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Degradation and mineralization of phenol compounds with goethite catalyst and mineralization prediction using artificial intelligence.

Tisa F, Davoody M, Abdul Raman AA, Daud WM - PLoS ONE (2015)

Bottom Line: The efficiency of phenol degradation via Fenton reaction using mixture of heterogeneous goethite catalyst with homogeneous ferrous ion was analyzed as a function of three independent variables, initial concentration of phenol (60 to 100 mg /L), weight ratio of initial concentration of phenol to that of H2O2 (1: 6 to 1: 14) and, weight ratio of initial concentration of goethite catalyst to that of H2O2 (1: 0.3 to 1: 0.7).Two separate models were developed using artificial neural networks to predict degradation percentage by a combination of Fe3+ and Fe2+ catalyst.Satisfactory agreement was observed between testing data and the predicted values (R2Phenol = 0.9214 and R2TOC= 0.9082).

View Article: PubMed Central - PubMed

Affiliation: Department of Chemical Engineering, Faculty of Engineering, University of Malaya,50603 Kuala Lumpur, Malaysia.

ABSTRACT
The efficiency of phenol degradation via Fenton reaction using mixture of heterogeneous goethite catalyst with homogeneous ferrous ion was analyzed as a function of three independent variables, initial concentration of phenol (60 to 100 mg /L), weight ratio of initial concentration of phenol to that of H2O2 (1: 6 to 1: 14) and, weight ratio of initial concentration of goethite catalyst to that of H2O2 (1: 0.3 to 1: 0.7). More than 90 % of phenol removal and more than 40% of TOC removal were achieved within 60 minutes of reaction. Two separate models were developed using artificial neural networks to predict degradation percentage by a combination of Fe3+ and Fe2+ catalyst. Five operational parameters were employed as inputs while phenol degradation and TOC removal were considered as outputs of the developed models. Satisfactory agreement was observed between testing data and the predicted values (R2Phenol = 0.9214 and R2TOC= 0.9082).

No MeSH data available.


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pone.0119933.g001: Mechanism Description.

Mentions: It has been denoted that use of goethite catalyst can be effective in diminution of organic complexes [8,9,32]. Goethite and hydrogen peroxide can effectively oxidize organic compounds. Hence, batch experiments were performed in conical bottles with 100 mg/L phenol and 2 g/L goethite at initial pH 3 to examine the reductive oxidation effect of phenol by goethite. No degradation was observed within 60 min by using goethite alone; but highly efficient degradation was achieved with the use of ferrous sulphate. In a study of Ming-Chun Lu (1999), degradation of chlorophenol using only goethite catalyst was observed within 3 to 4 hours [8]. When goethite catalyst is used in Fenton oxidation, ferrous ions are produced from the reductive dissolution of goethite as shown below [8,33]α−FeOOH+3H++e−↔Fe2++3H2O(4)Electron is generated from hydrogen peroxide from the equation below,H2O2→2H++O2+2e−(5)Reaction 4 and 5 can be simplified to reaction 6,α−FeOOH+2H++12H2O2→Fe2++12O2+2H2O(6)The degradation would follow the classic steps corresponding to the Homogeneous Fenton reactions, among which are:Fe2++H2O2→Fe3++HO−+HOo(7)Fe3++H2O2→Fe2++H++HO2(8)The mechanism of phenol degradation can be explained by the above equations. Based on the literature, oxidation of phenol with H2O2 in presence of Fe2+ catalyst occurs when there is electrophilic attack by hydroxyl radical. A more complete mechanism can be found in work of authors [1,34]. A simplified mechanism is shown in Fig. 1.


Degradation and mineralization of phenol compounds with goethite catalyst and mineralization prediction using artificial intelligence.

Tisa F, Davoody M, Abdul Raman AA, Daud WM - PLoS ONE (2015)

Mechanism Description.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4388832&req=5

pone.0119933.g001: Mechanism Description.
Mentions: It has been denoted that use of goethite catalyst can be effective in diminution of organic complexes [8,9,32]. Goethite and hydrogen peroxide can effectively oxidize organic compounds. Hence, batch experiments were performed in conical bottles with 100 mg/L phenol and 2 g/L goethite at initial pH 3 to examine the reductive oxidation effect of phenol by goethite. No degradation was observed within 60 min by using goethite alone; but highly efficient degradation was achieved with the use of ferrous sulphate. In a study of Ming-Chun Lu (1999), degradation of chlorophenol using only goethite catalyst was observed within 3 to 4 hours [8]. When goethite catalyst is used in Fenton oxidation, ferrous ions are produced from the reductive dissolution of goethite as shown below [8,33]α−FeOOH+3H++e−↔Fe2++3H2O(4)Electron is generated from hydrogen peroxide from the equation below,H2O2→2H++O2+2e−(5)Reaction 4 and 5 can be simplified to reaction 6,α−FeOOH+2H++12H2O2→Fe2++12O2+2H2O(6)The degradation would follow the classic steps corresponding to the Homogeneous Fenton reactions, among which are:Fe2++H2O2→Fe3++HO−+HOo(7)Fe3++H2O2→Fe2++H++HO2(8)The mechanism of phenol degradation can be explained by the above equations. Based on the literature, oxidation of phenol with H2O2 in presence of Fe2+ catalyst occurs when there is electrophilic attack by hydroxyl radical. A more complete mechanism can be found in work of authors [1,34]. A simplified mechanism is shown in Fig. 1.

Bottom Line: The efficiency of phenol degradation via Fenton reaction using mixture of heterogeneous goethite catalyst with homogeneous ferrous ion was analyzed as a function of three independent variables, initial concentration of phenol (60 to 100 mg /L), weight ratio of initial concentration of phenol to that of H2O2 (1: 6 to 1: 14) and, weight ratio of initial concentration of goethite catalyst to that of H2O2 (1: 0.3 to 1: 0.7).Two separate models were developed using artificial neural networks to predict degradation percentage by a combination of Fe3+ and Fe2+ catalyst.Satisfactory agreement was observed between testing data and the predicted values (R2Phenol = 0.9214 and R2TOC= 0.9082).

View Article: PubMed Central - PubMed

Affiliation: Department of Chemical Engineering, Faculty of Engineering, University of Malaya,50603 Kuala Lumpur, Malaysia.

ABSTRACT
The efficiency of phenol degradation via Fenton reaction using mixture of heterogeneous goethite catalyst with homogeneous ferrous ion was analyzed as a function of three independent variables, initial concentration of phenol (60 to 100 mg /L), weight ratio of initial concentration of phenol to that of H2O2 (1: 6 to 1: 14) and, weight ratio of initial concentration of goethite catalyst to that of H2O2 (1: 0.3 to 1: 0.7). More than 90 % of phenol removal and more than 40% of TOC removal were achieved within 60 minutes of reaction. Two separate models were developed using artificial neural networks to predict degradation percentage by a combination of Fe3+ and Fe2+ catalyst. Five operational parameters were employed as inputs while phenol degradation and TOC removal were considered as outputs of the developed models. Satisfactory agreement was observed between testing data and the predicted values (R2Phenol = 0.9214 and R2TOC= 0.9082).

No MeSH data available.