Untitled

Cherif, Mourad; Mgaidi, Arbi; Ammar, Naceur; Vallée, Géraldine; Fürst, Walter

doi:10.1023/a:1005150400746

Cited by 53 publications

(31 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In Fig. 4, one shows that in the case of the second mechanism, the actual approach permits to represent the experimental values of the undissociated H 3 One concludes that the mechanisms (i and ii) give a contradictory results, but are, respectively, in agreement with the experimental data of Preston and Adams [23] and Cherif et al [24]. To use one of the two mechanisms for calculation of speciation, it is necessary to eliminate the contradiction between these experimental data by another work aiming to a better identification of the species present in the system H 3 PO 4 -H 2 O.…”

Section: Resultssupporting

confidence: 64%

“…To validate the electrolyte-NRTL model, one uses the speciation measurements of the system H 3 PO 4 -H 2 O determined by Preston and Adams [23] and by Cherif et al [24]. The two studies are based on the Raman Spectroscopy and differ in the number of identified species.…”

Section: Databasementioning

confidence: 99%

“…The two studies are based on the Raman Spectroscopy and differ in the number of identified species. Preston and Adams identified only the species that appear in the first dissociation of H 3 PO 4 , whereas the measurements of Cherif et al [24] concern the concentration of the various species including H 5 P 2 O 8 − . This database contains in addition the pH data of phosphoric acid solutions measured by Elmore et al [16] in concentration range 0.1-10 mol kg −1 , the data determined by Elmore al.…”

Section: Databasementioning

confidence: 99%

See 2 more Smart Citations

Modeling of excess properties and vapor–liquid equilibrium of the system H3PO4–H2O

Messnaoui

Bounahmidi

2005

Fluid Phase Equilibria

View full text Add to dashboard Cite

Section: Resultssupporting

confidence: 64%

Section: Databasementioning

confidence: 99%

Section: Databasementioning

confidence: 99%

See 1 more Smart Citation

Modeling of excess properties and vapor–liquid equilibrium of the system H3PO4–H2O

Messnaoui

Bounahmidi

2005

Fluid Phase Equilibria

View full text Add to dashboard Cite

“…1,2) Moreover, in spite of its high viscosity, liquid phosphoric acid has high proton conductivity, which makes it useful as fuel cell electrolytes. Therefore, many experimental and theoretical studies have been carried out on the liquid phase [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] as well as on the monomer [21][22][23] ( Fig. 1), crystal, [24][25][26] and the polymeric gels [27][28][29][30] of phosphoric acid.…”

Section: Introductionmentioning

confidence: 99%

Ab InitioMolecular-Dynamics Simulation of Concentrated Phosphoric Acid

Tsuchida

2006

J. Phys. Soc. Jpn.

View full text Add to dashboard Cite

We have investigated the properties of 100% phosphoric acid (H 3 PO 4 ) in the liquid state by the combination of gradient-corrected density-functional theory and norm-conserving pseudopotentials. Various structural properties as well as the vibrational density of states have been calculated through molecular-dynamics simulations under the Born-Oppenheimer approximation. Proton transfer is found to occur frequently between adjacent PO 4 groups along the OH···O hydrogen bonds, which makes the single and double bonds indistinguishable.

show abstract

“…An analogous signal is evident in the Raman spectrum of bulk aqueous phosphoric acid [46][47][48]. The most intense Raman band of bulk aqueous phosphoric acid is located between 840 and 960 cm À1 and is caused by stretching vibrations mðPðÀOHÞ 3 Þ of H 3 PO 4 molecules and mðPðÀOHÞ 2 Þ of H 2 PO À 4 ions.…”

Section: Raman Spectramentioning

confidence: 85%

Uptake of protic electrolytes by polybenzimidazole-type polymers: absorption isotherms and electrolyte/polymer interactions

Korte¹,

Conti

Wackerl³

et al. 2015

J Appl Electrochem

View full text Add to dashboard Cite

Polybenzimidazole (PBI) membranes doped with phosphoric acid are used as proton-conducting membrane in high-temperature polymer electrolyte fuel cells. There is no general model for the thermodynamics of the absorption process over the whole accessible doping range for all published data. The interactions between H 3 PO 4 and polymer chains, the polycondensation equilibria of H 3 PO 4 and the implications on proton conductivity are still largely unknown. In this study, we demonstrate that the uptake of a protic electrolyte by a polymer with basic moieties, i.e. a PBI-type polymer, can be described satisfactorily with a BET-like absorption isotherm. The absorption equilibria of the uptake process are analysed using literature data on the H 3 PO 4 , H 2 SO 4 and HClO 4 uptake of non-crosslinked m-PBI and AB-PBI as well as using our own investigations on the H 3 PO 4 uptake of a commercial crosslinked PBI derivative, Fumapem AM-55. In addition to the thermodynamic data of the absorption process, Raman data on m-PBI taken from the literature and our own Raman investigations on Fumapem AM-55 are taken into account. It is possible to correlate domains in the absorption isotherms with specific features in the Raman spectra. Two stages for the uptake of a protic electrolyte can be distinguished: (i) the protonation of the polymer chains and thus coulombic interactions with the electrolyte anions, (ii) the formation of H bonds directly with the chains and with electrolyte molecules that are still absorbed.

show abstract

Untitled

Cited by 53 publications

References 7 publications

Modeling of excess properties and vapor–liquid equilibrium of the system H3PO4–H2O

Modeling of excess properties and vapor–liquid equilibrium of the system H3PO4–H2O

Ab InitioMolecular-Dynamics Simulation of Concentrated Phosphoric Acid

Uptake of protic electrolytes by polybenzimidazole-type polymers: absorption isotherms and electrolyte/polymer interactions

Contact Info

Product

Resources

About