INDUSTRIAL A N D ENGINEERING CHEMISTRY
190
resdts obtained in the same manner by direct analyses. The lecithin-phosphoric acid content of the finished whole egg or yolk noodles when determined directly by Juckenack’s method constitute 50.7 and 52.4 per cent, respectively, of the values in the second column of Table 11. Table 11-Lecithin-PnOs ((1)
Computed from amounts in SUBSTANCE comDonents Whole egg noodle O:ll25 Yolk noodle 0.1290
from LiDoids
(a)
Determined directly 0.1132 0.1308
Percentage
(a) is of ( b )
99.4 98.6
Summary and Conclusions
1-The Juckenack method for the determination of lecithin-
P,05 in egg noodles gives results which constitute about 65
Vol. 17, No. 2
per cent of the lecithin content of noodles as computed from the lecithin-PsOs content of their component materials, also determined by the Juckenack method. 2-The check results between the PZOS content of the lipoids of composite materials, extracted directly by the ammoniacal alcohol method and their PZO6 content as computed from the P~06contained in the lipoids, similarly extracted from their component substances, indicate that the total phospholipin content of cereal products may be estimated by determining the total P206of their lipoids, extracted by the ammoniacal alcohol method. 3-Lecithin-PpO6 values by the Juckenack method constitute about 50 per cent of the P205 of the lipoids extracted by the ammoniacal alcohol method.
The Agricultural Value of Some of the Newer Nitrogenous Fertilizers’,’ By J. G. Lipman and H. C. McLean N E W JERSEY AGRICULTURAL
EXPSRIMEXT STATIOX.
NEW
BRL‘NSWICK, N.J.
ECENT progress in These examples will suffice Among the newer synthetic nitrogen fertilizers amthe art of nitrogen to indicate that problems monium phosphate, ammonium chloride, and urea give incidental to the use of these fixation is of interest promise of great usefulness. They will be employed to materials must be taken to farmers, as well as to best advantage when due consideration is given to factors under consideration. c h e m i c a l engineers and of soil, crop, and climate. The crop value of any economists. New p r o d The method of application and distribution should be n i t r o g e n o u s fertilizer is ucts, as they appear on the such as to avoid interference with germination and injury. directly affected by what market, are taken under to the young plants. may be termed “internal” careful scrutiny by our exIn the preparation of fertilizer mixtures incompatible a n d “ e x t e r n a l ” factors. periment stations and their materials should not be employed. The former have to do with crop value is determined by High nitrogen content, slight hygroscopicity, nontoxicthe nitrogen content of the comparison with such standity, and suitability for mixing with a wide range of ferproduct, the readiness with ard nitrogen fertilizers as tilizer materials make pure urea peculiarly desirable which it will undergo physnitrate of soda and sulfate among the synthetic nitrogen products. ical and chemical change in of ammonia. Comparative the soil, its physiological revalues are ultimateiy established by means of pot and field experiments made under condi- action, and the presence init of substances toxic to planis. The tions varying as to crop, soil, season, and climate. The way is latter concern the conditions of soil, crop, season, and climate thus cleared for the commercializationof any material that has under which any given nitrogenous material is to be utilized. intrinsic merit and is economically within the farmer’s reach. Internal Factors Even a cursory study of the market will show that a fairly substantial number of synthetic nitrogen products are now In gaging the significance of any of these factors one must being offered for agricultural uses. For instance, the mate- consider certain fundamental relations. Everything being rials made in commercial quantities by the Badische Anilin equal, a material containing, for example, 10 per cent of und Soda Fabrik include ammonium sulfate-nitrate, potas- nitrogen is relatively less valuable than one containing 20 sium-ammonium nitrate, ammonium sulfate, ammonium per cent of nitrogen, even though this constituent in the two chloride, sodium nitrate, and urea. The first two are mixtures products is sold a t the same price per unit. The difference of ammonium sulfate and ammonium nitrate, and of potas- in favor of the more concentrated product is accounted for by sium nitrate and ammonium chloride, respectively; the others the greater ease and economy of bagging, transporting, and are single salts; and all are of a high degree of purity. The distributing the latter. Hence, among the synthetic nitrogen manufacture in Norway of calcium nitrate, ammonium fertilizers basic calcium nitrate with about 12 per cent of nitrate, sodium nitrite, and sodium nitrate is no longer new. nitrogen would be followed, in order, by ammonium phosNeither is the production, on a commercial scale, of cyanamide phate, sodium nitrate, ammonium sulfate, ammonium chlowhich has been known to farmers for nearly two decades. ride, ammonium nitrate, and urea-the last named containing I n the United States ammonium phosphate, sodium nitrite, 46 per cent of nitrogen. hydrocyanic acid, and ammonium chloride are now being The changes that these products undergo in the soil conmade, directly or indirectly, from atmospheric nitrogen. stitute another important factor. Nitrates are readily soluble in soil water and readily taken up by plants. On the other 1 Presented by J. G. Lipman before the Division of Agricultural and Food Chemistry at the 68th Meeting of the American Chemical Society, Ithaca, hand, they are not fixed chemically and under extreme conN. Y , September 8 to 13, 1924. ditions may be partly leached out of the soil. Ammonium 2 Paper N o 223 of the Journal Series, New Jersey Agricultural Experisalts are temporarily fixed, but easily nitrified. Urea is ment Station, Department of Soil Chemistry
R
February, 1925
,
I N D U S T R I A L A N D ENGINEERING CHEMISTRY
rapidly changed into ammonium carbonate and almost as rapidly transformed into nitrates. The anions of nitrates and the cations of ammonium salts are also significant. It, is well known that in soils prone to accumulate alkali salts sodium nitrate and other sodium salts may be objectionable. I n humid soils ammonium salts may encourage the concentration of hydrogen ions and may thereby increase the lime requirements of the land. I n heavy soils texture and structure may be favorably or unfavorably affected by the nitrogen salts used. Some crops utilize ammonia nitrogen more effectively, while others prefer nitrate nitrogen. Consideration must also be given to the influence of the different nitrogen salts on the activities of soil microorganisms. A modification of these activities and a disturbance of the balance among species of bacteria, fungi, and protozoa are certain to change the rate at which available nutrients are supplied to the crop. The chemical nature d nitrogei fertilizers must be considered from still another angle. Growers of certain crops must be assured that r,he quality of their product will not suffer from the use of fertilizer. Large applications of chlorides are known to depress the yield of sugar in sugar beets and of starch in potatoes. Such applications may likewise cause deterioration ii the burning quality of tobacco. Hence ammonium chloride, one of the most promising of our synthetic fertilizers, has its limitations for certain crops. The different nitrognn fertilizers must be considered, further, in their relation to the rate of ripening of crops. Both nitrates and ammonium salts may be so used as to shorten or prolong the growing period. Moreover, susceptibility to the attack of fungi and bacteria may also be modified by nitrogen fertilization. I n the preparation of mixed fertilizers due thought must be given to the compatibility of the several ingredients. Ammonium salts cannot be safely used in mixtures containing large amounts of cyanamide, of basic calcium nitrate, of potassium carbonate, or of any strongly basic material. Certain precautions must be observed in making up mixtures of nitrates and of acid phosphate. The compounding of ammonium salts and of nitrates with acid phosphate and potassium chloride calls for precautions on the score of the texture of the resulting product and the readiness with which it may be distributed by means of fertilizer spreaders or drills. In the language of the farmer, fertilizer chemicals may “burn the crop.” By this is meant the effect which fertilizer may have on seed germination and on the growth of the young plants. Two factors are involved here. One has to do with water supply, the other with toxicity. When the soil solution becomes sufficiently concentrated the absorption of water by the seed is retarded or inhibited. Germination is thus delayed or prevented. Where large quantities of fertilizer are used locally-that is, in the drill or hill-conditions of this sort arise. It is obvious, therefore, that with such concentrated and readily soluble salts as ammonium chloride, ammonium phosphate, ammonium nitrate, or urea the problem of distribution is a vital one. Even under conditions of intensive cropping 400 pounds per acre of nitrate of soda or 300 pounds of sulfate of ammonia may be regarded as a liberal application. The same amount of nitrogen would be supplied by 135 pounds of urea. Hence dilution with some inert material would be essential, not only to assure uniform distribution, but also to avoid excessive quantities in some spots, interference with germination, and uneven stands of plants. As to toxic effects, the presence of dicyanodiamide (CzHaNa) in calcium cyanamide is believed to account for the many unsatisfactory results obtained in the use of this fertilizer. Guanyl urea sulfate [(CzHeN40)2.&S04.2H20)] is found in commercial urea made from cyanamide by treating the latter with sulfuric acid. It decomposes but slowly in the soil and
191
depresses nitrification processes slightly. Moderate amounts of it do not depress plant growth. Note may also be made here of the possible occurrence of pyridine and of other toxic products in by-product ammonium sulfate and of perchlorates and borates in Chilean nitrates. I n justice to the manufacturers of these products, however, it should be added, that due effort is being made to reduce to a minimum the content of these toxic substances. External Factors
smong the external factors that bear on the efficiency of nitrogen fertilizers, the soil itself plays a prominent role. Sandy soils are notorious for their ready response to applications of nitrogenous manures. Heavier soils may or may not respond. Peat and muck soils often fail to respond. Nitrates are easily reduced in water-logged soils and may do there more harm than good. I n soils well supplied with lime, ammonium salts are utilized mope efficiently than in soils deficient in this constituent. The toxic action of cyanamide may be obscured in heavy land, where under like conditions pronounced toxic effects would appear in light soils. I n dry chalk or limestone soils ammonium salts may show a diminished efficiency because of the volatilization of ammonia. These examples should suffice, therefore, to show the significance of the soil factor in the utilization of nitrogen in fertilizers. The crop factor is often as important as the soil factor. Legumes, because of their nitrogen-fixing power, are largely independent of the supply of soil nitrogen. Early season crops will make a better showing with nitrates than with ammonium salts. On the other hand, the ammonium salts will give relatively better returns with crops having a longer growing season. Some nitrogen fertilizers are better than others for top-dressing or side-dressing purposes. The significance of seasonal and climatic factors may be readily demonstrated. For instance, farmers in northern latitudes find greater differences in the efficiency of nitrates and ammonium salts than do farmers located farther south. Such differencesare accountable by variations in soil temperature, since in cold soils ammonium salts are nitrified more slowly. Soil aeration is another factor of importance, as is that of soil moisture. The amount and distribution of rainfall, the water-holding power of the soil, and the distance of the water table from the surface all serve to affect the extent and degree of utilization of nitrogen fertilizers. Experimental
Experiments with synthetic nitrogen fertilizers were begun at the New Jersey Station in 1907.3 Bacteriological studies carried out in that year showed that large amounts of calcium cyanamide exerted a depressing effect on soil bacteria. I n the spring of 190g4there was started an extensive series of field experiments dealing with the utilization and relative value of a number of nitrogenous fertilizers. Included in the materials under investigation were imported calcium cyanamide and calcium nitrate, as well as nitrate of soda, sulfate of ammonia, and a number of nitrogenous manures of vegetable and animal origin. A report summarizing the results obtained during a period of fifteen years has been submitted for publication in Soil Science.6 At this time it will suffice to say that on the limed portion of the field calcium nitrate gave the best returns, and was followed in the order given by ammonium sulfate, calcium cyanamide, and sodium nitrate. On the unlimed portion of the field sodium New Jersey Agr. Expt. Sta., Rept., 1907, p. 195. I b i d . , Refit., 1909, p. 9. 6 See also Ibid., Bull. 260; Soil Science, 9, 371 (1920). 3
4
192
INDUSTRIAL A N D ENGINEERING CHEMISTRY
nitrate, cyanamide, calcium nitrate, and ammonium sulfate were efficient in the order given. Of the nitrogen applied there was recovered on the limed soils an average of 35 per cent from the sodium nitrate and ammonium sulfate, and 38 per cent from the calcium nitrate and cyanamide. The corresponding amounts on the unlimed soils were 32 and 31 per cent, respectively. With due allowance for inequalities of soil and errors in sampling and analysis, it still remains obvious that the synthetic nitrogen fertilizers gave as good average returns as the sodium nitrate and ammonium sulfate. I n pot experiments carried out in 1912,6 sodium nitrate gave an average recovery of about 52 per cent, ammonium nitrate about 42 per cent, and ammonium sulfate about 30 per cent. Experiments were carried out in 1915 and 1916' with ammonium phosphate made from cyanamide and sold under the commercial name of Ammo-phos. When used in the row for corn, 100-pound applications of Ammo-phos per acre did not depress germination, but slight injury appeared with 150-pound applications. The efficiency of the nitrogen in Ammo-phos was nearly as great as that in sodium nitrate. Later investigations with Ammo-phoss showed that in its effect on germination it is less toxic than nitrate of soda. In 1922 the question was raised with the New Jersey Station as to the agricultural value of urea made from cyanamide by treating the latter with sulfuric acid. It seemed particularly important to determine whether the small proportion of dicyanodiamide and of guanyl urea sulfate (dicyanodiamide in sulfate) found in the crude urea made by this process would depress plant growth. Hence a number of comparative germination and vegetation tests were made in that year with crude urea and several other nitrogenous fertilizers. The germination tests show that with nitrogen applications equivalent to 160 pounds of nitrate of soda per acre germination was not depressed by either pure or crude urea. With applications of nitrogen equivalent to 320 pounds of nitrate of soda per acre crude urea caused a retarded and lessened germination. The tests were made in a sandy loam soil. In a soil of finer texture the injury, under the same conditions, would have been less pronounced. Bacteriological studies carried on a t the same time showed that crude urea had a marked tendency to depress ammonia and nitrate formation in soils of different type. The same was true of commercial cyanamide, but not of chemically pure urea. Vegetation experiments were carried out in conjunction with the tests just described. A series of 38 pots each containing 12 pounds of white quartz sand was employed for the purpose. There were added in each pot 2 grams of acid phosphate, 1 gram of potassium sulfate, 0.25 gram of magnesium sulfate, 0.1 gram of ferric sulfate, and 4 grams of calcium carbonate. There were added, likewise. quantities of different nitrogen fertilizers equivalent, in each case, to 0.5 gram of sodium nitrate. The barley grown in these pots was reduced after germination to a uniform stand of six plants per pot. Information is given in Table I concerning the equivalent amounts of the different nitrogenous materials employed in the experiment. It was observed on January 19 that the barley seed planted 9 days earlier had produced a perfect stand except in Pots 25 and 26, which had received the double quantity of calcium cyanamide. On the whole, the average yields of dry matter, as recorded in Table I, show that the double portions of the nitrogenous materials gave larger returns than the corresponding single portions. Exceptions are noted in the case of cyanamide. Evidently the toxic substances in this material prevented the normal development of the plants. It may also be noted that the larger portion 6
7 8
New Jersey Agr. Expt. Sta., RezX, 1912, p. 206. Allison, S o d Science, 6, 1 (1918). Coe. New Jersey Agr. Expt. Sta., Bull. 376.
Vol. 17, No. 2
of the chemically pure urea did not produce such a large yield of dry matter as the smaller portion. This cannot be ascribed, however, to the presence of toxic substances. Otherwise, it is apparent that ammonium nitrate, calcium nitrate, and urea nitrate gave, on the average, as good results as sodium nitrate and ammonium sulfate. E x p e r i m e n t s Using Various Fertilizers in Quartz Sand ----GRAMS DRY MATTER-Increase over Pot TREATMENT Grams 1 2 Average check 1.10 1.5 1.3 1, 2 No nitrogen Sodium nitrate 8 . 3 5 8.25 0 . 5 ' 8.15 6:95 3, 4 8 . 7 5 10.06 1.00 9.40 8.10 5, 6 Sodium nitrate Ammonium sulfate 6.38 6 . 1 5 0.3735 6 . 6 0 5.08 7, 8 9, 10 Ammonium sulfate 0.7470 1 1 . 3 0 1 0 . 8 5 11.08 9.78 1 1 , 1 2 Dried blood 2.78 4.08 0.5860 5.00 3.15 13, 14 Dried blood 4.83 6.13 1.172 6.15 6.10 0.2260 15, 16 C. P. ammonium nitrate 6.20 7.50 6.50 8.50 0,4500 13.10 1 2 . 1 0 12.60 1 1 , 3 0 17, 18 C. P. ammonium nitrate 0.6647 1 9 , 2 0 Calcium nitrate 8.60 8.70 7.30 8,50 21,22 Calcium nitrate 1.3294 10.00 8 . 5 5 9.28 7.98 23, 24 Calcium cyanamide 0.95 0.3990 0.35 0.00 1.90 25, 26 Calcium cyanamide 0.13 0.7980 0.25 1.17 0.1698 8.10 27, 28 C. P. urea 8 .' 20 6.86 8.15 0.3376 6.58 6.30 29, 30 C. P. urea 5.28 6.85 0.2306 8.35 31, 32 C. P. urea nitrate 7.05 8.70 8.0 33, 34 C . P . urea nitrate 0.4612 12.8 11.96 1 2 . 3 8 1 1 . 0 8 0.1755 35, 36 Crude urea 5.45 5.08 4.70 3.78 37, 38 Crude urea 8.25 0.3510 6.83 8.13 8.00 T a b l e I-Vegetation
As has already been noted, toxic effects of fertilizers will vary with the texture and chemical make-up of soils, as well as with the methods of application. This may be well illustrated by an experiment in which soil instead of quartz sand was employed. Quantities of good sandy soil distributed in pots received additions of acid phosphate, potassium sulfate, and ground limestone a t the rate of 800, 400, and 1000 pounds per acre, respectively. There were also added different nitrogen fertilizers in amounts equivalent to 400 pounds of nitrate of soda per acre. Barley was grown in the soils so treated. The yields of dry matter secured are recorded in Table 11. E x p e r i m e n t s w i t h Various Fertilizers in Soil -GRAMS DRYMATTERIncrease over TREATMENT Gram 1 2 Averaae check 8.90 8.75 No nitrogen 8.60 0 . 3 i n 9.80 9.70 9.75 1:hO Sodium nitrate 8.95 0.20 9.10 8.80 0.2368 Ammonium sulfate 0.83 9.15 0.3714 10.00 9.58 Dried blood 1.53 0.2530 9 . 8 5 10.70 10.28 Calcium cyanamide 0.47 8.10 0.1115 8.45 8.25 Crude urea 1.95 0.1070 10.00 1 1 . 4 0 1 0 . 7 0 C . P. urea 0.85 9.60 9.20 0.1433 10.00 Urea nitrate
T a b l e 11-Vegetation
Pot 1, 2
,;
4 6 7, 8 9, 10 11, 12 13, 14 15, 16 a,
It is evident that in this experiment cyanamide caused no serious injury to the plants, but that crude urea depressed the growth somewhat. Urea nitrate and chemically pure urea gave results at least as good as those obtained with sodium nitrate and ammonium sulfate. These results are therefore in accord with others obtained a t the New Jersey Station.9 The assumption is thus justified that among the more concentrated synthetic nitrogen fertilizers urea is to be commended because of its high nitrogen content, its slight hygroscopicity, and its comparative safety. Urea made directly from ammonia and carbon dioxide is free from toxic substances. Urea made from cyanamide will contzin varying amounts of dicyanodiamide and guanyl urea sulfate. These may cause injury to crops when present in larger proportions. This type of urea, however, may be so made as to contain relatively small amounts of the objectionable ingredients. It should then be an effective nitrogen fertilizer. 0
McGuinn, Sod Sczence, 17, 487 (19241.
General Inorganic Compounds-The Department of Commerce announces that the total production during 1923, for sale, of aluminium and aluminium compounds, and of inorganic compounds not included in special chemical groups, was valued a t $137,721,152. This total represents an increase of 58.6 per cent as compared with 1921, and of 7.6 per cent as compared with 1919.
