Method for producing germanium tetrachloride for optical fibre

Abstract

The invention discloses a method for producing germanium tetrachloride for optical fibers, which includes the steps: hydrochloric acid and germanium tetrachloride with a volume ratio of 0.25-2.0: 1 are added into a distiller to be distilled; or while separately distilling the germanium tetrachloride, HCI gas is pumped in until the distilling is finished with the distilling temperature of 76-80 DEG C; after the distilled solution is separated by a hydrochloric separator, the germanium tetrachloride solution is stored in a storage tank to be discharged to an empty tower distiller for 36-72 hours of standing; temperature of the germanium tetrachloride solution is raised to 70-75 DEG C; while continuous pumping nitrogen for 12-36 hours, an ultraviolet lamp is adopted for lighting; finally, distillation operation is carried out at 76-80 DEG C and the product is transferred. The method for producing the germanium tetrachloride for optical fibers has the advantages of simple process course and convenient operation which can remove the impurity containing hydrogen in the germanium tetrachloride with high value for industrial use.

Description

technical field [0001] The invention belongs to the field of rare metal metallurgy, and relates to a method for purifying high-purity compounds, in particular to a method for purifying germanium tetrachloride for optical fiber used in optical fiber production. Background technique [0002] High-purity germanium tetrachloride is an indispensable key raw material for high-grade quartz-based optical fibers. It is used as the main dopant in quartz-based optical fibers. Its purpose is to increase the refractive index of the optical fiber, reduce optical loss, and then increase the transmission distance of the optical fiber. Since the dopant enters the fiber core, its content and distribution determine the important performance indicators of the fiber, and its quality directly affects whether a high-quality fiber can be obtained. Therefore, the requirements for the content of metal impurities (Fe, Co, Cr, Mn, Cu, etc.) and hydrogen-containing impurities (OH, CH, HCl) in germanium ...

AI Technical Summary

Problems solved by technology

[0003] The currently widely used rectification process can remove metal impurities (Fe, Co, Cr, Mn, Cu, etc.) well, but cannot effectively remove hydrogen-containing impurities (OH, CH, HCl); hydrogen chloride gas alone or anhydrous Chlorine is used to purify germanium tetrachloride, which can only remove arsenic and other similar impurities, but not hydrogen-containing impurities; PCl 3 or PBr 3 Add to SiCl 4 , GeCl 4 and POCl 3 and adding Cl to it 2 or Br 2 , which reacts the -OH group to form HCl (or HBr) and POCl 3 (or POBr 3 ), and then remove HCl and HBr, thereby realizing the removal of OH impurity and HCl impurity in germanium tetrachloride, and this technology cannot remove CH impurity; Atoms are chlorinated into hydrogen chloride by chlorine gas, and finally the removal of hydrogen-containing impurities is achieved, but the process requires very high equipment and complicated operations