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Index to Articles on Applied Chemistry.

INDEXERS.

THE EDITOR.

JAMES H. DE LONG, B. S.,

A. B. AUBERT

Lafayette College University of Maine

Copies of any paper marked with one or more asterisks will be supplied upon the following terms:

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Send orders to CHEMICAL ENGINEER INDEX EDITOR, NAZARETH, PA.

The publishers would like to call attention to several things in connection with this index. First of these is the fact that it is desired to be a complete catalogue of all the important articles upon analytical and applied chemistry appearing in the current issues of the more important scientific and trade journals of this country, England, France and Germany.

We are in position to secure for our subscribers at reasonable rates translations of any articles appearing in French or German journals. When a sufficient number of our readers notify us that such is their wish, however, we will have the desired article translated and published in THE CHEMICAL ENGINEER.

As to the best way of making use of the index we have this to suggest: The index is not only intended to keep our readers posted on what is appearing in the other journals, but also to serve as a permanent record of the literature of applied chemistry. To the latter end it is better that all the articles on one subject be grouped under that head rather than scattered throughout the several monthly indexes. This can be done in several ways. It will be noticed that the pages are backed by advertisements; they may, therefore, be cut out of the magazine without mutilating other contents, cut apart and each item pasted on a separate card. These cards can then be arranged between proper guide cards in a tray or a drawer cabinet. While this would require a little time each month to cut out the items and paste them on cards or in a scrap book, such an arrangement of all correlated matter under one head would save much time ultimately in looking over all the numbers for articles on a particular subject. This would also admit of a rearrangement of the items to suit the ideas and needs of each individual.

Below is a list of the journals regularly read and indexed for THE CHEMICAL ENGINEER each month. For the convenience of our readers, after each of the American journals are given its publishers, their address and the price of a single copy. In giving the reference to the volume, number and page of a journal, the volume is printed in Roman numerals, the number in bold face and the page in ordinary face Arabic numerals.

JOURNALS REGULARLY INDEXED.

American.

American Chemical Journal, Johns Hopkins Press, Baltimore, Md.
American Journal of Pharmacy, 145 N. Tenth St., Philadelphia, Pa.
Cement, Progress Pub. Co., 13-21 Park Row, New York.

Cement Age, 42 Broadway, New York.

The Chemical Engineer

Vol. VII.

March, 1908.

No. 3.

SULPHURETTED HYDROCARBON LOSS IN EVOLUTION METHODS FOR SULPHUR IN STEEL AND

CAST IRON.

By GEORGE AUCHY.

Chemist, Disston Saw Works.

It has been the universal belief among analytical chemists that in determining sulphur in pig iron by evolution methods, there is loss as sulphuretted hydrocarbon compound, but that this loss does not occur in the case of high carbon steels, and that in this latter case, therefore, evolution methods are accurate. In opposition to this generally held view, it has long been the writer's experience that there is also sulphuretted hydrocarbon loss in high carbon steels as well as in pig irons, and from a considerable number of experiments he was led to the use of a plus correction in his results of one-fourth in connection with the evolution method. These experiments were published in several different articles, but as far as he could see without making any impression whatever on other analyses. Several times since the publication of these results, the statement that there is no sulphuretted hydrocarbon loss in evolution methods applied to high carbon steels has reappeared, and it is evident that the popular belief to this effect has been entirely unshaken by the writer's evidence to the contrary. Nevertheless he could not himself doubt the accuracy of his work on this point, and when later he happened to see a statement which indicated that in Germany and Sweden the opposite view on this point to the view held in this country was the one generally accepted, his confidence in the correctness of his own observations (which agreed with the German idea) was increased and strengthened. The statement referred to appears in the journal of the Iron and Steel Institute for 1905, Vol. 2, page 417, in a paper by Dillner and Enström, entitled "Researches on the Magnetic and Electric Properties of Various Kinds of Sheet Steel and Steel Castings," and reads as follows: "For the determination of the sulphur, 10 grammes of the sample were dissolved in hydrochloric acid (Sp. gr. 1.12) in a flask with a cooling tube. The sulphuretted hydrogen evolved, which is generally mixed with sulphuretted hydrocarbons, was passed through a glass tube heated to redness. In this tube the sulphuretted hydrocarbons are decomposed into sulphuretted

hydrogen. The whole amount of the gas was then passed into a solution of acetate of cadmium whereby sulphide of cadmium was precipitated. The amount of this compound was estimated by titration with a solution of iodine. The method is known in Germany as the Schulte method."

This very plain evidence that in Germany, sulphuretted hydrocarbon loss had come to be a clearly and generally recognized part of the evolution method for steel brought to the writer the comfortable conviction that the Germans and himself were entitled to be credited with the possession of a certain amount of sagacity, and he manfully stuck to his one-fourth correction in opposition to the judgment of his employers, who were inclined to skepticism about it, and who in any case doubted the advisability of using it so long as nobody else did, or so long as nobody else on this side the water took any steps of any kind to prevent the loss. But this complacent consciousness of intrinsic worth on his part was afterwards destined to receive a rude shock. Some washed metal from the Youngstown Steel Co., was running higher in sulphur than their guarantee-0.020 per cent according to our analysis using the one-fourth correction which here the writer was especially sure of, because that there is sulphuretted hydrocarbon loss in pig irons is disputed by nobody, and is a matter of universal belief. So,

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when some samples returned to them were reported by them as being 0.018 sulphur the writer felt rather sorry for them, and did not think it worth while to check up his results by the aqua-regia method. But when a sample in which he had obtained 0.026 sulphur, using the one-fourth correction, was reported by Booth, Garrett & Blair, as containing 0.018 per cent sulphur by the aqua regia method the matter began to get serious, and the writer at last started an aqua-regia test himself, and on this same sample, but still with the utmost confidence in the outcome. For was it not an undisputed fact that in pig iron there was always sulphuretted hydrocarbon loss? But

to his horror and dismay his aqua-regia result came 0.019 per cent. Hastily he repeated some of his old work that had been published. The results came as before. The truth then began to dawn on him. The truth is that this sulphuretted hydrocarbon loss is not, as he had supposed, an inevitable occurrence either in pig iron or in high carbon steel. Nor on the other hand is it the case, as supposed by others, that the loss always occurs in pig irons, and never occurs in steels. Sometimes the loss occurs and sometimes it does not, depending on the condition the sulphur, or the sulphur and carbon, is in in the steel or in the pig iron, and there is absolutely no difference between steel and pig iron in this respect. This is shown in Table 1 which gives the results of tests afterwards made on these washed metals in dispute and also on some steels.

In washed metals the sulphuretted hydrocarbon loss occurred in one case and not in the other three. In the steels it occurred in five cases, and not in the other three. In the tests described and recorded in previous papers by the writer on this subject, the steels experimented with happened to be all of the same sort in respect to the condition the sulphur existed in, and this is why the writer made the mistake of concluding that the sulphuretted hydrocarbon loss always occurred in high carbon steels. The equally positive and mistaken belief of other chemists that it never occurs in high carbon steels is also doubtless due to the same happening, but in the contrary way. The question, of course, is, how may the error be avoided or overcome when it occurs? A Western Steel Works chemist, whose article is not at hand, and whose name cannot therefore be quoted, has found that annealing the drillings of cast iron with exclusion of air always brings the sulphur in such a condition that the hydrocarbon loss in evolution does not occur. Professor Phillips has used a hot porcelain tube to convert the evolved sulphuretted hydrocarbons from cast iron into sulphuretted hydrogen. This is also done in the Schulte method quoted in this paper. The writer made some hasty and unthorough tests of the annealing plan in steels, but the results though too hasty and incomplete to be conclusive were not encouraging, and he turned to the hot tube plan as the more promising; but attention has been diverted so far by pressure of other work.

An attempt is being made to create favorable public opinion with regard to the use of nickel-steel rails in place of the ordinary steel rails. Mr. Charles M. Schwab when he was with the United States Steel Corporation advised that plans be made to meet the needs which the railroads are now experiencing. He is of the opinion that the best rail material is a nickel, or some other alloy steel which will cost, roughly, about three times as much as Bessemer steel. The experiments made recently with nickel-steel rails. by certain railroads, however, have not been entirely satisfactory, but it is thought that eventually these costly rails will be considered to be the best by reason of the rapidly increasing traffic.

THE PURCHASE OF COAL UNDER SPECIFICATIONS.'

By J. E. WOOD WELL.
Continued from February issue.

As to the necessity for some such system, experience in applying a specification which penalizes a deficiency in heating value only, has developed an average deficiency of about 3.5 per cent, which on contracts aggregating $200,000 represents the sum of $7,000, of which not more than $1,000 can be charged for testing. Individual deliveries have in practice, as mentioned before, shown as high as 47 per cent of ash on a contract standard of about 6 per cent, and less than one-half of the stipulated heating value. Under the accompanying specifications coal of this sort would be subject to rejection, or, if used, would not command a payment adequate to reimburse the contractor for the cost of cartage alone. It is also doubtful if such coal is of sufficient value to the user to repay the cost of firing and the subsequent handling of ashes.

The system of sampling, analyzing, and testing coal delivered under the government contracts will be under the supervision of the Fuel-Testing Division of the Geological Survey, in order to insure reliability and impartiality.

The application of this system will not only enable the award of a contract to be made in an equitable manner, but will also remove many of the usual causes for dispute as to the character and quality of the coal subsequently delivered, and provide a satisfactory basis for the adjustment of payments for difference in quality in favor of the party in whose interest it is due.

It is believed that the enforcement of the provisions of the specifications will operate equitably both with respect to the government and to the contractor, inasmuch as a premium is provided as well as a penalty, and will guarantee adequate protection to each party. Many coal dealers have already signified their willingness to furnish coal on this basis, and have commended as well as indorsed the method.

This system of coal purchase has been established by the government for economic gain and it has been applied therefore with discrimination as to the size of the contract which will warrant such procedure. In general, it has been justified practically on contracts exceeding $2,000 in value, though other factors than price frequently influence the choice of methods of purchase, such as limited competition, availability of coal market, etc.

Experience in the use of this method shows that frequently the correction for moisture influences the heating values of coal, quite as much as variation in the ash content. In adjusting payments, therefore, on the basis

Presented at the annual meeting of the American Society for Testing Materials, held at Atlantic City, June 20, 21 and 22, 1907.

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