Germanium: Current and Novel Recovery Processes

Abstract

Germanium (Ge) is considered a critical element due to its many industrial applications; Ge is a metalloid used in solar cells, fiber optics, metallurgy, chemotherapy, and polymerization catalysis. The main sources of Ge are sulfides ores of Zn, Pb, and Cu, coal deposits, as well as by-products and residues from the processing of these ores and coals (e.g., smelting flue dust and coal fly ashes). Indeed, over 30% of global Ge consumed come from recycling processes. The recovery of Ge from sulfide ores is mostly based on hydrometallurgical processes followed by a number of mass transfer techniques to concentrate Ge (e.g., solvent extraction). However, environmental-friendly extraction methods of Ge from coal fly ashes and copper smelting flue dust have recently been proposed in order to reduce environmental impacts. In addition, novel processes based on absorption of Ge with ribbon grass have become an interesting option not only to produce Ge but also to boost soil decontamination and biogas production. This chapter presents a general description of Ge occurrence, associations, and chemistry as well as a review of the current and novel recovery processes of Ge. The main sources of Ge and its main industrial applications are also discussed.

The effects of germanium and selenium on growth, metalloid accumulation and ergosterol content in mushrooms: experimental study in Pleurotus ostreatus and Ganoderma lucidum

“…It is known that tailings, e.g. those originating from zinc mining, can be characterized by increased levels of Ge [41]. Some mushroom species have already been shown to maintain their growth on highly contaminated soils polluted with flotation tailings [42].…”

Redistribution of germanium during dynamic recrystallization of sphalerite

“…Many rare metals are critical to the sustained development of 21 st century technologies; for example, germanium (Ge) is essential to optic-fiber systems used in military and civil telecommunications. The production of rare metals remains challenging, notably because only a few percent of the total rare metal content is recovered from base metal deposits (Ruiz et al, 2018;U.S. Geological Survey, 2019).…”

Behavior of critical metals in metamorphosed Pb-Zn ore deposits: example from the Pyrenean Axial Zone

“…Currently, the production of rare metals from base-metal deposits remains challenging. Germanium is generally extracted, for example, by hydrometallurgy followed by various mass transfer techniques (Ruiz et al 2018). However, only a few percent of the total rare metal content in sphalerite (at ppm level) is https://eproofing.springer.com/journals_v2/printpage.php?token=cf5RuMc0-xKPeshf3EG_BUsUunVWdllswv77Wh3JIII 5/47 recovered due to a negative effect which prevents the extraction of zinc (around 3% of the Ge extracted; Ruiz et al 2018;U.S.…”