Name: Electrochemically and Bioelectrochemically Induced Ammonium Recovery (Video) | JoVE Journal
Uploaded: 2015-01-22T15:00:00.000+00:00
Duration: 9 min 50 s
Description: Learn electrochemical and bioelectrochemical methods for ammonium recovery from nitrogen-rich waste streams using ion exchange membranes. This technique enables sustainable nutrient extraction for environmental engineering applications.

ai_agent_IP

ai_agent

maintenance

instantTrialDurationMinutes

isBiopharma

enableNewMyJoveSectionDesign

educationFeatures

seoMetaApi

ai_copilot_institution_blacklist

ai_chat_institution_blacklist

freeAccessWindow

ssoRoleCapture

scheduledMaintenanceBanner

joveLabsFeatures

disable_autoplay_for_bots

extended_trial_duration

5 minutes

This work was supported by the BOF grant for SG from Ghent University. AL is supported by the Rutgers University NSF Fuels-IGERT. SA is supported by the European Union Framework Programme 7 project &#8220;ProEthanol 2G.&#8221; SA and KR are supported by Ghent University Multidisciplinary Research Partnership (MRP)&#8212;Biotechnology for a sustainable economy (01 MRA 510W). JD is supported by an IOF Advanced grant (F2012/IOF-Advanced/094). KR is supported by by the ERC Starter Grant &#8220;Electrotalk&#8221;. The authors thank Tim Lacoere for designing the TOC art figure, Robin Declerck for building the strip and absorption columns and Kun Guo for providing the inoculum source.

<ol><li>Verstraete, W., Van de Caveye, P., Diamantis, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Maximum+use+of+resources+present+in+domestic+%22used+water%22%5BTitle%5D)+AND+%22Bioresource+Technology%22%5BJournal%5D)">Maximum use of resources present in domestic "used water".</a> Bioresource Technology. 100 (23), 5537-5545 (2009).</li>
<li>Lei, X., Sugiura, N., Feng, C., Maekawa, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Pretreatment+of+anaerobic+digestion+effluent+with+ammonia+stripping+and+biogas+purification%5BTitle%5D)+AND+%22Journal+of+Hazardous+Materials%22%5BJournal%5D)">Pretreatment of anaerobic digestion effluent with ammonia stripping and biogas purification.</a> Journal of Hazardous Materials. 145 (3), 391-397 (2007).</li>
<li>Siegrist, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Nitrogen+removal+from+digester+supernatant-comparison+of+chemical+and+biological+methods%5BTitle%5D)+AND+%22Water+Science+and+Technology%22%5BJournal%5D)">Nitrogen removal from digester supernatant-comparison of chemical and biological methods.</a> Water Science and Technology. 34 (1), 399-406 (1996).</li>
<li>Desloover, J., Abate Woldeyohannis, A., Verstraete, W., Boon, N., Rabaey, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Electrochemical+Resource+Recovery+from+Digestate+to+Prevent+Ammonia+Toxicity+during+Anaerobic+Digestion%5BTitle%5D)+AND+%22Environmental+Science+%26+Technology%22%5BJournal%5D)">Electrochemical Resource Recovery from Digestate to Prevent Ammonia Toxicity during Anaerobic Digestion.</a> Environmental Science & Technology. 46 (21), 12209-12216 (2012).</li>
<li>Kim, J. R., Zuo, Y., Regan, J. M., Logan, B. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Analysis+of+ammonia+loss+mechanisms+in+microbial+fuel+cells+treating+animal+wastewater%5BTitle%5D)+AND+%22Biotechnology+and+Bioengineering%22%5BJournal%5D)">Analysis of ammonia loss mechanisms in microbial fuel cells treating animal wastewater.</a> Biotechnology and Bioengineering. 99 (5), 1120-1127 (2008).</li>
<li>Emerson, K., Russo, R. C., Lund, R. E., Thurston, R. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Aqueous+ammonia+equilibrium+calculations%3A+effect+of+pH+and+temperature%5BTitle%5D)+AND+%22Journal+of+the+Fisheries+Board+of+Canada%22%5BJournal%5D)">Aqueous ammonia equilibrium calculations: effect of pH and temperature.</a> Journal of the Fisheries Board of Canada. 32 (12), 2379-2383 (1975).</li>
<li>Kuntke, P., Sleutels, T. H. J. A., Saakes, M., Buisman, C. J. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Hydrogen+production+and+ammonium+recovery+from+urine+by+a+Microbial+Electrolysis+Cell%5BTitle%5D)+AND+%22International+Journal+of+Hydrogen+Energy%22%5BJournal%5D)">Hydrogen production and ammonium recovery from urine by a Microbial Electrolysis Cell.</a> International Journal of Hydrogen Energy. 39 (10), 4771-4778 (2014).</li>
<li>Guo, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Surfactant+treatment+of+carbon+felt+enhances+anodic+microbial+electrocatalysis+in+bioelectrochemical+systems%5BTitle%5D)+AND+%22Electrochemistry+Communications%22%5BJournal%5D)">Surfactant treatment of carbon felt enhances anodic microbial electrocatalysis in bioelectrochemical systems.</a> Electrochemistry Communications. 39, 1-4 (2014).</li>
<li>Guo, K., Chen, X., Freguia, S., Donose, B. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Spontaneous+modification+of+carbon+surface+with+neutral+red+from+its+diazonium+salts+for+bioelectrochemical+systems%5BTitle%5D)+AND+%22Biosensors+and+Bioelectronics%22%5BJournal%5D)">Spontaneous modification of carbon surface with neutral red from its diazonium salts for bioelectrochemical systems.</a> Biosensors and Bioelectronics. 47, 184-189 (2013).</li>
<li><a target="_blank" href="http://scholar.google.com/scholar?hl=en&safe=off&q=%22Standard+Methods+For+The+Examination+Of+Water+And+Wastewater%22">Standard Methods For The Examination Of Water And Wastewater</a>. Rice, E. W., Greenberg, A. E., Clesceri, L. S., Eaton, A. D. , American Public Health Association. (1992).</li>
<li>Andersen, S. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Electrolytic+Membrane+Extraction+Enables+Production+of+Fine+Chemicals+from+Biorefinery+Sidestreams%5BTitle%5D)+AND+%22Environmental+Science+%26+Technology%22%5BJournal%5D)">Electrolytic Membrane Extraction Enables Production of Fine Chemicals from Biorefinery Sidestreams.</a> Environmental Science & Technology. 48 (12), 7135-7142 (2014).</li>
<li>Harnisch, F., Rabaey, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((The+Diversity+of+Techniques+to+Study+Electrochemically+Active+Biofilms+Highlights+the+Need+for+Standardization%5BTitle%5D)+AND+%22Chemsuschem%22%5BJournal%5D)">The Diversity of Techniques to Study Electrochemically Active Biofilms Highlights the Need for Standardization.</a> Chemsuschem. 5 (6), 1027-1038 (2012).</li>
<li>Clauwaert, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Minimizing+losses+in+bio-electrochemical+systems%3A+the+road+to+applications%5BTitle%5D)+AND+%22Applied+Microbiology+and+Biotechnology%22%5BJournal%5D)">Minimizing losses in bio-electrochemical systems: the road to applications.</a> Applied Microbiology and Biotechnology. 79 (6), 901-913 (2008).</li>
<li>Atkins, P., De Paula, J. <a target="_blank" href="http://scholar.google.com/scholar?hl=en&safe=off&q=author%3aAtkins%2C+P+%22Elements+of+Physical+Chemistry%22">Elements of Physical Chemistry</a>. , Oxford University Press. Oxford, UK. (2012).</li>
<li>Aelterman, P., Freguia, S., Keller, J., Verstraete, W., Rabaey, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((The+anode+potential+regulates+bacterial+activity+in+microbial+fuel+cells%5BTitle%5D)+AND+%22Applied+Microbiology+and+Biotechnology%22%5BJournal%5D)">The anode potential regulates bacterial activity in microbial fuel cells.</a> Applied Microbiology and Biotechnology. 78 (3), 409-418 (2008).</li>
<li>Kuntke, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Ammonium+recovery+and+energy+production+from+urine+by+a+microbial+fuel+cell%5BTitle%5D)+AND+%22Water+Research%22%5BJournal%5D)">Ammonium recovery and energy production from urine by a microbial fuel cell.</a> Water Research. 46 (8), 2627-2636 (2012).</li>
<li>Liu, H., Cheng, S., Logan, B. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Power+Generation+in+Fed-Batch+Microbial+Fuel+Cells+as+a+Function+of+Ionic+Strength%5BTitle%5D)+AND+%22Temperature%2C+and+Reactor+Configuration.+Environmental+Science+%26+Technology%22%5BJournal%5D)">Power Generation in Fed-Batch Microbial Fuel Cells as a Function of Ionic Strength.</a> Temperature, and Reactor Configuration. Environmental Science & Technology. 39 (14), 5488-5493 (2005).</li>
<li>Gimkiewicz, C., Harnisch, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Waste+Water+Derived+Electroactive+Microbial+Biofilms%3A+Growth%2C+Maintenance%2C+and+Basic+Characterization%5BTitle%5D)+AND+%22JoVE%22%5BJournal%5D)">Waste Water Derived Electroactive Microbial Biofilms: Growth, Maintenance, and Basic Characterization.</a> JoVE. (82), e50800(2013).</li>
<li>Ping, Q., Cohen, B., Dosoretz, C., He, Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Long-term+investigation+of+fouling+of+cation+and+anion+exchange+membranes+in+microbial+desalination+cells%5BTitle%5D)+AND+%22Desalination%22%5BJournal%5D)">Long-term investigation of fouling of cation and anion exchange membranes in microbial desalination cells.</a> Desalination. 325, 48-55 (2013).</li>
<li>Guerin, T., Mondido, M., McClenn, B., Peasley, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Application+of+resazurin+for+estimating+abundance+of+contaminant-degrading+micro-organisms%5BTitle%5D)+AND+%22Letters+in+Applied+Microbiology%22%5BJournal%5D)">Application of resazurin for estimating abundance of contaminant-degrading micro-organisms.</a> Letters in Applied Microbiology. 32 (5), 340-345 (2001).</li>
</ol>

The authors have nothing to disclose.

This manuscript provides the necessary tools to set up a bioelectrochemical and an electrochemical cell for ammonium recovery. The calculations presented in the results section provide the parameters for evaluation of the system performance. The biological and electrochemical systems are similar in setup and function. The main difference between the two systems is the choice of a fixed current for the electrochemical cell versus a fixed anode potential for the bioelectrochemical setup. The fixed current for the abiotic s...

Recovery of valuable products from wastewater gains importance as valuable resources become scarce and treatment without recovery represents only a cost. Wastewater contains both energy and nutrients that can be recovered, and nutrient recovery can help to close the production loop1. Recovery of energy through anaerobic digestion is a well-established process, while recovery of nutrients is less common. Recovery of nutrients from liquid waste streams such as urine and manure has been widely investigated, e.g., through the production of struvite and direct stripping of ammonia2,3. However, the need for chemical addition is a downside of these processes4. Here we present a technique for the recovery of cationic nutrients from waste streams, including both potassium and ammonium. The cationic form of these nutrients allows recovery using an ion selective membrane in an electrochemical system. In this case, the electrochemical system consists of an anode chamber (where oxidation takes place), a cathode chamber (where reduction takes place) and an ion selective membrane to separate the compartments. A voltage is applied across the cell to produce a current flow from anode to cathode. This voltage can be generated by an external power source to drive water oxidation and reduction reactions. Alternatively the anodic oxidation, e.g., of organics, can be catalyzed by electroactive bacteria, requiring less power. To close the circuit and maintain the charge balance, a charged species must migrate between the electrodes for each electron generated. Ammonium transport from the anode chamber to the cathode chamber across a cation exchange membrane (CEM) can thus compensate the flux of electrons 4,5.
The technique presented here not only removes ammonium from waste streams, but also enables its recovery. Total ammonia nitrogen (TAN) exists in equilibrium of both ammonium (NH4+) and ammonia (NH3), and is dependent on pH and temperature6. NH4+ is abundantly available due to high TAN concentration and near neutral pH in the anode chamber and this positively charged species can therefore be driven by the current across the CEM into the cathode chamber. The current drives the reduction of water at the cathode, leading to the production of hydroxide ions and hydrogen gas. The TAN equilibrium shifts to nearly 100% NH3 due to the high pH in the cathode chamber (&#62; 10.0). NH3 is a gas that can be easily transferred via air circulation from the stripping unit to the absorption column where it is trapped and concentrated in an acid solution.
This technology has the potential to decrease ammonium toxicity during anaerobic digestion of N-rich streams like manure, thus increasing the energy recovery from these waste streams, while simultaneously recovering nutrients4. Electrochemical and bioelectrochemical extraction of ammonium can also be applied as nutrient recovery technique on waste streams with a high TAN content such as urine thereby avoiding costs for nutrient removal at a WWTP7.
The protocol presented here can serve as a basis for many different electrochemical and bioelectrochemical experiments, as we use a modular reactor. Different electrode types, membranes and frame thicknesses can be combined as explained in the protocol below. The main aim of the protocol is to provide a means for the comparison of electrochemical ammonium recovery and bio-electrochemical ammonium recovery using an electrolysis cell. The systems are evaluated in terms of extraction efficiency, power input and reproducibility.

<table><tbody><tr><td>Carbon Felt 3.18 mm Thick</td><td>Alfa Aesar</td><td>ALFA43199</td><td>Used as bioanode, 110&amp;nbsp;mm x 110&amp;nbsp;mm</td></tr><tr><td>Ti electrode coated with Ir MMO&amp;nbsp;</td><td>Magneto Special Anodes (The Netherlands)</td><td></td><td>Used as stable anode for electrochemical tests</td></tr><tr><td>Stainless steel mesh</td><td>Solana (Belgium)</td><td>RVS 554/64: material AISI 316L, mesh width: 564 micron, wire thickness: 140 micron, mesh number: 36,6</td><td>Used as cathode, 110&amp;nbsp;mm x 110&amp;nbsp;mm</td></tr><tr><td>Stainless steel plate</td><td>Solana (Belgium)</td><td>inox 304 sheet, thickness: 0.5 mm</td><td>Used as current collector for the bioanode</td></tr><tr><td>Ag/AgCl Reference Electrode</td><td>Bio-Logic (France)</td><td>A-012167 RE-1B</td><td></td></tr><tr><td>Potentiostat (VSP Multipotentiostat)&amp;nbsp;</td><td>Bio-Logic (France)</td><td></td><td></td></tr><tr><td>EC Lab</td><td>Bio-Logic (France)</td><td></td><td>software for performing electrochemistry measurements</td></tr><tr><td>Cation Exchange Membrane</td><td>Membranes International (USA)</td><td>Ultrex CMI-7000</td><td>Pretreated according to the manufacturers&#039; instructions</td></tr><tr><td>Turbulence Promotor mesh</td><td>ElectroCell Europe A/S (Tarm, Denmark)</td><td>EPC20432-PP-2</td><td>spacer material, 110 mm x 110 mm</td></tr><tr><td>Connectors</td><td>Serto</td><td>1,281,161,120</td><td>Other sizes possible, dependant on tubing type and size of holes in frames</td></tr><tr><td>Strip and absorption column</td><td></td><td></td><td>In house design</td></tr><tr><td>Tubing</td><td>Masterflex</td><td>HV-06404-16</td><td></td></tr><tr><td>Gas bag</td><td>Keika Ventures</td><td></td><td>Kynar gas bag with Roberts valve</td></tr><tr><td>Rashig Rings</td><td>Glasatelier Saillart (Belgium)</td><td>Raschig rings 4 x 4 mm</td><td>Put inside the strip and absorption column to improve the air/liquid contact. Available with many suppliers</td></tr><tr><td>Rubber sheet</td><td></td><td></td><td>Cut to fit on the perspex frames</td></tr><tr><td>Perspex reactor frames</td><td>Vlaeminck, Beernem</td><td></td><td>In-house design, see tab &quot;reactor frames&quot; in this file</td></tr></tbody></table>

electrochemically and bioelectrochemically induced ammonium recovery

Electrochemically and Bioelectrochemically Induced Ammonium Recovery

Streams such as urine and manure can contain high levels of ammonium, which could be recovered for reuse in agriculture or chemistry. The extraction of ammonium from an ammonium-rich stream is demonstrated using an electrochemical and a bioelectrochemical system. Both systems are controlled by a potentiostat to either fix the current (for the electrochemical cell) or fix the potential of the working electrode (for the bioelectrochemical cell). In the bioelectrochemical cell, electroactive bacteria catalyze the anodic reaction, whereas in the electrochemical cell the potentiostat applies a higher voltage to produce a current. The current and consequent restoration of the charge balance across the cell allow the transport of cations, such as ammonium, across a cation exchange membrane from the anolyte to the catholyte. The high pH of the catholyte leads to formation of ammonia, which can be stripped from the medium and captured in an acid solution, thus enabling the recovery of a valuable nutrient. The flux of ammonium across the membrane is characterized at different anolyte ammonium concentrations and currents for both the abiotic and biotic reactor systems. Both systems are compared based on current and removal efficiencies for ammonium, as well as the energy input required to drive ammonium transfer across the cation exchange membrane. Finally, a comparative analysis considering key aspects such as reliability, electrode cost, and rate is made.
This video article and protocol provide the necessary information to conduct electrochemical and bioelectrochemical ammonia recovery experiments. The reactor setup for the two cases is explained, as well as the reactor operation. We elaborate on data analysis for both reactor types and on the advantages and disadvantages of bioelectrochemical and electrochemical systems.

Chronoamperometry results from the bioreactor
The chronoamperometry results, calculated according to Equation 1, show a typical graph for a continuous reactor (Figure 4). At the start of the experiment, the anode and cathode were operated in recirculation mode. This allows a biofilm to develop and the onset of the current production. After 5 days of operation, the current density reached a maximum, followed by a decrease in current production. This is an indic...

We demonstrate the extraction of ammonium from an ammonium-rich stream using an electrochemical and a bioelectrochemical system. The reactor setup, operation and data analysis are discussed.

Streams such as urine and manure can contain high levels of ammonium, which could be recovered for reuse in agriculture or chemistry. The extraction of ...

The overall goal of the following experiment is to investigate the recovery of nutrients from nitrogen rich streams using either an electrochemical or bio electrochemical approach. The former approach is achieved by passing the stream through an electrochemical system, which after oxidation of water creates a driving force that can be used to flux charge ammonium from the anode side across an ion exchange membrane to the cathode side. As a second step, the high pH at the cathode side results in the conversion of ammonium to volatile ammonia.The high level of selectivity of the ion exchange membrane enables the creation of a pure ammonia hydrogen stream. Next, the catho is circulated through a stripping and absorption column in order to trap the ammonia in an acidic medium. The electrochemical extraction can also be driven by bio electrochemical processes, where the development of a biofilm on the anode allows the conversion of organics present in the waste stream into carbon dioxide, protons, and electrons.This will, again, drive a flux of ammonium from the anode to the cathode. The results show that both approaches can recover nutrients from nitrogen rich streams such as urine. The conventional nitrification denitrification approach on wastewater treatment takes the ammonia from the wastewater and turns it into nitrogen gas, which goes back in the atmosphere, so we lose the nitrogen.The advantage of our approach is that we take the ammonia and we recover it in a clean form so we can do something with it. We can reuse it or convert it to another product. A second advantage of our approach is that we use electricity as a driver.It's essentially a clean and cheap source of energy, and it avoids the use of chemicals. Demonstrating the procedure will be Sylvia Hilde Bain and Steven Anderson. Both PhD students from my lab Prior to starting this procedure collect all necessary material to build the reactor, including the electrodes, frames, and rubbers.After ensuring that the membrane is pretreated according to the manufacturer's instructions, pretreat the carbon felt electrode by soaking it in two millimolar acetyl trimethyl ammonium bromide, or A-C-T-A-B for three minutes. Then rinse the carbon felt electrode with demineralized water. Following this, stack the different reactor parts in order according to the reactor type.Then stack the reactor parts for the electrochemical cell. Use nuts and bolts to close the reactor and hand tighten the bolts on opposite sides to equalize the pressure. Seal the connection ports of the reactor using Teflon.Make sure the port is properly tightened. Place the reference electrode in the same compartment as the working electrode. Next, fill the reactor with water to test if it is leak free.If leaks are observed, check if the bolts are tightened enough or if one of the reactor parts moved while assembling the reactor. If no leaks are detected, empty the water from the reactor. Connect the feed and recirculation pumps to the reactor and the air pump to the stripping and absorption units.Fill the absorption column with 250 milliliters of one molar sulfuric acid to cover the che rings. Ensure that the Airstream mixes the acid well when the pump is switched on. After preparing analyte and catalyte solutions, flush the analyte by purging with nitrogen gas for at least 30 minutes to remove oxygen.For the inoculum, prepare a 30 milliliter mixture of effluence from active anaerobic bioreactors, including a bio anode. Collect the mixture in a syringe. Next, connect a gas bag filled with nitrogen to the analyte bottle.In order to keep the pressure stable while not allowing oxygen to enter. Mix the inoculum source with the volume of analyte by emptying the syringe with inoculum into the medium bottle using a syringe filled the anode and cathode compartments simultaneously with their respective solutions. When both reactor compartments are filled, turn on the recirculation pump at a recirculation rate of approximately six liters per hour.Following this, connect the potential stat cable with three electrodes using the anode as the working electrode. Switch on the potential stat in chrono aberrometry mode. Using the potentials stat software, select a fixed anode potential of negative 200 millivolts versus the silver, silver chloride reference electrode to change to continuous feeding.Switch on the feed pump for the anode and cathode at a hydraulic residence. Time of six hours switch on the air pump of the strip and absorption unit. Then recirculate the air in a closed loop.Refresh the medium three times per week with fresh analyte and catalyte as described in the text. Attach a gas bag filled with nitrogen to the closed feed bottle. Stop the feed pump and put a clamp on the effluent line.Then switch the old and new bottles. Remove the clamps and restart the pump each time the feed is refreshed. Remove five milliliter liquid samples of the effluent and effluent of the analyte and catalyte for measurement of conductivity, pH acetate content and ammonium concentration.In addition, remove a three milliliter sample of the absorption column to monitor the pH and for total ammonium nitrogen or tan analysis. When the pH approaches four, replace the AB absorbent with fresh one molar sulfuric acid solution to ensure high absorption efficiency. If the current stabilization is not caused by acetate limitations, increase the ammonium concentration in the feed and wait for stabilization of the current.In order to assess extraction efficiencies for electrochemical extraction, prepare a synthetic wastewater stream as analyte according to the following table. Add ammonium sulfate to reach a final concentration of five grams of nitrogen per liter. Following this switch on the feed pump to fill the reactor compartments, reduce the pump speed to obtain a hydraulic residence time of six hours.Once the reactor is filled, as before, switch on the recirculation pump at a rate of six liters per hour. Then remove a five milliliter sample of the in fluent after starting the strip and absorption unit. Switch on the potential stat in chronometry mode using the potential stat software.First, apply a low current density of about 0.5 NPIs per meter squared for 24 hours to polarize the membrane and to determine nitrogen flux due to diffusion alone. When the system has been polarized for 24 hours, apply the current density necessary for the experiment, usually ranging from 10 amp piers per meter squared to 50 amp piers per meter squared. Once the reactor has reached steady state, take at least three five milliliter samples over a time course from the anode and cathode effluence as well as the absorption column.The chrono porometer results show a typical graph for a continuous reactor. The change to continuous operation on day six resulted in a continuous increase in current production until a plateau was reached at 3.5 ampers per meter squared between day 12 and 16. The influence of day and night temperature on the current production is clearly visible.For example, from day 42 to 46, the ammonium concentration in the feed was increased in several steps. The current increase was linked to an increased conductivity of the anode feed in which the addition of ammonium bicarbonate increased the ion concentration and thus the conductivity. The cell voltage for the electrochemical system is higher than for the bioreactor.This is mainly due to the higher anode potential required for electrochemical oxidation of water to oxygen. The nitrogen flux for the bioreactor is higher than the electrochemical system. This can be explained by the lower alkalinity of the feed of the electrochemical system, resulting in a lower analy pH h.This resulted in a higher competition between ammonium and protons to restore the charge balance over the membrane. This technique now paves the way for environmental engineers to explore biological and non-biological electrochemical recovery of charged species from waste streams such as anaerobic digest state. More specifically here, we've shown that a biological approach comes at a lower energy input, but may suffer from somewhat lower robustness and a longer startup time.The purely electrochemical approach may just deliver that robustness, but it will come at a somewhat higher cost. After watching this video, you should have a good understanding of how to set up a biochemical system for the recovery of ammonium from wastewater. You should be able to construct a robust and leak-free biochemical cell, and they strip an absorption unit to recover the ammonia.

electrochemically-and-bioelectrochemically-induced-ammonium-recovery

Research

JoVE Journal

Chemistry

Source: Okamoto, A., et al. Self-standing Electrochemical Set-up to Enrich Anode-respiring Bacteria On-site. J. Vis. Exp. (2018)This video demonstrates the use of an on-site electrochemical system to enrich anode-respiring bacteria (ARB) from natural reservoirs. A redox gradient is established by placing the anode in oxygen-free deep water and the cathode in oxygen-rich surface water. ARB form biofilms and transfer electrons to the anode, which flows to the cathode, where oxygen is reduced,...

Enrichment of Anode-Respiring Bacteria Using an On-Site Electrochemical System

Chronoamperometric growth of anodic electroactive microbial biofilms in a fed-batch reactor using a three-electrode setup, controlled by a potentiostat, is demonstrated. The extracellular electron transfer is characterized using cyclic voltammetry in the presence of the electron donor and in the absence of the electron donor. Fundamental data analysis is demonstrated.

Waste Water Derived Electroactive Microbial Biofilms: Growth, Maintenance, and Basic Characterization

Herein the procedures for plasma enhanced chemical vapor deposition of perfluoroalkanes on microporous materials such as metal-organic frameworks to enhance their stability and hydrophobicity are described. Furthermore, breakthrough testing of milligram quantities of samples is described in detail.

Preparation of Hydrophobic Metal-Organic Frameworks via Plasma Enhanced Chemical Vapor Deposition of Perfluoroalkanes for the Removal of Ammonia

A protocol for measuring electrical conductivity of living microbial biofilms under physiologically relevant conditions is presented.

Characterizing Electron Transport through Living Biofilms

Ammonia can be synthesized at low pressure by using a conventional catalyst and an ammonia selective absorbent.

Ammonia Synthesis at Low Pressure

Here we present a protocol of whole-cell electrochemical experiments to study the contribution of proton transport to the rate of extracellular electron transport via the outer-membrane cytochromes complex in Shewanella oneidensis MR-1.

Electrochemical Detection of Deuterium Kinetic Isotope Effect on Extracellular Electron Transport in Shewanella oneidensis MR-1

On-site microbial enrichment or in situ cultivation techniques can facilitate the isolation of difficult-to-culture microbial taxa, especially from low-biomass or geochemically extreme environments. Here, we describe an electrochemical set-up without using an external power source to enrich microbial strains that are capable of extracellular electron transport (EET).

Self-standing Electrochemical Set-up to Enrich Anode-respiring Bacteria On-site

A series of methods to determine the potential DNRA rate based on 14NH4+/15NH4+ analyses is provided in detail. NH4+ is converted into N2O via several steps and analyzed using quadrupole gas chromatography–mass spectrometry.

Measurement of the Potential Rates of Dissimilatory Nitrate Reduction to Ammonium Based on 14NH4+/15NH4+ Analyses via Sequential Conversion to N2O

We demonstrate the fabrication of a reverse electrodialysis device using a cation-exchange membrane (CEM) and anion-exchange membrane (AEM) for power generation.

Ion-Exchange Membranes for the Fabrication of Reverse Electrodialysis Device

The NMR-solution structure of a metallochaperone model peptide with Cu (I) was determined, and a detailed protocol from sample preparation and 1D and 2D data collection to a three-dimensional structure is described.

Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR

Learn electrochemical and bioelectrochemical methods for ammonium recovery from nitrogen-rich waste streams using ion exchange membranes. This technique enables sustainable nutrient extraction for environmental engineering applications.

Electrochemically and Bioelectrochemically Induced Ammonium Recovery

Explore More Videos