DT-300, DT-310 and DT-330 are zeta potential measurement devices that work according to the principle of electroacoustics (ISO 13099-1 und -3). With all three device types, the characterization of suspensions and emulsions concentrated up to 60 % by volume is possible without any problems for stable systems at rest and for non-stable systems under stirring or pumping. Depending on the configuration, automatic titration experiments (e.g. in dependence of the pH value or additive quantity) can also be carried out or zeta potentials of solid (porous) sediments and monolithic, porous systems such as geological cores, ceramic tiles etc. can be performed.
DT-300
DT-310
DT-330
The zeta potential measurement on dispersions is carried out using the very flexible zeta probe in a beaker or process vessel as required on the basis of the CVI methode (CVI = Colloidal Vibration Current(I)). The probe couples in an ultrasonic wave pulse directly into the dispersion to be measured. This causes the particles to move relative to the surrounding medium, resulting in a (frequent) displacement of the charged particle towards its diffuse double layer. This creates short-term dipoles, which in turn are detected by the zeta probe as a colloidal micro alternating current. The zeta potential is determined from this via the DT software. This technique can be used to characterize original concentrated dispersions. Thanks to this innovative probe technology (pulse-echo method with a smooth surface), the zeta potential can be used very flexibly on a laboratory scale or in a process. In addition, further colloid chemical parameters such as DEBYE length, κa value, DUKHIN’s number and surface charge density in the case of strongly non-polar solvents can be determined by additionally measuring the electrical conductivity.
The zeta potential of solid (porous) sediments or monolithic, porous systems is determined using the zeta probe (CVI method) in conjunction with the high-frequency conductivity probe for aqueous systems (see accessories below). The latter is used to determine the porosity of the sample to be characterized and then, if this value is known, to determine the zeta potential on the basis of the seismo-electric effect.
DT-300 is the basic device for determining the zeta potential in concentrated suspensions and emulsions (0.1 – 60 vol.%) using the CVI zeta probe as a function of the pH value. Optionally, the system can also be used for the colloid chemical characterization of systems in polar and non-polar solvents. The measurement can be performed by stirring in a beaker or by pumping the dispersion. The supplied small volume cell is suitable for quiescent, stable systems that are only available in small volumes (>0.1 ml).
DT-310 is the zeta potential measurement device based on the DT-300 and equipped by default for all applications (aqueous, polar and non-polar dispersions). Automatic pH or additive titration is no problem thanks to the 2-burette auto titrator included in the scope of delivery.
DT-330 is also based on the DT-300 and offers by default software-based zeta potential determination on (porous) sediments as well as porous monolithic samples based on the Seismo-Electric Effect, equipped as standard with the high-frequency conductivity probe.
DT-300, DT-310 Electroacoustics, Zeta potential | DT-330 Electroacoustics, Zeta potential | |
Measured and calculated parameters | ||
Zeta potential [mV] | -200 – 200 ± 0.1 | -200 – 200 ± 0.1 |
pH | 0.5-13.5 ± 0.1 | 0.5-13.5 ± 0.1 |
Electric conductivity [S/m]1 | 10-11– 101 ± 1% OP3 | 10-4– 101 ± 1% 10-11– 101 ± 1% OP |
Temperature [°C]2 | 0-100 ± 0.1% | 0-100 ± 0.1% |
Frequency range [MHz] | 1 – 100 | 1 – 100 |
porosity [%] | – | 1-99 |
Measurement time | ||
For zeta potential [min] | 0.5 | 0.5 |
Sample requirements | ||
Zeta potential sample volume [ml] | ≥ 0.1 | ≥ 0.1 |
Concentration [vol.-%] | 0.1 – 60 | 0.1 – 60 |
Temperature [°C] | 7 – 50 | 7 – 50 |
Viscosity of medium and colloid [cp] | ≤ 20000 | ≤ 20000 |
1only in combination with DT-700
2Temperature probe can measure up to 100°C, permissible dispersion temperature in the device ≥ 7°C and ≤ 50°C
3OP = Optionally available
/1/ ISO 20998-1 Measurement and characterization of particles by acoustic methods.
/2/ A. Dukhin, P. Goetz: Characterization of Liquids, Nano- and Microparticulates, and Porous Bodies using Ultrasound. 2nd Edition. Oxford: Elsevier, 2010.
/3/ Broschure DT Series: Particle size and zeta potential using acoustic and electroacoustic Spectrometry
/4/ PARTICLE WORLD 19; p. 18 – 19; “Characterization of liquids, dispersions, emulsions and porous materials using ultrasound”.
The autotitrator suitable for DT-100/110/300/310/330/1202/1210 is an ideal tool for determining the particle size and/or the zeta potential as a function of the pH value or a defined amount of additive. It is equipped with two high-precision titration pumps that perform a predefined titration protocol under software control. Both low-viscosity and high-viscosity (> 3000 cp) titrants can be used.
This probe suitable for DT-100/110/300/310/330/1202 and /1210 is perfect for automatically measuring the electrical conductivity of aqueous liquids and dispersions. It is connected directly to the control box of the measuring device and controlled via its software (no stand-alone measuring device).
This stand-alone measuring probe is perfectly suited for the automatic measurement of the electrical conductivity of organic liquids and dispersions. It is available as a stand-alone measuring device (DT-700).
This measuring stand suitable for DT-300/310/330/1202/1210 is especially designed for the zeta potential measurement of highly viscous systems such as cement, battery or ceramic suspensions. Even the automated determination of the isoelectric point of such highly concentrated, paste-like systems is possible by using the laboratory stirrer and continuous mixing.
This stand-alone measuring device is designed to determine the electrical permittivity (dielectricity) of aqueous liquids, polar and non-polar solvents. Two measuring ranges, 1-20 and 1-200 with coarse and fine adjustment, enable a very precise determination of this parameter.
BeNano series | Zeta potential; Electrophoretic light scattering; no limitation |