AUGUST, 1938 119) (20) (21) (22) (23)
INDUSTRIAL AND ENGINEERING CHEMISTRY
Holluta, H., “Die neueren Anschaugen uber die Dynamik und Energetik der Kohlensaure-Assimilation,”Stuttgart, 1926. James, W. O., Ann. Botany, 44, 173 (1930). James, W. O., and Penston, N. L., Ibid., 47, 279 (1933). Johnston, E. C., and Hoagland, D. R., Soil Sci., 27, 89 (1929). Kostytschew, W. S., and Eliasberg, P., 2. physiol. Chem., 111, 228 (1920).
(24) (25) (26) (27) (28) (29) (30) (31)
132) (33) (34) (35)
Loew, O., E r t l h . Pflanze, 30, 141 (1934). Loew, O., U. 5.Dept. Agr. Plant Ind., BUZZ.45, 34 (1903). Lundegardh, H., Soil Sei., 40, 89 (1935). Merkenschlager, F., Erndh. Pflanze, 25, 275 (1929). Murneek, A. E., and Gildehaus, E . J., Mo. Agr. Expt. Sta., Bull. 310 (1931). Noack, K., Ern&h. Pflanze, 32, 353 (1936). Noack, K., and Schmidt, O., Z . Botan., 30, 290 (1936). Pohl, R., and Pringsheim, P., “Die lichtelectrischen Erscheinungen,” Braunschweig, F. Vieweg & Sohn, 1914. Raper, H. S., Biochem. J.,20, 735 (1927). Remy, Th., and Liesegang, H., Landw. Jahrb., 64, 213 (1926). Richards, F. J., Ann. Botany, 48, 515 (1934). Richards, F. J., and Templeman, W. G., Ann. Botany, 50, 367 (1936).
889
Rohde, G., 2. Pjlanzenernahr Dtingung Bodenk., 44, 1 (1936). Russell, E. J., “Soil Conditions and Plant Growth,” 6th ed., p. 90, New York, Longmans, Green & Co. 1932. (38) Scharrer, K., and Schropp, W., Erntlh. PRanze, 32, 312 (1936). (39) Shaw, J. K., Mass. Agr. Expt. Sta., Bull. 305, 50 (1934). (40) Snow, A. G., Jr., Plant Physiol., 11, 583 (1936). (41) Steward, F. C., Protoplasma, 18, 208-42 (1933). (42) Stoklasa, J., Biederinanns Zentr., 61, 161 (1932). (43) Stoklasa, J., Erndh. Pflanze, 30, 299 (1934). (44) Ibid., 32, 2 7 (1936). (45) Stoklasa, J., Z . Zandw. Versuchsw., 11, 52 (190%). (46) Tottingham, W. E., Am. Potato J . , 13, 297 (1936). (47) Vogel, F., Ernah. P R a n z e , 29, 457 (1933). (48) Wallace, T., Univ. Bristol, Ann. Rept. Agr. Hort. E r p t . Sta., (36) (37)
1921, 136. (49) (50) (51)
Warburg, O., Riochem. Z., 100, 230 (1919). Warne, L. G. G., Ann. Botany, 48, 57 (1934). Wilfarth, H., and Wimmer, G., Arb. deut. Landw. Gesell., 68
(52)
Wlodek, J., Bull. acad. polonaise sei. lettres, classe sci. math.
(1902). nut.,
[ B ]1921, 19.
RECEIVED May 4, 1938.
POTASSIUM SALTS A S CHEMICAL RAW MATERIALS J. W. TURRENTINE American Potash Institute, Inc., Washington, D. C. LTHOUGH the economic and social significance of potash salts in the channels of world commerce is commonly associated with their value as essential ingredients of commercial fertilizers, they are equally essential as raw material of the more strictly designated chemical industries. Potassium chloride may be considered the parent salt from which all other potash salts of commerce are derived. While this comprehensive statement is subject to some modification, it, will serve as the starting point from which to trace the source of potash salts as chemical raw materials. Potash refineries produce potassium chloride predominantly and, in this country, practically exclusively. In Germany where magnesium sulfate is a constituent of the raw materials processed, potassium sulfate and the double salt (potassium magnesium sulfate) are also produced through the interaction of potassium chloride and magnesium sulfate. I n the plants of affiliates, potassium nitrate is yielded from potassium chloride and nitric acid, and potassium carbonate by way of the Engel salt reaction. In France potassium sulfate is manufactured from potassium chloride and sulfuric acid. The potash industry, therefore, may be said to provide the chloride, sulfate, nitrate, and carbonate of potassium as raw materials of, or as primary materials for, the chemical and process industries.
A
THE extent to which potassium salts enter these industries within the United States is shown by citing the sales of the chemical grades, of domestic and foreign origins during the calendar year 1937-namely, 32,400 short tons, made up principally of 30,700 tons of high-grade muriate (chloride) of 98100 per cent purity. If considered alone, this figure appears fairly impressive, but when compared with the total of potash salts sold and delivered within the United States during 1937 (1,100,000 short tons) the former oategory, representing only 3.2 per cent of the total, appears rather insignificant.
The sales of chemical grades of potash salts since 1929 (in short tons) were as follows: 1929 1930 1931
9,437 12,070 8,713
1932 1933 1934
8,467 13,824 13,734
1935 1936 1937
29,074 29,335 32,358
Potassium chloride finds a diversity of uses in minor quantities, but its major consumption is in the electrochemical industries for conversion principally into caustic, a considerable part of which is, in turn, converted into potassium carbonate. According to the 1935 census of chemical manufactures (the latest figures available), potassium hydroxide of 88-92 per cent concentration produced for sale amounted to 9600 tons, and potassium carbonate amounted to 5860 tons. During the same year 1540 tons of caustic and 1850 tons of the carbonate were imported, representing a domestic market in that year of 11,000 tons of caustic and 7700 tons of cartonate. During 1937 imports of these two commodities were 1136 and 787 tons, respectively. This decline in imports, considered in the light of an increase in sales of chemical grades of muriate and a probable increase in the use of caustic and carbonate, would indicate a corresponding increase in the domestic production of each. CAUSTIC potash is produced as the finished product in the solid, flake, broken, and ground forms of 88-92 per cent concentration, and in solution form of 45-50 per cent concentration. Increasing amounts of caustic are being delivered in the form of solution in 8000-gallon tank car lots; on delivery they are discharged directly into storage tanks, to be drawn off as needed. Thus, economies are effected in evaporation, redissolving, handling, and containers to offset the increase in bulk. Perfection in manufacturing process and in tank car construction, particularly linings, makes possible the delivery of such solutions uncontaminated by impurities such as iron, copper, sulfates, and chlorides.
890
INDUSTRIAL AND ENGINEERING CHEMISTRY
Approximately 50 per cent of all caustic potash finds its application in the manufacture of potash soaps. The yield (in 1935) was 67.5 million pounds of textile soap, 19 million of liquid soap, and 20.5 million of soaps otherwise designated. The remaining 50 per cent is consumed (in the order of decreasing importance) in the manufacture of dyes and synthetic organics (2000 tons), the production of fine chemicals, carbon dioxide absorption in air liquefaction, the textile industry, and glass manufacture. POTASSIUM carbonate is being made in increasing amounts, as indicated by the fact that its production was reported by the Bureau of the Census in 1935 for the first time by three or more manufacturers. Both the hydrated and calcined carbonates are offered in several grades, degrees of purity, crystal types, and particle sizes. As in the case of the caustic, the carbonate is offered also in solution form of 47 per cent concentration for tank car delivery. The carbonate, like the caustic, is used principally in the production of soaps and chemicals (approximately 65 per cent). I n glass manufacture it is still the preferred source of potash, some 35 per cent of the total being destined for this use. The manufacture of potassium carbonate from caustic potash by the electrochemical industries is an interesting new development apparently meeting with substantial success. The demand for electrolytic chlorine in excess of that of the equivalent caustic soda concurrently produced would appear to warrant an exploration of the industrial chemical field to determine if there are not other derivatives of caustic potash which could be profitably exploited as a further outlet for that valuable commodity. The abundant supplies of highly refined potassium chloride now available, combined with the cheap electrical energy now promised, would appear to warrant such a survey.
IK T H E applications mentioned for potash salts as chemical raw materials, the potash salts are used because of inherent properties not possessed by their formidable competitors, the lower priced sodium compounds. But even in many applications where this difference is less important, potash is still preferred, particulariy as a base for the neutralization of acids to form the many sa& which find their way into a vast number of chemical applications. I n such compounds the potassium constituent lends stability, preferred solubilities, crystal forms, or other desirable characteristics which make it more desirable from both the manufacturing and the use viewpoints. T o attempt to trace these compounds through the ramifications of chemical industry would lead us into a maze of detail beyond the scope of this paper. The Oil, Paint and Drug Reporter listed over a hundred commercial potassium salts (July 16, 1934) and three columns of applications (September 6, 1937). While these salts are characterized more by their numbers than by their tonnage output, the latter is worthy of note in several instances. Among such salts produced domestically or imported in major quantities in 1935 were those listed in Table I. In the press, potash salts are frequently referred to as commodities of great military importance. This is undoubtedIy true in the sense of the adage that “an army fights on its stomach” and that in time of war more food is required with fewer to produce it. In the foregoing discussion of potash salts as chemical raw materials, however, it is not immediately apparent just what compounds enter the peacetime chemical industry to be expanded in wartime. Potassium nitrate is frequently referred to as essential in the manufacture of slow-burning black powder, used in fuses
VOL. 30, NO. 8
and in the ignition of smokeless powder. One is surprised to find that in 1937 the imported 1164 tons supplied this peacetime demand as well as the other uses to which in the past i t had been applied.
TABLE I Domestic salt 1000 Zb. Potassium acetate Potash alum Potassium chrome alum Potassium chromate and bichromate Potassium citrate Potassium iodide ImDorted salt Potassium chlorate and perchlorate Potassium cyanide Potassium nitrate Miscellaneousa
4,491 7.4.7fi . ,--. 2,666 4,491 175 433 14,316 99 2,327 295
Value $359,366
-1.52 -,QAR - -I
156,684 298,310 65,361 572,161 752,000 38,780 56,910
194,726
Includes principally potassium chromate and bichromate, ferri- a n d ferrocyanide and permanganate. Q
The 1937 importation of 7000 tons of potassium chlorate and perchlorate indicates a substantial demand for that commodity which would be greatly increased to meet the wartime needs of the great variety of pyrotechnics, primers, and contact explosives, such as hand grenades, used for military purposes. This tonnage, when compared with the 10-year average of 6700 tons imported, indicates a stable peacetime demand. The optical glass industry would undoubtedly undergo a wartime expansion and thus increase the consumption of potassium carbonate or hydroxide, an essential raw material in that industry. The tartrates enter prominently into the totals of potassium salts of domestic and foreign origins. I n 1935 we imported 8200 tons and produced 1900 tons, a total of over 10,000 tons for domestic requirements. In 1937 we imported some 12,000 tons in the category of “argols, tartar, and wine lees.” These items, however, are scarcely pertinent to the present subject since the potassium represented is a natural ingredient, and they find use principally as an ingredient rather than as a chemical reagent or as a raw material for further processing. I n the ceramics and glass industries in 1935, 195,000 tons of feldspar were employed. While frequently regarded as a source of essential potash, its theoretical content of silica is 65 per cent. Therefore feldspar can more accurately be regarded as a source of silica than of potash, of which the theoretical content is 17 per cent potassium oxide, but the actual is nearer 12 per cent. On the basis of the latter figure this tonnage represents 23,000 tons of potassium oxide. I n view of the price of $11 to $17 per ton with freight to be added, the question is being asked among ceramic chemists : Are there not cheaper sources of all three ingredients, potash, alumina, and silica? This leads to the consideration of possible substitutes, synthesized from low-cost potash salts and cheaper forms of alumina or silica, as a conveyor of potash in the manufacture of glass, enamels, and glazes. The size of the potential market would appear to justify the thorough survey of the possibilities of such a synthesis and substitution. Chemical industry now has a t hand plentiful supplies of potassium chloride of a high degree of purity and a t relatively low cost as the raw material from which to produce the vast assortment of derivatives used in innumerable applicatiom throughout industry. Increasing sales show that this fact is winning wide appreciation. RECEIVED April 27, 1938.
