A Brief on Lab Homogenizer Applications

The term “homogenizing” covers a variety of processes that simply defined means blending materials that may or may not be compatible.  A common example is homogenized milk.  It is homogenized to provide even consistency by dispersing the heavier cream into the more liquid milk to and prevent separation during storage.

A much broader definition relates to mixing challenges that cannot be accomplished using the best stirring methods available.  In these instances the term homogenizing can include related processing steps such as emulsifying, dispersing, dissolving, and disintegrating solid, liquid or gaseous phase media into other media.

At CAT Scientific we use the term dispersing to define how equipment can be employed for homogenizing. The equipment we recommend for most lab and pilot plant applications is the CAT homogenizer system, its drive units, and the variety of homogenizing rotor-stator configurations together called homogenizer generators.   We identify three forms of the catch-all term dispersing:

• Gas into a liquid to produce foam
• Solids into a liquid such as pigments in paints and lacquers
• Processing immiscible liquids such as oil and water

Cell disruption and tissue preparation are examples of biological applications for these tools.

How Homogenizers Work

The bottom of the rotor shaft that is attached to the drive motor is machined to sharp edges to compliment the stationary stator fixed to the drive motor housing.  The base of the stator is likewise machined with sharp edges.  As the material is drawn up into the generator assembly and into the working area between the rotor and stator it is subjected to a combination of mechanical shearing and sonic energy that homogenize the material.

Rotor and stator generator components are produced in sizes to process materials in containers ranging from test tubes to 20 liter beakers.   They are designed to handle or perform specific functions based on the type of samples being processed.  Examples include viscous or coarse samples, low viscosity materials, aqueous media and knife edges for cutting applications.

Rotor-stator assemblies are interchangeable using the supplied rotor wrench allowing researchers to perform multiple dispersion experiments using the same drive motor.  Drive motor are available in several power ratings in watts with selection governed by the volume and physical characteristics of the material being processed.  These variable speed motors should be started at the lowest RPM and ramped to the desired speed to help avoid splashing samples out of the container.  All drive motors except those designed to be hand held should be firmly attached to an adjustable  mounting system to hold them steady in the beaker or flask.

Special Attachments

Other applications for lab homogenizers are performed using special attachments to pulverize solid samples for further processing and to provide closed loop or in line processing.  The former is handled by the AX 60 grinding mill and the latter by encasing the rotor-stator configuration in one of two flow-through chamber models.   These accessories should be used with higher power drive motors such as the X1000.

If you are considering the purchase of a lab homogenizer help us help you in making the correct decision.  You can do this by filling out our homogenizer questionnaire and faxing it to us.  We’ll get back to you as soon as we can with some suggestions.