In BUT, the instrument is used for the rapid, reliable and repeatable measurement of material particle size, from 10 nm to millimetres. Particles can be measured in suspensions, emulsions or loose material.
The instrument can be used for measuring the quality of samples during operational checks and it is perfectly suited for tasks in research and development.
The instrument consists of a central measuring unit and dispersing module, which can be promptly and easily replaced. The central measuring unit contains two semiconductor lasers, each of a capacity of 7 mW and wavelengths of 532 nm and 940 nm. The total range for measuring particle sizes is within 0.08 – 2000 µm. An ultrasound bath, built into the unit for wet dispersing has a capacity of up to 50 Watt and vibrates liquid at 40 kHz.
Microtec was thus designed in a modular fashion for measuring wet and dry dispersions. The quality of measurement in the wet dispersing unit depends on the good dispersion of particles in the measuring chamber, which is achieved using programmable ultrasound. Thus precise dispersion of particles can be achieved and measurements can be taken of extremely complex samples of materials. In the case of loose mixtures, the instrument can work with a material sample of a volume smaller than 1 cm2. The sample is dosed automatically and dispersed under pressure in a Venturi tube.
The instrument is comfortable and easy to use and measurement results are excellent.
The image on the left illustrates the concept of the beam screening method. In the top part there is no sample, therefore there is no dispersion. Intensity detected by the photodiode is now 100 %. When the measured sample is added, the laser beam scatters. When the sample is added, thanks to the process of dispersion, the intensity detected by the photodiode decreases below the value of 100 % - the beam screening.
Analyser of particle size FRITSCH
Analysette 22 - MicroTec plus
> measuring range 0.08 to 2000 um
> max. resolution – up to 108 measuring channels
> approximate amount of sample: 0.1-2 cm3 in 500 ml of liquid (wet), 5-50 cm3 (dry)
> fully automatic course of measurement
> high reproducibility
> automatic calibration
> solid measuring cell
> phase interface for optional individual programming
> detector on a stable ceramic carrier
> 521 nm Laserdioda for fine particles
> 940 nm double-strand Laserdioda for coarse particles
> calibration capacity according to ISO 9001:2000
> compliance with standard ISO 13320-1 (Laser Diffraction)
Dispersing unit for wet measurement
> Sample volume [ml] 300-500
> Energy and frequency of ultrasound 60 W / 36 kHz
> Pump capacity [l/min.] 5.5
> Depth of measurement level in laser beam [mm] 4
> Max. particle size [µm] 2000
> Max. specific gravity of sample [g/cm3] 14
> Materials of the instrument coming into contact with the sample: stainless-steel, Viton, Glass, PTFE
