METHOD FOR SEPARATING SILICON AND SILICON CARBIDE FROM THE DISPOSED SLUDGE PRODUCED IN THE PROCESS OF SILICON WAFER

摘要

PURPOSE: A method for separating silicon and silicon carbide from waste sludge generated from a silicon wafer manufacturing process is provided to effectively implement a separating process using the specific gravity difference of the silicon and the silicon carbide. CONSTITUTION: The liquid part of waste sludge is dissolved in an organic solvent. The resultant is first centrifuged to be separated into a liquid part and a solid part. The solid part is treated with an acid solution in order to minimize the contents of organic materials, metals, and impurities. A heavy-liquid solution is mixed with the acid solution treated solution and is centrifuged a second time. The acid solution is based on one or more selected from a group including sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid, or a mixture of the same.