Electrochemically-mediated selective capture of heavy metal chromium and arsenic oxyanions from water

The removal of highly toxic, ultra-dilute contaminants of concern has been a primary challenge for clean water technologies. Chromium and arsenic are among the most prevalent heavy metal pollutants in urban and agricultural waters, with current separation processes having severe limitations due to lack of molecular selectivity. Here, we report redox-active metallopolymer electrodes for the selective electrochemical removal of chromium and arsenic. An uptake greater than 100 mg Cr/g adsorbent can be achieved electrochemically, with a 99% reversible working capacity, with the bound chromium ions released in the less harmful trivalent form. Furthermore, we study the metallopolymer response during electrochemical modulation by in situ transmission electron microscopy. The underlying mechanisms for molecular selectivity are investigated through electronic structure calculations, indicating a strong charge transfer to the heavy metal oxyanions. Finally, chromium and arsenic are remediated efficiently at concentrations as low as 100 ppb, in the presence of over 200-fold excess competing salts.Chromium and arsenic are prevalent water pollutants, but their removal is currently limited by low selectivity. Here, the authors use redox-active metallopolymer electrodes based on poly(vinyl)ferrocene to selectively remove the two heavy metal oxyanions at concentrations as low as 100 ppb.

[1]  Volker Presser,et al.  Water desalination via capacitive deionization : What is it and what can we expect from it? , 2015 .

[2]  D. Stamatialis,et al.  Electrochemical reduction of dilute chromate solutions on carbon felt electrodes , 2006 .

[3]  S. Grimme,et al.  A consistent and accurate ab initio parametrization of density functional dispersion correction (DFT-D) for the 94 elements H-Pu. , 2010, The Journal of chemical physics.

[4]  N. Oyama,et al.  Investigation of ion and solvent transport accompanying redox reactions of polyvinylferrocene films using an in situ electrochemical quartz crystal microbalance technique , 1991 .

[5]  Yong Liu,et al.  Review on carbon-based composite materials for capacitive deionization , 2015 .

[6]  Xiaofeng Qian,et al.  In situ observation of random solid solution zone in LiFePO₄ electrode. , 2014, Nano letters.

[7]  Silvia Ahualli,et al.  Use of Soft Electrodes in Capacitive Deionization of Solutions. , 2017, Environmental science & technology.

[8]  J. Farmer,et al.  Electrosorption of Chromium Ions on Carbon Aerogel Electrodes as a Means of Remediating Ground Water , 1997 .

[9]  T. A. Hatton,et al.  Polyvinylferrocene for noncovalent dispersion and redox-controlled precipitation of carbon nanotubes in nonaqueous media. , 2013, Langmuir : the ACS journal of surfaces and colloids.

[10]  C. Rajagopal,et al.  Removal of Chromium from Aqueous Solutions by Treatment with Carbon Aerogel Electrodes Using Response Surface Methodology , 2005 .

[11]  Emma L. Smith,et al.  Use of neutron reflectivity to measure the dynamics of solvation and structural changes in polyvinylferrocene films during electrochemically controlled redox cycling. , 2009, Langmuir : the ACS journal of surfaces and colloids.

[12]  E. Yuliwati,et al.  A Review , 2019, Current Trends and Future Developments on (Bio-) Membranes.

[13]  S. Moon,et al.  Removal of chromium from water and wastewater by ion exchange resins. , 2001, Journal of hazardous materials.

[14]  S. Kanel,et al.  Spectroscopic investigation of Cr(III)- and Cr(VI)-treated nanoscale zerovalent iron. , 2007, Environmental science & technology.

[15]  Bruce E. Logan,et al.  Low Energy Desalination Using Battery Electrode Deionization , 2017 .

[16]  Richard G. Hennig,et al.  Accuracy of exchange-correlation functionals and effect of solvation on the surface energy of copper , 2013 .

[17]  Choonsoo Kim,et al.  Hybrid capacitive deionization to enhance the desalination performance of capacitive techniques , 2014 .

[18]  J. Sawai,et al.  Changes in aquatic toxicity of potassium dichromate as a function of water quality parameters. , 2017, Chemosphere.

[19]  T. A. Hatton,et al.  Electrosorption at functional interfaces: from molecular-level interactions to electrochemical cell design. , 2017, Physical chemistry chemical physics : PCCP.

[20]  G. Kresse,et al.  From ultrasoft pseudopotentials to the projector augmented-wave method , 1999 .

[21]  M. Elimelech,et al.  The Future of Seawater Desalination: Energy, Technology, and the Environment , 2011, Science.

[22]  A. Hillman,et al.  Time-resolved mono-anion, di-anion, and solvent transfers into a poly(vinylferrocene)-modified electrode , 1998 .

[23]  Kendra Letchworth-Weaver,et al.  Implicit solvation model for density-functional study of nanocrystal surfaces and reaction pathways. , 2013, The Journal of chemical physics.

[24]  A. Kushima,et al.  Charging/Discharging Nanomorphology Asymmetry and Rate-Dependent Capacity Degradation in Li-Oxygen Battery. , 2015, Nano letters.

[25]  T. A. Hatton,et al.  Redox-electrodes for selective electrochemical separations. , 2017, Advances in colloid and interface science.

[26]  X. Font,et al.  Chromium VI adsorption on cerium oxide nanoparticles and morphology changes during the process. , 2010, Journal of hazardous materials.

[27]  G. Henkelman,et al.  A grid-based Bader analysis algorithm without lattice bias , 2009, Journal of physics. Condensed matter : an Institute of Physics journal.

[28]  Janet G Hering,et al.  Comparison of arsenic(V) and arsenic(III) sorption onto iron oxide minerals: implications for arsenic mobility. , 2003, Environmental science & technology.

[29]  Lars Jarup,et al.  Hazards of heavy metal contamination. , 2003 .

[30]  C. Santhosh,et al.  Magnetic SiO[2]@CoFe[2]O[4] nanoparticles decorated on graphene oxide as efficient adsorbents for the removal of anionic pollutants from water , 2017 .

[31]  A. Hillman,et al.  Film mass and volume changes accompanying redox-driven solvent and salt transfer during redox switching of polyvinylferrocene films , 1998 .

[32]  Timothy F. Jamison,et al.  Anion‐Selective Redox Electrodes: Electrochemically Mediated Separation with Heterogeneous Organometallic Interfaces , 2016 .

[33]  T. Langrish,et al.  Adsorption of Chromium(VI) from Aqueous Solutions Using Cross-Linked Magnetic Chitosan Beads , 2009 .

[34]  A. Hillman,et al.  Counter-ion specific effects on charge and solvent trapping in poly(vinylferrocene) films , 2000 .

[35]  S. Fendorf,et al.  Reduction of Hexavalent Chromium by Amorphous Iron Sulfide , 1997 .

[36]  Kresse,et al.  Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. , 1996, Physical review. B, Condensed matter.

[37]  S. K. Agarwal,et al.  Groundwater Contaminated with Hexavalent Chromium [Cr (VI)]: A Health Survey and Clinical Examination of Community Inhabitants (Kanpur, India) , 2012, PloS one.

[38]  Kazuo T. Suzuki,et al.  Arsenic round the world: a review. , 2002, Talanta.

[39]  K. Takeshita,et al.  Adsorption mechanism of hexavalent chromium by redox within condensed-tannin gel. , 2001, Water research.

[40]  M. Bazant,et al.  Liquid cell transmission electron microscopy observation of lithium metal growth and dissolution: Root growth, dead lithium and lithium flotsams , 2017 .

[41]  Guohua Chen,et al.  Removal and recovery of Cr(VI) from wastewater by maghemite nanoparticles. , 2005, Water research.

[42]  William R. Dichtel,et al.  Rapid removal of organic micropollutants from water by a porous β-cyclodextrin polymer , 2015, Nature.

[43]  Allen J. Bard,et al.  Polymer Films on Electrodes XVI . In Situ Ellipsometric Measurements of Polybipyrazine, Polyaniline, and Polyvinylferrocene Films , 1985 .

[44]  Paul Ih-Fei Liu,et al.  Energy, Technology, And The Environment , 2004 .

[45]  Timothy F. Jamison,et al.  Asymmetric Faradaic systems for selective electrochemical separations , 2017 .

[46]  Guangchao Li,et al.  Kinetics of chromate reduction by ferrous iron , 1996 .

[47]  R. Murray,et al.  The effect of composition of a ferrocene-containing redox polymer on the electrochemistry of its thin film coatings on electrodes , 1983 .

[48]  P. M. Biesheuvel,et al.  Energy consumption and constant current operation in membrane capacitive deionization , 2012 .