Ultrasonic topic: "Ultrasonically improved mass transfer"
Mass transfer is the net movement of mass from one location, usually meaning stream, phase, fraction or component, to another. Mass transfer occurs in many processes, such as solid-liquid and liquid-liquid extraction, catalysis, precipitation, dehydration and many other chemical and biological reactions. Naturally occurring mass transfer can be often very slow and time-consuming, so that mass transfer intensification by mechanical means is applied to accelerate reactions and processes. Efficiency of mass transfer is dependant on the effects on external or internal mass transfer resistance. External mass transfer improvement can be achieved by decreasing the boundary layer thickness. Internal mass transfer improvements are caused by sonication, where ultrasonic waves cause changing pressure fields and micro-mixing within the product.
Power ultrasound is an effective method to create shear forces, turbulences and micro-mixing in liquids and slurries. Acoustic cavitation is used to induce and accelerate chemical reactions due to improved mass transfer between reactants, to break cells and extract intracellular material improving the release of extracts by improving the mass transfer between cell interior and solvent, to improve diffusion coefficients and decrease the boundary layer of diffusion for dewatering and drying processes and many more applications.
Learn more about ultrasonic process intensification due to increased mass transfer!
Found 27 hits. Showing results 25 - 27.
Ultrasonically Assisted Saffron Extraction
Ultrasound is well known for its extraction capacity. The ultrasonically assisted extraction of active compounds, flavours and spices from plant material is a very successful application as ultrasonically generated cavitation disruptes plant cells and enhances mass transfer so that the…
https://www.hielscher.com/ultrasonically-assisted-saffron-extraction.htmSonocatalysis – Ultrasonically Assisted Catalysis
Ultrasonication affects the catalyst reactivity during catalysis by enhanced mass-transfer and energy input. In heterogeneous catalysis, where the catalyst is in a different phase to the reactants, ultrasonic dispersion increases the surface area available to the reactants. Background of Sonocatalysis…
https://www.hielscher.com/sonocatalysis_catalysis.htmUltrasonic Extraction and Preservation
Ultrasonic extraction and preservation utilizes using power ultrasound for the disintegration of cell structures (lysis). Breaking cells with ultrasonics results in highly efficient extraction of intra-cellular compounds as well as microbial inactivation. Due to numerous advantages, ultrasonication is widely used…
https://www.hielscher.com/extraction_01.htm

