Concentration and treatment of ceric ammonium nitrate wastewater by integrated electrodialysis-vacuum membrane distillation process

Electrochemical approaches for selective recovery of critical elements in hydrometallurgical processes of complex feedstocks

“…Cerium tends to appear in the wastewater from ceric ammonium nitrate manufacturing. A hybrid method of using electrodialysis and vacuum membrane distillation was performed for the separation of cerium from nitrate ( Ren et al., 2018 ). In nitric acid bath, cerium ion exists in the form of an individual cerium ion (Ce 4+ ) or it forms Ce(NO 3 ) n (4−n)+ complexes, both of which can be rejected by typical anion exchange membrane owing to charge or large molecular diameter, respectively.…”

“…Increase in flow rate, current density, and nitric acid concentration all improved the removal of nitrate from the waste stream to the anodic compartment. The vacuum membrane distillation process concentrated the cerium solution and yielded a 99.9% rejection rate of cerium ( Table 5 ) ( Ren et al., 2018 ).…”

“…Ga was prepared in 100 mM NaCl Unaligned carbon nanotubes encapsulated in polyvinyl alcohol filters 86%–96% max recovery (except for As). Metals are recovered as oxides ( O'Connor et al., 2018 ) Redox-active functional electrode Y 0.1 M Y 3+ Aqueous Y 3+ ion imprinted ferricyanide-embedded polypyrrole film / ( Du et al., 2015 ) Electrodialysis/vacuum membrane distillation Ce 0.2 mM Ce 4+ Nitric acid Anion exchange membranes (ASV, QPPO, CJMA-3), vacuum membrane distillation (TJ [the PVDF hollow fiber membrane produced by Tianjin University of Technology], DH [the PVDF hollow fiber membrane produced by Dehong CO., Ltd., China]) 90% recovery efficiency of nitric acid at 0.1 mM for 6 h using CJMA-3 anion exchange membranes, 99.9% of Ce 4+ rejected and concentrated during vacuum distillation ( Ren et al., 2018 ) Electrodialysis Sc 20 ppm, 40 ppm, 80 ppm Sc 3+ 0.1M sulfuric acid as catholyte and anolyte in rinse compartments Anion exchange membrane (PC SA [the anion-exchange membrane obtained from PCCell with strongly alkaline with polyester reinforcement]), cation exchange membrane (PC SK the cation-exchange membrane procured from PCCell with strongly acidic with sulfonic acid functional groups]), both from PCell 99.52% of Sc 3+ removed from 20 ppm solution at 3 V ( Li et al., 2021 ) Electrodialysis Nd, Dy, Tb Anthracite coal ash leached with nitric acid Nitric acid, 0.01 M NaNO 3 Cation exchange membrane (CR67, MKIII, blank, GE Water & Processing Technologies) Tb: 90% extracted, 55% recovered Nd: 80% extracted, 74% recovered Dy: 74% extracted, 62% recovered All at 50 mA ( Couto et al., 2020 ) …”

Membrane distillation hybrids for water production and energy efficiency enhancement: A critical review

“…New types of MD treatment systems combined with electrodialysis (ED-MD) [267] or electrocoagulation (EC-MD) [268] have recently emerged. In these systems, ED and EC modules were used for wastewater pretreatment before its desalination in the MD module.…”

Air-gap membrane distillation as a one-step process for textile wastewater treatment

“…This, coupled with the lower operating pressures than typical filtration processes, means MD can be more compact, can be constructed out of cheaper polymeric materials and have potentially lower capital costs than alternative technologies [21]. MD has so far largely been studied for the treatment of highly saline water streams (such as seawater or RO brines) but there is increasing research into its suitability for treating various kinds of wastewater, for such applications as the extraction of pharmaceutical products and rare-earth metals [22,23].…”