IA17DrSTRI;ILd S D ESGI.17EERISG C“E.VlISTRY’
April 15, 1930
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Improved Laboratory Condenser and Its Use in the Construction of Apparatus” Edward S. West
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SIXPLE and efficient lalmratory condenser of Pyres glass was recently described hy the writer (1). Tlir essential points of coiistructioii are: a iiarroJv space 1)etween jacket ant1 iiiiier tube. iiisuriiig a rapid flow of x a t e r : a thin iniicr tulle for rapid heat traiizfer; and the , I
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into the tube a distance equal to its radius or slightly furtlier, and are coiir-eniently arranged in two opposite rows, the indentations alternating. The indented condensers 1iaTe appriixiriiatelp the efficiency of a Liebig coil condenser of the saiiic length, and for ordinary distillations a coildenser with :til effective water coluinii of 8 to 10 inches (20 to 25 em.) is sufficient. These small condensers, both plain arid indented, have Iieeii foiiiid especially adaptable to the coiist,ructioii of pieces of allglass distillation apparatus of a variety of kinds. Figure 1 sliows an all-glass distilling apparatus, with trap, for thc. preparation of pure water. etc. An all-glass reflux-distilliiig apparatus is pictured in Figure 2 . In using this it is c o i i ~ r i i ieiit to connect hoth coiiclerisers in parallel with the water supply liy nieaiia of T-tulles. The water is permitted to flow through both coiidenserr (luring reflux and, for distillatioil, is simply cut out of the reflux condenser by a screw claiiip. Figme 3 represents ail all-glass steam-distillation apparatus with trap and Figure 4 a distilling flask with ground-glass thermometer holder and attached condenser. dimple aiitl coiiihiiiatioii reflux dibtilliiig heads may lie very easily ahaeinl:lecl.
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Figure 1-Distilling Apparatus with Trap
Figure 2-Reflux-Distilling Head with Condenser Attached
hole uelded into a compact. *turdy unit. Quite sati.factory wridensers caii be made by using a wniewhat heayier wall inner-tube and 4ipping the narrow n ater jacket on d h rubher tubing, although they are not quite so efficient a i the all-glass onesn ith ‘ thin 1% all tubes. The efficiency of the c o nd e n se r h a s b e e ii greatly increased by indenting the walls of the i n n e r t u b e . The ind e n t a t i o n s a r e best made by plugging one end of the tube, heating small areas, and applying a slight s u c t i o n . ’ 2 They s h o u l d e x t e n d
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1 Receixed February 17 1930 ’ C o n d e n s e r s a n d apparatus embodying them or t h e types discussed may be o b t a i n e d from Arthur H Thomas Co Philadelphia
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Figure 3-Steam-Distillation
Apparatus
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Figure 4-Distillation Flask with Stopper for Thermometer
The usefuliieas of such pieces of apparatus in the research lahoratory well repays the amateur glass ldower for the trouhlc of making them, and; since it is possible to obtain standardized prouiid-glass joints of Pyrex glass, their assembly is not difficult. Further adaptations of these condensers to the coiistruction of all-glass apparatus is evidently possible where it is not feasible to use the cumbersome and lees efficient Liehip type. Literature Cited (1, \vest, ISD.
E S G . CHEII.,
20, 737 (19281.
Correction I n the article by W. F. Faragher, J C hlorrell, and I. M Levine, entitled “Determination of Olefin and Aromatic Hydrocarbons,” ISD EXG CHEM, Anal E d , 2, 18 (1930), the column headings in Table XIV on page 23 should read “Benzine 1” and “Benzine 2,” instead of “benzene” as printed.
