Separation of Cerium Oxide Abrasive from an Abrasive–Glass Polishing Powder Waste by Means of Liquid-Liquid Extraction Method

Abstract

Polishing glass components using a cerium oxide abrasive produces an abrasive–glass polishing powder waste. This study investigated the feasibility of applying the liquid-liquid extraction method for separating cerium oxide abrasive from an abrasive–glass polishing powder waste. Isooctane and water served as the two liquids, and sodium oleate (NaOL) served as the surfactant collector. First of all, the extracted fraction of individual cerium oxide abrasive and glass powder from the water phase to the isooctane phase was investigated separately. Subsequently, the cerium oxide abrasive was separated from an abrasive–glass powder mixture. The results indicated that the extracted fraction of the cerium oxide abrasive reached nearly 100% at a pH of 7 when more than 2.5 kg/ton of NaOL was added, whereas that of the glass powder was approximately 10%. Optimal separation of the cerium oxide abrasive from an abrasive–glass powder mixture was achieved at a pH of 7 with the addition of 7.5 kg/ton of NaOL; the grade of cerium oxide abrasive in the solid of isooctane phase reached 96.0%, with the recovery being 94.5%. After this method was applied to a real abrasive–glass polishing powder waste under optimal separation conditions, the grade and recovery of cerium oxide abrasive in the solid of isooctane phase reached 96.4% and 88.1%, respectively.