抽滤Vacuum filtration

由布氏漏斗（或玻璃砂芯漏斗、赫希漏斗）、抽滤瓶（带侧管的厚壁锥形瓶）、橡胶垫圈、安全瓶和真空源组成。滤纸应略小于漏斗内径、能盖住所有小孔，先用少量溶剂润湿并抽紧。少量样品用赫希漏斗或小型砂芯漏斗。

The set-up comprises a Büchner (or sintered-glass or Hirsch) funnel, a thick-walled filter flask with a side arm, a rubber adapter, a safety trap and a vacuum source. The filter paper should be slightly smaller than the funnel's inner diameter yet cover all the holes, and is wetted with a little solvent and sucked down first. Small samples use a Hirsch funnel or small sintered funnel.

先抽气再倒入待滤液；用少量冷溶剂洗涤晶体时，应先断开真空，使溶剂充分浸润晶体再抽干；结束时先拔下橡胶管（或打开安全瓶活塞）通大气，再关泵，防止水泵倒吸。强酸、强碱或强氧化性溶液会腐蚀滤纸，应改用砂芯漏斗。抽滤瓶为厚壁玻璃，不能加热。

Apply the vacuum before pouring in the mixture; to wash crystals with cold solvent, release the vacuum first so the solvent soaks the crystals, then suck dry; at the end disconnect the tubing or open the trap to air before switching off, so water from an aspirator cannot suck back. Strong acids, bases and oxidants attack paper, so use sintered glass. Filter flasks are thick-walled and must not be heated.

1888 年德国化学家恩斯特·布赫纳发明了带多孔瓷板的布氏漏斗；水流抽气泵（文丘里原理）的应用使抽滤在 19 世纪末的实验室中普及。工业上的真空转鼓过滤机、板框压滤机是同一原理的放大。

In 1888 the German chemist Ernst Büchner invented the funnel with a perforated porcelain plate that bears his name, and the water aspirator (based on the Venturi principle) made suction filtration common in late-nineteenth-century laboratories. Industrial rotary vacuum drum filters and plate-and-frame filter presses apply the same principle at scale.