AVA LYTICAL EDITION
418
SAMPLE
Table I-Calibration of Micro-Viscometer DELIVERY TIME CONVERSION Saybolt
Micro
Seconds
Szconds
44 5 92.8 112.9 191 5 3x3 484 717 ion1
FACTOR
de\-ice used for removing excess oil from the overflow gallery or by any other convenient means.
6 84 7.14 7.24 7.2X 7.44 7.52 7.47 7.57
6.5 13.0 1.5 6
26 3 51.4 64.n 96 0 132.0
Vol. 2, No. 4
Obtained w i t h a 28.6-cc. Receiving Flask DELIVERY TIME RATIO 60 cc. 28.6 cc. 60 cc./28.6 CC. Seconds Seconds 2354 788 2.98
Table 11-Results SAMPLE
1
1846 1139
2 3 4
864 784 519 383
5
Testing of High-Viscosity Oils
6 7
The Engler visccmeter, which is of German origin, is frequently used to determine the efflux time of 50 cc. of oil instead of the normal 200 cc. (3, h ) , thereby effecting 5 substantial saving in the time required to test oils of high viscosity. It has seemed desirable to adapt this principle to the Saybolt viscometer, and theoretical calculations, checked u p by experiments. have shown that the time required for the outflow of 28.6 cc. of any given oil is one-third that required for the outflow of 60 cc. of the same oil. Figure 2 shon-s the shape and approximate dimensions of the flasks which have been used. Table I1 shows results obtained with a typical flask in the writer's laboratory. Each figure listed is an average of the results of two or more individual tests. The operating procedure is the same as that involved vhen a 60-cc. flask is used. The oil remaining in the tube after discharging 28.6 cc. can be withdrawn by means of the vacuum
917 379 337 289 262 173 128
ioio
8
2.99 3.00 3.00 2.99 3.00 3.00 2.99
The saving of time is obviously advantageous and there is a negligible sacrifice of accuracy. It is believed that this device might well be standardized by the A. S. T. AI. for the testing of lubricating oils having high Saybolt viscosities. Acknowledgment The writer wishes to thank E. M7, Dean, director of tlie Standard Inspection Laboratories, for his criticisms, suggestions, and the interest he showed in this Jvork. Literature Cited :1) Adkin5 and Roger, I K D . EsG. CEEM.,20, 742 (1928). ( 2 ) A S.T. 1 1 . Standdrds 11, I f e t h o d D 88-26, p . 427 (1027). 13) Bleyberg, Pelroleurn, Z.,24, 1416 (19288). (4) Upton, Cornell University Ens. Expt. Sta., Bull. 5 ( 1 9 3 8 ) .
A General Utility Laboratory Still' Gilbert Pitman FRUITPRODUCTS
LABORATORY, UXIVEKSITY
URING the past few years there has been occzsion ' to recover considerable quantities of alcohol, acetone, and petroleum ether in this laboratory. Gradually the still herein described has been assembled until it is now nearly foolproof and continuous operating. The necessary equipment may be found in any laboratory and no special technic is required for its assembly. h 2liter Pyrex short-neck flask is fitted with a 3-holed rubber stopper. Through this are fitted a drain tube from the bottom of the flask to remove residual liquids, a fractionating column, and a tube from the reservoir. By closing the two stopcocks it is possible to obtain a vacuum-tight apparatus for vacuum distillation. A 500-cc. separatory funnel makes a very convenient reservoir. By filling the flask through the reservoir it is not necessnry to remove a single stopper, a feature that will be found convenient during vacuum distillation. This still may be run continuously except for the few moments necessary to remove the residual liquids through the drain tube by suction. Perhaps the feature of greatest convenience is the leveling bottle that prevents the water bath from boiling dry. The outlet tube is set at the level desired in the water bath, and any water lost due to boiling is replaced by the siphon from the leveling bottle. The water in the leveling bottle is supplied froin the drain of the condenser. The flow of water through the system should be so regulated that the outlet tube will be drawing some air from the open end to prevent building u p a back pressure.
D
1
Received June 10, 1930.
OF C h L I f O R S I h ,
BERKELEY,
CALIF.
Once installed, this apparatus will soon pay for itself in time and trouble saved.
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