Co-reporter:Jichen Sun;Xiyang Dong;Mingxiang Chen ;Jiti Zhou
Journal of Chemical Technology and Biotechnology 2015 Volume 90( Issue 9) pp:1692-1698
Publication Date(Web):
DOI:10.1002/jctb.4479
Abstract
BACKGROUND
Wet absorption via addition of Fe(II)EDTA combined with biological reduction for nitric oxide removal is a promising approach. Based on existing issues and related studies of NOx scrubber solution, a dual-chamber MFC system with a biocathode was utilized to perform simultaneous and continuous reduction of Fe(III)EDTA and Fe(II)EDTA-NO with energy recovery.
RESULTS
The experimental results showed that in this system almost all of the Fe(II)EDTA-NO was removed and the spent NOx scrubber liquor (consisting of Fe(II)EDTA-NO and Fe(III)EDTA) was regenerated 50%, combined with electricity generation of 15.3 Am-3 NCC at the same time. Microorganisms utilized Fe(II)EDTA and cathodic electrodes as electron donor for Fe(II)EDTA-NO reduction and, different from the complicated Fe(II)EDTA-NO reduction process, the electrode was the sole electron donor for Fe(III)EDTA reduction. Additionally, Fe(II)EDTA-NO and Fe(III)EDTA mutually inhibits each other, mostly due to the competition for electrons. The microbial community of the biocathode was dominated by members of the Betaproteobacteria class.
CONCLUSION
This study first proposed and confirmed that microbial fuel cells could be utilized for the regeneration of NOx removal liquor which provided a novel pathway for NO removal combined with energy recovery. © 2014 Society of Chemical Industry
Co-reporter:Mingxiang Chen;Jiti Zhou
World Journal of Microbiology and Biotechnology 2015 Volume 31( Issue 3) pp:527-534
Publication Date(Web):2015 March
DOI:10.1007/s11274-015-1813-6
A viable process concept, based on NO and SO2 absorption into an alkaline Fe(II)EDTA (EDTA: ethylenediaminetetraacetic acid) solution in a scrubber combined with biological reduction of the absorbed SO2 utilizing sulfate reducing bacteria (SRB) and regeneration of the scrubbing liquor in a single bioreactor, was developed. The SRB, Desulfovibrio sp. CMX, was used and its sulfate reduction performances in FeEDTA solutions and Fe(II)EDTA-NO had been investigated. In this study, the detailed regeneration process of Fe(II)EDTA solution, which contained Fe(III)EDTA and Fe(II)EDTA-NO reduction processes in presence of D. sp. CMX and sulfate, was evaluated. Fe(III)EDTA and Fe(II)EDTA-NO reduction processes were primarily biological, even if Fe(III)EDTA and Fe(II)EDTA-NO could also be chemically convert to Fe(II)EDTA by biogenic sulfide. Regardless presence or absence of sulfate, more than 87 % Fe(III)EDTA and 98 % Fe(II)EDTA-NO were reduced in 46 h, respectively. Sulfate and Fe(III)EDTA had no affection on Fe(II)EDTA-NO reduction. Sulfate enhanced final Fe(III)EDTA reduction. Effect of Fe(III)EDTA on Fe(II)EDTA-NO reduction rate was more obvious than effect of sulfate on Fe(II)EDTA-NO reduction rate before 8 h. To overcome toxicity of Fe(II)EDTA-NO on SRB, Fe(II)EDTA-NO was reduced first and the reduction of Fe(III)EDTA and sulfate occurred after 2 h. First-order Fe(II)EDTA-NO reduction rate and zero-order Fe(III)EDTA reduction rate were detected respectively before 8 h.
Co-reporter:Xiyang Dong;Jiti Zhou;Hongyang Li;Xiaojun Wang ;Mingxiang Chen
Journal of Chemical Technology and Biotechnology 2014 Volume 89( Issue 1) pp:111-116
Publication Date(Web):
DOI:10.1002/jctb.4112
Abstract
BACKGROUND
The integrated approach of using metal chelate (e.g. Fe(II)EDTA) absorption combined with microbial reduction for nitric oxide (NO) removal has been a frequent topic of much recent study. The present study was undertaken to evaluate simultaneous Fe(II)EDTA-NO and Fe(III)EDTA with Paracoccus denitrificans as a model microorganism.
RESULTS
The experimental results suggested that Fe(III)EDTA reduction was severely inhibited by Fe(II)EDTA-NO while the addition of Fe(III)EDTA could have a positive effect on the reduction of Fe(II)EDTA-NO. Riboflavin, AQDS and vitamin B12 at 0.1 mmol L−1 did not have significant effects on simultaneous reduction of Fe(II)EDTA-NO and Fe(III)EDTA. Addition of sulfide not only could directly react with Fe(II)EDTA-NO and Fe(III)EDTA but also might play multiple roles in biological Fe(II)EDTA-NO reduction and Fe(III)EDTA reduction. The respiratory inhibitor CuCl2 inhibited Fe(II)EDTA-NO reduction as well as Fe(III)EDTA reduction while NaN3 and rotenone showed no measurable effects.
CONCLUSIONS
The present study showed that Fe(II)EDTA-NO reduction and Fe(III)EDTA reduction reacted upon each other. The roles of sulfide were divided in terms of biological and chemical interactions during the simultaneous reduction. CuCl2 could inhibit the simultaneous reduction rates. © 2013 Society of Chemical Industry
Co-reporter:Ning Li;Yanmei Li;Mingxiang Chen;Xiyang Dong ;Jiti Zhou
Journal of Chemical Technology and Biotechnology 2013 Volume 88( Issue 2) pp:311-316
Publication Date(Web):
DOI:10.1002/jctb.3833
Abstract
BACKGROUND: In the BioDeNOX technology for NOX removal from flue gas, bioreduction of Fe(II)EDTA-NO and Fe(III)EDTA are core processes. In this study, a newly isolated strain, Paracoccus denitrificans, was used to reduce Fe(II)EDTA-NO with glucose and Fe(II)EDTA as donor electrons. To better understand the change law of Fe(II)EDTA, the process of Fe(II)EDTA-NO reduction by P. denitrificans with glucose and Fe(II)EDTA as electron donors was investigated, and the factors that might affect Fe(II)EDTA concentration were studied.
RESULTS: For the bioreduction process of Fe(II)EDTA-NO, P. denitrificans could use glucose and Fe(II)EDTA as electron donors. At different stages, primary electron donors were different, thereby affecting the concentration of Fe(II)EDTA in the system. It was also proved that this strain not only reduced Fe(III)EDTA with glucose as the electron donor but also secreted several substances that reacted with Fe(III)EDTA, resulting in increased Fe(II)EDTA concentration in the solution.
CONCLUSIONS: This work has shown that P. denitrificans can reduce Fe(II)EDTA-NO and Fe(III)EDTA simultaneously to regenerate NOX absorption solution. © 2012 Society of Chemical Industry
Co-reporter:Xiaojun Wang, Yu Zhang, Xiyang Dong, Mingxiang Chen, Zhuang Shi, and Jiti Zhou
Energy & Fuels 2013 Volume 27(Issue 10) pp:6024-6030
Publication Date(Web):September 26, 2013
DOI:10.1021/ef401095f
In the BioDeNOx process for the nitrogen oxides (NOx) removal, sulfide is supposed to exist in the bioreactor mainly because of the bioreduction of sulfite and sulfate. Thus, the potential roles of sulfide should be taken into account in the BioDeNOx process. The objective of this work was to investigate abiotic Fe(II)EDTA–NO reduction by sulfide with respect to stoichiometry and kinetics. Batch experiments showed that elemental sulfur and ammonium were the two major products. However, the molar ratio of reduced Fe(II)EDTA–NO to the oxidized sulfide was 1:3.4–1:3.6, a bit higher than the expected value, suggesting the formation of the polysulfide based on the comprehensive analysis. Results also showed that Fe(II)EDTA–NO reduction by sulfide was a first-order reaction with respect to Fe(II)EDTA–NO. The reduction rates of Fe(II)EDTA–NO by sulfide went up along with the decrease of the pH values and rise of the reaction temperature. Besides, the energy of activation (Ea) and the entropy of activation (ΔS⧧) were 31.125 kJ mol–1 and −67.6144 J K–1 mol–1, respectively. Apart from the investigation into the abiotic role of sulfide on the BioDeNOx process, this paper also provided a hint on an integrated chemical and biological process for simultaneous desulfurization and denitrification.
Co-reporter:Yu Zhang, Jiti Zhou, Chengyu Li, Shiyuan Guo, and Guodong Wang
Industrial & Engineering Chemistry Research 2012 Volume 51(Issue 3) pp:1158-1165
Publication Date(Web):December 14, 2011
DOI:10.1021/ie2014372
The reaction kinetics of the Fe(II)-induced catalytic oxidation of S(IV) in a concentration range of 10–6 M ≤ [Fe(II)] ≤ 1 M was studied. The S(IV) catalytic oxidation reaction order for O2 and HSO3– was found to be 0 and 1 in this iron concentration range. The reaction order toward Fe(II) was 1 for 10–6 M ≤ [Fe(II)] ≤ 10–4 M, 0 for 10–4 M < [Fe(II)] ≤ 10–2 M, and −0.2 for 10–2 M ≤ [Fe(II)] ≤ 1 M. At 30–50 °C the activation energy values were low but increased after an increase in the ionic strength. The ionic strength had a negative influence on the reaction rate constant in the iron concentration range. By analyzing the radical mechanisms and reaction kinetic results, a simplified model for the Fe(II)-induced catalytic oxidation of S(IV), which enables a better analysis and elucidation of the experimental results, is proposed.
![Ferrate(2-),[[N,N'-1,2-ethanediylbis[N-[(carboxy-kO)methyl]glycinato-kN,kO]](4-)]-, hydrogen (1:2), (OC-6-21)-](http://img.cochemist.com/ccimg/21400/21393-59-9.png)
![Ferrate(2-),[[N,N'-1,2-ethanediylbis[N-[(carboxy-kO)methyl]glycinato-kN,kO]](4-)]-, hydrogen (1:2), (OC-6-21)-](http://img.cochemist.com/ccimg/21400/21393-59-9_b.png)
![Ferrate(2-),[[N,N'-1,2-ethanediylbis[N-[(carboxy-kO)methyl]glycinato-kN,kO]](4-)]-, (OC-6-21)-](http://img.cochemist.com/ccimg/15700/15651-72-6.png)
![Ferrate(2-),[[N,N'-1,2-ethanediylbis[N-[(carboxy-kO)methyl]glycinato-kN,kO]](4-)]-, (OC-6-21)-](http://img.cochemist.com/ccimg/15700/15651-72-6_b.png)
![5a,6-Dihydro-5a,6,6-trimethyl-2,8-dinitro-12H-indolo[2,1-b][1,3]benzoxazine](http://img.cochemist.com/ccimg/1023700/1023640-20-1.png)
![5a,6-Dihydro-5a,6,6-trimethyl-2,8-dinitro-12H-indolo[2,1-b][1,3]benzoxazine](http://img.cochemist.com/ccimg/1023700/1023640-20-1_b.png)
![Benzenamine, N,N-diphenyl-4-[2-(trimethylsilyl)ethynyl]-](/data/chemimg/133600/205877-25-4.png)
![Benzenamine, N,N-diphenyl-4-[2-(trimethylsilyl)ethynyl]-](/data/chemimg/133600/205877-25-4_b.png)
![Ferrate(1-),[[N,N'-1,2-ethanediylbis[N-[(carboxy-kO)methyl]glycinato-kN,kO]](4-)]-, (OC-6-21)-](http://img.cochemist.com/ccimg/15300/15275-07-7.png)
![Ferrate(1-),[[N,N'-1,2-ethanediylbis[N-[(carboxy-kO)methyl]glycinato-kN,kO]](4-)]-, (OC-6-21)-](http://img.cochemist.com/ccimg/15300/15275-07-7_b.png)