How to Select a Laboratory Homogenizer
Scientists in research laboratories and pilot plants are often challenged to find ways of processing small or limited-sized samples in the quest to develop then refine procedures leading to production-scale operations. Several tools are available to help in this quest, one of which is called the laboratory homogenizer. This post explains how to select a laboratory homogenizer. You’ll understand
- What laboratory homogenizers do
- Key components of a laboratory homogenizer
- How to operate a lab homogenizer
- Maintaining your laboratory homogenizer
What Laboratory Homogenizers Do
Laboratory and pilot plant homogenizers are designed to perform mixing, blending, stirring, dispersing, disintegrating and emulsifying and similar tasks in research labs, pilot plants and in quality control procedures on production lines.
These versatile tools are often called upon to process samples that, in many cases by their nature, are “resistant” to processing – such as emulsifying as noted just above.
The various tasks require special consideration when selecting a lab homogenizer due to differing physical characteristics of media being processed and the results achieved.
The amount of media being processed in a lab homogenizer must also be taken into consideration. Fortunately, there are several models available to meet differing sample size criteria – ranging from 0.1 mL to 20L as examples.
Key Component of a Lab Homogenizer
The Drive Motor
Homogenizers are produced in several sizes ranging from hand held electrically powered to compressed air powered. The power is delivered by the drive motor. Drive motors are generally selected based on power in terms of watts, and speed in revolutions per minute.
An example of a small lab homogenizer is the X120 hand held model available from CAT Scientific, powered by a 125-watt motor and with adjustable speed from 15,000 to 35,000 rpm. It is a good choice for labs where initial research involves working with sample sizes between 0.1mL and 1L.
At the other end of the scale is the 1700-watt X1740 model also available from CAT Scientific that can process samples from 500mL to 20L. Operating at electronically stabilized speeds from 2500 to 23,000 rpm, its rugged construction and operational versatility makes it an ideal choice for processing cannabis infusions.
If you are working with volatile samples – those posing a danger of fire or explosion in the presence of sparks or other igniters – ask CAT Scientific about air-driven units available for these critical operations.
And as a final note, when selecting your drive motor remember that more power does not necessarily equate to higher speed capability. Selection instead is based on the properties (such as viscosity) and volumes of materials being processed.
The Lab Homogenizer Support System
While the X 120 model mentioned above is described as hand-held, it is recommended that you mount any and all lab homogenizers on a support system for stability and safety.
Laboratory homogenizer support systems generally consist of a stand and vertical rod onto which a vertically adjustable horizontal arm is attached by means of a screw clamp.
The vertically adjustable horizontal arm is firmly affixed to the drive motor housing in such a way that the operator can correctly position the generator (described below) at the correct level in the sample container.
Support stand systems are highly recommended to hold the generator steady. Being hand-held runs the risk of hitting the side of the sample container, risking breakage and sample loss. You can read more about this in the section on how to operate your lab homogenizer.
All CAT homogenizers work on the rotor-stator principle combining mechanical shearing and sonic energy in a way unmatched by other forms of media processing.
Rotors and stators, together called homogenizer generators, are available in several configurations based upon the viscosity of the medium and work being done.
Homogenizer rotors are attached to the rotor shaft using a simple wrench and are powered by the homogenizer drive motor. The shaft is pushed into the drive motor housing until a click is heard signifying that the drive pin is engaged. The sharply machined blades compliment the equally sharp machined slots in the stator.
The homogenizer stator is hand screwed on the rotor shaft tube, in turn firmly attached to the drive motor housing by a holding screw.
CAT Scientific lab homogenizers are capable of accommodating a number of generator configurations. Specification criteria in addition to the above include the length of the rotor shaft and its encasing shaft tube, and the diameter of the generator assembly. Read our paper for a brief description of modular homogenizer systems.
How to Operate Your Lab Homogenizer
Once assembled the homogenizer should be attached to its support system and positioned offset in the sample container to avoid a vortex. Keep the generator at least 10mm above the container bottom and do not start the drive motor until the generator is immersed.
In other words, never run a lab homogenizer generator in open air!
When activating the equipment always start at the lowest RPM then gradually increase speed until the desired RPM is achieved.
The slanted slots in the rotor grasp the medium and forcibly draw it into the working area between the rotor and stator. This causes high frequency pulses to interact vertically and horizontally. The turbulence intensifies the dispersion and produces optimum mixing of the suspension.
Maintain Your Laboratory Homogenizer
Three Words: Keep it Clean!
While the rotor and stator do the work, the rotor shaft contains a series of bearings and seals that can be damaged if not cleaned at the end of each homogenizing cycle. Moreover, cross-contamination can occur if you process different media without thoroughly cleaning the assembly.
Protect your investment and the integrity of your work by instituting a cleaning procedure. For suggestions please check our post on cleaning tips for CAT homogenizers.
For questions or to learn more about this equipment, call us or send a message.