This ingenious design is used in the filtration and recrystallization of extremely air-sensitive materials on a high vacuum line. The filter tube has 14/20 standard taper inner joints at both ends and a 14/20 outer joint for connection to an AF-0540-10 or AF-0540-11 90° adapter (shown here, but sold separately; connects on the right side of the filter) which attaches to the vacuum line. The two halves of the filter frit are connected by a sidearm equipped with a 0-4mm Chem-Cap® valve, permitting one or both sides to be placed under vacuum.
In typical use, flasks are placed on both ends and a reaction is run in the bottom flask. Byproduct salts are then removed by rotating the frit 180° about the stationary adapter and the product is then crystallized in the second flask. The product is then collected by again rotating the filter frit 180°.
The filter frit component is available in 10, 20 or 30 mL sizes. The porosity of the sintered glass filter disc is medium.