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Reactive extrusion with twin screw technology |
Reactive extrusion
Since reactive extrusion emerged in the 1990s, it has developed more and more and today represents an important potential for the twin screw technology.
A twin screw extruder allows continuously controlling with the same equipment highly varied reactional environments, helping macro- and/or micro-mixing, effectively controlling a pressure and temperature profile, and forming the product.
Reactive extrusion is also developing around green chemistry, chemistry applied to agro-resources.
Learn more about reactive extrusion
Learn more about twin screw extrusion advantages
Reactive extrsion diagram
Clextral has acquired extensive engineering experience in reactive extrusion processes, notably several industrial achievements in the following fields : inorganic (alumina-based catalyst media), organic (devolatilisation and polycondensation of phenolic resins, saponification) or macro-molecular (functionalisation of polymers).
Thanks to their modularity, the Clextral twin screw extruders are especially well adapted to this type of application due, notably, to the process functions :
- Continuous chemical reaction
- Continuous mixing/blending
- Micro-mixing/macro-mixing
- Solid/liquid extraction
- Melting
- Degassing/devolatilisation
- Cooling
- Forming
What is reactive extrusion?
The term reactive extrusion applies when the extruder becomes the core of chemical reactions with a view to elaborate or modify products.
This technique is aimed at :
• The organic, inorganic, macromolecular fields
• Eligible reactions under High Temperature – Short Time conditions
• Systems limited by physical kinetics (viscous media, solid-liquid environments, etc.)
Reactive extrusion consists of producing a chemical reaction in the extruder under the combined effects of pressure, shear stress, and temperature.
What are the advantages of reactive extrusion?
This technology represents a strong substitution potential for conventional technologies implemented œin chemistry and offers the following advantages in terms of :
• Sober and intensified processes : the way in which the reagents are placed in contact reduces the quantities of reagents, catalysts and solvents used, and also reduces effluent volumes
• Control of the reaction kinetics and improvement of yields
• Production homogeneity : continuous production
• Confinement of the reaction, with the view of better protecting men and the environment, notably with respect to mixers or discontinuous reactors, which have the disadvantage of simultaneously implementing œlarge quantities of sensitive material, thus better preserving safety and the environment.
In addition, reactive extrusion allows responding to industrial situations confronted with the transition from a discontinuous process (batch process) to a continuous process.
Therefore, this technology allows developing new materials, while reducing the environmental impact since the reactions are carried out with more limited quantities of solvents, and thus effluent volumes are reduced.
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