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alloy steels, and the chemist has been called upon t o devise ways and means for their development and study. This evolution has indeed presented many a knotty problem t o the analyst as well as to the chemist in the works. It is no easy chemical task to separate, estimate and control such elements as tungsten, chromium, vanadium, titanium, nickel, cobalt, molybdenum and tantalum as every-day constituents of steel. Space will permit of only the briefest reference to the very important place that the curious alloys have made for themselves in t h e metallurgy of iron and steel. The tungsten, chromium, cobalt and molybdenum alloys of varied composition constitute the modern “high speed” steels which have revolutionized machine shop practice, Vanadium and chromium are used in the manufacture of the so-called anti-fatigue steels for springs and other rapidly moving machine parts. At the Xew York meeting of the Eighth International Congress of Applied Chemistry, in 1912,Dr. Carl Duisberg referred t o the use of some of these new alloys as follows: “Of great importance are those alloys of iron with chromium, tungsten and vanadium which possess a high degree of hardness even a t 4oo-500° C. They are needed by engineers for the construction of steam turbines, for the embossing and spraying of metal objects when heated t o redness, a process which has lately found extensive application. Chemists use these kinds of steel wher-ever chemical reactions are carried out a t high temperatures and pressure, as in the synthesis of ammonia according to Haber’s process.” According t o Dr. Duisberg, the very latest alloy manufactured by Krupp for the manufacture of safety vaults and safes can neither be drilled nor exploded nor can it be cut by the oxyhydrogen flame. I n the light of subsequent events we are led to presume t h a t the manufacture of safes was not the only purpose in the minds of our chemist-colleagues across the watex. It is interesting to note in passing t h a t unless the chemists of Germany had worked out the synthesis of nitrogen compounds from atmospheric nitrogen as well as the special steels suitable for the construction of the necessary apparatus, the present great world war would have t o he brought t o an early close. Another important contribution of chemistry to the iron industry which may be called purely American is along the line of the manufacture of pure iron on the same scale which is usual in steel production. This development, which the writer is in large measure responsible for, has had t o win its may against many difficulties and even much prejudice and hostility. Many hundred thousand tons of commercially pure iron are now produced annually in this country and. are in demand for many purposes for which iron is more suitable than steel. Pure iron is soft and ductile with a high electrical conductivity and useful magnetic properties; for many deep drawing and enamelling purposes it is unequalled, while its slow rusting qualities have given it a wide-spread reputation and use. Some years ago the demand for pure iron could be filled only by the importation of Norway and Swedish charcoal irons; a t the present time the industry is fully established in this country on the large scale which our industrial and economic conditions demand. That the chemist has contributed to this line of development there can not be the slightest doubt. It has been found necessary t o eliminate the gaseous as well as the solid impurities from these pure irons, and this difficult problem has engaged the closest cooperation between the men in the laboratory and the mill. I n a brief review of this nature i t is possible to touch only lightly on the many contributions of chemistry to the iron and steel industry, but the writer’s experience is that unless the divisional superintendents in a modern iron and steel plant are themselves chemists as well as metallurgists, they can not be depended upon to carry on progressive work. INSTITUTE O F INDUSTRIAL RESEARCH WASHINGTON, D . C.
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CONTRIBUTIONS OF THE CHEMIST TO THE ART OF SOAPMAKING By MARTINHILLITTKER Chief Chemist, Colgate & Company, h-ew Jersey
Although the art of soapmaking is of long standing it has undergone considerable improvement during recent years. The advance in the science of chemistry has contributed in no small way to the number and magnitude of the successes in this field. Soapmaking is connected almost inseparably with a number of other related industries among which the chief are the manufacture of alkali, glycerine, edible fats and oils, and perfumery, while the manufactures of candles and lubricants are industries closely associated with soapmaking. Blthough many of the larger soap manufacturers make their own caustic soda from soda ash, the manufacture of alkali is a great industry in itself. I would be neglectful, however, if I failed to state here t h a t the manufacture of alkali has advanced so that most of the alkali now on the market is of very high quality and is sold a t a very reasonable price. It was only a comparatively few years ago that the greater portion of the glycerine formed during the process of soapmaking was wasted. It was thrown away with the spent lyes in the process of making “curd” soap, or was left in the soap in the so-called “cold made” soap. An increased demand for pure glycerine for the manufacture of explosives, confections, and pharmaceuticals has stimulated the soapmaker to recover his glycerine and an article that was once a neglected by-product has now assumed so much importance that no soapmaker could operate with any degree of success without recovering his glycerine, and the profit from the recovery of glycerine is frequently greater than that from the manufacture of soap itself. A knowledge of the physical and chemical properties of glycerine has been utilized in the various processes which have been devised to recover and purify this valuable body. The most important part of these processes is the distillation of the glycerine by means of steam ilz vacuo. It is not necessary to operate a t a temperature sufficiently high t o cause any decomposition of glycerine, as was the case in older methods, and improvements in processts employed have worked economics in yield and cost of production. Glycerine of the highest degree of purity is now regularly made on an enormous scale from soap lyes. During the operation of soapmaking the glycerine is gradually removed from the soap by successive washes. Chemical analysis enables the soapmaker to estimate the total amount of glycerine possibly obtainable in a given operation. Chemical control and a consideration of the cost of operation taken together with the value of glycerine enable him t o ascertain the most economical conditions of working. The process of making “settled” soap, carried on under chemical control, enables the soapmaker to readily produce soap of uniformly high quality. b’ith an aim to the simplification of the process of soapmaking and the realization of greater economy, new methods of hydrolyzing fats and oils have been devised. In some of these methods, notably those in which sulfo-fatty acids are used, the hydrolysis is effected a t atmospheric pressure. Hydrolysis by means of enzymes is also used to some extent By these processes the larger part of the glycerine is readily recovered and fatty acids suitable for soapmaking are produced. When materials of poor quality are used, as, for instance, cottonseed soapstock, the fat may be hydrolyzed into fatty acids and glycerine, the glycerine recovered, and the dark acids subjected to distillation with steam in vacuo, whereby white fatty acids, suitable for making good quality soap, may be obtained. A new method of lime saponification gives a lime soap that is brittle and readily pulverizable and which is insoluble even in boiling water. By this method, which requires somewhat
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more mechanical handling than other methods, all of the glycerine may be recovered and the lime soap may be converted into soda soap by means of soda ash, giving a soap of good quality. The soapmaker is not blessed with a market in which he can obtain a t will a steady supply of fats and oils of uniform quality a t uniformly reasonable prices. His supplies must be drawn from all over the world and consist of animal and vegetable fats and oils. They include tallow, lard, cotton oil, peanut oil, soya-bean oil, olive oil, cocoanut oil, palm oil, marine animal oils, etc. His principal competitor in the markets of the world is the manufacturer of fat and oil food products. In some cases the soapmaker is also a manufacturer of edible products and a t times converts a large part of the fats and oils which he handles into first-class food products, and sells them as such. It has thus become necessary for the soapmaker to develop methods of refining and purification whether the product is to be used as food or t o be made into soap. A knowledge of the physical and chemical properties of various fats and oils used in soapmaking makes it possible to get a uniform and satisfactory result by the proper employment of different combinations, thus enabling the soapmaker t o utilize the cheaper materials available a t any given time. If he could not accomplish this result he would be a more serious competitor to the manufacturer of edible fats, with the result that both our edible fats and oils, and soaps would cost more to the consuming public. The process of hydrogenating soft oils whereby hard fats may be obtained, has been worked out by a number of soapmakers. Although hydrogenated oils have been and are used on a comparatively large scale in soapmaking, their principal employment up t o the present time has been in the manufacture of edible fats. The soapmakers are the largest consumers of perfume materials in the world. Most of the soaps on the market, even the cheaper grades, are perfumed. There is a popular misconception that perfume material is used to cover up inferior materials. If this was ever the case it can scarcely be so considered now. Perfumes are added to soaps for two reasons: to make them more attractive to the consumer, and because of the fact, well known to all soapmakers, that practically all of the perfume materials exercise a preservative action on soaps, keeping them sweeter than they would be if no perfume material was used. The manufacturers of toilet soaps include the largest perfumers in the world and the chemical study of perfume materials has come within the province of the soap manufacturer, while some of these manufacturers have entered the field of the distillation of essential oils and the manufacture of synthetic perfume materials. The successes which have been realized in the soapmaking industry through the aid of chemistry and engineering have been of inestimable value but they are not final. The practice in this industry, however much it may have been improved, has not been perfected, and the wide-awake manufacturer is more than ever convinced by each new improvement that chemistry and engineering must be employed and followed if continued success is to be realized. COLGATE & COMPANY, JERSEYCITY, N. J.
CONTRIBUTIONS OF T H E CHEMIST T O T H E PERFUMERY AND ESSENTIAL OIL INDUSTRY By EDWARDT. B E ~ S E R Perfume Chemist, F.
W.Fitch Company
As in many other fields, the contributions of the chemist to the domain of perfumery constitute a glorious romance which would fill many volumes of no small size. Once secluded to the adornment of the royalty, perfumery has been augmented in volume and lowered in cost until today the most meager toiler may revel in “amber scents of odorous perfume.” This is due to the many improvements manu-
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facturing processes have undergone and our advanced knowledge of chemistry. The synthesis of flower oils has, without a doubt, been the greatest achievement made in elevating the a r t of perfumery. With all due credit, however, t o the perfumer, without whose highly trained sense of smell perfumery perfection could not be attained, yet when it comes t q making plain extract of civet cat masquerade as the delicate perfume of a spring Nosegay, we have just simply got t o hand it to the chemist. Through his untiring efforts we need no longer depend upon cow dung, or the vomit of the whale as the source of ambergris, but ambrein, the odor constituent of ambergris, in a fine state of perfection, is now produced in the laboratory, and from substances which have a very different effect upon our gustatory functions. One of the first synthetic materials to find successful application in perfumery was vanillin-the flavoring constituent of vanilla beans. In 1876 Tiemann took out his first patent ona process to produce this methyl ether of protocatechuic aldehyde by means of the acetylation of eugenol and its subsequent oxidation. The first vanillin sold for nearly $800 per pound. Through advances in chemical discovery, improved manufacturing processes, increased consumption and the opposition of rival patentees this price has been gradually reduced until today vanillin can be bought for less than one one-hundredth the introductory price. A later discovery which gave renewed impetus to the industry of synthetic perfumery was that of Tiemann and Kruger. These chemists, after many years of patient research, finally succeeded in preparing a n artificial violet perfume which they called ionone. Ionone was formed by condensing the olefinic aldehyde citral with acetone. The olefinic ketone in the presence of alkalies formed pseudoionone of the formula CI~HUIO.By inversion with dilute acid pseudoionone was converted into ionone. This methyl ketone, a straw-colored oil, had such a powerful violet odor that one pound of it was equal to the perfume contained in all of the violets that you could pack into a fair sized room. Perfumers who, up t o the time of this discovery, refused to admit the value of synthetic perfumes, were soon won over by the exquisite rendering of the violet made possible with this valuable chemical invention. In rapid succession, one discovery followed another, until to-day the modern perfumer can choose from several hundred important aromatic chemicals and produce thousands of fine combinations satisfying to the most fastidious. Synthetics have made possible the perfection of many old perfumes and enable the perfumer to produce new scents undreamed of heretofore. As mere traces of impurities will often seriously alter the basic odor of a synthetic perfume, it must, besides being chemically pure, respond to the olefactory test. And while the sense of smell in man is inferior to that developed in animals, it is nevertheless marvelously delicate. It has been found t h a t air containing one twenty-three billionth of a milligram of mercapt a n to the cubic centimeter could be detected, and it was estimated that only one four-hundred-sixty millionth of a milligram of this substance was necessary t o excite the sensation of smell. So, to pass the cultivated nose, great care is exercised by the chemist to free his laboratory creations from detrimental impurities. Few of the natural flower oils are made up of a single aromatic substance, but are very complex, some oils having upwards of half a hundred individual constituents. Some of these constituents, while having a decided effect upon the character of the complete odor, are present in minute traces only, making recognition exceedingly difficult. But in spite of these many handicaps the chemist has produced a number of artificial flower oils which compare favorably in quality, are always uniform, and in every instance very much cheaper than the oils extracted from the flowers.
