pH Measurements with a Glass Electrode Withstanding 1500 kg/cm2 Hydrostatic Pressure

Abstract

A glass electrode can be made to withstand high hydrostatic pressure, up to 1500 kg/cm2, by separating the inside fluid from the outside one with a layer of silicone oil acting as a liquid piston, enabling the inside and outside pressure to compensate continuously. Such a glass electrode, with two Ag–AgCl electrodes, maintains its hydrogen electrode function at high pressure. pH changes resulting from dissociation constant shifts caused by pressure in acid and buffer solutions have been measured in good agreement with theoretical expected values for HCl, acetic acid, carbonic acid, and acetate buffer. No agreement was found for bicarbonate buffer. Phosphate buffer and sea water have also been tested. An adapted version of the cell-assembly is planned to equip the French bathyscaphe for deep-sea investigations.

Electro-mechanical properties of human erythrocyte membranes: The pressure-dependence of potassium permeability

“…Whereas a temperature increase in the oil layer of about 15~ at maximum pressure (100 MPa) and maximum duration (40min) was measured, only an increase of 2~ could be recorded in the solution phase. This finding is in agreement with results reported by Dist6che [8]. Thus, temperature changes cannot account for the observed effects.…”

Electrochemistry at High Pressures: A Review

“…j AgCl j Ag cell [51] and other measurements [72,73]. These findings by Diste ¡ che helped in the development of a glass electrode to measure the pH of sea water [50,68].…”

Impact of dissociation equilibrium shift on bacterial spore inactivation by heat and pressure

“…During the first phase of such basic inactivation studies buffer systems to obtain constant pH-values and medium properties are in common use. However, the dissociation equilibrium in water and buffer solutions varies with pressure and temperature (Bruins, Matser, Janssen, & Boom, 2007;Distèche, 1959;Hamann, 1982;Kitamura & Itoh, 1987;Marshall & Franck, 1981;North, 1973;Quinlan & Reinhart, 2005). This change of the pK a -value plays a major role in different sensitive reactions, but its behaviour has rarely been investigated.…”

“…This change of the pK a -value plays a major role in different sensitive reactions, but its behaviour has rarely been investigated. Distèche (1959) developed one of the first pH electrodes up to 150 MPa. At present only few optical measurement methods during pressure treatment up to 250 MPa (Hayert, Perrier-Cornet, & Gervais, 1999;Quinlan & Reinhart, 2005) and 450 MPa (Stippl, Delgado, & Becker, 2002, 2004 were developed.…”