Pervaporation Solvent Separation
Dehydrating solvents and separating mixtures
Dehydration of azeotropes is energy-intensive and also uses secondary entrainers. Pervaporation or vapour permeation easily, efficiently and economically dehydrates and breaks these azeotropes based on diffusivity and selectivity. This technology is getting accepted despite its higher capital cost. SOLVOSEP is used in chemical, petrochemical, Distillery, Aromatic and pharmaceutical industries for solvent recovery and reuse.
The solvent mixtures or compounds that are difficult to separate by other means can be separated using pervaporation membranes. Testing has to be done for unknown or typical combinations.
The system produces streams that contain varying levels of impurities. Separation is required to produce the quality that the customer demands.
Operation
Solvo-Sep pervaporation or vapour permeation consists of Hollow fiber, tubular or spiral wound, flat sheet membranes of Zeolite, and Polymers that separate in two modes. Liquid flow or Vapour flow.
A typical application is the dehydration of solvents, specifically ethanol and other solvents. The energy-saving and ease of operation, with no downtimes, promises it to be a chosen technology for the future.
There is a limitation of conventional distillation and breaking of difficult azeotropes. Solvo-Sep is an excellent add-on system to increase the profitability of distillation. Distillation is a traditional mixture of fluid separation technology that can separate components with different volatilities and markedly different boiling points (e.g. Benzene/toluene mixture). However, distillation is extremely complicated when the concentration of the separating components is similar in the liquid and vapour phases, called the azeotropic point (e.g. THF/water,
Acetonitrile/Water, Ethanol/water or IPA/water mixtures). Distillation alone cannot perform any further separation beyond the azeotropic point, which calls for the introduction of additional columns or entrainers.
Usually, the Solvo-Sep is a complementary technology to distillation. As a hybrid unit, it can dramatically improve the operation of a distillation column. Solvo-Sep breaks the azeotropes on a molecular level based on the selectivity of the membranes.
Features and Advantages
- Breaks azeotrope separation barrier.
- No introduction of additional chemicals for fluid separation.
- Maximises reaction kinetics, reactor efficiency and productivity.
- Complete reaction conversion, maximum product yield, and minimum reagent consumption cost.
- Efficiently dehydrates esters without decomposition.
- Robust membranes and Long life.
- Flexible process and simple unit design.
- Operates at modest capacities.
- Treat a large number of industrial solvents.
- Modular design. Simple, standardised, stand-alone or plug-in units, fully automatic operation if required.
Applications:
1) Solvents- azeotropes breaking and dehydration.
- Ethanol
- Propanols
- Butanols
- Acetates
- THF
- MTBE
- Acetonitrile
- IPA
- MEK
- MIBK
2) Removal of aroma components from aqueous streams.
3) Ethanol Recycling and reuse in perfume extraction.