Photocatalytic degradation of crystal violet by thiourea-doped TiO2 thin film fixed bed photoreactors under visible irradiation: Optimisation using central composite designs and kinetics studies by multivariate curve resolution
In this study, optimisation of the photocatalytic behaviour of crystal violet (CV) by thiourea (Tu)-codoped TiO2 thin film in fixed bed photoreactor was investigated by central composite designs (CCDs). The effective variables were pH, the concentration of CV dye, flow rate and reaction time. The re...
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| Format: | Article |
| Language: | English |
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Chemical Society of Ethiopia
2018-01-01
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| Series: | Bulletin of the Chemical Society of Ethiopia |
| Subjects: | |
| Online Access: | https://www.ajol.info/index.php/bcse/article/view/165341 |
| _version_ | 1811312407232905216 |
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| author | H. Khalilian A. Semnani M. Nekoeinia |
| author_facet | H. Khalilian A. Semnani M. Nekoeinia |
| author_sort | H. Khalilian |
| collection | DOAJ |
| description | In this study, optimisation of the photocatalytic behaviour of crystal violet (CV) by thiourea (Tu)-codoped TiO2 thin film in fixed bed photoreactor was investigated by central composite designs (CCDs). The effective variables were pH, the concentration of CV dye, flow rate and reaction time. The results of the CCD model showed a good agreement with experimental results, with R2 = 0.9680 (p < 0.0001) and maximum degradation efficiency was obtained at the optimum conditions: dye concentration 8.5 mg/L, pH 9, flow rate 6 mL/min and reaction time 80 min. Subsequently, three absorbing chemical compounds presented in the degradation reaction were obtained by using singular value decomposition (SVD) method and evolving factor analysis (EFA). Then a multivariate curve resolution with alternating least squares (MCR-ALS) was performed to achieve the concentration and spectral profiles for each component. Finally, a hard modelling method was applied to determine the kinetic constants of distinct reactions occurred in the photocatalytic degradation process. The reaction rate constants were calculated for the first and second steps as k1 = 0.08327 (SD = ±0.0015) /min and k2 = 0.045 (SD = ±0.0006)/min, respectively. |
| first_indexed | 2024-04-13T10:35:41Z |
| format | Article |
| id | doaj.art-292ba8d7f43f4537986cf58302081d40 |
| institution | Directory Open Access Journal |
| issn | 1011-3924 1726-801X |
| language | English |
| last_indexed | 2024-04-13T10:35:41Z |
| publishDate | 2018-01-01 |
| publisher | Chemical Society of Ethiopia |
| record_format | Article |
| series | Bulletin of the Chemical Society of Ethiopia |
| spelling | doaj.art-292ba8d7f43f4537986cf58302081d402022-12-22T02:50:03ZengChemical Society of EthiopiaBulletin of the Chemical Society of Ethiopia1011-39241726-801X2018-01-01313383396http://dx.doi.org/10.4314/bcse.v31i3.3Photocatalytic degradation of crystal violet by thiourea-doped TiO2 thin film fixed bed photoreactors under visible irradiation: Optimisation using central composite designs and kinetics studies by multivariate curve resolutionH. KhalilianA. SemnaniM. NekoeiniaIn this study, optimisation of the photocatalytic behaviour of crystal violet (CV) by thiourea (Tu)-codoped TiO2 thin film in fixed bed photoreactor was investigated by central composite designs (CCDs). The effective variables were pH, the concentration of CV dye, flow rate and reaction time. The results of the CCD model showed a good agreement with experimental results, with R2 = 0.9680 (p < 0.0001) and maximum degradation efficiency was obtained at the optimum conditions: dye concentration 8.5 mg/L, pH 9, flow rate 6 mL/min and reaction time 80 min. Subsequently, three absorbing chemical compounds presented in the degradation reaction were obtained by using singular value decomposition (SVD) method and evolving factor analysis (EFA). Then a multivariate curve resolution with alternating least squares (MCR-ALS) was performed to achieve the concentration and spectral profiles for each component. Finally, a hard modelling method was applied to determine the kinetic constants of distinct reactions occurred in the photocatalytic degradation process. The reaction rate constants were calculated for the first and second steps as k1 = 0.08327 (SD = ±0.0015) /min and k2 = 0.045 (SD = ±0.0006)/min, respectively.https://www.ajol.info/index.php/bcse/article/view/165341TiO2 thin filmPhotocatalytic degradationCentral composite designsMultivariate curve resolutionKinetic studying |
| spellingShingle | H. Khalilian A. Semnani M. Nekoeinia Photocatalytic degradation of crystal violet by thiourea-doped TiO2 thin film fixed bed photoreactors under visible irradiation: Optimisation using central composite designs and kinetics studies by multivariate curve resolution Bulletin of the Chemical Society of Ethiopia TiO2 thin film Photocatalytic degradation Central composite designs Multivariate curve resolution Kinetic studying |
| title | Photocatalytic degradation of crystal violet by thiourea-doped TiO2 thin film fixed bed photoreactors under visible irradiation: Optimisation using central composite designs and kinetics studies by multivariate curve resolution |
| title_full | Photocatalytic degradation of crystal violet by thiourea-doped TiO2 thin film fixed bed photoreactors under visible irradiation: Optimisation using central composite designs and kinetics studies by multivariate curve resolution |
| title_fullStr | Photocatalytic degradation of crystal violet by thiourea-doped TiO2 thin film fixed bed photoreactors under visible irradiation: Optimisation using central composite designs and kinetics studies by multivariate curve resolution |
| title_full_unstemmed | Photocatalytic degradation of crystal violet by thiourea-doped TiO2 thin film fixed bed photoreactors under visible irradiation: Optimisation using central composite designs and kinetics studies by multivariate curve resolution |
| title_short | Photocatalytic degradation of crystal violet by thiourea-doped TiO2 thin film fixed bed photoreactors under visible irradiation: Optimisation using central composite designs and kinetics studies by multivariate curve resolution |
| title_sort | photocatalytic degradation of crystal violet by thiourea doped tio2 thin film fixed bed photoreactors under visible irradiation optimisation using central composite designs and kinetics studies by multivariate curve resolution |
| topic | TiO2 thin film Photocatalytic degradation Central composite designs Multivariate curve resolution Kinetic studying |
| url | https://www.ajol.info/index.php/bcse/article/view/165341 |
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