{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,11]],"date-time":"2025-11-11T12:11:47Z","timestamp":1762863107439,"version":"build-2065373602"},"reference-count":41,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2020,11,24]],"date-time":"2020-11-24T00:00:00Z","timestamp":1606176000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100008530","name":"European Regional Development Fund","doi-asserted-by":"publisher","award":["POCI-01-0247-FEDER-007678"],"award-info":[{"award-number":["POCI-01-0247-FEDER-007678"]}],"id":[{"id":"10.13039\/501100008530","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["UIDB\/50011\/2020 & UIDP\/50011\/202"],"award-info":[{"award-number":["UIDB\/50011\/2020 & UIDP\/50011\/202"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Catalysts"],"abstract":"<jats:p>In the present study, two photocatalytic graphene oxide (GO) and carbon nanotubes (CNT) modified TiO2 materials thermally treated at 300 \u00b0C (T300_GO and T300_CNT, respectively) were tested and revealed their conversion efficiency of nitrogen oxides (NOx) under simulated solar light, showing slightly better results when compared with the commercial Degussa P25 material at the initial concentration of NOx of 200 ppb. A chemical kinetic model based on the Langmuir\u2013Hinshelwood (L-H) mechanism was employed to simulate micropollutant abatement. Modeling of the fluid dynamics and photocatalytic oxidation (PCO) kinetics was accomplished with computational fluid dynamics (CFD) approach for modeling single-phase liquid fluid flow (air\/NOx mixture) with an isothermal heterogeneous surface reaction. A tuning methodology based on an extensive CFD simulation procedure was applied to adjust the kinetic model parameters toward a better correspondence between simulated and experimentally obtained data. The kinetic simulations of heterogeneous photo-oxidation of NOx carried out with the optimized parameters demonstrated a high degree of matching with the experimentally obtained NOx conversion. T300_CNT is the most active photolytic material with a degradation rate of 62.1%, followed by P25-61.4% and T300_GO-60.4%, when irradiated, for 30 min, with emission spectra similar to solar light.<\/jats:p>","DOI":"10.3390\/catal10121366","type":"journal-article","created":{"date-parts":[[2020,11,24]],"date-time":"2020-11-24T09:06:28Z","timestamp":1606208788000},"page":"1366","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Experimental and Computational Analysis of NOx Photocatalytic Abatement Using Carbon-Modified TiO2 Materials"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2150-6241","authenticated-orcid":false,"given":"Tatiana","family":"Zhiltsova.","sequence":"first","affiliation":[{"name":"TEMA\u2014Centre for Mechanical Engineering and Automation, Mechanical Engineering Department, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9985-2806","authenticated-orcid":false,"given":"Nelson","family":"Martins","sequence":"additional","affiliation":[{"name":"TEMA\u2014Centre for Mechanical Engineering and Automation, Mechanical Engineering Department, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4338-5399","authenticated-orcid":false,"given":"Mariana R. F.","family":"Silva","sequence":"additional","affiliation":[{"name":"CICECO\u2014Aveiro Institute of Material, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Carla F. Da","family":"Silva","sequence":"additional","affiliation":[{"name":"CICECO\u2014Aveiro Institute of Material, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Mirtha A. O.","family":"Louren\u00e7o","sequence":"additional","affiliation":[{"name":"CICECO\u2014Aveiro Institute of Material, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0112-8570","authenticated-orcid":false,"given":"David M.","family":"Tobaldi","sequence":"additional","affiliation":[{"name":"CICECO\u2014Aveiro Institute of Material, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Daniel","family":"Covita","sequence":"additional","affiliation":[{"name":"Bosch Termotecnologia, S.A., Estrada Nacional 16, 3800-533 Cacia, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5174-7433","authenticated-orcid":false,"given":"Maria Paula","family":"Seabra","sequence":"additional","affiliation":[{"name":"CICECO\u2014Aveiro Institute of Material, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6578-8164","authenticated-orcid":false,"given":"Paula","family":"Ferreira","sequence":"additional","affiliation":[{"name":"CICECO\u2014Aveiro Institute of Material, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2020,11,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2200","DOI":"10.1021\/es000879i","article-title":"Effects of Surface Type and Relative Humidity on the Production and Concentration of Nitrous Acid in a Model Indoor Environment","volume":"35","author":"Wainman","year":"2001","journal-title":"Environ. Sci. Technol."},{"key":"ref_2","unstructured":"European Environment Agency (2019). Air Quality in Europe\u20142019 Report."},{"key":"ref_3","unstructured":"WHO (2010). WHO Guidelines for Indoor Air Quality: Selected Pollutants, WHO."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"104887","DOI":"10.1016\/j.envint.2019.05.081","article-title":"Human exposure to NO2 in school and office indoor environments","volume":"130","author":"Salonen","year":"2019","journal-title":"Environ. Int."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"250","DOI":"10.1080\/00022470.1982.10465397","article-title":"Indoor Byproduct Levels of Tobacco Smoke: A Critical Review of the Literature","volume":"32","author":"Sterling","year":"1982","journal-title":"J. Air Pollut. Control Assoc."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"522","DOI":"10.1016\/j.jenvman.2013.08.006","article-title":"An overview of photocatalysis phenomena applied to NOx abatement","volume":"129","author":"Andrade","year":"2013","journal-title":"J. Environ. Manag."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"29","DOI":"10.1016\/j.jphotochemrev.2012.08.002","article-title":"Removal of NOx by photocatalytic processes","volume":"14","author":"Lasek","year":"2013","journal-title":"J. Photochem. Photobiol. C Photochem. Rev."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"76","DOI":"10.1016\/j.cej.2014.03.078","article-title":"Pigmentary TiO2: A challenge for its use as photocatalyst in NOx air purification","volume":"261","author":"Bianchi","year":"2015","journal-title":"Chem. Eng. J."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"2261","DOI":"10.1039\/C5CY01627D","article-title":"NOx degradation in a continuous large-scale reactor using full-size industrial photocatalytic tiles","volume":"6","author":"Bianchi","year":"2016","journal-title":"Catal. Sci. Technol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"161","DOI":"10.1016\/S1010-6030(03)00005-4","article-title":"TiO2 photocatalytic oxidation of nitric oxide: Transient behavior and reaction kinetics","volume":"156","author":"Devahasdin","year":"2003","journal-title":"J. Photochem. Photobiol. A Chem."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"2481","DOI":"10.1016\/j.jeurceramsoc.2010.05.014","article-title":"Effects of SiO2 addition on TiO2 crystal structure and photocatalytic activity","volume":"30","author":"Tobaldi","year":"2010","journal-title":"J. Eur. Ceram. Soc."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"183","DOI":"10.1016\/j.apcatb.2018.10.032","article-title":"Sol gel graphene\/TiO2 nanoparticles for the photocatalytic-assisted sensing and abatement of NO2","volume":"243","author":"Giampiccolo","year":"2019","journal-title":"Appl. Catal. B Environ."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Rozman, N., Tobaldi, D.M., Cvelbar, U., Puliyalil, H., Labrincha, J.A., Legat, A., and \u0160kapin, A.S. (2019). Hydrothermal synthesis of rare-earth modified titania: Influence on phase composition, optical properties, and photocatalytic activity. Materials, 12.","DOI":"10.3390\/ma12050713"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"124099","DOI":"10.1016\/j.cej.2020.124099","article-title":"Carbon-modified titanium oxide materials for photocatalytic water and air decontamination","volume":"387","author":"Silva","year":"2020","journal-title":"Chem. Eng. J."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1616","DOI":"10.1021\/es051007p","article-title":"Photocatalytic Activity for Degradation of Nitrogen Oxides over Visible Light Responsive Titania-Based Photocatalysts","volume":"40","author":"Lin","year":"2006","journal-title":"Environ. Sci. Technol."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"206","DOI":"10.1016\/j.conbuildmat.2017.06.167","article-title":"Photocatalytic nano-composite architectural lime mortar for degradation of urban pollutants under solar and visible (interior) light","volume":"152","author":"Saeli","year":"2017","journal-title":"Constr. Build. Mater."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"5018","DOI":"10.1021\/ja711023z","article-title":"The Electronic Origin of the Visible-Light Absorption Properties of C-, N- and S-Doped TiO2 Nanomaterials","volume":"130","author":"Chen","year":"2008","journal-title":"J. Am. Chem. Soc."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"429","DOI":"10.1016\/S0926-3373(00)00258-7","article-title":"Photocatalytic oxidation of nitrogen oxide over titania\u2013zeolite composite catalyst to remove nitrogen oxides in the atmosphere","volume":"30","author":"Hashimoto","year":"2001","journal-title":"Appl. Catal. B Environ."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"245","DOI":"10.1016\/j.apcatb.2010.01.002","article-title":"NOx photocatalytic degradation employing concrete pavement containing titanium dioxide","volume":"95","author":"Ballari","year":"2010","journal-title":"Appl. Catal. B Environ."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"313","DOI":"10.1016\/j.cemconres.2009.09.013","article-title":"Photocatalytic degradation of air pollutants\u2014From modeling to large scale application","volume":"40","author":"Hunger","year":"2010","journal-title":"Cem. Concr. Res."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"58","DOI":"10.1016\/j.apcatb.2010.05.032","article-title":"Indoor air purification using heterogeneous photocatalytic oxidation. Part II: Kinetic study","volume":"99","author":"Yu","year":"2010","journal-title":"Appl. Catal. B Environ."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"82","DOI":"10.1016\/j.cattod.2018.09.001","article-title":"Photocatalytic NOx removal: Rigorous kinetic modelling and ISO standard reactor simulation","volume":"326","author":"Casado","year":"2019","journal-title":"Catal. Today"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"537","DOI":"10.1016\/j.cej.2016.06.090","article-title":"A review on photocatalysis for air treatment: From catalyst development to reactor design","volume":"310","author":"Boyjoo","year":"2017","journal-title":"Chem. Eng. J."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1601","DOI":"10.1016\/j.ces.2004.01.017","article-title":"Experimental and CFD analysis of photocatalytic gas phase vinyl chloride (VC) oxidation","volume":"59","author":"Mohseni","year":"2004","journal-title":"Chem. Eng. Sci."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1695","DOI":"10.1016\/j.ces.2008.12.021","article-title":"CFD modelling for a TiO2-coated glass-bead photoreactor irradiated by optical fibres: Photocatalytic degradation of oxalic acid","volume":"64","author":"Denny","year":"2009","journal-title":"Chem. Eng. Sci."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"5067","DOI":"10.1016\/j.ces.2010.05.024","article-title":"Prediction of photocatalytic air purifier apparatus performances with a CFD approach using experimentally determined kinetic parameters","volume":"65","author":"Queffeulou","year":"2010","journal-title":"Chem. Eng. Sci."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"724","DOI":"10.1002\/aic.12295","article-title":"Simulations of photodegradation of toluene and formaldehyde in a monolith reactor using computational fluid dynamics","volume":"57","author":"Chong","year":"2011","journal-title":"AIChE J."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"6916","DOI":"10.1021\/ie302838m","article-title":"Optimal Design of a Corrugated-Wall Photocatalytic Reactor Using Efficiencies in Series and Computational Fluid Dynamics (CFD) Modeling","volume":"52","author":"Alfano","year":"2013","journal-title":"Ind. Eng. Chem. Res."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1016\/j.jhazmat.2018.07.009","article-title":"Photocatalytic NOx abatement: Mathematical modeling, CFD validation and reactor analysis","volume":"372","author":"Padoin","year":"2019","journal-title":"J. Hazard. Mater."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.cej.2014.09.041","article-title":"Analytic versus CFD approach for kinetic modeling of gas phase photocatalysis","volume":"262","author":"Verbruggen","year":"2015","journal-title":"Chem. Eng. J."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"325","DOI":"10.1016\/j.cej.2014.11.017","article-title":"Kinetic analysis of TiO2-catalyzed heterogeneous photocatalytic oxidation of ethylene using computational fluid dynamics","volume":"263","author":"Einaga","year":"2015","journal-title":"Chem. Eng. J."},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Nakahara, K., Muttakin, M., Yamamoto, K., and Ito, K. (2019). Computational fluid dynamics modelling of the visible light photocatalytic oxidation process of toluene for indoor building materials with locally doped titanium dioxide. Indoor Built Environ., 1420326X19854499.","DOI":"10.1177\/1420326X19854499"},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Roegiers, J., van Walsem, J., and Denys, S. (2017). CFD- and radiation field modeling of a gas phase photocatalytic multi-tube reactor. Chem. Eng. J.","DOI":"10.1016\/j.cej.2018.01.047"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"298","DOI":"10.1016\/j.scs.2017.08.020","article-title":"Computational fluid dynamics modeling and parameterization of the visible light photocatalytic oxidation process of toluene for indoor building material","volume":"35","author":"Nakahara","year":"2017","journal-title":"Sustain. Cities Soc."},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Franses, E.I. (2014). Thermodynamics with Chemical Engineering Applications, Cambridge University Press.","DOI":"10.1017\/CBO9781107707009"},{"key":"ref_36","unstructured":"Ranade, V.V. (2002). Computational Flow Modeling for Chemical Reactor Engineering, Elsevier Science Publishing Co Inc."},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Ollis, D.F. (2018). Kinetics of Photocatalyzed Reactions: Five Lessons Learned. Front. Chem., 6.","DOI":"10.3389\/fchem.2018.00378"},{"key":"ref_38","unstructured":"Hussain, C.M. (2018). Chapter 4\u2014Mechanism of Adsorption on Nanomaterials. Nanomaterials in Chromatography, Elsevier."},{"key":"ref_39","unstructured":"ANSYS (2018). ANSYS Fluent Theory Guide 19.0, ANSYS, Inc."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"269","DOI":"10.1016\/0045-7825(74)90029-2","article-title":"The numerical computation of turbulent flows","volume":"3","author":"Launder","year":"1974","journal-title":"Comput. Methods Appl. Mech. Eng."},{"key":"ref_41","unstructured":"ANSYS (2018). ANSYS Fluent User\u2019s Guide 19.0, ANSYS, Inc."}],"container-title":["Catalysts"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-4344\/10\/12\/1366\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T10:36:29Z","timestamp":1760178989000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-4344\/10\/12\/1366"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,11,24]]},"references-count":41,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2020,12]]}},"alternative-id":["catal10121366"],"URL":"https:\/\/doi.org\/10.3390\/catal10121366","relation":{},"ISSN":["2073-4344"],"issn-type":[{"type":"electronic","value":"2073-4344"}],"subject":[],"published":{"date-parts":[[2020,11,24]]}}}