Ultrasonic disperser is a device that uses the principle of ultrasonic waves to disperse solid particles or liquid dispersions in liquids. It is widely used in fields such as chemistry, pharmaceuticals, environmental science, and materials research. The principle mainly relies on the physical effects of ultrasound, especially the cavitation effect, shear force effect, and acoustic vibration effect of ultrasound.
The principle of ultrasonic disperser
Ultrasonic cavitation effect
The propagation of ultrasound in liquid can cause rapid vibration of liquid molecules. When the intensity of ultrasound reaches a certain level, tiny bubbles will be generated in the liquid, which will continuously expand and eventually collapse under the action of ultrasound, forming a strong local high-temperature and high-pressure area. This process is called cavitation effect.
The high-speed liquid flow and local high temperature generated by cavitation effect can disperse solid particles into the liquid, reduce particle aggregation and agglomeration, and achieve dispersion effect.
The collapse of cavitation bubbles can also generate powerful shock waves, which can destroy the structure of large particulate matter, thereby achieving particle fragmentation and dispersion.
Ultrasonic shear force effect
When the vibration of ultrasonic waves is transmitted into a liquid, a very strong mechanical shear force is generated in the liquid. The high-frequency vibration of ultrasound causes liquid molecules to vibrate rapidly, generating significant shear forces that act between solid particles. These forces help overcome the attractive forces (such as van der Waals forces) and electrostatic forces between particles, breaking the phenomenon of particle aggregation and achieving uniform dispersion of solid particles.
High strength shear force not only helps to destroy solid particles, but also improves dispersion in liquids, preventing particle precipitation or aggregation.
Ultrasonic vibration effect
The high-frequency fluctuations generated by the vibration of ultrasound can accelerate the movement of molecules in liquids. The combination of vibration effect and cavitation effect helps to promote the interaction between solute and solvent. For dispersed particles, ultrasonic vibration can help particles better distribute in the liquid without easily aggregating.
Ultrasonic instruments often transfer ultrasonic energy to liquids through probes or sensors, and the bubbles, shear forces, and flow caused by vibration all work together in the dispersion process.
temperature effect
When ultrasonic waves work, the temperature of the liquid will rise, especially under the effect of cavitation, and the local temperature and pressure may be very high. This local high-temperature effect helps to dissolve or disperse certain substances, but attention should also be paid to avoiding damage to sensitive substances due to excessive temperature.
Summary of the working principle of ultrasonic disperser
Ultrasonic probe: The ultrasonic disperser converts electrical energy into mechanical vibration through the probe and transmits ultrasonic waves into the liquid. The vibration of the probe can cause the movement of liquid molecules and generate cavitation phenomena in the liquid.
Ultrasonic cavitation and shear force: The formation and collapse of cavitation bubbles generate strong local high temperature and pressure, driving the interaction between liquid and particles. At the same time, the action of shear force contributes to the fragmentation and uniform dispersion of particles.
Dispersion effect: Through these physical effects of ultrasound, solid particles can be quickly and uniformly dispersed in the liquid, avoiding particle aggregation or settling and ensuring high stability of the dispersed liquid.
Application field
Nanomaterial preparation: Ultrasonic disperser can effectively disperse nanoparticles in solution, avoid agglomeration, and obtain high-quality nanomaterial dispersion liquid.
Cosmetics and pharmaceutical industry: In the cosmetics and pharmaceutical industry, ultrasonic dispersers are commonly used to emulsify and disperse drug ingredients or active ingredients in cosmetics, improving product stability and bioavailability.
Environmental protection: can be used in water treatment processes to disperse pollutants in water or promote the degradation of harmful substances in water.
Food processing: In the food industry, ultrasonic dispersers can be used to disperse particles in food, such as spices, pigments, etc.
Advantages and Challenges
Advantages:
It can efficiently disperse particles, especially nanoparticles.
Non contact operation avoids direct contact with the sample.
Suitable for various liquids, including high viscosity liquids.
Challenge:
Thermal effects may occur on certain solvents or sensitive substances, leading to their degradation.
The cavitation effect requires high requirements for equipment and operating environment, and material durability and control of ultrasonic power need to be considered.
In summary, the ultrasonic disperser significantly improves the particle dispersion effect through the cavitation effect, shear force effect, and vibration effect of ultrasonic waves. It not only handles tiny particles in liquids, but also plays an important role in various research and industrial applications.