Kinetic investigations of the oxidation of arylazonaphthol dyes in hypochlorite solutions as a function of pH

Oakes, John; Gratton, Peter

doi:10.1039/a805949g

Cited by 61 publications

(56 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The reactions R3 and R4 are the rate-controlling steps for dye oxidation. Literature data were used for R1 and R2 and for the reaction equilibrium between OCl -and HOCl 23,31 and the values used for R5 to R13 were estimated rate constants from the simulations. The estimated rate constants were optimized so that the simulated curves matched the experimental curves.…”

Section: Simulation Studiesmentioning

confidence: 99%

Kinetics and mechanism of the oxidation of Coomassie Brilliant Blue-R dye by hypochlorite and role of acid therein

Nadupalli¹,

Dasireddy²,

Koorbanally³

et al. 2015

S.Afr.j.chem

View full text Add to dashboard Cite

show abstract

Section: Simulation Studiesmentioning

confidence: 99%

Kinetics and mechanism of the oxidation of Coomassie Brilliant Blue-R dye by hypochlorite and role of acid therein

Nadupalli¹,

Dasireddy²,

Koorbanally³

et al. 2015

S.Afr.j.chem

View full text Add to dashboard Cite

show abstract

“…There are many processes available for removal of color from waste effluents, namely chemical oxidation (McClung and Lemley 1994), foam flotation (Lin and Lo 1996), electrolysis (Bousher et al 1997), biodegradation (Oakes and Gratton 1998), adsorption (Poulios and Aetopoulou 1999;Ncibi et al 2007), chemical coagulation (Papic et al 2000) and photocatalysis (Lopez-Grimau and Gutierrez 2006;Divya et al 2013). However, adsorption onto activated carbon seems to be one of the effective and reliable physicochemical treatment methods (Pala and Tokat 2002;Mall et al 2005) and due to economical and environmentally friendly reasons (Toor and Jin 2012).…”

Section: Introductionmentioning

confidence: 99%

Application of response surface methodology (RSM) for optimization of color removal from POME by granular activated carbon

Al-Khatib

Mamun

Akbar

2014

Int. J. Environ. Sci. Technol.

View full text Add to dashboard Cite

Color is one of the major remaining contaminants in the palm oil mill effluent (POME) following the conventional treatment of POME. The removal of color from POME using adsorption on activated carbon was investigated. The adsorption experimental design was performed using the standard response surface method (RSM) design that is central composite design to determine the optimum process variables for color removal by using the Design-Expert software (version 7.0. Stat-Ease, trial version). Besides obtaining optimum values, RSM also has the advantage of studying the interaction between various experimental parameters compared to one-factor-at-a-time. The equilibrium experimental data were analyzed by Langmuir and Freundlich isotherms. The statistical analysis showed that the quadratic model as well as the model terms was significant. The model had very low probability value (0.0003). The R 2 for the model was 0.9184 and the adjusted R 2 was 0.8380. The validation of the model showed experimental value and predicted value of 0.124 and 0.106, respectively. The optimum conditions suggested by the model for the process variable were 87.9 min, 4.05 and 7.86 g, for time, pH and granular activated carbon dose, respectively. The maximum removal obtained at these conditions was 89.95 %. The adsorption isotherm data were fitted well to the Langmuir isotherm compared to Freundlich isotherm with R 2 value of 0.850 for the former and 0.273 for the later.

show abstract

“…Azo dyes, such as Acid Orange 7, containing hydroxyl groups conjugated to azo group [31] exhibit azo-hydrazone tautomerism as shown below: …”

Section: Tautomerism Of Acid Orange 7 Dyementioning

confidence: 99%

RuCl3 Catalyzed and Uncatalyzed Oxidative Decolorization of Acid Orange 7 Dye with Chloramine-B in Acid Medium: Spectrophotometric, Kinetic and Mechanistic Study

Manjunatha

Puttaswamy

2015

Catal Lett

View full text Add to dashboard Cite

Acid orange 7, chemically known as sodium 4-[(2E)-2-(2-oxonaphthalen-1-ylidene)hydrazinyl]benzenesulfonate, is extensively used for dyeing textiles, paper and leather. The discharge of wastewater containing this dye, causes environmental and health related problems. Therefore, in the present research, we have developed optimum conditions for the facile oxidative decolorization of this dye with sodium N-chlorobenzenesulfonamide or chloramine-B (CAB). The kinetics and mechanism of oxidative decolorization of acid orange 7 dye with CAB in acidic medium have also been studied spectrophotometrically at 303 K in the presence and absence of RuCl 3 catalyst. Under similar experimental conditions, the reaction exhibits a first-order dependence of rate each on [CAB] o and [dye] o , and an inverse-fractional-order dependence on [H ? ] for both the RuCl 3 catalyzed and uncatalyzed reactions. The order with respect to RuCl 3 is fractional. Activation parameters have been computed. Dielectric effect is negative in both the cases. Oxidation products of the acid orange 7 dye are identified as 1,2-naphthoquinone and benzenesulfonic acid by GC-MS data. The RuCl 3 catalyzed reaction is about four fold faster than the uncatalyzed reaction. The chemical oxygen demand value of the dye was determined. The mechanistic pathways and kinetic modelings have been computed based on experimental results. The developed oxidative decolorization method is expected to be helpful to treat acid orange 7 dye present in wastewater after suitable modifications.Graphical Abstract The stoichiometry of the reaction is in the mole ratio of 1:1(AO7:CAB) in both the cases as shown given below

show abstract

Kinetic investigations of the oxidation of arylazonaphthol dyes in hypochlorite solutions as a function of pH

Cited by 61 publications

References 11 publications

Kinetics and mechanism of the oxidation of Coomassie Brilliant Blue-R dye by hypochlorite and role of acid therein

Kinetics and mechanism of the oxidation of Coomassie Brilliant Blue-R dye by hypochlorite and role of acid therein

Application of response surface methodology (RSM) for optimization of color removal from POME by granular activated carbon

RuCl3 Catalyzed and Uncatalyzed Oxidative Decolorization of Acid Orange 7 Dye with Chloramine-B in Acid Medium: Spectrophotometric, Kinetic and Mechanistic Study

Contact Info

Product

Resources

About