The method of producing red fluorescent powder from waste fluorescent powder

• Main Authors: TSO, CHING-YU, LEE, CHING-HWA, CHEN, JUNN, CHENG, MINGIN, CHEN, YU-JUEI, SHY, HSIOU-JENG, PAN, ZI-YU
• Format: Patent
• Language: Chinese; English
• Published: 01.11.2016
• Subjects: ADHESIVES; CHEMISTRY; CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATERTREATMENT OR WASTE MANAGEMENT; DISPOSAL OF SOLID WASTE; DYES; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FORELSEWHERE; METALLURGY; MISCELLANEOUS APPLICATIONS OF MATERIALS; MISCELLANEOUS COMPOSITIONS; NATURAL RESINS; PAINTS; PERFORMING OPERATIONS; POLISHES; RECLAMATION OF CONTAMINED SOIL SOIL; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE; TRANSPORTING

The present invention provides a method of producing red fluorescent powder from waste fluorescent powder, which comprises the following steps: (A) adding a first impregnating agent into waste fluorescent powder to form a first impregnating solution, impregnating the first impregnating solution at a first preset temperature for a first preset time, and filtering the first impregnating solution to obtain a first filter residue and a first filter solution containing europium, yttrium, and aluminum; (B) adding a first alkaline solution into the first filter solution containing europium, yttrium, and aluminum to obtain a first sodium-containing europium, yttrium precipitation compound; (C) washing the first sodium-containing europium, yttrium precipitation compound with hot water to remove sodium on the surface and obtain a first europium, yttrium precipitation compound; (D) baking and drying the first europium, yttrium precipitation compound at a second preset temperature for a second preset time; (E) oxidizing