Optical glass is the raw material for optical lens, which is used for optical equipment such as camera or facsimile. It includes a large quantity of rare earth elements for improving its optical characteristics. Therefore, because of its composition, the wastes of optical glass have a high value of resources. However, their recycling is considered to be a difficult process.
In this study, recovery of rare earth from two types of optical glass wastes (sample A and sample B) was investigated by means of alkali fusion and oxalate precipitation for sample A ,and alkali leach and solvent extraction for sample B.
Regarding to the experimental results of sample A, the grade of 83.4 % and the recovery of 71.1 % for lanthanum are achieved from waste optical glass by alkali fusion with an equivalent mixture of the fusing agent of sodium carbonate and potassium carbonate, and precipitation with ammonium oxalate.
Regarding to the experimental results of sample B, the distribution of 99.95 % La, 98.65 % Y and 95.18 % Gd from waste optical glass is achieved by alkali leaching followed by sodium hydroxide and solvent extraction with D2EHPA.
