Vacuum ovens are commonly used by extract manufacturers, specifically BHO makers, to purge butane and other impurities from concentrates. This specialized oven dries cannabis through a vacuum chamber rather than through conductive or convective heat. A vacuum chamber reduces pressure and boiling points of substances inside the oven, allowing for easy evaporation of unwanted contaminants. 

“A vacuum oven is necessary to properly purge BHO if you want to pass strict testing standards in the legal cannabis market.” 

How does a vacuum oven work?

Vacuum ovens have commonly been used in the electronics, aerospace, and medical industries for years, but have recently seen an increase of use in the cannabis industry. A vacuum oven is unlike traditional ovens that heat by conductive or convective heat, instead, the chamber is vacuum-sealed and the vacuum itself heats and dehydrates cannabis inside the vacuum oven. 

The vacuum lowers pressure and boiling points for most substances which allows for the evaporation of unwanted contaminants or residual solvents, like butane in a BHO extract. Using a vacuum oven will result in purer and more compliant products that are safer and more likely to pass the required residual solvent testing. 

Vacuum ovens are also safer for operators by controlling butane fumes which are combustible. Vacuum ovens are expensive pieces of equipment and an investment that extract makers should put time and research into, as there are many options out there and no two vacuum ovens are the same.