Mechanism of Extracting Germanium from Ge-Containing Solution with Tannins

The process of germanium–tannin complex is the oldest form technology for extracting germanium from Ge-containing solutions. This reaction mechanism relatively controversial as it imposes restrictions on ideas and methods reducing amount tannin. In this paper, using SEM, TEM, FT-IR, XPS, NMR, TOF-SIMS UV diffuse reflectance spectroscopy a deep analysis complex, solutions with tannins investigated. results show that theoretical tannin mass 30 times mass, rate reaches 98.84%. changes -OH stretching band in FT-IR spectra, emergence C3H3GeO7, C2H3GeO6, C8H7GeO7 images, shift Ge O banding energy XPS detail spectra provided definitive evidence process, highlighting formed complexes involve six coordinate Ge-O bonds, which are obtained through orthophenol hydroxyl groups reacting Ge4+. Furthermore, mode germanium–tannins layer polymerization, finally forms an agglomeration flocs. findings research innovative, can have profound impact future introduction various to reduce tannins.