Counter-current Extraction
Counter-current Extraction - Related Videos
09:33
Determining Cell Number During Cell Culture using the Scepter Cell Counter
0 Views •
Cited by 57 •
2010
The Scepter Cell Counter is a handheld automated device that can be used to count cells, monitor cell diameter and volume, and be used to check the health and quality of cellular populations from one culture to the next.
09:21
Efficiency of Liquid-liquid Extraction
0 Views •
2023
Source: Kerry M. Dooley and Michael G. Benton, Department of Chemical Engineering, Louisiana State University, Baton Rouge, LA Liquid-liquid extraction (LLE) is a separation technique used instead of distillation when either: (a) the relative volatilities of the compounds to be separated are very similar; (b) one or more of the mixture components are temperature sensitive even near ambient conditions; (c) the distillation would require a very low pressure or a very high distillate/feed...
07:31
Agarose-Based Model Ecosystem for Cultivating Methanotrophs in a Methane-Oxygen Counter Gradient
0 Views •
2024
A protocol is described for preparing a simple model ecosystem that recreates the methane-oxygen counter gradient found in the natural habitat of aerobic methane-oxidizing bacteria, enabling the study of their physiology in a spatially resolved context. Modifications to common biochemical assays for use with the agarose-based model ecosystem are also described.
02:55
Extraction - Concepts
0 Views •
2020
Extraction Extraction is a common technique used in organic chemistry to isolate a target compound. In the extraction process, a solute is transferred from one phase to another to separate it from unreacted starting materials or impurities. Extraction is also used to facilitate the isolation of a solute from a reaction solvent that is difficult to remove by evaporation, such as a solvent with a high boiling point. Generally, there are three types of extractions. First, in solid-liquid...
13:16
Determination of Mammalian Cell Counts, Cell Size and Cell Health Using the Moxi Z Mini Automated Cell Counter
0 Views •
Cited by 18 •
2012
The Moxi Z miniature automated cell counter is a novel instrument that combines the Coulter Principle with patented thin-film sensor technology and a proprietary software algorithm to perform sizing and counting of a broad size range of particles as well as to determine the overall health of monodisperse mammalian cell cultures. This protocol describes the use of this instrument for counting and assessing the health of cell cultures.
FAQs
Opposing phase movement helps preserve a concentration gradient along the contact path. As the streams encounter one another repeatedly, the target solute can continue partitioning from its original phase into the receiving phase rather than quickly reaching a uniform concentration. This sustained driving force improves mass transfer and supports more effective separation in continuous engineering operations.
Immiscible phases remain sufficiently separate to allow a solute to move between them without the bulk streams becoming one phase. Their repeated contact creates opportunities for partitioning, while phase separation permits the enriched receiving stream and depleted original stream to be handled independently. This behavior is central to applying liquid-liquid extraction in engineered separation systems.
The opposite movement of the phases maintains contact between streams with different solute concentrations over the extraction path. That arrangement promotes continued transfer and makes better use of the receiving phase than a process that does not maintain the same concentration gradient. For engineers, the result is an effective basis for continuous separation and material recovery.
The defining process distinction is the direction of phase movement. Counter-current extraction sends the phases in opposite directions, allowing the concentration gradient to remain useful through repeated contact. That sustained gradient is associated with improved transfer and separation efficiency, making the arrangement especially relevant when engineers need scalable, continuous processing rather than a single contact step.
Engineers bring the two phases into repeated contact, allow the target solute to partition between them, and then direct the separated streams onward. The phases move continuously in opposite directions so transfer can occur along the equipment rather than only at one interface. The resulting streams can then be recovered as product, purified material, or treated output.
Extraction columns and mixer-settlers are identified as important equipment formats for implementing this process at scale. Both provide an engineering framework for contacting the phases and handling their subsequent separation, although the overview does not specify detailed design differences. Their inclusion reflects the method's suitability for continuous operations in chemical and other processing facilities.
Applications include recovering valuable compounds, purifying chemical products, removing contaminants, and concentrating materials. The technique is relevant across chemical, pharmaceutical, food, and hydrometallurgical operations, where engineers need to move a selected solute between phases. These uses connect the underlying mass-transfer mechanism with practical goals such as product recovery, purification, and process treatment.