Removal of CrO42-, a Nonradioactive Surrogate of 99TcO4-, Using LDH-Mo3S13Nanosheets

Celik A., Li D., Quintero M. A., Taylor-Pashow K. M. L., Zhu X., Shakouri M., ...More

Environmental Science and Technology, vol.56, no.12, pp.8590-8598, 2022 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 56 Issue: 12
  • Publication Date: 2022
  • Doi Number: 10.1021/acs.est.1c08766
  • Journal Name: Environmental Science and Technology
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, ABI/INFORM, Applied Science & Technology Source, Aqualine, Aquatic Science & Fisheries Abstracts (ASFA), Artic & Antarctic Regions, BIOSIS, Biotechnology Research Abstracts, Business Source Elite, Business Source Premier, CAB Abstracts, Chemical Abstracts Core, Chimica, Compendex, Computer & Applied Sciences, EMBASE, Environment Index, Food Science & Technology Abstracts, Geobase, Greenfile, MEDLINE, Pollution Abstracts, Public Affairs Index, Veterinary Science Database, DIALNET
  • Page Numbers: pp.8590-8598
  • Keywords: chromate, Hanford's radioactive waste, low activity waste, nuclear waste, off-gas condensate stream, pertechnetate
  • Ankara Yıldırım Beyazıt University Affiliated: Yes

Abstract

Removal of chromate (CrO42-) and pertechnetate (TcO4-) from the Hanford Low Activity Waste (LAW) is beneficial as it impacts the cost, life cycle, operational complexity of the Waste Treatment and Immobilization Plant (WTP), and integrity of vitrified glass for nuclear waste disposal. Here, we report the application of [MoIV3S13]2-intercalated layer double hydroxides (LDH-Mo3S13) for the removal of CrO42-as a surrogate for TcO4-, from ppm to ppb levels from water and a simulated LAW off-gas condensate of Hanford's WTP. LDH-Mo3S13removes CrO42-from the LAW condensate stream, having a pH of 7.5, from ppm (∼9.086 × 104ppb of Cr6+) to below 1 ppb levels with distribution constant (Kd) values of up to ∼107mL/g. Analysis of postadsorbed solids indicates that CrO42-removal mainly proceeds by reduction of Cr6+to Cr3+. This study sets the first example of a metal sulfide intercalated LDH for the removal of CrO42-, as relevant to TcO4-, from the simulated off-gas condensate streams of Hanford's LAW melter which contains highly concentrated competitive anions, namely F-, Cl-, CO32-, NO3-, BO33-, NO2-, SO42-, and B4O72-. LDH-Mo3S13's remarkable removal efficiency makes it a promising sorbent to remediate CrO42-/TcO4-from surface water and an off-gas condensate of nuclear waste.