July, 1911.] 



la 



OilslandlFats. 



are to be obtained. In reading through 

 the articles which have been published 

 on the geraniol test, we came among 

 others, upon a prescription* which 

 referred to the writer's " own method " 

 to the complete neglect of all the newer 

 investigations, especially those relating 

 to the acetylation of citronella oilt. At 

 the present time in particular this is 

 much to be regretted and show how 

 well-founded is our fear that the deter- 

 mination of geraniol will not always be 

 carried out accurately. We wish to 

 point out agaiu that in the case of 

 citronella oil in particular it is necessary 

 to adhere strictly to the prescribed 

 method, if the results are to be indica- 

 tive of the actual total-geraniol content 

 and are to be mutually comparable];, 



For this purpose we give below a 

 method by which we work in our own 

 laboratory, and which according to our 

 experience produces the best result with 

 mixtures of known geraniol and citro- 

 nella content. 



10 cc. each of citronella oil aud acetic 

 anhydride with 2 g. anhydrous sodium 

 acetate and a few fragments of porous 

 plate (in order to prevent the liquid from 

 bumping) are kept boiling at an equal 

 temperature in an acetylation flask for 

 2 hours on the sand bath. When the 

 mixture has cooled, a little water is add- 

 ed to the contents of the flask and the 

 whole is heated for a quarter of an hour 

 upon the water bath under frequent 

 snaking in order to decompose the 

 excess of acetic anhydride. The oil 

 is then separated in a separating 

 funnel and washed with water or, better 

 still, with a solution of common salt 

 until it gives a neutral reaction. Of the 

 acetylated oil dried with anhydrous sul- 

 phate of sodium, 1. 5 to 2 g. is saponified 

 with 20 cc of semiuormal potash-liquor, 

 any free acid which may have beeu 

 present having been previously care- 

 fully neutralised. The time of saponin 

 cation must be at least one hour. 



The reason, therefore, why we are not 

 so enthusiastic about the geraniol test 

 as those interested in the subject in 

 England, and why, for the present, 

 and so fat as regards the trade in Ceylon 

 itself, we continue to hold to a test for 

 Ceylon citronella oil which can be carried 

 out by anybody without special know- 

 ledge or trouble, is not to be sought in 

 opposition to the test itself, but rather 

 in the difficulties of carrying it out. 

 The method known as " Schimmel' test" 

 to which wa adhere may again be briefly 



* Chemist and Druggist 77 (1910), 896. 

 t Report April 1909, 36 ; April 1910, 154. 

 X Com p. Report April 1910, 154, 



repeated here in its original form. By 

 this test citronella oil must give a clear 

 solution with 1 to £ vols. 80° C, and this 

 solution must remain clear or may at 

 most show a slight opalescence upon the 

 addition of up to 10 vols. 80% alcohol. 

 Even after being left to stand for 

 several hours, no drops of oil may 

 separate out from the solution. As it 

 has been shown in the course of years 

 that oils which have been adulterated 

 to a moderate extent also stand this 

 test, we proposed some considerable 

 time ago* an "increased test" under 

 which an oil after being diluted with 5 

 per cent of Russian petroleum must also 

 answer the above test. We have been 

 able to convince ourselves both in our 

 laboratory here as well as by experi- 

 ments on the spot, that really pure 

 Ceylon citronella oils are able to stand 

 this '' increased test," and that con- 

 tradictory statements which have been 

 circulated from England are without 

 any foundation. Further experiments 

 have gone so far as to show that pure 

 Ceylon citronella oil will answer the 

 test even when instead of being diluted 

 with Russian petroleum it is diluted 

 with 5 per cent of the rather more 

 sparingly soluble American petroleum. 

 Where, therefore, Russian petroleum is 

 not available American may be used. In 

 that case, however, the opalescence is a 

 little more pronounced, but here, too, no 

 drops of oil may separate out from a 

 solution of 1 : 10, When the 10 vols, of 

 alcohol is being added the glass cylinder 

 should only be moderately tilted, be- 

 cause otherwise oil which may have 

 separated out is so finely suspended as 

 to make observation very difficult, 



If our proposals had long ago received 

 the attention which they merit, and if 

 Schimmel's "increased test" had been 

 generally introduced into commerce, the 

 present discussion would be wholly 

 superfluous, for in that case there would 

 no longer have been any complaint of 

 bad quality, seeing that ready solubility 

 also affords a certain guarantee for a 

 sufficient geraniol-content, To the ob- 

 jection that ways and means would 

 be found in Ceylon of so preparing 

 adulterated oils that they would pass 

 the "increased test," we may answer 

 that the same may be said with exactly 

 the same amount of justification of the 

 geraniol test. 



We may add that in the meantime we 

 have grudged no expense or trouble to 

 obtaiu really unadulterated citronella 

 oil from Ceylon, and we are glad to be 

 able to inform our clients that we are 

 now in possession of such an oil, which 



* Report April 1904, :W. 



