Abstract
A Chemical absorption-bioelectrochemical reduction (CABER) system is based on Chemical absorption-biological reduction (CABR) system, which aims at NO removal and has been studied in many of our previous works. In this paper, we applied polypyrrole (PPy) on the electrode of bioelectrochemical reactor (BER) of CABER system, which induced a much higher current density in the cyclic voltammetry (CV) curve for the electrode itself and better NO removal rate in the system. In addition, a Microbial Electrolysis Cell (MEC) is constructed to study its strengthening mechanism. Results shows that PPy-MEC has a greater Faraday efficiency and higher reduction rate of Fe(III)EDTA and Fe(II)EDTA-NO in the solution when compared to original Carbon MEC, which confirms the advantage of PPy-modified electrode(s) in the CABER system. The results of this study are reported for illustration of potential of CABER technology and design of low-cost high-efficiency NOx control equipment in the future.
Highlights
Emission limitation of NOx, which are major precursors of PM2.51, is an urgent task for thermal power plants in the field of air pollution control
Part of the Fe(II)ethylenediaminetetraacetic acid (EDTA) is oxidized to Fe(III)EDTA by oxygen; Fe(II)EDTA-NO is reduced to Fe(II)EDTA and N2 in the biological electric reactor (BER) with electron donors such as glucose, electron from external voltage/current or even Fe(II)EDTA itself 5,6,13: 2Fe(II)EDTA − NO2− + 4 e− + 4H+ mic roor gan is→m 2Fe(II)EDTA2− + N2 + 2H2O
There are debate on the primary electron donor, previous researches have reveal that the biofilm electrode reactor (BER), is the core part of the Chemical absorption-bioelectrochemical reduction (CABER) technology; as the speed-limiting process, biological reduction of Fe(III)EDTA is the key that restrict the efficiency of the system[14,15], and the electron pathway of Fe(III)EDTA bioreduction is a direct electron transfer process[16]
Summary
Emission limitation of NOx, which are major precursors of PM2.51, is an urgent task for thermal power plants in the field of air pollution control. A chemical absorption-bioelectrochemical reduction (CABER) integrated system, is based on the previous chemical absoprtion-biological reduction (CABR) system which is developed for highly efficient NOx removal in the flue gas[2,3,4,5,6], and uses biofilm electrode to enhance the system operation through strengthening the reduction process. According to the properties of polymers, electronic donors or acceptors are doped, and electrons are injected or removed into the molecular chains of conductive polymers, so as to optimize the electronic conductivity of conductive polymers They have been successfully used in fields of battery cathodes[20], microelectronics[21], nonlinear optics[22], and sensors[23], etc. It is hoped that this work can provide more evidence of potential of the CABER technology and insights in design of new low-cost air pollution control equipment which is still a vacancy in the practical application of high-efficient NO removal
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
