Biotransformation of lanthanum by Aspergillus niger

Xia Kang, Laszlo Csetenyi, Geoffrey Gadd (Lead / Corresponding author)

Research output: Contribution to journalArticle

6 Citations (Scopus)
168 Downloads (Pure)

Abstract

Lanthanum is an important rare earth element and has many applications in modern electronics and catalyst manufacturing. However, there exist several obstacles in the recovery and cycling of this element due to a low average grade in exploitable deposits and low recovery rates by energy-intensive extraction procedures. In this work, a novel method to transform and recover La has been proposed using the geoactive properties of Aspergillus niger. La-containing crystals were formed and collected after A. niger was grown on Czapek-Dox agar medium amended with LaCl 3. Energy-dispersive X-ray analysis (EDXA) showed the crystals contained C, O, and La; scanning electron microscopy revealed that the crystals were of a tabular structure with terraced surfaces. X-ray diffraction identified the mineral phase of the sample as La 2(C 2O 4) 3·10H 2O. Thermogravimetric analysis transformed the oxalate crystals into La 2O 3 with the kinetics of thermal decomposition corresponding well with theoretical calculations. Geochemical modelling further confirmed that the crystals were lanthanum decahydrate and identified optimal conditions for their precipitation. To quantify crystal production, biomass-free fungal culture supernatants were used to precipitate La. The results showed that the precipitated lanthanum decahydrate achieved optimal yields when the concentration of La was above 15 mM and that 100% La was removed from the system at 5 mM La. Our findings provide a new aspect in the biotransformation and biorecovery of rare earth elements from solution using biomass-free fungal culture systems.

Original languageEnglish
Pages (from-to)981-993
Number of pages13
JournalApplied Microbiology and Biotechnology
Volume103
Issue number2
Early online date15 Nov 2018
DOIs
Publication statusPublished - Jan 2019

Keywords

  • Aspergillus niger
  • Biorecovery
  • Biotransformation
  • Lanthanum
  • Rare earth elements

Fingerprint Dive into the research topics of 'Biotransformation of lanthanum by Aspergillus niger'. Together they form a unique fingerprint.

  • Cite this