Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Fenton kinetics

Jacobs and Fenton (202) were the first to suggest the possible intermediacy of ion 242 in the hydrolysis of trisubstituted allenyl halides to give the corresponding propargyl alcohols as products. A detailed and elegant study of the solvolysis of a series of triarylchloroallenes, 243, has recently been carried out by Schiavelli and co-workers (203). Excellent first-order kinetics... [Pg.308]

The stoichiometry of the reduction by Fe(ll) of cumene hydroperoxide is 1 1 (in contrast to reduction of H2O2) but the ratio A[Fe(II)]/A[ROOH] increases greatly in the presence of oxygen. The Arrhenius parameters for reduction of this and related hydroperoxides are quite similar to those of the Fenton reaction (Table 21). The production of acetophenone and ethane in high yield and the simple, second-order kinetics are consistent with the scheme... [Pg.464]

August et al. (1998) conducted kinetic studies for the reaction of benzene (0.2 mM) and other monocyclic aromatics with Fenton s reagent (8 mM hydrogen peroxide [Fe ] = 0.1 mM) at 25 °C. They reported a reaction rate constant of 0.0530/min. [Pg.127]

In water, carbofuran reacted with OH radicals at a first-order rate constant of 2.2 x 10 /M-sec (Mabury and Crosby, 1996a). Benitez et al. (2002) reported an apparent pseudo-first-order rate constant ranging from 5.1 x 10to 19.5 x lO Vsec for the reaction of carbofuran with ozone in water. When ozone and UV radiation was used to study the degradation kinetics, the pseudo-first-order rate constant was 22.8 x 10 Vsec. Similarly, the oxidation of carbofuran by Fenton s reagent and UV radiation ranged from 17.2 x 10 to >200 x lO Vsec. [Pg.254]

Chemical/Physical. In an aqueous solution, nitrobenzene (100 pM) reacted with Fenton s reagent (35 pM). After 15 min, 2-, 3-, and 4-nitrophenol were identified as products. After 6 h, about 50% of the nitrobenzene was destroyed. The pH of the solution decreased due to the formation of nitric acid (Lipczynska-Kochany, 1991). August et al. (1998) conducted kinetic studies for the reaction of nitrobenzene (0.2 mM) and other monocyclic aromatics with Fenton s reagent (8 mM hydrogen peroxide [Fe ] = 0.1 mM) at 25 °C. They reported a reaction rate constant of 0.0260/min. [Pg.843]

August , R., Dias, A.O., Rocha, L.L., and Lago, R.M. Kinetics and mechanism of benzene derivative degradation with Fenton s reagent in aqueous medium studied by MIMS, / PA/s. Chem. A, 102(52) 10723-10727, 1998. [Pg.1628]

Kusic, H Koprivanac, N Loncaric Bozic, A Selanec, I. Photo-assisted Fenton type processes for the degradation of phenol a kinetic study. Journal of Hazardous Materials, 2006 in press. [Pg.71]

Kusic, H, Koprivanac, N Srsan, L. Azo dye degradation using Fenton type processes assisted by UV irradiation A kinetic study. Journal of Photochemistry and Photobiology A Chemistry, 2006 181 (2-3), 195-202. [Pg.72]

The kinetics of oxidation of aldehydes by the Fenton reagent [Fe(II)-H202-0H-] have been studied.89 It has been suggested that different reactivities of PhIO in iron(III)-porphyrin-catalysed alkene epoxidation may be due to the formation of a more reactive iron(IV)-0-IPh complex.90 The iron(m) complex of tetrakis(3,5-disulfonato-mesityl)porphyrin catalyses the oxidative degradation of 2,4,6-trichlorophenol to 2,6-dichloro-l,4-benzoquinone with KHSO5 as the oxygen atom donor a peroxidase-type oxidation is thought to be involved.91... [Pg.186]

Kang N, Lee DS, Yoon J (2002) Kinetic Modeling of Fenton Oxidation of Phenol and Monochlorophenols. Chemosphere 47 915... [Pg.492]

Duesterberg CK, Waite TD (2006) Process Optimization of Fenton Oxidation Using Kinetic Modeling. Environ Sci Technol 40 4189... [Pg.492]

Although Fenton (1894) studied the violet color in caustic alkali during oxidation of tartaric and racemic acids by ferrous salt and hydrogen peroxide, no reaction kinetic model was offered. Fenton reported that the color disappeared when acid was added. Also, it has been observed that fresh external air is more active than room air. Fenton performed different experiments using various amounts of ferrous and hydrogen peroxides and... [Pg.184]

Kinetic Rate Constants of Chlorinated Phenols by Fenton s Reagent... [Pg.192]

The effect of the ratio of H202 to Fe2+ on oxidation kinetics, the oxidation kinetics of THM mixtures, and the effect of the number of chlorine atoms in a THM on its oxidation were all investigated. Bromoform is the easiest to oxidize of the four THMs. Bromoform concentrations used in the study of Fenton s reagent ratio and oxidation kinetics were 49.2, 98.3, and 295 pg/L. As the ratio of H202 to Fe2+ increases, the removal efficiency increases with... [Pg.204]

The oxidation rates for bromoform were slower than the oxidation rates of unsaturated chlorinated aliphatic compounds, including the TCE. Because the hydroxylation rate constant of TCE is 109 Mr1 s 1 and the hydrogen abstraction of bromoform is 1.1 x 108 M 1 s aromatics and alkenes react more rapidly by hydroxyl addition to double bonds than does the more kinetically difficult hydrogen atom abstraction. No oxidative destruction of chloroform by Fenton s reagent was experimentally observed an explanation for this is that both H202 and Fe2+ have rate constants about one magnitude higher with respect to hydroxyl radicals than chloroform. [Pg.206]

Martin et al. (1989) studied the oxidation of HMSA by Fenton s reagent and investigated the decomposition of both hydrogen peroxide and HMSA. They determined an estimate of the absolute rate of reaction between HMSA and hydroxyl radicals. The decomposition of hydrogen peroxide follows the first-order kinetics and can be described as follows ... [Pg.207]

As discussed earlier, the effects of the meta, para, and ortho positions of chlorine on the dechlorination kinetics of monochlorophenols, dichlorophenols, and trichlorophenols during Fenton oxidation were evaluated by comparing the rate constants of the kinetic model (Tang and Huang, 1995). This study proposed a pseudo first-order steady state with respect to organic concentration. The proposed reaction pathways considered that the hydroxyl radicals would attack unoccupied sites of the aromatic ring. [Pg.212]

Tang, W.Z. and Huang, C.P., The effect of chlorine position of chlorinated phenols on their dechlorination kinetics by Fenton s reagent, Waste Manage., 15(8), 615-622, 1995. [Pg.245]


See other pages where Fenton kinetics is mentioned: [Pg.129]    [Pg.129]    [Pg.404]    [Pg.489]    [Pg.129]    [Pg.131]    [Pg.516]    [Pg.271]    [Pg.372]    [Pg.241]    [Pg.953]    [Pg.362]    [Pg.198]    [Pg.530]    [Pg.70]    [Pg.220]    [Pg.310]    [Pg.627]    [Pg.186]    [Pg.6]    [Pg.183]    [Pg.189]    [Pg.194]    [Pg.199]    [Pg.205]    [Pg.212]    [Pg.215]    [Pg.222]    [Pg.241]    [Pg.242]   
See also in sourсe #XX -- [ Pg.129 ]




SEARCH



Fenton

Kinetics Fenton chemistry

Kinetics, anodic Fenton treatment

© 2024 chempedia.info