DT-1202 and DT-1210 are acoustic measuring devices that combine acoustic spectrometry for particle size measurement (ISO 20998-1) and electroacoustics for zeta potential determination (ISO 13099-1 and -3).
For particle size measurement, the dispersion to be characterized is measured in 180° transmission with regard to ultrasonic attenuation between an ultrasonic transmitter and detector within a sound frequency spectrum of 1-100 MHz. The particle size distribution is then calculated from the measured attenuation spectrum. A special feature of acoustic spectrometry (DT series) is the multigap technique, i.e. the spectrum is measured at several transmitter-detector gaps in order to obtain more precise measurement data and also to cover the widest possible concentration range (0.1 – 60 vol.%). The DT-1202/DT-1210 can therefore be used to characterize original concentrated suspensions, emulsions or even pastes with regard to particle size.
The zeta potential measurement is carried out using the very flexible zeta probe in a beaker or process vessel as required. 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 with the zeta probe as a micro colloidal vibration current (CVI method). The zeta potential is determined from this using the DT software. As with particle size, this technique can also 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. The combination measuring cell of the DT-1202 makes simultaneous measurement of particle size and zeta potential – even in conjunction with pH or additive titration experiments, for example – no problem!
DT-1202 has a rigid particle size measuring chamber that is resistant to almost all solvents and requires a minimum sample volume of 15 ml (in the case of a sample that is stable over the measuring cycle, i.e. no stirring or pumping is required). If the sample tends to destabilize, either the device’s integrated magnetic stirrer or, for higher viscosity systems, a peristaltic pump with a correspondingly larger sample volume (> 70 ml) can be used. The integrated zeta probe can be used flexibly in external vessels or in the combination measuring cell together with the particle size measurement.
DT-1210 is the low-volume version of the DT-1202 for particle size determination: Equipped with a flexible silicone measuring cell that is easy to remove, it only requires a volume of approx. 5 ml for stable samples. The use of a peristaltic pump (volume approx. 20-25 ml) is also possible for unstable systems. In addition, the measuring cell is very easy to fill and clean and is therefore ideal for paste-like systems such as battery or color slurries. The integrated zeta probe is identical to the DT-1202 and can be used flexibly in external vessels.
DT-1202 Acoustic attenuation and Electroacoustics, Particle size and zeta potential | DT-1210 Acoustic attenuation and Electroacoustics, Particle size and zeta potential | |
Measured and calculated parameters | ||
Particle size [µm] | 0.001 – 1000 | 0.001 – 1000 |
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% OP | 10-11-101 ± 1% OP |
Temperature [°C]2 | 0-100 ± 0.1% | 0-100 ± 0.1% |
Sound speed [m/sec] | 500-3000 ± 0.1% | 500-3000 ± 0.1% |
Frequency range [MHz] | 1 – 100 | 1 – 100 |
porosity [%] | 1-99 OP | 1-99 OP |
Measurement time | ||
For particle size [min] | 1 – 10 | 1 – 10 |
For zeta potential [min] | 0.5 | 0.5 |
Sample requirements | ||
Particle size sample volume [ml] | ≥ 15 | ≥ 5 |
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
/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 and /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 unit suitable for DT-100/110/1202/1210 consists of a manually operated peristaltic pump, lifting platform, tubing suitable for the suspension and three-way stopcock. It is ideally suited for particle size measurement of sedimenting or highly viscous samples, also in conjunction with titration experiments, to ensure optimum mixing.
This option suitable for DT-100/110/1202/1210 consists of either an oven (RT – 50°C) or refrigerator (approx. 7°C – RT) to measure the sample at the desired temperature (approx. 7° – 50°C) with regard to particle size distribution.
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.
DT-100/ DT-110 | Particle size; Acoustic attenuation spectroscopy 5 nm – 1,000 µm |
Bettersizer S3 Series | Particle size; Laser diffraction and dynamic image analysis 0.01 – 3,500 µm |
Bettersizer 2600 | Particle size; Laser diffraction 0.02 – 2,600 µm |
Bettersizer ST | Particle size; Laser diffraction 0.1 – 1,000 µm |
BeNano Serie | Particle size; Dynamic Light Scattering 0.3 nm – 15 µm Zeta potential; Electrophoretic light scattering; no limitation |
BeVision D2 | Dynamic image analysis 2 µm – 10,000 µm |