ChemInform Abstract: THE M(C) ACTIVITY COEFFICIENT FUNCTION FOR ACID‐BASE EQUILIBRIA PART 1, NEW METHODS FOR ESTIMATING PK(A) VALUES FOR WEAK BASES

Marziano, Nunciata C.; Cimino, Giuseppe M.; Passerini, R.

doi:10.1002/chin.197407103

Cited by 4 publications

(6 citation statements)

References 1 publication

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“…Based on the rate expression given by Eq. 8, a rate equation has been proposed by Marziano and coauthors employing the M c function of sulfuric acid as follows6, 12, 13: where n is another thermodynamic parameter, which is unique for each aromatic compound. The M c function for sulfuric acid represents a general scale that depicts its acidity.…”

Section: Resultsmentioning

confidence: 99%

Nitration of nitrobenzene at high‐concentrations of sulfuric acid: Mass transfer and kinetic aspects

2009

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This article reports studies on mass transfer and kinetics of nitration of nitrobenzene at high concentrations of sulfuric acid in a batch reactor at different temperatures. The effects of concentration of sulfuric acid, speed of stirring, and temperature on mass transfer coefficient were investigated. The kinetics of nitration under homogenized conditions was studied at different sulfuric acid concentrations at these temperatures. The reaction rate constants were determined. The variation of rate constant with sulfuric acid concentration was explained by the M c function. The activation energies of the reactions were determined from the Arrhenius plots. The regimes of the reactions were determined using the values of the mass transfer coefficients and the reaction rate constants. A model was developed for simultaneous mass transfer and chemical reaction in the aqueous phase. The yields of the three isomers of dinitrobenzene were determined, and the variation of isomer distribution with sulfuric acid concentration and temperature was analyzed. This work demonstrates that more than 90% conversion of nitrobenzene is possible at high-sulfuric acid concentrations resulting in high yield of the product even at moderate temperatures and at low speeds of stirring.

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Section: Resultsmentioning

confidence: 99%

Nitration of nitrobenzene at high‐concentrations of sulfuric acid: Mass transfer and kinetic aspects

2009

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“…where k0 is the intrinsic reaction rate constant, which only depends on temperature. A (Marziano et al, 1983;Marziano et al, 1973;Marziano et al, 1981) was used in this work to describe the relationship between the activity and the sulfuric acid acidity. The rate equation is rewritten as Eq.…”

Section: Intrinsic Reaction Ratementioning

confidence: 99%

Continuous flow nitration of 3-[2-chloro-4-(trifluoromethyl) phenoxy] benzoic acid and its chemical kinetics within droplet-based microreactors

Zhang

et al. 2022

Chemical Engineering Science

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“…Based on the Brønsted‐Bjerrum rate law (transition‐state theory), 33,34 the nitration rate can be expressed as follows:

r goodbreak= k^{*} c_{CB} c_{{NO}_{2}^{+}} \frac{γ_{CB} γ_{{NO}_{2}^{+}}}{γ^{*}},

where k * is the rate constant based on NO 2 + and

γ_{CB}

γ_{{NO}_{2}^{+}}

, and

γ^{*}

are the activity coefficients for CB, NO 2 + , and the transition‐state intermediate, respectively.…”

Section: Resultsmentioning

confidence: 99%

“…The value of the activity coefficient is not easy to obtain. To calculate the p K a of weak bases in a study of acid–base equilibrium, Marziano et al 27,34 introduced the activity coefficient function M c to describe the change in the activity coefficient with acid strength:

r goodbreak= k^{*} c_{CB} c_{{NO}_{2}^{+}} 10^{{italicnM}_{c}},

where n is a thermodynamic parameter related to the type of aromatic compounds. The M c for sulfuric acid represents a general scale describing its acidity, and its value depends only on the concentration of sulfuric acid at a given temperature.…”

Section: Resultsmentioning

confidence: 99%

Determination of the kinetics of chlorobenzene nitration using a homogeneously continuous microflow

Cui

Song

et al. 2022

AIChE Journal

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The nitration of chlorobenzene with concentrated mixed acids is a fast and highly exothermic process, which suffers from considerable mass transfer resistance and poor heat transfer rates. The reaction kinetics has not been thoroughly reported before. In this work, a continuous‐flow microreactor system and a homogeneous reaction condition were proposed to obtain accurate chlorobenzene nitration kinetics parameters at high mixed acid concentrations. A general model for predicting the observed reaction rate constants was established. With a new method for estimating the equilibria associated with HNO3 in aqueous sulfuric acid, the rate constants based on nitronium ion and activation energies were obtained. Compared with batch reactors, the continuous‐flow microreactor system allows for a sufficient heat transfer efficiency and accurate residence time control, making it possible to study the reaction performance more quickly and sensitively. This work may provide a reliable reference for the kinetic study of similar processes.

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ChemInform Abstract: THE M(C) ACTIVITY COEFFICIENT FUNCTION FOR ACID‐BASE EQUILIBRIA PART 1, NEW METHODS FOR ESTIMATING PK(A) VALUES FOR WEAK BASES

Cited by 4 publications

References 1 publication

Nitration of nitrobenzene at high‐concentrations of sulfuric acid: Mass transfer and kinetic aspects

Nitration of nitrobenzene at high‐concentrations of sulfuric acid: Mass transfer and kinetic aspects

Continuous flow nitration of 3-[2-chloro-4-(trifluoromethyl) phenoxy] benzoic acid and its chemical kinetics within droplet-based microreactors

Determination of the kinetics of chlorobenzene nitration using a homogeneously continuous microflow

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