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ciable loss of nitrogen in the evolved gas. The process of preparing potassium nitrate from potassium chloride and nitrogen peroxide thus becomes a cyclic one when operated in connection with a plant for the absorption of nitrogen peroxide. As thus operated the process consists in passing a nitrogen peroxide-air mixture countercurrently over a potassium chloride solution in absorbing towers to form a solution of potassium nitrate in strong nitric acid, digesting the recovered solution under a reflux condenser with solid potassium chloride equivalent to the free nitric acid present,
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cooling to crystallize out high-grade potassium nitrate, and returning the mother liquor to the absorbing system for use again in the process. The chlorine and nitrosyl chloride evolved in the digestion with potassium chloride may be separated by passing over concentrated sulfuric acid. The nitrogen of the nitrosyl chloride is thereby absorbed as nitrosyl sulfuric acid and may be recovered as nitrogen peroxide in the usual way for return to the absorbing system. The products of the process are thus potassium nitrate, chlorine, and hydrochloric acid.
The Fertilizer Triangle’ Firman E. Bear THEOHIOSTATEUNIVERSITY, COLUMBUS. OHIO
On January 5 and 6, 1928, the Middle West reprelist. I n 1927, of 185,388tons sentatives of the fertilizer industry and of agronomists ing the list of fertilizer of mixed fertilizer sold, 111,adopted the triangle principle as a means of choosing a analyses that are being 329 tons, or 60 per cent, belist of fertilizer ratios in a program of standardization. offered for sale has engaged longed to the standard list of This principle involves the use of an equilateral trithe attention of the fertilizer analyses. angle, the points of which represent 100 per cent nitroindustry and of agronomists M e a n w h i 1e developments gen, phosphoric acid, and potash, respectively. All for a number of years. The of considerable significance possible ratios of any two or all three of these lie within first general conference called had taken place in the fertithe boundaries of this triangle. to consider this matter took lizer industry. Double superThe problem involved is that of spacing the ratios in place in Chicago, October 19 p h o s p h a t e s containing 45 the triangle in such a manner as to cover the field and 20, 1922. At this conto 50 per cent of available equally well at all points. By drawing a series of nine ference there were present repphosphoric acid were being equally spaced lines parallel to each side of the triangle, offered for sale in quantity: resentatives of the fertilizer the intersecting points of these three series of lines industry and a g r o n o m i s t s Ammonium phosphate conmay be so located that they accomplish the purpose from Ohio, Indiana, Illinois, taining nearly 15 per cent of desired. Such a system of selecting ratios is parammonia and 60 per cent of M i c h i g a n , Wisconsin, and ticularly important in connection with the movement phosphoric acid was available Missouri. A list of fourteen from low to high and to concentrated analyses. Its use for purchase. Synthetic nianalyses was finally adopted. is urged for consideration by those concerned with the trogen materials were being The agronomists agreed to development of the fertilizer industry as a means of produced in large amounts, of c on f i n e their recommendasimplifying the program of standardization and elimiwhich the most concentrated, tions of mixed fertilizers to nating confusion on the part of the consumer. urea, contained 55 per cent of this list. The fertilizer proammonia. Large amounts of ducers agreed to feature these analyses-and to withdraw all others from their offerings as high-percentage potassium salts were available, ;ne of which had a potash content of 60 per cent. soon as it could be accomplished. It was evident that fertilizers which had been classed as The list chosen represented a compromise between the industry and the agronomists. The former, by reason of “high-analysis” were relatively low in analysis as compared established trade in certain analyses, wished to continue to with those which might be produced if the demand for them take advantage of the demand that had been created for them. should develop. Farmers were becoming interested in posThe latter, taking into consideration the matter of economy sible saengs of freight and handling charges that might be to the fertilizer user, desired higher analyses than were being effected in the use of these concentrated analyses. I n 1927, produced in quantity a t that time. However, no particular 1210 tons of 3-18-3 and 1674 tons of 4-244-one and onedifficulty was experienced in reaching an agreement, since half and two times the concentration, respectively, of the both groups recognized that there was no longer any valid standard 2-12-2 analysis-were sold in Ohio. Meanwhile excuse for the production of 1-8-2 and similar low analyses one of the producers of synthetic nitrogen was advertising a series of complete fertilizers called Nitrophoskas, one of that normally contain considerable amounts of filler. Following the Chicago meeting, other regional conferences which analyzed 18-30-15. With the production of concentrated materials came, not were held for the New England, the Atlantic Coast, and the Southeastern states. The lists of analyses chosen a t these only the possibility of producing much higher analyses, but a greater variety of them than before. Anticipating this four conferences are given in Table I. The success of these efforts a t standardization can be seen development, conferences of representatives of the fertilizer from data of fertilizer sales in one of the cooperating states, industry and agronomists were again called for the purpose of which Ohio is chosen as an example. Of 110,585 tons of of considering what modifications of the standard lists of mixed fertilizer sold during the year preceding the conference, analyses were desirable. Early in the discussion of this problem it became evident 1922, 16,630 tons, or 15 per cent, were analyses of the adopted that the best procedure was to reconsider the whole matter 1 Presented before the Division of Fertilizer Chemistry at the 76th on the basis of nutrient ratios. Assuming that B ratio of Meeting of the American Chemical Society, Swampscott, Mass., September ammonia t o phosphoric acid and potash of 1-3-1 was needed 10 to 14, 1928.
HE problem of simplify-
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for the profitable production of increased yields of some crop, the fertilizer industry might then proceed in the preparation of whatever analysis of this ratio it could deliver to the farmer a t the lowest cost per unit of plant nutrients. By eliminating fractional percentages and adopting a minimum analysis, a relatively simple solution was possible. Table I-Fertilizer Analyses Chosen i n First Regional Conferences (Expressed as percentages, or units of total ammonia "(a) available phosphoric acid (PzOs), and water:soluble potash (KzO), rebpectively) ATLANTIC SOUTHEASTERN NEW CENTRAL STATES STATES STATES ENGLAND 0-12-6 2-12-4 2-12-2 4-8-6
.... .... . .. . . .. . ....
4-12-0 0-10-10 3-12-4 3-8-6 2-12-6 2-14-2 2-16-2 0-14-4 0-8-24 2-8-16
0-12-6 2-12-4
. .. . 4-8-6 4-8-4 3-10-6
....
....
..... .. . .... 3-10-4 5-4-5 5-8-7 8-6-6
.... .. .. .. .. ....
0-12-6 2-12-4 2-12-2 4-8-6 4-8-4 3-10-6 3-8-3 7-6-5 4-12-4 4-12-0 0-10-10 2-10-6 6-8-4 5-10-5 3-8-8 5-8-5
0-10-4 10-5-0 4-8-10
Principle of Fertilizer Triangle
0-12-6 2-12-4 2-12-2
.... . .. .
4-8-4
3-8-3 7-6-5 4-12-4
.... ....
2-8-4
. ... . ... . ... .... .. .. .. .. . ...
(Po Figure 1-Fertilizer Triangle Showing Location of 2-6-2 Ratio a t P o i n t A a n d 5-8-7 R a t i o at P o i n t B
the bottom, six lines from the left side, and two lines from the right, the ratio represented by that point is 2-6-2. The sum I n selecting fertilizer ratios such as are required to cover of these figures always equals 10. the field of fertilizer need, difficulties arise in the choice beNofc-By agreement, subsequently ratified by resolution of the Naratios* In common Of the large number Of tional Fertilizer Association, the first figure represents N , rather than "a, the writer had given this problem a the second PzOj, and the third KzO. In the Southern states the order of with many Other great deal of consideration for many years without having statement has long been P ~ O ~ - Nor NH-K~O. come to a satisfactory solution. Previous to the second To determine the location in the triangle area of any given Chicago conference] held January 5 and 6, 1928, it OCCurred fertilizer analysis, one has only to factor the ratio in such to him that use might be made of the triangle principle in may that it yields a sum of 10. Thus a 5-8-7 analysis has selecting these ratios. The conference agreed and the prin- the ratio 2 1 / ~ 4 - 3 1 /and ~ can thus be located without difficulty. ciple was adopted, selection of fertilizer ratios being made Analyses Adopted at Regional Conferences as Shown by accordingly. Triangles When three variables are involved] all possible ratios of these three are included within the boundaries of an equiExamining the four lists of analyses originally adopted a t lateral triangle the points of which each represent one of the the regional conferences in 1921-22, one has the picture variables when taken at 100 per cent. Any particular ratio can be located in this area. It is thus possible to study the relationship to each other of a series of ratios which might be selected. I n the probleminvolved with fertilizers] it is desirable so to space these ratios with reference to each other that the field of fertilizer need is covered equally well a t all points. The intersecting points of series of equally spaced lines drawn parallel to each of the three sides of the triangle, meet the requirements for the problem at hand. The question remains as to how many of these parallel lines shall be drawn. By having Figure 2-Central States Figure 3-New England States ten parallel lines in each series, the ratios represented by the intersecting points are, in effect, percentages. That is, the sum of the three can be made to equal 10 or 100, as one may desire. This scheme of locating the points was chosen by reason of convenience and also because a number of the ratios chosen by this scheme are identical with those in certain popular analyses being offered for sale. By examination of Figure 1it will be noted that the bottom line represents zero nitrogen (N); that on the left side, phosphoric acid (P,OJ; and that on the right, potash Figure 4-Atlantic Coast States Figure 5-Southeastern States (K2O). Taking the Point two lines above Distribution of Ratios of Fertilizer Analyses Adopted at First Regional Conferences
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-
-
Figure 6-Central States Figure 7-New England States Fertilizer Ratios Adopted b y Use of Triangle Principle a t R e c e n t Regional Conferences
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given consideration (Table II), one has the picture presented by Figures 6, 7, 8, and 9. It will be noted from these that the C e n t r a l a n d the New England states adopted the triangle principle in locating the ratios chosen. The other two groups of states did not. It is to be hoped that the last two groups of states may find it possible to give the principle consideration a t an early date in the interests of a national program of standardization. It would not be expected that the same ratios would be chosen in any two groups of states. It is conceivable that only two or three of the ratios chosen in the Central states would be deemed necessary in the Southern states. However, it seems probable that certain ratios near the center of the triangle would be included in all the lists adopted, with the result that some interesting comparisons of the effects of the same ratio when used under a wide variety of soil, crop, and climatic conditions might be made. Manner of Using Triangle
The triangle principle is useful in experimental work with fertilizers, as Schreiner has well shown.2 One need not be restricted in his choice of ratios in such tests to those that are possible by selecting only the intersecting points on the triangle as constructed. It is only for the Aist that is to be recommended to farmers and offered for sale by the fertilizer producers that the particular triangle scheme outIined is suggested. It must also be agreed that there is no especial reason for selecting the particular number of parallel lines chosen for use in the construction of the triangle, except that of convenience and the fact that the number of ratios permitted by the scheme seems entirely adequate for the needs of those who produce mixed fertilizers as well as for those who are in position to recommend their use. The list of ratios from which those to be adopted may be selected is given in Table 111.
Figure &Atlantic Coast States Figure 9-Southeastem States Fertilizer Ratios Adopted without Use of Triangle Principle a t R e c e n t Regional Conferences
Figure 10-Positions o n Triangle of NitroIv; Ammo-Phos I a n d 11, Diammonphos Potassium Ammonium Nitrate, a n d Nitrate of Potash
phoskas I, 11, 111,
p r e s e n t e d by Figures 2, 3, 4, and 5. It is apparent that much could be done toward spacing the analyses with reference to each other. The same number of analysesproperly spaced would cover the field of fertilizer need m o r e effectively. Small differences in need indicated by the near-
Of certain Of these ratios on the triangles certainly cannot be known to exist with the present intensity of our agriculture.
Ratios Chosen in R e c e n t Regional Conferences ATLANTIC NEW SOUTHEASTERN STATES ENGLAND STATES 2-6-2 2-6-2 2-6-2 1-5-4 1-4-5 214-2 2-4-4 2-4-2 2-5-3 2-4-5 2-5-2 3-4-3 3-3-3 3-4-2 1-7-2 1-6-2 318-3 b 2-8-2 21315 1-4-6 4-3-3 7-6-5 3-5-2 ... 4-2-4 3-8-8 9-5-2 3-9-8 4-4-2 ... .. .. .. ... 2-8-5 3-8-56 ... 5-8-5 5-8-3 1-9-0" ... 5-8-7 5-10-3 0-6-4' . . . 9-8-3 2-4-6 3-9-5 .. 0-2-8 ... 0-5-5 ... 0-4-6 0-12-5 0-7-3 515-0 2-8-00 6-3-0 a Not in original list but added by agreement after conference. b Recommended for tobacco. All other analyses chosen for cotton.
Table 11-Fertilizer CENTRAL STATES 2-6-2 1-5-4 2-4-4 2-5-3 3-4-3 1-7-2 1-6-3 1-3-6 5-3-2a
...
... ...
. ...
Considering next the series of analyses selected at the more recent conferences in some of which fertilizer ratios were
Table 111-Possible Fertilizer Ratios by Use of Trianglea N-p20s N-KgO KzO-PzOs --N-P~O~-KzO1-9-o 1-0-9 l-l-s 2-2-6 3-4-3 5-2-3 3-5-2 5-3-2 1-2-7 2-3-5 0-2-8 2-0-8 2-8-0 3-6-1 5-4-1 1-3-6 2-4-4 0-3-7 3-0-7 3-7-0 2-5-3 4-1-5 6-1-3 0-4-6 1-4-5 4-0-6 4-6-0 4-2-4 6-2-2 0-5-5 1-5-4 2-6-2 5-0-5 5-5-0 4-3-3 6-3-1 1-6-3 2-7-1 0-6-4 6-0-4 6-44 7-1-2 4-4-2 7-3-0 1-7-2 3-1-6 0-7-3 7-0-3 4-5-1 7-2-1 1-8-1 3-2-5 0-8-2 8-24 8-0-2 5-1-4 8-1-1 2-1-7 3-3-4 0-9-1 9-0-1 9-1-0 a It will be noted that these ratios are stated in numbers that total 10.
It is of interest to consider the location on the triangle of the high-analysis materials now being offered for sale by the synthetic nitrogen industries. Of these there are four forms of Nitrophoska, two of Ammo-Phos, Diammonphos, potassium-ammonium nitrate and nitrate of potash. The locations of these materials by the triangle scheme is shown in Figure 10. It is likely that more of such materials will be produced in the near future. If they are to be used as materials, no change in analysis need be given consideration, but if they are to be offered directly to the consumer as they stand, then consideration may well be given to making them conform to the triangle scheme.
* Schreiner, Botan. Gae., 60, l(1910).
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Figure 11-Tennessee Figure 12-Louisiana Figure 13-Texas Fertilizer R a t i o s Adopted w i t h o u t Use of Triangle h i n c i p l e at R e c e n t S t a t e Conferences
In Figures 11, 12, and 13 are given the locations of the fertilizer ratios adopted in recent conferences called by the states of Tennessee, Louisiana, and Texas, respectively. definite They also indicate the desirability of having a scheme of selecting these ratios such as is permitted by use of the principle suggested. The triangle scheme has merit. There may be objections to it that may make it necessary to set the scheme aside. The chief reason for presenting the subject a t this time is to call forth all of the possible objections to it in order to determine to what extent these objections are well founded
or what modification could be made to the scheme to overcome them. T a b l e IV-Fertilizer
TEXAS 2-4-2 2-6-2 3-10-3 4-10-7 0-5-2 34-5 2-10-2 2-6-o
2-4-3 2-5-1 0-6-2 6-10-7 1-6-1 3-10-8 3-8-3 2-8-2
..
Ratios Adopted by Individual Statesa LOUISIANA TENNESSEE 2-4-2 2-4-3 2-4-2 2-4-3 2-6-2 2-5-1 2-6-2 2-5-2 3-10-3 0-6-2 3-10-3 0-6-2 4-10-7 6-10-7 4-1&6 4-11-5 0-5-2 4-6-2 1-4-5 1-6-1 3-8-10 3-10-5 3-8-6 3-9-4 ... 5-10-3 3-3-3 2-9-5
5-5-0
. ..
...
...
...
4-6-2 . 0-7-5 . .. ... Arranged in such manner as to show the similarity of the lists.
I.
Computation of No-Filler Fertilizer Mixtures’ A. B. Beaumont and Harold R. Knudsen DEPARTMENT OF AGRONOMY, MASS.4CHUSETTS AGRICULTURAL COLLEGE, AMHERST, MASS.
ITH the development of high-analysis mixed fertilizers has come an increase in no-filler mixtures. The recent rapid increase in the number of concentrated fertilizer materials has made possible the compounding of grades of complete fertilizers double and triple the strength standard five years ago. These materials, together with a wider range of low- and medium-analysis organic and inorganic materials, make it easy to select the proper ingredients for no-filler mixtures of almost any desired grade. The purposes of this paper are to show how certain types of no-filler formulas for complete fertilizers may be computed and to indicate the possibilities and limitations of mixtures from different carriers. Either of the triangular systems proposed for calculation of ternary fertilizer mixtures is useful in ascertaining the ratios possible from any lot of materials. Merz and Ross2 have proposed the equilateral triangle, and Colbjornsen3 has shown how the right isosceles triangle may be used for the same purpose with great facility. These authors, however, do not discuss the computation of no-filler mixtures. Figures 1 and 2 illustrate the use of the equilateral and right isosceles triangles in the determination of ratios. The vertices A , B, and C represent materials carrying nitrogen (N), phosphoric acid (P,Ob), and potash (&O), respectively. The designation 100 per cent simply meavs that all the plant food carried, or considered, in any particular material is of one 1 Presented by A. B. Beaumont as a part of the Symposium on “Concentrated Fertilizers and Fertilizer Materials” before the Division of Fertilizer Chemistry at the 76th Meeting of the American Chemical Society, Swampscott, Mass., September 10 to 14, 1928. 2 Merz and Ross, U. S. Dept. Agr., Bull. 1280 (1924). * Colbj6rnsen, IND.ENG.CHEM..18, 724 (1926).
kind only-e. g., nitrogen in sodium nitrate, phosphoric acid in superphosphate, or potash in muriate of potash. Materials containing two nutrients-e. g., ammonium phosphateare represented on the sides of triangles and materials or mixtures containing three nutrients by points within the triangle-e. g., a 4-10-6 or any other grade built on a 2:5:3 ratio is represented by the point G. Note-As used in this paper the figures of a fertilizer grade represent percentage of nitrogen (N), phosphoric acid (PsOI), and potash (KzO),respectively. Also, following trade practice, dashes are used in grade designations, and should not be confused with minus signs.
No-filler mixing problems may be solved by using simultaneous algebraic equations wholly or partially. Following is a presentation of types of problems and suggested methods of solution. Type 1, the simplest, may be solved by simple arithmetical computation as readily as by algebra. With other types arithmetical solutions must be by trial and error and therefore very tedious. Type 1-Mixtures
Composed of Three Single-Element Components
By single-element components are meant such materials as sodium nitrate, superphosphate (acid phosphate), and muriate of potash. From such carriers a mixture of any ratio of nitrogen (N), phosphoric acid (PZOS), and potash (K,O) is possible. Any grade, up to a certain maximum, can be built on any ratio, with filler, but there is only one no-filler grade possible for any ratio, and this may or may not be integral. The maximum grade, in this case, is the no-filler grade. Question. What no-filler grade may be mixed on the 2: 5: 3 ratio, using ammonium sulfate (20.5 per cent N),acid phos-
