Germanium recovery from gasification fly ash: evaluation of end-products obtained by precipitation methods

J Hazard Mater. 2009 Aug 15;167(1-3):582-8. doi: 10.1016/j.jhazmat.2009.01.021. Epub 2009 Jan 16.

Abstract

In this study the purity of the germanium end-products obtained by two different precipitation methods carried out on germanium-bearing solutions was evaluated as a last step of a hydrometallurgy process for the recovery of this valuable element from the Puertollano Integrated Gasification Combined Cycle (IGCC) fly ash. Since H(2)S is produced as a by-product in the gas cleaning system of the Puertollano IGCC plant, precipitation of germanium as GeS(2) was tested by sulfiding the Ge-bearing solutions. The technological and hazardous issues that surround H(2)S handling conducted to investigate a novel precipitation procedure: precipitation as an organic complex by adding 1,2-dihydroxy benzene pyrocatechol (CAT) and cetyltrimethylammonium bromide (CTAB) to the Ge-bearing solutions. Relatively high purity Ge end-products (90 and 93% hexagonal-GeO(2) purity, respectively) were obtained by precipitating Ge from enriched solutions, as GeS(2) sulfiding the solutions with H(2)S, or as organic complex with CAT/CTAB mixtures and subsequent roasting of the precipitates. Both methods showed high efficiency (>99%) to precipitate selectively Ge using a single precipitation stage from germanium-bearing solutions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Carbon / chemistry*
  • Catechols / chemistry
  • Cetrimonium
  • Cetrimonium Compounds / chemistry
  • Chemical Precipitation
  • Coal Ash
  • Conservation of Natural Resources / methods*
  • Germanium / isolation & purification*
  • Hydrogen Sulfide / chemistry
  • Industrial Waste
  • Metallurgy
  • Particulate Matter / chemistry*
  • Solutions

Substances

  • Catechols
  • Cetrimonium Compounds
  • Coal Ash
  • Industrial Waste
  • Particulate Matter
  • Solutions
  • Germanium
  • Carbon
  • Hydrogen Sulfide
  • Cetrimonium