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 …

DOI: 10.1016/J.HYDROMET.2017.11.006 Corpus ID: 104228627; Recovery of germanium from leach solutions of fly ash using solvent extraction with various extractants @article{Haghighi2018RecoveryOG, title={Recovery of germanium from leach solutions of fly ash using solvent extraction with various extractants}, author={Hossein Haghighi and …

In this article, a hydrometallurgical method for the selective recovery of germanium from fly ash (FA) has been tested at pilot plant scale. The pilot plant flowsheet comprised a first stage of water leaching of FA, and a subsequent selective recovery of the germanium from the leachate by solvent extraction method. The solvent extraction method was based …

Water-soluble germanium species (GeS 2, GeS and hexagonal-GeO 2) are generated during coal gasification and retained in fly ash.This fact together with the high market value of this element and the relatively high contents in the fly ashes of the Puertollano Integrated Gasification in Combined Cycle (IGCC) plant directed our …

Germanium form fly ash leachates and catechol forms a complex. Ge- complex can be retained on to conventional anionic resin (215.5 mg of Ge/g of resin. Elution was achieved with acid solutions in an ethanol matrix. ... The possibility of resin reutilization was checked and high germanium extraction yields (97.6–98.3%) were very high after ...

Recovery of germanium from real fly ash leachates by ion-exchange extraction - ScienceDirect. Minerals Engineering. Volume 24, Issue 1, January 2011, …

O/A =1/8, mass ratio of complexing agent to germanium 12-16, and at normal temperature,3-5 min.The optimum back extraction conditions are NaOH concentration 30%, O/A=2, and at normal temperature ...

The germanium is mainly extracted from fly ash of lignite burn, zinc smelter residues, germanium-bearing waste electrical and electronic equipment, etc [8], [9]. Since germanium used in the world industry largely depends on GRL, the rational development of GRL is an important guarantee for the safe supply of germanium [10], [11], [12].

non-dispersive extraction; germanium; fly ash; heavy metals Introduction Various forms of germanium have extensive applica-tions. It can be used in photodetectors (pure form), high refraction glass (as GeO 2), etc. Since the chemical purity of germanium is essential in its application, the recovery, separation, and purification of germanium is

The solvent extraction of germanium and some heavy metals by commercial tri-octyl/decyl amine (Alamine 336), N-methyl-N, N-dioctyl chloride (Aliquat 336) and phosphine oxide (Cyanex 923) has been studied.In each extraction system, germanium was only extracted from a solution containing nickel, cadmium, cobalt, and zinc, which …

The research on the extraction of germanium with Exploration" process [37]. Furthermore, this precipitation method water from the Puertollano IGCC fly ash [25] revealed that relatively may give a high isolation potential for germanium from the impu- high extraction yields (up to 86%) were obtained using pure water. ... extraction of germanium ...

The results revealed that relatively high Ge extraction yields (up to 83 % after 2 h leaching period) may be achieved using a weak acid solution. Gallium yielded up to 70 and 64 % …

Fortunately, the above mentioned pilot plant was able to successfully extract Ga from fly ash, which is a big step forward in the process industrialization. 4.5. Electronics industry waste4.5.1. GaAs new scrap. ... Extraction of gallium and germanium from zinc refinery residues by pressure acid leaching. Hydrometallurgy, 164 (2016), pp. 313-320.

extraction11,12 and sorption onto chelating exchange resins.13,14 The SX method for the recovery of germanium from fly ash is based on the germanium-catechol (C 6O 2H 6) chelate and the subsequent extraction of the complex using tri-n-octylamine ((C 8H 17) 3N) and stripping with alkaline solutions. The equilibrium extraction

The process is based on hydrometallurgical operations: firstly a germanium extraction from fly ash by leaching and a consequent Ge separation from the other elements present in the solution by ...

During the germanium extraction with bis(2,4,4-trimethylpentyl)dithiophosphinic acid (Cyanex 301, HR), a significant increase in the germanium extraction is due to the formation of a cationic ...

Germanium, a scattered metal in nature, is generally extracted from coal fly ash produced by the combustion of germanium-rich lignite in industrial process. It is a direct approach for germanium enrichment from lignite, however facing the challenges of high carbon emission and losing valuable humic acid.

Under a comparable Cyanex 923 condition, the germanium extraction efficiency by the aforementioned extractants was in the order Aliquat Fly ashes 336 > Alamine 336 > Cyanex 923. The slope analysis method showed that 2 moles of Alamine 336 and Aliquat 336, as well as 4 moles of Cyanex 923, participated in the extraction of germanium.

Germanium and gallium occur as water soluble Ge (hexagonal-GeO2 and GeS2) and Ga oxide species in relatively high contents in the Puertollano Integrated Gasification with Combined Cycle (IGCC) fly ash. Both the speciation and contents of Ge and Ga in this cogasification (50:50 coal/pet-coke) fly ash, allowed starting research for developing …

The current research examined the extraction of germanium, vanadium, and lithium from coal fly ash (CFA) using a sequential sodium salt roasting and organic acid leaching process. To this end, three sets of experiments were performed. In all experiments, CFA was roasted with salt at 850 °C and then leached with an organic acid.

Germanium (Ge) as an important strategic metal is widely used in many modern-technology fields such as optical fiber and thermal solar cells. In this study, the volatilization behavior of Ge from low-grade germanium-bearing lignite was investigated in detail through reductive volatilization. The results indicated that temperature and air flow …

The research on the extraction of germanium with water from the Puertollano IGCC fly ash [25] revealed that relatively high extraction yields (up to 86%) were obtained using pure water. These promising results conducted research towards the study of enrichment and precipitation methods for Ge recovery, such as ion flotation [16,26], adsorption ...

Germanium and Ga extraction tests were carried out on Puertollano IGCC fly ash. The whole extraction conditions selected (Table 2) were applied on the historical IGCC FA samples. The results of these extraction tests allowed the selection of the optimal extractant(s) for Ge and/or Ga. Extraction tests with the optimal extractant were ...

The germanium – together with other metals and metalloids contained in the fly ash generated in the Integrated Gasification in Combined Cycle (IGCC) of Elcogas plant (Puertollano, Spain) – may be extracted by aqueous leaching. Here we report the study of the selective recovery of germanium from aqueous leachate by means of ion flotation, …

The germanium – together with other metals and metalloids contained in the fly ash generated in the Integrated Gasification in Combined Cycle (IGCC) of Elcogas plant (Puertollano, Spain) – may be extracted by aqueous leaching. Here we report the study of the selective recovery of germanium from aqueous leachate by means of ion flotation ...

Germanium in coal fly ash can be successfully recycled; simultaneously, GeAs ultrafine particles were prepared. Separation principle and feasibility of this process was discussed. Temperature,...

In this article, a hydrometallurgical method for the selective recovery of germanium from fly ash (FA) has been tested at pilot plant scale. The pilot plant flowsheet comprised a first stage of water leaching of FA, and a subsequent selective recovery of the germanium from the leachate by solvent extraction method. The solvent extraction …

Solvent extraction experiments were conducted from acidic solutions containing germanium(IV) and other metal ions, such as Ga 3+, Fe 3+, Zn 2+ and Fe 2+ in hydrometallurgical process of zinc. The purpose of this work was to enhance the efficiency of the extraction and stripping processes and the selectivity of germanium and other …

Germanium, a scattered metal in nature, is generally extracted from coal fly ash produced by the combustion of germanium-rich lignite in industrial process. It is a direct approach for germanium enrichment from lignite, however facing the challenges of high carbon emission and losing valuable humic acid.

Flotation of Germanium from Dilute Solutions. Abstract In laboratory experiments, ion flotation was found effective as a concentration method for germanium from dilute aqueous solutions. Removals over 90% were obtained at neutral pH conditions….

As discussed in Section 2.1, byproducts of zinc metallurgy, fly ash of lignite, and optical fiber could be used as sources for germanium recovery; germanium feed …

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.

The order of reagent concentration efficiency in term of maximum extraction is 2.5 ≥ 5>7.5 M. This shows that there is a H + and CH 3 COOH − concentration beyond which germanium extraction decreases. Therefore, the best reagent concentration for maximum germanium extraction was maintained to be 2.5 M for other experiments.

Germanium recovery from real fly ash (FA) leachates was studied using ion-exchange procedures. The procedure was based on germanium complexation with catechol () in an aqueous solution followed ...

This article is concerned with a simple hydrometallurgical method for the selective recovery of germanium from fly ash (FA) generated in an integrated gasification with combined cycle (IGCC) process. The method is based on the leaching of FA with water and a subsequent concentration and selective separation of germanium by a solvent …

Recovery of germanium from leach solutions of fly ash using solvent extraction with various extractants Hossein Kamran Haghighi The solvent extraction of germanium and some heavy metals by commercial tri-octyl/decyl amine (Alamine 336), N-methyl-N, N-dioctyl chloride (Aliquat 336) and phosphine oxide (Cyanex 923) has been studied.