Sample dispersion method before particle size distribtion test

In order to obtain correct data of particle size analysis, It is necessary to open the agglomerated particles aggregate during the particle size analysis, keep particles uniformly dispersed in the monomer and medium, this operation is called a "dispersion."Particle size analyzer dispersion system required disperse particle not segregation.

When particle is in the liquid medium, Wet dispersion techniques are as below:

1) Ultrasonic dispersion,

With unique characteristics and sound cavitation spreading in the liquid,

Ultrasonic wave will make the aggregates disperse well.

2) Mechanically stirred dispersion,

The use of mechanical action of the rotating blades, make particles disperse well and distributed uniformly in the container;

3) Liquid circulation,

Pump drive suspension flow in the high speed,

Make particles disperse uniformly through the full dispersion system to prevent large particles from settling.

4) Dispersants, some samples require chemical dispersion method to disperse, adding an appropriate amount of dispersing agent to improve the electrical properties of the particle surface to maintain the dispersed state.

5) Sample Surface preparation,

some samples are not compatible to medium, such as floating in the water, you need to add a small amount of ethanol or other surface treatment agent to pre-treat the samples before entering the water, so as to disperse well in the water.

Dry dispersion technology

Applications: materials occurs chemical reaction in water, or shape change in the liquid.

1) Vibrate Feeding and Full built-in dispersion system,and normal shock shearing effect make particles sufficient dispersion, adopt wearable ceramics improve dispersion system's working life.

2)The use of High-speed air flow generate negative pressure, It will suck the dry powders into the dispersion pump mixed with the gas stream.

3) High speed air flow is turbulence also, Particles are effected by complex Hydromechanics in the turbulence, including positive impact shock, shearing between the whirling airflow, the Coanda effect of particles and particle collisions etc., make agglomerated particles broken down into monomers achieve dispersion purposes.

Particles dispersion note:

Firstly, need know particles character.

Fragile particles need carefully disperse, such as glass beads, coal powders; particle after surface treatment can't use ultrasonic dispersion;

If need observe the original natural state of the material, It can't be dispersed; If need record crystallization or other chemical reaction processesof particle, do not disperse.