Spectrophotometric Determination of Acidity Constants of Alizarine Red S in Mixed Aqueous−Organic Solvents

Ghasemi, Jahan B.; Lotfi, Shahram; Safaeian, Mahbobeh; Ниази, Али; Mazloum-Ardakani, Mohammad; Noroozi, Mohammad

doi:10.1021/je050535d

Cited by 25 publications

(23 citation statements)

References 41 publications

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“…Walnut shell composition is very similar to that of other wood biomass because cellulose, hemicellulose, and lignin are the main components. [60][61][62][63][64][65][66] Various methods have been suggested for the hydrolysis of cellulose and hemicellulose in wood biomass as a means of producing carbohydrates, which are good sources for the production of bioethanol. 59 Another effective method for the utilization of walnut shells is the production of charcoal and activated carbon by executing pyrolysis.…”

Section: Walnut Shellmentioning

confidence: 99%

Walnut (Juglans regiaL.) shell pyroligneous acid: chemical constituents and functional applications

Jahanban-Esfahlan

Amarowicz

2018

RSC Adv.

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Upon the processing of different agricultural products, considerable amounts of by-products and biowastes are produced and discarded or burnt as fuel, which are a potential source of valuable compounds. Over the past several decades, plant by-products have been recognized as a source of nutraceutical components, including dietary fibers, phenolics, and many other useful compounds. The walnut is known as an important tree nut. The shell of a walnut is the middle part of the fruit and it is a waste product of walnut processing industries. Recently, pyroligneous acids from the walnut shell have been receiving much-increasing interest because of their excellent antimicrobial and antioxidant activities. Hence, this review deals with the recent scientific literature on walnut shell pyroligneous acids and their chemical composition as well as their functional applications.a Collected at three temperature ranges by GC-MS. b Collected at seven temperature ranges by GC-MS. c 5% NaHCO 3 extract (OA 5 ) and 4% NaOH extract (P 3 ).This journal is a Collected at three temperature ranges by GC-MS. b Collected at seven temperature ranges by GC-MS. c 5% NaHCO 3 extract (OA 5 ) and 4% NaOH extract (P 3 ). Fig. 2 The chemical structures of organic acids identified in walnut shell pyroligneous acids.This journal is a Collected at three temperature ranges by GC-MS. b Collected at seven temperature ranges by GC-MS. c 5% NaHCO 3 extract (OA 5 ) and 4% NaOH extract (P 3 ).22382 | RSC Adv., 2018,8,[22376][22377][22378][22379][22380][22381][22382][22383][22384][22385][22386][22387][22388][22389][22390][22391] This journal is a Collected at three temperature ranges by GC-MS. b Collected at seven temperature ranges by GC-MS. c 5% NaHCO 3 extract (OA 5 ) and 4% NaOH extract (P 3 ).

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Section: Walnut Shellmentioning

confidence: 99%

Walnut (Juglans regiaL.) shell pyroligneous acid: chemical constituents and functional applications

Jahanban-Esfahlan

Amarowicz

2018

RSC Adv.

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“…Relatively high amounts of BDNF compared to BDAF and BBDMAF were dissolved in 50% EtOH to dissociate the absorption bands of the monoanionic and dianionic forms, as previously reported for DNF [ 14 ]. The UV‒Vis absorption spectra and pH-dependent mole fractions of each protolytic species of BDNF , BDAF , and BBDMAF were predicted and their p K a values were determined through the DATAN program analysis ( Figure 3 and Table 1 ) [ 15 , 16 , 17 ].…”

Section: Resultsmentioning

confidence: 99%

“…The fluorescence quantum yields ( Φ F ) were determined using a 0.1-M aqueous NaOH solution of fluorescein as a standard [ 23 ]. The p K a values were determined by the DATAN program, using the physical constraints approach [ 15 , 16 , 17 ].…”

Section: Methodsmentioning

confidence: 99%

5-Bromo-4′,5′-bis(dimethylamino)fluorescein: Synthesis and Photophysical Studies

et al. 2018

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In this study, three new fluorescein derivatives—5-bromo-4′,5′-dinitrofluorescein (BDNF), 5-bromo-4′,5′-diaminofluorescein (BDAF), and 5-bromo-4′,5′-bis(dimethylamino)fluorescein (BBDMAF)—were synthesized and their pH-dependent protolytic equilibria were investigated. In particular, BBDMAF exhibited pH-dependent fluorescence, showing strong emission only at pH 3–6. BBDMAF bears a bromine moiety and thus, can be used in various cross-coupling reactions to prepare derivatives and take advantage of its unique emission properties. To confirm this, the Suzuki and Sonogashira reactions of BBDMAF with phenylboronic acid and phenylacetylene, respectively, were performed, and the desired products were successfully obtained.

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“…The only problem lies in determining the dissociation constants of the indicator in the specific nonaqueous or mixed solvent. Although scarce, the thermodynamic equilibrium constants in mixed solvents have been reported for the following indicator dyes: antraquinones and anthrones in MeOH + H 2 O (Almasifar et al, 1997;Shamsipur et al, 1993), alizarine red s in MeOH +, EtOH +, DMSO + and AN + H 2 O (Ghasemi et al, 2006b), 4-(2-pyridylazo)resorcinol in MeOH + H 2 O (Ghasemi et al, 2002), in AN + H 2 O (Ghasemi et al, 2003), in DMF + H 2 O (Rouhollahi et al, 2005), and in dioxane + H 2 O (Ghasemi et al, 2006a), methyl red and phenol red in EtOH + and MeOH + H 2 O (Srour and McDonald, 2008b), and fluorescein in EtOH + H 2 O (Gholivand et al, 2008). …”

Section: -Prohmentioning

confidence: 99%

Solution Properties of Inorganic Contamination in Mixed Solvents: Theory, Progress, and Limitations

Srour¹,

McDonald

2011

Critical Reviews in Environmental Science and Technology

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Most of what is known about the environmental fate and transport of contaminants comes from studies of dilute, aqueous solutions. Theoretical and practical aspects of hydrophobic organic contaminants in aqueous mixtures of organic solvents are well developed, but relatively little attention has been paid to those situations where inorganic contaminants such as metals, water, and organic solvents occur simultaneously. The authors discuss changes in solution properties accompanying the addition of organic solvents. They review more than 500 references to available data on ion solvation, solubility, activity, acidity, pairing, and pH in electrolyte and electrolyte-free solvent mixtures and tabulate selected experimental values. Whenever available, equations developed to estimate these properties are given and their applications and limitations described. The implications of the progress in mixed-solvents solution chemistry on contaminant behavior and transport are described. Major limitations to the study of inorganic contamination in mixed solvents include the absence of complete and comprehensive data (e.g., type of ionic species, activity coefficients, solubility constants) that characterize solute and solvent properties in these mixtures and the indefinite number of possible solute and solvent combinations. The generation of models predicting such data from easily measured benchmark solute and solvent properties is a major challenge. The availability of such database and models may open the field for environmental engineers and soil scientists to study the basic chemical processes and mechanisms of metal contamination in complex multicomponent systems.

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Spectrophotometric Determination of Acidity Constants of Alizarine Red S in Mixed Aqueous−Organic Solvents

Cited by 25 publications

References 41 publications

Walnut (Juglans regiaL.) shell pyroligneous acid: chemical constituents and functional applications

Walnut (Juglans regiaL.) shell pyroligneous acid: chemical constituents and functional applications

5-Bromo-4′,5′-bis(dimethylamino)fluorescein: Synthesis and Photophysical Studies

Solution Properties of Inorganic Contamination in Mixed Solvents: Theory, Progress, and Limitations

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