'35%
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ical Company amount to 58 distinct substances and the dyes named to nearly zoo. Other of our American solor manufacturers have additional distinctive dye colors as well as many which are the equivalents of those in the list referred to-truly a satisfactory showing for what is practically a newly created industry at the end of the fourth year since the start was made. The Tariff Census of 1917 before referred to makes the following statement: The annual production was reported for the following groups of products made in whole or in part from material derived from coal tar; 45,977,246lbs. of dyes valued a t $57,796,027;5,092,558 Ibs. of color lakes valued at $2,764,064;2,236,161lbs. of medicinal chemicals valued a t $5,560,237;779,416lbs. of flavors valued a t $1,862,456;263,068 lbs. of photographic chemicals valued a t $602,281;and 19,545lbs. of perfume material valued at $125,960. Of course the manufacture of munitions begun on allied account and continued later by the Ordnance Department on our own account, means the production of numerous organic compounds on a scale totally beyond any previous experience. Picric acid, trinitrotoluol, nitrocellulose and nitroglycerin for smokeless powder, fulminate powders, and other preparations are manufactured by tons, but as this is a war industry and not one that will continue, we have omitted it from our discussion. CONCLUSION
What is the outlook for industrial organic chemistry in the immediate future in this country? I would say that it is most encouraging. The exigencies of the war in Europe have caused a widespread search for independent sources of raw materials and with very satisfactory results in many cases. Our large corporations have established research laboratories with the best up-to-date equipment and have planned real and thoroughgoing research in a broad intelligent spirit which does not ask for hasty results but emphasizes the wish for thoroughness. Our Government has recognized in a very satisfactory way its need of chemical service and has thus publicly endorsed the fundamental importance of the chemist in industrial achievement. Capital has come forward willingly in support of properly planned chemical undertakings and thus made the establishment of new industries possible in a way far beyond what had been possible before the war period. Lastly, the disturbed condition of all European trade relations has made it possible for the United States to inaugurate very promising export business in quarters not previously practical or only so under conditions distinctly unfavorable. These new achievements we have every reason to expect to continue in future and no doubt with added momentum. SOLVENTS F R O k KELP B y C. A. HICGINS, of the Hercules Powder Company
The serious shortage of acetate of lime and its derivatives is now causing solvent users considerable anxiety. The past four years have seen a tremendous increase in the demand for acetone, acetic acid, acetic anhydride, etc., for purely war purposes, and this has caused a corresponding diminution in the quantity available for commercial uses. Since the war, acetate of lime has increased to three or four, times its normal pre-war price, and its solvent derivatives such as acetone, ethyl-methyl ketone, acetone oil, acetic acid, ethyl acetate, etc., have advanced correspondingly. Considerable interest has accordingly been shown in the huge kelp or seaweed fermentation plant built and now being operated by the Hercules Powder Company on the coast of Southern California, where acetone, ketones, and a long line of acetate derivatives are being obtained from kelp. This factory, so far as I know, is the only one of its kind in existence. The data are therefore rather limited and resolve themselves into a de-
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scription of the methods and results obtained at this factory b y the Hercules Powder Company. You will realize, therefore, there is no historical background to the manufacture of solvents from kelp. There is, however, record of experiments carried out by Stenhouse in the year 1851, when he produced acetate of lime by allowing kelp to ferment under suitable conditions. While his experiments as recorded in the Philosophical Magazine and Journal of Science did not have any immediate practical application, they contained the germ of an idea which found manufacturing expression about the year 1915. The attention of potash users was rather focused at this time on the huge beds of perennial kelp which stretch along the Pacific coast. About this time, too, the Hercules Powder Company needed acetone, and needed it from an entirely new source. We needed it to make smokeless powder for the British Government. Experimental work was immediately started on the production of acetate salts by the fermentation of kelp. Shortly afterwards ground was broken for a factory capable of producing acetone and ketones from kelp at the rate of about 3 to 4 tons a day with potash and iodine as valuable by-products. The Hercules process of producing solvents and their intermediates from kelp is really very simple. The kelp is mowed and garnered from the marine beds by special harvesting boats. It is then macerated and pumped to the tank a t the factory on shore, where it is diluted and allowed to ferment at about 90O F. with the addition of finely ground limestone to neutralize the acids formed in the fermentation. After a period of about 15 days, the leafy structure of the kelp has been entirely destroyed and a liquor is obtained containing chiefly acetate of lime, muriate of potash, and iodides in solution. The crude salts recovered therefrom by evaporation are heated in retorts to obtain acetone and the muriate of potash is recovered by leaching and crystallization. That is the process in its essentials and stripped of all its details. A glance a t the products chart (page 833) will show, however, that a great many new and additional products have been isolated. In addition to the acetone, ketones, potash, and iodine already referred to, the higher acids of the acetic series are also being produced, together with their ethyl alcohol esters. The fermentation of kelp by the Hercules method is productive, therefore, of not only acetate salts, but also of propionates, butyrates, valerates, and even of the higher acids of this series. It is this series of salts which by conversion into their ethyl esters is providing the trade with an entirely new source of ethyl acetate and an entirely new series of amyl acetate substitutes in the ethyl propionate and ethyl butyrate, which latter have never before been made in commercial quantities for the solvent trade. The principal solvent product of a kelp fermentation plant along the lines developed by the Hercules process must necessarily be acetone and the higher ketones. This is explained by the fact that the bulk of the salts obtained in the evaporation of the fermented kelp liquor already mentioned consists of a mixture of acetate of lime and muriate of potash. By far the simplest and most economical way of separating this mixture or realizing the values of both salts is to heat the mixed salt in retorts. Acetone is thereby obtained, and muriate of potash and calcium carbonate is left behind as residue. The potash is leached from the insoluble calcium carbonate and recovered by crystallization. In the process of concentrating the fermented liquor, however, a scum collects on the surface of the liquid. This scum consists of a mixture of calcium acetate, propionate, butyrate, valerate, etc., all of which are less soluble in hot than in cold s o h tion. This scum holds very little of the potash and can accordingly be used in the manufacture of solvents such as esters, where the recovery of any residual potash salt would be difficult.
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Use is therefore made of this scum or “taffy,” as i t is called by the workmen on account of its plastic nature when hot, in the manufacture of solvent esters which are in such demand in the soluble cotton and lacquer industries. The taffy is mixed with ethyl alcohol and sulfuric acid and the resultant esters separated by fractionation. A word now as to the nature and uses of these solvent esters. Ethyl acetate is an old friend among us. Its use as a solvent of soluble cotton or nitrocellulose in the manufacture of imitation leather, in finishing celluloid, and in a thousand and one other directions are too widely known to need mention. Ethyl propionate and butyrate are not so widely known. Several investigators have mentioned their excellence as solvents for nitrocellulose gums, resins, etc. Worden, in his “Nitrocellulose IndustryY’mentions this fact and states that the only bar to their use is the high price, or that they are not commercially obtainable. Ethyl propionate boils a t I O O O C. and appears to resemble in its properties a mixture of ethyl acetate with about I O to 20 per cent amyl acetate. Ethyl butyrate boils around 1 2 0 ’ C. a n d resembles amyl acetate very closely in its physical properties. These two esters now produced for the first time in large quantities will doubtless find wide application in the soluble cotton celluloid, artificial leather, paint and varnish trades, where neutral solvents of pleasant odor and possessing a moderately slow rate of evaporation are desired. The use of these esters is also contributing materially a t the present time t o the War Industries Board’s program for the conservation of acetate of lime Special mention might be made of the valerates, caproates, ctc., which are now being isolated in this process. Valerian and its salts and esters are well known to the drug and pharmaceutical trade, to whom a new source a t this time will be welcome, while the esters of these acids will doubtless be much sought after by the essence and perfume trade. The kelp industry is in its infancy, and although somewhat of a war baby, it has in it the makings of a vigorous adult. Heralded as the savior of potash users, i t has come to the aid of users of high-grade solvents and pharmaceuticals, and bids fair in the future to continue to develop new and valuable organic chemicals.
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W O O D WASTE AS A SOURCE O F E T H Y L ALCOHOL By G. H. TOMLINSON
Manager, Kinzinger Bruce and Co., Ltd., Niagara Falls, Ontario
For some years we have been hearing more and more regarding waste wood as a source of ethyl alcohol. The amount which is thus being made, however, is still but a fraction of the nation’s supply and within the past few years has not been extended, irrespective of the great and increasing demand which the war has developed. It may be advanced that sufficient capital is available and competent technical skill can be secured and if the proposition is therefore all that has been claimed, the question naturally occurs, why has more rapid progress not been made? Is the proposition fundamentally unsound or does it still offer the very considerable possibilities which have been predicted? We all realize the distance to be traveled between the discovery of a chemical reaction and its successful commercial development and application. In this case, as a matter of fact, IOO years have already elapsed. The pitfalls to be crossed, both technical and commercial, aye legion, and the more unusual, attractive, or revolutionary the proposition may be, the more difficult may its pathway become. Premature development and extravagant or unsound exploitation can prostitute an undertaking, no matter how promising i t may be, and when this occurs
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in connection with a process, which has not been already established, disaster is invited. I think I may safely say that such a condition of prostitution represents the present status of this particular industry, and explains to a large extent its present position of apparent stagnation, even a t this time when its further development should offer such unusual opportunities. I n this connection the several company flotations which have occurred have been initiated by promoters having no particular interest in the business itself. This has resulted in only a small portion of the relatively large amount of capital which has been raised in connection with the undertaking filtering through for its actual development. Adequate research has not been undertaken, the plants, which already have been constructed, have been started prematurely in locations having little regard to the commercial conditions involved, all in order that a rapid showing might be realized, and a quick turn made by the promoters. Any complete consideration of this aspect of the proposition can only lead to the conclusion that the miracle is that anything has survived. The fact, however, that several million gallons of alcohol have actually been produced from this source, and that a t least two plants have been operating more or less continuously over a period of years, irrespective of the technical and commercial handicaps from which they still suffer, justifies the belief that ultimate success is established, and that the undertaking offers much promise for the future. It was originally assumed that almost every sawmill represented a possible location for the establishment of such a plant. Since there were almost innumerable sawmills a t which the disposition of wood waste was a problem, even constituting in most an element of expense, it was also assumed that this material could be purchased a t a purely nominal figure. It therefore seemed logical that favorable contracts for wood waste could be made and having sufficient capital, the company controlling the process could establish an endless chain of plants producing ethyl alcohol, and thus soon secure entire control of the alcohol market. On this basis and plan the business was projected. I t was soon found, however, that while there was no question regarding the number of sawmills or the extent of the wastewood which is produced, there are nevertheless, very few a t which conditions are entirely favorable for the establishment of the extensive plant which the manufacture of ethyl alcohol requires. The life of the lumbering operations may be uncertain, the water supply deficient, labor or transportation conditions unfavorable, or any one of a number of such factors may be found which jeopardize success. The fact that sawdust and all the other forms of waste wood are so bulky and difficult to handle precludes transportation, and therefore confines its processing to the point at which its production occurs. When approached, the lumberman who has a suitable location soon recognizes the advantage which he enjoys, and any outside company wishing to do business must pay. his price; and if once established, has no other source of supply. It can at once be seen that any large or general development along these lines was impractical and bound to fail. In the manufacture of our lumber we know that many millions of tons of waste wood are annually produced, and the potential asset which this waste represents is being recognized. If any considerable part of this, however, can be converted into alcohol, there is probably no more important industrial use which it can be made to serve. That this can be done in a limited way has now been completely proved, but in order to greatly extend its application, the development, it would seem, must follow different commercial lines from those along which the start was made. The process which has been developed naturally divides itself into two very distinct and separate steps: We first convert a
