaminated electrolyte is a mixture of potassium bifluoride and hydrofluoric acid having metal ions therein. The process has the following steps: a) removing the contaminated electrolyte from the cell to a treatment tank; b) adding a lithium compound to the contaminated electrolyte in the treatment tank to induce settlement of at least part of the metal ions; c) allowing the metal ions to settle to the bottom of the treatment tank; d) removing the settled metal ions from the bottom of the treatment tank to form a reclaimed electrolyte; and e) returning the reclaimed electrolyte to the cell.

Description

technical field [0001] The present invention relates to a method of reclaiming electrolyte from electrolytic cells used for the production of gaseous fluorine. Background technique [0002] Gaseous fluorine (F 2 ) is produced by hydrofluoric acid (HF) cracking (hydrogen (H 2 ) as another product). The lysis takes place in the electrolytic cell. Each electrolytic cell typically contains potassium bifluoride (KHF 2 ) and HF mixture, often referred to as "melt (melt)". Electricity is passed through the liquid electrolyte to generate products. [0003] During cell operation, metal components in the cell body and head corrode over time to form ions that dissolve and / or become suspended in the melt. The most common is iron ions. When the metal ion content in the electrolyte reaches about 1% by weight (based on the total weight of the electrolyte), the performance of the electrolytic cell begins to deteriorate. At 2%, performance deteriorates to the point where the electrol...