OCl ^ i 1 

 GIFT 



Issued September 22, 1911. 



United States Department of Agriculture, 



BUREAU OF CHEMISTRY Circular No. 80. 

 H. W. WILEY, Chief of Bureau. 



TWO NEW PIECES OF CHEMICAL APPARATUS. 



I. Apparatus for the continuous extraction of liquids with immiscible solvents lighter 



than -water. 



II. Apparatus for quantitative reactions which depend on the measurement of an 

 evolved gas. 



R. F. BACON and P. B. DUNBAK, 

 Assistant chemists, Division of Foods. 



I. CONTINUOUS LIQUID EXTRACTOR. 



This apparatus was designed originally for use in the extraction of 

 lactic acid from ketchup and other fruit products. Its principal 

 advantages are compactness, the elimination of ground joints and 

 stoppers, and practically complete condensation. Seven of the ex- 

 tractors may easily be placed side by side on a 24-inch hot plate. 

 They have been made for the authors at a cost of $1.50 each, but may 

 be constructed in the laboratory by anyone having ordinary skill in 

 glass blowing. 



The apparatus consists of four parts: (1) A jacket flask; (2) an 

 extractor thimble; (3) an ordinary Gooch funnel; (4) a condenser. 



(1) The jacket flask (fig. 1, A) -is made of glass tubing 2 inches 

 in diameter and approximately one-sixteenth of an inch thick; it 

 is 20.5 inches long and is enlarged to a diameter of about 3 inches 

 at its lower or sealed end, as shown in the illustration. (2) The ex- 

 traction thimble (fig. 1, B) is an ordinary test tube having a diam- 

 eter of 1.5 inches and a capacity of 100 cc when filled to within 1.5 

 inches of the top. One-fourth of an inch from its top and on op- 

 posite sides of the tube are placed two holes about one- fourth inch 

 in diameter. (3) The Gooch crucible funnel is figure 1, C; those 

 used in this laboratory are 8.5 inches long. When dense liquids are to 

 be extracted it is sometimes necessary to increase the length of the 

 funnel. The lower end of the stem is ground at an angle of 45 

 degrees. (4) The condenser (fig. 1, D) is designed to hang loosely 

 in the jacket flask. Its details are evident from the drawing. A 

 simpler form of condenser, which is just as efficient, may be made by 



5873 Cir. 8011 



