126
T H E JOURATALO F I N D U S T R I A L A N D ENGINEERIi\TG
dissolved; cool, place in 250 cc. flask, dilute t o mark a n d take aliquot portions for titration (see conditions under Pyrolusite). For all titrations of spiegels use N / I O (approx.) permanganate solution. The subjoined table gives results of analyses of the various products. Manganese found’ Percentage MnO
Sample Rock A2. . . . . . . . . . . . . . . . Rock 1 . . . . . . . . . . . . . . . . .
...
0.040 0.246 0.316
Rock4 . . . . . . . . . . . . . . . . . Rock 5 , . . . . . . . . . . . . . . .
0.278 0.346
Rock 6 . . . . . . . . . . . . . . . . Rock 7 . . . . . . . . . . . . . . . . Rock 8 . . . . . . . . . . . . . . . . Rock 9 . . . . . . . . . . . . . . . .
............ ............
Rock 12 . . . . . . . . . . . . . . . . Rock 13. . . . . . . . . . . . . . . . Iron slag 1 . . . .. ,
Mn
......... ....
0.04 0.163 0.283 0.183 0.283 0.223 Later Original colorigravimetric3 metric4 0.18 0.16 0.10 0.13 0.07 0.06 0.26 0.25 0.20 0.19 0.13 0.19 0.08 0.08 0.22 0.23 15.88
0.23 0.19 0.09 0.30 0.26 0.21 0.11 0.26 15.91 Percentage
Spiegel 1. . . . . . . . . . . . . . . . Spiegel 2 . . . . . . . . . . . . . . . .
Manganese found by other methods Percentage Mu0
Percentage M n gravimetric phosphate
11.09 21.01 30.55 80.10
11.10 20.99 30.49 80.22
57.09 57.07 57.11
B . of S. certificate High 56.63 LOW 56.15 Average 56.36
dri
..........
1 The results expressed here are the averages of two or more closely agreeing determinations. 2 This is a sample of Bureau of Standards argillaceous limestone, 28, 223. analysis by Hillebrand and Walters. See Jour. Am. Chem. SOC.. a These results were obtained by W. F. Hillebrand some years ago. Concerning them, Dr. Hillebrand writes: “The manganese was determined with the usual care bestowed on rock analyses, but not in duplicate.” And again, “ M y determinations on these particular rocks were made before I began t o determine the small amounts t h a t pass into the filtrates with the lime and magnesia. There was, too, always the possibility, in spite of a basic acetate separation, t h a t a little had not been separated from the F e and Al.” 4 “These tests were made with some care, by the color method, correcting for the i d u e n c e of color due t o the iron content of the rocks.”-W.
F.H. 6
Bureau of Standards analyzed “Sample No. 25.”
The method has been used successfully in this laboratory for some time. Whereas a little experience is required t o accurately determine the end point in titrating large amounts of manganese (40 t o 60 mg.), the end point is sharp and distinct a n d the results are very accurate in determining small amounts of manganese. The difficulties encountered in determining small amounts of manganese in rock and similar materials are known t o analysts and i t is believed t h a t the method here described overcomes these difficulties. It is also believed t h a t the principle involved in the above method may explain some of the discrepancies arising in the determination of ferrous iron in rock. CONTRIBUTION No. 2 14, HAVEMEYER LABORATORIES QUANTITATIVE LABORATORIES COLUMBIA UNIVERSITY
CHEMISTRY
Feb., I913
ANTISEPTIC TESTS O F W O O D PRESERVING OILS’ By A. L. DEAN AND
c. R.
DOWNS
The materials commonly employed for impregnating wood for the purpose of preventing its decay fall readily into two classes-soluble salts and hydrocarbon oils. The most widely used member of the first group is zinc chloride, and of the second, coal tar creosote. Ever since the introduction of this last named material by Bethel1 in 1838 i t has been employed in constantly increasing amounts, and today creosoting-properly performed-is regarded a s the most effective method of timber preservation. I n recent years the large demand for coal t a r creosote and the rather high cost of the treatment with the amounts considered necessary, have led to the use, openly and otherwise, of other materials. Thus the heavy asphaltic petroleum oils have been tried t o some extent, notably in the treatments by the Santa Fe railroad where sufficient of the oil has been injected t o render the wood well-nigh waterproof. The oil distilled from the t a r resulting from the manufacture of carburetted water gas has been used t o a considerable extent, but since its value was uncertain it has been regarded as a n adulterant or substitute for the oils distilled from coal tar. Water gas t a r shows many points of similarity t o coal tar, and the creosote oil distilled from it is very like t h a t distilled from coal tar, although it contains neither the phenols nor the nitrogenous bases characteristic of the latter. Inasmuch a s large quantities of water gas t a r are produced at the gas works in the United States, and the creosote distilled from i t might readily be had in substantial amounts, it is important t o arrive a t a sound estimate of its value a s a timber preservative. The qualities commonly desired in a wood preserving oil are freedom from loss by volatilization, solution or chemical change, and a marked toxicity t o wood-rotting fungi and the animals which destroy timber. I n volatility, solubility and chemical inertness water gas t a r creosote compares favorably with the oils from coal t a r ; the relative antiseptic powers of the two classes of oils are less readily determined. The present communication outlines the results of a laboratory study of the antiseptic powers of oils prepared from coal t a r and water gas tar, and is designed t o assist in arriving at a proper estimate of the place t h a t water gas t a r oils should occupy in timber preservation. The value of water gas t a r creosote as a wood preservative has been the subject of some controversy, but as yet the amount of reliable data has not been large. Practical tests on a commercial scale giving the results of the test of time under service conditions have not been carried out. Where the material h a s been used it has usually been employed in mixture with coal t a r creosote, sometimes without the consumer’s knowledge. The result has been t h a t in t h e absence of reliable information consumers have preferred to rely on coal t a r creosote of the value of which they were certain. 1 Paper presented a t t h e Eighth International Congress of Applied Chemistry, New York, September, 1912.
Alleman1 has studied the character of the oils remaining in timbers which, after being treated with coal tar oils, have been many years in service. The results show that the low-boiling oils present in creosote disappear after a number of years of service, and the t a r acids or phenols are no longer present. There has been in recent years a growing tendency to regard these high-boiling hydrocarbon oils such as Alleman found remaining in his well preserved timbers as the most valuable constituents of creosote oils. During 1911, J . M. Weissz presented two papers t o the New York Section of the Society of Chemical Industry, dealing with the antiseptic value of the oils and tars used in timber preservation. These papers showed the relative antiseptic value of coal t a r oils and water gas t a r oils under the conditions of Weiss’ experiments, as well as furnishing some information on the relative values of the different t a r oil constituents. These papers furnish the most important experimental evidence of the antiseptic powers of the different oils. The work of Weiss showed that coal t a r creosote was many times as toxic to the organisms used in his experiments as the water gas product, and that the lower boiling coal t a r oils were distinctly more antiseptic than the heavy high-boiling ones. Two criticisms may be made of the methods employed b y Weiss. The first, and less important, being that the fungi used by him t o test the antiseptic powers of the materials experimented on by him were not wood-destroying fungi and their powers of resistance t o various agents might not be the same. A much more serious objection t o his results depends upon the method employed in preparing the media containing the oils to be tested. These are for the most part insoluble in water and, being heavy, sink rapidly t o the bottom of the containing dishes, so that a uniform distribution of the oil is not effected, and the cells of the fungi may not come in contact with it. I t is apparent t h a t oils containing water-soluble constituents would partially dissolve and prove more antiseptic than the more insoluble oils. It might readily be that the relatively greater antiseptic power of the lighter coal tar oils was partly due t o solubility of the phenols present in them, the toxic power of which is well known. It would seem that a much fairer idea of the antiseptic power of the oils tested could be gained if they were uniformly distributed throughout the culture medium so t h a t the fungus must come in contact with them. The organism used in the experiments t o be described was Polystictus versicolor obtained in pure culture from wood decaying through the action of this fungus and bearing masses of its sporophores on the surface. Numerous cultures were kept in the laboratory on small blocks of sterilized Liriodendron wood on which i t grew readily, and which it reduced t o about the specific gravity and strength of pith in the course of a few months. There was no doubt of the purity of the cultures nor of the powerful attack of the fungus Gellert Allernan, Circular 98, Forest Service of the U. S. Department of Agriculture, May, 1907. J. M. Weiss, J. SOC.Chem. Ind., Feb. 28, 1911, p. 190, and Dec. 15, 1 9 1 1 . p. 1348.
on the wood. This species was used because of the readiness with which i t may be isolated in pure cultures which grow vigorously under laboratory conditions, and also because it is one of the most important enemies of structural timber in the United States. Von Schrenck’ says of this species: “Of all the fungi which grow upon the deciduous species of woods after they are cut from the tree, the most widely distributed and in many respects the most destructive is Polysticius versicolor. , . . . , On account of its wide geographical range and its ability to grow on and destroy so many different kinds of wood i t should be regarded as the most serious of all the wood-rotting fungi which attack the dead wood of broadleaf trees. I t is the fungus which destroys probably 7 5 per cent. or more of the broadleaf timber used for tie purposes.” Inoculations into the media to be tested could not be conveniently made from cultures growing on wood. and transfers were therefore made to prepared agar from which the fungus could be readily cut and small masses of the mycelium transferred by the use of a small piece of platinum foil set in a glass handle The culture media were prepared in the followring manner : Ordinary white beans (Phaseoltls vulgaris) were germinated in a dark place until several iaches high. The seedlings were then ground up in a meat chopper and a boiling water extract of them made. Due to the chemical changes characteristic of the process of germination some of the starch of the beans is hydrolyzed to dextrins and sugar, and much of the nitrogen present as the proteins of the seeds appears as soluble cleavage products in the seedlings. Onehalf of one per cent. of cane sugar and a like quantity of asparagin were added t o the germinated bean extract to supply further nourishment. This medium was then stiffened by the addition of 1.5 per cent. of agar agar, and I O cc. portions of it pipetted hot into 2 2 mm. testtubes, plugged with cottonandsterilized. A five-gram portion of each of the creosote oils to be tested was weighed out into a mortar containing a n equal weight of powdered gum arabic and the two rubbed well together. Water was then added a little a t a time with constant grinding, yielding a n emulsion containing a s the emulsifying agent a carbohydrate material similar t o the agar agar of the medium. The emulsion was diluted with water to I O O cc., making a 5 per cent. emulsion which would not separate even after several months of standing. Portions of these five per cent. emulsions were measured into the I O cc. portions of the sterilized agar medium with a pipette graduated to hundredths of a cubic centimeter. As a rule three test tubes of each strength were prepared in order to check the results. The agar was then melted and the tubes well shaken in order thoroughly t o mix the emulsion with the medium, and then quickly cooled under cold water in a slanting position. I n this way the oil was uniformly distributed throughout the medium in the form of finely divided globules and held permanently in position by the solidification of the agar. ‘ V o n Schrenck, Bull. 149, Bureau of Plant Industry of the U. S Department of Agriculture, p. 53.
T H E J O U R N A L OF I N D U S T R I A L A N D E N G I N E E R I N G CHEdFISTRY
128
I n the first series of tests the oils used were a very good grade of commercial coal t a r creosote, a water gas tar creosote made in the laboratory b y taking the fraction distilled from 170' t o 340' C. from a sample of water gas t a r of known prigin, and a sample of pressed anthracene oil. The results of the fractional distillation of the two first samples are given in the table below: TEMPERATURE DEGREES C.
.. . 170 205
240 300 320
170 205 240 300 320 340
COAL TAR CREOSOTE PER CENT.
0.2 6.3 30.7 21.3 9.1 13.5
WATER G A S TAR CREOSOTE PER CENT.
5.5 4.5 35.5 32.5 6.0
..
The coal t a r oil contained 8 per cent. of t a r acids. The anthracene oil was a commerical product, 50 per cent. of which distilled between 250° and 350' C. The solids had been pressed out, leaving it liquid at room temperatures. The strengths of coal tar creosote tested varied by 0.05 per cent. increments from 0.05 per cent. t o 0.35 per cent., a n d of the other two oils from 0.05 per cent. t o 0.75 per cent. The results of this preliminary series indicated a n inhibition point for the fungus with 0.25 per cent. of coal t a r creosote, 0.40-0.45 per cent. of the water gas t a r creosote, and over 0 . 7 5 per cent. for the pressed anthracene oil. I n the case of the last Famed material the growth became progressively weaker, b u t was not entirely inhibited a t the highest concentration tried. One serious difficulty developed in the tests. I n transferring the fungus mycelium t o the test tubes it was necessary t o cut out a small piece of the agar of the stock culture and it was almost impossible t o tell whether the fungus was growing slightly on the creosoted agar or whether all the growth was derived from the small piece of transferred medium. This led to some uncertainty a s t o the precise point a t which growth was inhibited. I n the second series, this was remedied b y cutting out a small piece of the medium t o be inoculated with a sterile platinum foil, laying the cut out piece over t o one side, placing the transferred mycelium and agar from the stock culture in the cavity, and then replacing the piece of creosoted medium on top of the transferred material. I n this way the mycelium used for inoculation was buried within the mass of material t o be tested and if it grew up through it and vegetated at the surface there could be no question t h a t the antiseptic was insufficient t o prevent the growth of the fungus. The control cultures were made in the same manner. The too rapid drying out of the cultures noticed in the first series was prevented in the second b y placing them in a large glass walled case with a water-saturated atmosphere. Since the fungus used in the first series might have had its vitality somewhat impaired b y being kept so long in artificial cultures, new samples of wood decaying through the action of the organism were found and fresh, pure cultures prepared and used for inocu-
lating the second series of oils were tested:
Feb., 1913
tests.
The following
A. Coal tar creosote No. 1. B. Coal tar creosote No. 2, prepared in the laboratory by taking the fraction distilling from 200' t o 350' C . , from a sample of coal tar; since there was a considerable separation of naphthalene in this sample on cooling to room temperature, which rendered it impossible t o make a satisfactory emulsion, the solids were filtered off. C. Water gas tar creosote No. 1 . D. Water gas tar creosote No. 2, prepared in the laboratory by taking the fraction distilling from water gas tar between 200° and 350° C.,yielding a sample somewhat heavier than the No. 1 and comparable in boiIing range with coal tar creosote No. 2. E. The same sample of pressed anthracene oil used in the first series. F. Coal tar cre060te No. 1 , washed with alkali until free from tar acids and then washed with water. G. A portion of F. with the tar bases removed by treatment with sulfuric acid, and washed with water.
An attempt was made t o make emulsions with anthracene and naphthalene for antiseptic tests in the manner described above for the oils, but i t was found impossible t o make satisfactory emulsions. The attempted stock emulsions of these materials containing about 5 per cent. of the hydrocarbons stood for some time in the laboratory and it was noted t h a t a mold growth appeared on the surface. The naphthalene and anthracene had settled t o the bottom. This observation would tend t o support the statement made by Weiss t h a t these materials were not antiseptic up t o I O per cent. This conclusion seems not t o be wholly justified, however, because the mold was not in contact with the hydrocarbons. The results of the tests in the second series were as fOllO\\~S: INHIBITION POINT PER CENT.
SAMPLE
.. . .
. ... .. . . ... .. ..
. . . . . . . Below 0 . 1 A. Coal tar creosote No. 1 . . . . . . . . . . 0.1 B . Coal tar creosote No. 2 . . . . . . . , . . . . .. .. 0.4 C. Water gas tar creosote No. 1 . . 0.35 D. Water gas tar creosote No. 2. E. Pressed anthracene o i l . . . . . . , . . . . . . , Above 0 . 8 5 F. Sample A. minus the phenols.. . . . . . . . . . . , . . . . . 0.30 G. Sample A. minus the phenols and tar bases
. .
.
. . . . . . ... . . .
In the case of sample E there was a gradual weakening of the growth from 0 . 2 per cent. t o 0.85 per cent. which was the highest concentration tried, and a similar state of affairs developed in the tests of sample G, the highest strength of which was 0.6 per cent. Of the two, cultures with sample E were slightly the more vigorous. From these results i t is evident t h a t coal t a r creosote is a stronger antiseptic t h a n water gas t a r creosote, and t h a t water gas t a r creosote is distinctly more effective than the liquid oils of the anthracene fraction of coal tar. The greater value of the coal t a r oil appears t o depend upon the presence of the t a r acids and especially upon the t a r bases. It is interesting to note t h a t the water gas t a r creosote was almost identical in antiseptic power with the coal tar oil with its t a r acids removed. The work of Alleman cited indicated t h a t the oils remaining in wood treated with coal t a r creosote are almost free from t a r acids after a few years of service, and t h a t under conditions allowing evaporation the lighter hydrocarbons are nearly all lost. Loss of antiseptic power from the disappearance of the t a r acids cannot take place with water gas t a r oils, since they are free from phenols in the beginning.
Feb., 1 9 1 3
T H E JOZ-R-\rAL OF I - V D C S T R I A L
Since the amount of creosote injected into wood I O pounds per cubic foot or more, it would appear t h a t the difference in antiseptic value between coal t a r oils and water gas t a r oils is not of great significance, especially in view of the probable disappearance of the t a r acids from the wood treated with coal t a r creosote. On the basis of such data as we have it seems justifiable t o conclude t h a t the oils distilled from water gas t a r have a distinct value a s wood preservatives, and t h a t there is no reason why they should not be purchased and used under their own names with no attempt t o masquerade a s coal t a r products.
is commonly
,
SHEFFIELD SCIENTIFICSCHOOL, YALE UNIVERSITY NEW HAVEN,CONN.
THE OXYGEN ABSORPTION TEST FOR LINSEED OIL’ B y HANS MANNHARDT
This subject has received considerable prominence in this country through a report b y a sub-committee on paint oils submitted a t the Atlantic City meeting of the American Society of Testing Materials last July. The report covers twelve pages, and t o any one taking the time t o compare the results of the four experimenters, i t must be a t once apparent t h a t either the method is not a quantitatively reliable one, or t h a t some essential requirement has been overlooked ; their results are t o be found in the “191 I Proceedings.” I will quote a few classic and correct results from the standard work on drying oils b y And&, English translation published by Scott, Greenwood & Co., in 1901,where extensive citation is made of Weger’s and Lippert’s results in the changes in weight which thin films of various oils undergo when exposed t o the air on glass plates. Weger’s glass surfaces were about 15 square inches in area and on these surfaces he applied weights of oil varying, if possible, only between 2 5 and 50 milligrams. His results in a condensed form follow: Time of dry- Per cent. ing t o maxmaximum imum change change in in weight weight Linseed oil, Artists’ Linseed oil, Artists’, Linseed oil, English, bottled 5 years..
...
....
Heated t o 150’ C.. . . . . . . . . . Cold blown Linseed oil, East Indian seed: Cold blown, 25 hours ..... H o t blown, 25 hours Linseed stand oil.. .................... Litharge boiled linseed oil., .... Linseed oil and 2 per cent. lead m resinate (no heat used). Rosin oil without driers.. . . . . . . . . . Rosin oil (6 .% per cent. lead and manganese resinate added a t 120’ C.) Wood oils,raw, punty not vo Hemp seed oil, raw.. . . . . . . . .... POPPYseed oil, ram.. . . . . . . ....
................
}
.....
Looking over the tables in the
3 . 5 days
17.0 15.5 19.7
6 6 8
days days days
17.3 17.0 16.7
5 . 5 days
8.2
18 16
days hours
17.5 loss 26.5
6.5 days
gain 25.7
3to8days 4 days 6 . 5 days “
129
several experimenters used weights of oil varying between the following limits: Grams A....................... B........................ C. . . . . . . . . . . . . . . . . . . . . . . . D........................
0.0774to0.4011 0,2877 t00.9498 0.2934to 0.8812 0.1711to 2.7318
On the basis of Weger’s results they should have used 0.062 t o 0.150 gram. Small wonder t h a t their results were erratic! You will notice t h a t Weger was successful in drying a film of rosin oil. On page 187 of the “ I ~ I Proceedings” we find statements of three of the experimenters t h a t their films of rosin oil and drier would not set hard. Furthermore, only two of the experimenters found any gaining in weight. The fourth experimenter did not report. Now,W. Pritchard,’ mentions a n X L rosin oil with “rather remarkable drying properties.” I also find that thin films of “first rztn” rosin oil can be caused to set into a nontacky film by the use of a proper amount of drier, while “second run,” “third r u n ” and “fourth r u n ” oils did not appear suitable.
Number
of
Days 0ry;np
FlG. A
Apparently each redistillation decreases the suitability of the product so t h a t “first r u n ” is a t once the cheapest and the most suitable for use in paint vehicles. T h a t is about all C\he discussion required b y those twelve pages of results in the I ‘ 1911 Proceedings.” Let us now see what recent literature has t o say about the value of the determination of the gain in weight of a film of linseed oil; and in this connection I have selected data bringing out fully the relationship between oxidation by oxygen and by halogen. Farbcn-Zeitung, October I , 1910,page 1 7 , states as follows: “ T h e Hub1 iodine values usually vary between 170 and zoo for raw linseed oils, however:-
11.1 14.6
8 . 5 hours 48 days
AND EXGINEERISG CHEMISTRY
+14to+17 13.6 13.4
1911 Proceedings,”
I find t h a t the glass area t o be covered with a film of drying oil was approximately 35 square inches.
The
Read before t h e Chicago Section of the American Chemical Society, March, 1912. Revised by the author.
Calcutta.. . . . . . . 0.931 3 . 1 194.5 L a Plata. . . . . . . . 0.932 2 . 7 193.2 L a Plata . . . . . . . . 0.932 2 . 9 190.4 1 J . S. C. I.. May 15. ?912, p. 420.
1.5 1.7 1.2
25.2 24.1 22.3
80 85 83
18.0 19.1 18.4
164.5 161.1 160.2
I
