Vorrichtung und Verfahren zur Bestimmung von Zeta-Potential und Grenzflächenleitfähigkeit

• Main Authors: ZIMMERMANN, RALF, JENSCHKE, WOLFGANG, WERNER, CARSTEN, KOERBER, HEINZ
• Format: Patent
• Language: German
• Published: 11.03.2004
• Edition: 7
• Subjects: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; PHYSICS; TESTING

An assembly determines the Zeta potential and surface boundary layer conductivity of a colloidal sample. The assembly has a measuring cell. The cell is both preceded and followed respectively by a liquid container also containing space for gas. The containers are linked by a fluid loop circulation tube discharging from the base of one container into the gas space of the other. The fluid containers are further linked with each other via a circuit loop with shut-off valves. An Independent claim is included for a process, in which fluid circulates between all containers and the measuring cell, and in which the measurement circulation loop is simultaneously or subsequently opened. Following the opening, the liquid container circulation loop is closed and the sample is passed through the measuring cell. The tubes to the measuring cell and each fluid container have volumetric flow sensors. The liquid container loop incorporates a dosing cell. The liquid container loop incorporates ion-selective electrodes, conductivity measuring cells, temperature sensors and other components which register selected process parameters. The parameters include pH, ion concentration, specific conductivity and temperature. Liquid flow is induced in the measuring cell by gas pressure introduced at one point and a bleed valve elsewhere in another container.