How to Dry a Molecular Sieve
- 1). Pour the used molecular sieves into a high surface area glass dish. Spread out the sieves in a thin layer to increase the open surface area.
- 2). Place the sieves in an oven that is heated to between 190 degrees C and 250 degrees C. Manufacturers specify different temperatures to dry their sieves. In general, the temperature specified lies somewhere between the two values given above. The oven used for drying the sieves should have a gas port for an inert gas to remove any water vapor released from the sieves. The gas used for this purpose is usually nitrogen. The nitrogen used for this purpose is dried to eliminate any water vapor being introduced to the oven.
- 3). Allow the sieves to bake in the oven for a minimum of two hours to ensure complete removal of water molecules.
- 4). Remove the glass dish with the sieves from the oven and immediately place it in a glass dessicator under a vacuum and allow the sieves to slowly cool in the absence of water. The dessicator is a sealed glass vessel that will keep items isolated from the air. The application of a vacuum to the dessicator further reduces the chance for water vapor contaminating the sieves and reducing their capacity.
- 5). Store the dried and cooled sieves in an air tight bottle in an inert atmosphere.
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