Vacuum Distillation

Vacuum distillation is the process of separating a mixture of liquids by evaporation and condensation. This is normally performed by heating the liquid until boiling occurs, indicating that the vapor pressure of the liquid has exceeded the ambient pressure.

However, heat can damage the structure of temperature-sensitive substances. In such cases, vacuum distillation is preferred, in which a vacuum pump is used to significantly reduce the boiling point of the liquid. A chemical duty diaphragm pump is recommended for this method.

Vacuum distillation is used across industries: 

• Pharmaceuticals: Purifying active ingredients without thermal degradation. 

• Petrochemicals: Separating heavy oils and residues. 

• Fine Chemicals: Isolating temperature-sensitive intermediates. 

• Food & Flavor: Concentrating extracts without altering taste profiles. 

Welch’s vacuum pumps are optimized for these tasks, offering corrosion resistance, low maintenance, and precise control. 

• Boiling Point Reduction: At 100 mbar, water boils at ~50°C instead of 100°C. 

• Pump Selection: Diaphragm pumps are ideal for solvents; hybrid pumps offer deeper vacuum for heavier compounds. 

• Material Compatibility: PTFE and corrosion-resistant alloys extend system life. 

• Flow Rate & Ultimate Pressure: Match pump specs to process requirements to avoid bottlenecks.