1
|
|
2
|
A Critical Review of Recent Progress and Perspective in Practical Denitration Application. Catalysts 2019. [DOI: 10.3390/catal9090771] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Nitrogen oxides (NOx) represent one of the main sources of haze and pollution of the atmosphere as well as the causes of photochemical smog and acid rain. Furthermore, it poses a serious threat to human health. With the increasing emission of NOx, it is urgent to control NOx. According to the different mechanisms of NOx removal methods, this paper elaborated on the adsorption method represented by activated carbon adsorption, analyzed the oxidation method represented by Fenton oxidation, discussed the reduction method represented by selective catalytic reduction, and summarized the plasma method represented by plasma-modified catalyst to remove NOx. At the same time, the current research status and existing problems of different NOx removal technologies were revealed and the future development prospects were forecasted.
Collapse
|
3
|
|
4
|
Removal dynamics of nitric oxide (NO) pollutant gas by pulse-discharged plasma technique. ScientificWorldJournal 2014; 2014:653576. [PMID: 24737985 PMCID: PMC3967449 DOI: 10.1155/2014/653576] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Accepted: 01/18/2014] [Indexed: 02/02/2023] Open
Abstract
Nonthermal plasma technique has drawn extensive attentions for removal of air pollutants such as NOx and SO2. The NO removal mechanism in pulse discharged plasma is discussed in this paper. Emission spectra diagnosis indicates that the higher the discharge voltage is, the more the NO are removed and transformed into O, N, N2, NO2, and so forth. Plasma electron temperature Te is ranged from 6400 K at 2.4 kV discharge voltage to 9500 K at 4.8 kV. After establishing a zero-dimensional chemical reaction kinetic model, the major reaction paths are clarified as the electron collision dissociation of NO into N and O during discharge and followed by single substitution of N on NO to form N2 during and after discharge, compared with the small fraction of NO2 formed by oxidizing NO. The reaction directions can be adjusted by N2 additive, and the optimal N2/NO mixing ratio is 2 : 1. Such a ratio not only compensates the disadvantage of electron competitive consumption by the mixed N2, but also heightens the total NO removal extent through accelerating the NO oxidization process.
Collapse
|
5
|
Yu Q, Wang H, Liu T, Xiao L, Jiang X, Zheng X. High-efficiency removal of NOx using a combined adsorption-discharge plasma catalytic process. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:2337-2344. [PMID: 22260249 DOI: 10.1021/es203405c] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A combined adsorption-discharge plasma catalytic process was used for the removal of NO(x) using zeolites as catalysts without external heating. It was found that the types of plasma carrier gases exert great effect on the conversion of adsorbed NO(x). The conversion of adsorbed NO(x) is much lower in N(2) plasma than in Ar plasma, which is attributed to the reverse reaction, NO(x) formation reaction. The momentary increase of oxygen species derived from the decomposition of adsorbed NO(x) is considered to be the main cause as their collisions with nitrogen species can generate NO(x) again. Thus, solid carbon was added to the catalyst to act as a scavenger for active oxygen species to improve the conversion of adsorbed NO(x) in N(2) plasma. A NO(x) removal rate of 97.8% was obtained on 8.5wt.% carbon mixed H-ZSM-5 at an energy efficiency of 0.758 mmol NO(x)/W·h.
Collapse
Affiliation(s)
- Qinqin Yu
- Key Lab of Applied Chemistry of Zhejiang Province, Department of Chemistry, Zhejiang University (XiXi Campus), Hangzhou 310028, China
| | | | | | | | | | | |
Collapse
|
6
|
Rico VJ, Hueso JL, Cotrino J, González-Elipe AR. Evaluation of different dielectric barrier discharge plasma configurations as an alternative technology for green C1 chemistry in the carbon dioxide reforming of methane and the direct decomposition of methanol. J Phys Chem A 2010; 114:4009-16. [PMID: 20184329 DOI: 10.1021/jp100346q] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Carbon dioxide reforming of methane and direct decomposition of methanol have been investigated using dielectric barrier discharges (DBD) at atmospheric pressure and reduced working temperatures. Two different plasma reactor configurations are compared and special attention is paid to the influence of the surface roughness of the electrodes on the conversion yields in the first plasma device. The influence of different filling gap dielectric materials (i.e., Al(2)O(3) or BaTiO(3)) in the second packed configuration has been also evaluated. Depending on the experimental conditions of applied voltage, residence time of reactants, feed ratios, or reactor configuration, different conversion yields are achieved ranging from 20 to 80% in the case of methane and 7-45% for the carbon dioxide. The direct decomposition of methanol reaches 60-100% under similar experimental conditions. Interestingly, the selectivity toward the production of hydrogen and carbon monoxide is kept almost constant under all the experimental conditions, and the formation of longer hydrocarbon chains or coke as a byproduct is not detected. The maximum efficiency yields are observed for the packed-bed reactor configuration containing alumina for both reaction processes (approximately 1 mol H(2) per kilowatt hour for dry reforming of methane and approximately 4.5 mol H(2) per kilowatt hour for direct decomposition of methanol).
Collapse
Affiliation(s)
- Víctor J Rico
- Instituto de Ciencia de Materiales de Sevilla (CSIC-Universidad de Sevilla), Spain
| | | | | | | |
Collapse
|
7
|
Morgan MM, Cuddy MF, Fisher ER. Gas-Phase Chemistry in Inductively Coupled Plasmas for NO Removal from Mixed Gas Systems. J Phys Chem A 2010; 114:1722-33. [DOI: 10.1021/jp908684c] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Michelle M. Morgan
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872
| | - Michael F. Cuddy
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872
| | - Ellen R. Fisher
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872
| |
Collapse
|
8
|
Abd El-sadek M, Ram Kumar J, Moorthy Babu S. The role of potassium tellurite as tellurium source in mercaptoacetic acid-capped CdTe nanoparticles. CURRENT APPLIED PHYSICS 2010; 10:317-322. [DOI: 10.1016/j.cap.2009.06.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
|
9
|
Hueso JL, Rico VJ, Cotrino J, Jiménez-Mateos JM, González-Elipe AR. Water plasmas for the revalorisation of heavy oils and cokes from petroleum refining. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2009; 43:2557-2562. [PMID: 19452916 DOI: 10.1021/es900236b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
This work investigates the possibility of using plasmas to treat high boiling point and viscous liquids (HBPVL) and cokes resulting as secondary streams from the refining of oil. For their revalorisation, the use of microwave (MW) induced plasmas of water is proposed, as an alternative to more conventional processes (i.e., catalysis, pyrolysis, combustion, etc.). As a main result, this type of energetic cold plasma facilitates the conversion at room temperature of the heavy aromatic oils and cokes into linear hydrocarbons and synthesis gas, commonly defined as syngas (CO + H2 gas mixture). The exposure of the coke to this plasma also facilitates the removal of the sulfur present in the samples and leads to the formation on their surface of a sort of carbon fibers and rods network and new porous structures. Besides, optical emission measurements have provided direct evidence of the intermediates resulting from the fragmentation of the heavy oils and cokes during their exposure to the water plasma. Furthermore, the analysis of the mass spectra patterns suggests a major easiness to break the aromatic bonds mainly contained in the heavy oils. Therefore, an innovative method for the conversion of low value residues from oil-refining processes is addressed.
Collapse
Affiliation(s)
- José L Hueso
- Instituto de Ciencia de Materiales de Sevilla (CSIC-Universidad de Sevilla), Avda. Américo Vespucio, 49, 41092, Sevilla, Spain.
| | | | | | | | | |
Collapse
|
10
|
Tsai CH, Kuo ZZ. Effects of additives on the selectivity of byproducts and dry removal of fluorine for abating tetrafluoromethane in a discharge reactor. JOURNAL OF HAZARDOUS MATERIALS 2009; 161:1478-1483. [PMID: 18550278 DOI: 10.1016/j.jhazmat.2008.04.118] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2008] [Revised: 04/26/2008] [Accepted: 04/28/2008] [Indexed: 05/26/2023]
Abstract
The removal efficiency of tetrafluoromethane (CF(4)) was significantly enhanced by adding additives (H(2), O(2), H(2)+O(2), H(2)O) in an atmospheric-pressure microwave plasma reactor. However, large amounts of fluorine (F(2)) were produced in this study. Moreover, the selectivity of F(2) was apparently greater than that of HF (in H(2)-based condition) or COF(2) (in O(2)-based abatement). Notably, in an O(2)-rich environment, more F(2) and a larger amount of CO(2) were produced. Subsequently, F(2) can be effectively removed by reacting with CaO to form CaF(2) at 200 degrees C via an in situ dry, chemical absorption process in the low-temperature afterglow discharge zone within the same plasma reactor.
Collapse
Affiliation(s)
- Cheng-Hsien Tsai
- Department of Chemical and Materials Engineering, National Kaohsiung University of Applied Sciences, 415 Chien-Kung Road, Kaohsiung 807, Taiwan.
| | | |
Collapse
|
11
|
Stillahn JM, Trevino KJ, Fisher ER. Plasma diagnostics for unraveling process chemistry. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2008; 1:261-291. [PMID: 20636081 DOI: 10.1146/annurev.anchem.1.031207.112953] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
This review focuses on the use of diagnostic tools to examine plasma processing chemistry, primarily plasma species energetics, dynamics, and molecule-surface reactions. We describe the use of optical diagnostic tools, mass spectrometry, and Langmuir probes in measuring species densities, rotational and kinetic energies, and plasma-surface reactions. Molecule-surface interactions for MX(n) species (M = C, Si, N; X = H, F, Cl) are presented and interpreted with respect to the molecule's electronic configuration and dipole moments.
Collapse
Affiliation(s)
- Joshua M Stillahn
- Department of Chemistry, Colorado State University, Fort Collins, 80523-1872, USA.
| | | | | |
Collapse
|
12
|
|
13
|
Barranco A, Aparicio F, Yanguas-Gil A, Groening P, Cotrino J, González-Elipe A. Optically Active Thin Films Deposited by Plasma Polymerization of Dye Molecules. ACTA ACUST UNITED AC 2007. [DOI: 10.1002/cvde.200606552] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
14
|
Tsai CH, Yang HH, Jou CJG, Lee HM. Reducing nitric oxide into nitrogen via a radio-frequency discharge. JOURNAL OF HAZARDOUS MATERIALS 2007; 143:409-14. [PMID: 17049159 DOI: 10.1016/j.jhazmat.2006.09.042] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2006] [Revised: 09/15/2006] [Accepted: 09/16/2006] [Indexed: 05/12/2023]
Abstract
NO/N(2)/O(2)/H(2)O mixtures are usually converted into HNO(3) and/or NO(2) using different discharge approaches. In this study, a radio-frequency discharge was successfully used to reduce NO mainly into N(2) at a low pressure (4kPa). The influences of experimental parameters, including carrier gas, inlet concentration of NO, O(2), steam, and applied power, are discussed. At least 95.7% of the total N atoms converted from NO into N(2). Other traces of byproducts were N(2)O and HNO(2), but neither HNO(3) nor NO(2) were detected. In addition, conversion of NO apparently increased with elevated applied power or decreased inlet concentration of O(2), reaching 92.8% and 74.2% for the NO/N(2)/O(2) (2%) and NO/N(2)/O(2) (6%)/H(2)O (10%) mixtures, respectively, at 120W. In addition, from the optical emission spectra, a large amount of N(2) (first positive band and second positive band) and NO (gamma system) were observed, and the important reactions for NO removal and N(2) formation are proposed.
Collapse
Affiliation(s)
- Cheng-Hsien Tsai
- Department of Chemical and Material Engineering, National Kaohsiung University of Applied Sciences, 415 Chien-Kung Road, Kaohsiung 807, Taiwan.
| | | | | | | |
Collapse
|
15
|
Hueso JL, Gonzalez-Elipe AR, Cotrino J, Caballero A. Removal of NO in NO/N2, NO/N2/O2, NO/CH4/N2, and NO/CH4/O2/N2 Systems by Flowing Microwave Discharges. J Phys Chem A 2007; 111:1057-65. [PMID: 17286359 DOI: 10.1021/jp063315v] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
In this paper, continuing previous work, we report on experiments carried out to investigate the removal of NO from simulated flue gas in nonthermal plasmas. The plasma-induced decomposition of small concentrations of NO in N2 used as the carrier gas and O2 and CH4 as minority components has been studied in a surface wave discharge induced with a surfatron launcher. The reaction products and efficiency have been monitored by mass spectrometry as a function of the composition of the mixture. NO is effectively decomposed into N2 and O2 even in the presence of O2, provided always that enough CH4 is also present in the mixture. Other majority products of the plasma reactions under these conditions are NH3, CO, and H2. In the absence of O2, decomposition of NO also occurs, although in that case HCN accompanies the other reaction products as a majority component. The plasma for the different reaction mixtures has been characterized by optical emission spectroscopy. Intermediate excited species of NO*, C*, CN*, NH*, and CH* have been monitored depending on the gas mixture. The type of species detected and their evolution with the gas composition are in agreement with the reaction products detected in each case. The observations by mass spectrometry and optical emission spectroscopy are in agreement with the kinetic reaction models available in literature for simple plasma reactions in simple reaction mixtures.
Collapse
Affiliation(s)
- José L Hueso
- Instituto de Ciencia de Materiales de Sevilla (CSIC-Universidad de Sevilla), Avda Américo Vespucio 49, 41092 Sevilla, Spain
| | | | | | | |
Collapse
|
16
|
Mello M, Potì B, Risi AD, Passaseo A, Lomascolo M, Vittorio MD. GaN optical system for CO and NO gas detection in the exhaust manifold of combustion engines. ACTA ACUST UNITED AC 2006. [DOI: 10.1088/1464-4258/8/7/s38] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|