Measurement of pH in subcritical and supercritical aqueous systems

Macdonald, Digby D.; Hettiarachchi, S.; Song, Herking; Mäkelä, Kari; Emerson, R.; Ben-Haim, Mordehai

doi:10.1007/bf00651512

Cited by 75 publications

(41 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…They carried out high quality potentiometric measurements (accuracy from 3 to 10 mV) using a flow-through technique along with a flow-through external pressure-balanced Ag/AgCl reference electrode (EPBRE) in which the electroactive element is maintained at room temperature via a non-isothermal electrolyte bridge [118] thereby overcoming the problem with the value of the thermal liquid junction potentials varying AE 150 mV depending on the nature of the electrolyte bridge and the thermal gradient across it. Other pH sensing electrodes that they have successfully developed include a tungsten oxide [122], glass electrodes for moderately high temperature (200 ± 250 8C) [119], and a YZS (yttrium-stabilized zirconia) pH sensitive membrane electrode [120,121] containing a Hg/HgO internal element fitted into an autoclave contained in a once through/recirculating flow loop that operates in a single-phase mode at both sub and supercritical temperatures (temperatures from 200 and 390 8C and pressure of 255 bar). They also developed Pd-Pt electrodes for measuring dissolved H 2 in supercritical media [123].…”

Section: Voltammetry At High Temperatures and High Pressuresmentioning

confidence: 99%

Electrochemistry at High Pressures: A Review

2004

View full text Add to dashboard Cite

High pressure electrochemical studies are potentially dangerous and less immediately implemented than conventional investigations. Technical obstacles related to properties of the working electrode material, preparation of its surface, availability of suitable reference electrodes, and the need for specially designed high pressure equipment and cells may account for the relative lack of experimental data on electrochemistry at high pressures. However, despite the stringent requirements for system and equipment stability, significant developments have been made in recent years and the combination of electrochemical methods with high hydrostatic pressure has provided useful insights into the thermodynamics, kinetics, and other physico-chemical characteristics of a wide range of redox reactions. In addition to fundamental information, high pressure electrochemistry has also lead to a better understanding of a variety of processes under non-classical conditions with potential applications in today×s industrial environment from extraction and electrosynthesis in supercritical fluids to measurement of the pH at the bottom of the ocean. The purpose of this article is to detail the experimental pressurizing apparatus for electroanalytical measurements at high pressures and to review the relevant literature on the effect of pressure on electrode processes and on the properties of aqueous electrolyte solutions.

show abstract

Section: Voltammetry At High Temperatures and High Pressuresmentioning

confidence: 99%

Electrochemistry at High Pressures: A Review

2004

View full text Add to dashboard Cite

show abstract

“…Between 250 and 320°C, the pH was determined with an external pressure balanced reference electrode Ag/AgCl/10 À3 M KCl (EPBRE) and an yttrium stabilized zirconia pH electrode filled with Cu/Cu 2 O as internal Ref. [11][12][13]. Acetic acid/sodium acetate (0.01 mol kg À1 /0.01 mol kg À1 ) and disodium tetraborate …”

Section: Mass Titrationmentioning

confidence: 99%

Characterization of the surface charge of oxide particles of PWR primary water circuits from 5 to 320°C

Barale¹,

Mansour²,

Carrette³

et al. 2008

Journal of Nuclear Materials

View full text Add to dashboard Cite

“…At present, high-temperature measurements of pH are successfully performed in experimental geochemistry using a glass electrode up to 175 ° C (Kryukov et al, 1966) and a hydrogen electrode up to 320 ° C (Mesmer et al, 1988(Mesmer et al, , 1995Macdonald et al, 1992). Moreover, using a pH-sensitive electrode made of a ZrO 2 ceramic and stabilized with Y 2 O 3 , it has become feasible to raise the temperature of measurements to 400-450 ° C. The state of the art of measurement techniques with yttria-stabilized zirconia sensors was reviewed by Lvov et al (2003).…”

Section: Introductionmentioning

confidence: 98%

Determination of the HCl dissociation constant at a temperature of 350°C and 200 bars of pressure by the potentiometric method using a ceramic electrode

Reukov

Зотов

2006

Geol. Ore Deposits

View full text Add to dashboard Cite

A technique has been developed for pH measurement in flow-through cells at temperatures from 175 to 350 ° C and pressures up to 350 bars in a nonisothermal cell consisting of a ZrO 2 (Y 2 O 3 ) ceramic electrode and a Ag/AgCl (2 M KCl, 25 ° C) flow-through reference electrode. This technique has been applied to determination of the HCl dissociation constant at 350 ° C and 200 bars; previously, the HCl dissociation has not been studied sufficiently reliably under these conditions. The obtained value p K dis = 2.16 ± 0.03 was used to estimate the acidity of fluids from their chemical composition at the vent of high-temperature submarine hydrothermal solutions.

show abstract

Measurement of pH in subcritical and supercritical aqueous systems

Cited by 75 publications

References 16 publications

Electrochemistry at High Pressures: A Review

Electrochemistry at High Pressures: A Review

Characterization of the surface charge of oxide particles of PWR primary water circuits from 5 to 320°C

Determination of the HCl dissociation constant at a temperature of 350°C and 200 bars of pressure by the potentiometric method using a ceramic electrode

Contact Info

Product

Resources

About