It depends much on the characteristics of the material being dispersed. Mostly the surface area available, the surface tension properties of the materials and the rheology.

In my opinion, the easiest dispesion processes are done with high shear mixers. They are simple, easy to maintain and with a disciplined sequence are very repeatable.

For processes that require more work I like to use some type of media and a recirculating mill. There are some combinations of media and impeller systems that do a very good job in dispersion work.

Contact me if you need more information.

Antonio Reis

www.vitrom.com ■

Not sure if you got your answer but if you need equipment for this we have everything that you need with dispersion. ■

Originally Posted by Paul A. Webb - Micromeritics, USA

What is the best general approach to dispersing an unknown solid sample in a liquid medium?

The first step I'd to disperse the flow stream to avoid, as far as practical, the globular ion of clusters. The can usually be done with a conical dispersing chute having a deep serrated edge that distributes the powder over a large moving surface. A continuos system reduces the convective demand of the mixing process. The simple application of fundamentals is usually a good approach to such process requirements. ■

This is just another of those threads where the answer is already hovering over the question. Second today in fact.

As a vendor or user of such mixing gear you are hopefully aware of Chemineer classification of pulp stability but failed to specify the degree of pulp stability required.

Furthermore, since pulp stability for an unknown solid in an unspecified liquid requires a degree of experimental work you will perhaps realise that the answer, nearly said solution, is already apparent in the question. The best general approach in this case is the one that works. ■