定义Definition
索氏提取器是一种利用溶剂回流和虹吸原理，用少量溶剂对固体样品进行连续、反复萃取的玻璃仪器。它由烧瓶、提取管（带虹吸管）和冷凝管组成，常用于测定食品和饲料中的脂肪含量及提取天然产物。
The Soxhlet extractor is a glass apparatus that uses solvent reflux and a siphon to extract a solid sample continuously and repeatedly with a small amount of solvent. It consists of a flask, an extraction chamber with a siphon tube, and a condenser, and is used to determine fat in food and feed and to extract natural products.
工作原理How it works
样品装在滤纸套筒中置于提取管内。烧瓶中的溶剂加热汽化，蒸气经侧管上升到冷凝管，冷凝成纯溶剂滴入套筒浸泡样品；当提取管中液面升到虹吸管顶端时，含提取物的溶液通过虹吸作用全部流回烧瓶。如此循环往复，每次都用新蒸出的纯溶剂接触样品，提取物在烧瓶中不断积累，效率很高。
The sample sits in a paper thimble in the extraction chamber. Solvent boiling in the flask rises through a side arm to the condenser, condenses and drips as fresh solvent onto the sample; when the liquid in the chamber reaches the top of the siphon tube, the whole extract siphons back into the flask. The cycle repeats, each time bathing the sample in freshly distilled pure solvent, while extract accumulates in the flask, making extraction very efficient.
由来Origin
1879 年德国农业化学家弗朗茨·冯·索克斯雷特发明了这一装置，最初用于测定牛奶中的脂肪含量。索克斯雷特还发明了牛奶巴氏消毒的一种方法。
The German agricultural chemist Franz von Soxhlet invented the apparatus in 1879, originally to measure the fat content of milk; he also devised a method of pasteurising milk.
应用与改进Applications and improvements
用于测定粗脂肪（国家标准方法用无水乙醚或石油醚）、从植物中提取生物碱和油脂、从土壤中提取有机污染物以及从高分子中提取添加剂。缺点是耗时长（数小时至一天）、热敏性物质可能分解。加速溶剂萃取、微波辅助萃取和超临界流体萃取是现代替代方法。
It is used to determine crude fat (standard methods use anhydrous ether or petroleum ether), extract alkaloids and oils from plants, extract organic pollutants from soil and additives from polymers. Drawbacks are long run times (hours to a day) and possible decomposition of heat-sensitive compounds; accelerated solvent extraction, microwave-assisted extraction and supercritical-fluid extraction are modern alternatives.
年表Timeline
- 1879
索克斯雷特发明索氏提取器
Soxhlet invents his extractor