Iron phosphomolybdate complexes in electrocatalytic reduction of aqueous disinfection byproducts


Bromberg L., Özbek N., Tan K., Su X., Padhye L. P. , Hatton T. A.

CHEMICAL ENGINEERING JOURNAL, vol.408, 2021 (Peer-Reviewed Journal) identifier identifier

  • Publication Type: Article / Article
  • Volume: 408
  • Publication Date: 2021
  • Doi Number: 10.1016/j.cej.2020.127354
  • Journal Name: CHEMICAL ENGINEERING JOURNAL
  • Journal Indexes: Science Citation Index Expanded, Scopus, Academic Search Premier, PASCAL, Aerospace Database, Aqualine, BIOSIS, Biotechnology Research Abstracts, CAB Abstracts, Chemical Abstracts Core, Chimica, Compendex, Food Science & Technology Abstracts, INSPEC, Pollution Abstracts, Veterinary Science Database, Civil Engineering Abstracts
  • Keywords: Electrocatalyst, Crystalline iron phosphomolybdate-bipyridylpropane complex, Electroreduction, Aqueous disinfection byproducts, ELECTROCHEMICAL REDUCTION, CHLORINATED HYDROCARBONS, COMPOSITE-MATERIALS, CYCLIC VOLTAMMETRY, ASCORBIC-ACID, HYDROGEN, WATER, DECHLORINATION, EVOLUTION, CATALYST

Abstract

The crystalline iron phosphomolybdate-bipyridylpropane complex (FePM-BPP) synthesized by hydrothermal method in water possesses two [(P4Mo6O31)-O-V](12-) subunits bridged by one Fe center. We discovered that the FePM-BPP complex is an electrocatalyst active at close-to-neutral pH in aqueous electrolytes, catalyzing reduction of a variety of carcinogenic disinfection byproducts (DBPs) such as chloroform, N-nitrosodimethylamine (NDMA), and bromate. Deposition of FePM-BPP onto the surface of carbon electrodes led to accelerated chloroform electroreduction at near-neutral pH, at potentials in the -0.52 to -0.27 V vs standard hydrogen electrode (SHE) range, with surface-normalized rate constant of chloroform reduction at ca. 140 L m(-2)h(-1), and over 40% of chloroform reduced at -0.27 V vs SHE after 1 h. The surface-normalized first-order rate constants of the NDMA and bromate electroreduction at - 0.77 V vs SHE and pH 5.5 or 6.4 were estimated to be 250 and 150 L m(-2)h(-1), respectively. The simple synthetic route with low-cost, earth-abundant components, and versatility indicate that FePM-BPP can be considered for incorporation into DBP reduction processes as a heterogeneous catalyst.