Microbial selenium sulfide reduction for selenium recovery from wastewater

S.P.W. Hageman*, R.D. van der Weijden, A.J.M. Stams, P. van Cappellen, C.J.N. Buisman

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

12 Citations (Scopus)

Abstract

Microbial reduction of selenium sulfide (SeS2) is a key step in a new treatment process to recover selenium from selenate and selenite streams. In this process, selenate is first reduced to selenite, and subsequently selenite is reduced by sulfide and precipitates from the solution as SeS2. The latter is bio-reduced to elemental selenium and sulfide. Two anaerobic granular sludges (Eerbeek and Emmtec) were tested for their efficiency to reduce commercial crystalline SeS2. Emmtec sludge had the highest reducing capacity with commercial SeS2 and was therefore also used for the bioreduction of laboratory synthesized amorphous SeS2. Synthesized SeS2 was formed mixing a sulfide solution and effluent containing selenite. With both SeS2 solids (commercial and synthesized SeS2), Emmtec sludge produced sulfide and a solid consisting of hexagonal elemental selenium. The crystalline hexagonal structure suggests the absence of biomolecules, which stabilize amorphous selenium bio-particles under comparable process conditions (T = 30 °C and a pH between 6 and 7). Selenium particles were not attached to the biomass, suggesting an extracellular formation. The results support the feasibility of the bio-reduction process using sulfur for recovering selenium from water.
Original languageEnglish
Pages (from-to)110-119
JournalJournal of Hazardous Materials
Volume329
DOIs
Publication statusPublished - 2017

Keywords

  • Biocrystallization
  • Microbial reduction
  • Selenium removal and recovery
  • Selenium sulfide
  • Wastewater

Fingerprint Dive into the research topics of 'Microbial selenium sulfide reduction for selenium recovery from wastewater'. Together they form a unique fingerprint.

  • Cite this