Isopropyl Alcohol Dehydration
Isopropyl alcohol (C3H8O or CH3CHOHCH3 or (CH3)2CHOH) dissolves a wide range of non-polar compounds. In addition, it evaporates quickly, leaving nearly zero oil traces compared to ethanol. Also, compared to alternative solvents, it is relatively non-toxic. Thus, it is widely used as a solvent and as a cleaning fluid, especially for dissolving oils.
Isopropyl alcohol is miscible in water and forms an azeotrope. The azeotrope formed exists at a composition that is 91% by volume isopropyl alcohol and 9% water. Hence to achieve dryness levels below this, simple distillation cannot be used.
However, isopropyl alcohol dehydration via molecular sieve has proven an effective means of drying IPA beyond the azeotrope.
Molecular sieves rely on the difference in molecular size between the solvent and water to achieve separation. IPA has a molecular size of ~16A and water has a molecular size of 2.6A allowing a 3A or 4A molecular sieve to adsorb water and allow the IPA to pass through the bed. The molecular sieve beads then undergo a regeneration step whereby the adsorbed water is removed. This enables the sieves to remove more water when wet alcohol passes through during the next dehydration cycle.
Wintek designs and builds Isopropyl Alcohol Dehydration (IPA) MSDUs (both Liquid Phase and Gas Phase) depending upon the incoming water concentration and outgoing dryness requirements.