I use 3a molecular seives in a filter dryer. Be carefull of the source of your seives, there is a lot of garbage out there from China and India that doesn’t meet spec. Heat the beads to 250c for an hour, place while still hot into vacuum oven or dessicator. Pull a hard vacuum and let cool to room temp. Then they can go into the filter dryer. To test the beads you can place a small amount of them into the bottom of a test tube. Insert a thermometer and add a enough water to just cover the beads. If the thermometer rises you know the bead is absorbing water. A hotter exothermic reaction indicates better bead quality. On a side note, if they are mixed with a substance with a molecular size larger 3 angstroms the beads won’t release heat. This indicates that the pore size is correct.