804
THE JOURNAL OF INDUSTRIAL A N D ENGINEERING CHEMISTRY.
Dec., 1909
POTASH TESTS IN COMMERCIAL FERTILIZERS.
Excess of chlorides lessens this loss as in experiment No. 9, due, I believe, to hydrochloric acid BY J. E. BRECKENRIDOP. formed by the action of the phosphoric acid in the Received August 29, 1909. . acid phosphate on the muriate. Any insoluble The fact that potash tests’ in fertilizers as carried compounds which might form by the action of the out by the methods of the Association of Official soluble potash on the insoluble material in the Agricultural Chemists are low seems to have been rock, especially the silicates of iron, alumina and lime, would a t once be dissolved by the. hydrowell established. To determine where this loss occurs and what chloric acid formed and having- ammonium chloconditions effect this loss, in 1906 I made the fol- ride in the solution, when the ammonia and ammonium oxalate are added, the occlusion of potash lowing experiments: Theory. Results by would be somewhat prevented. Per official Loss. cent. method. Per Exp. Further investigation led to the following- experiKsO. Percent. cent. NO. rnents in 1908 and 1909: 1 Fresh acid phosphate and muriate of potash. .......................... 6 23 6.06 0.17 Experiments with hnown amounts of acid phos2 Fresh add phosphate and high-grade 5.98 0.30 phate and muriate of potesh, allowing the solutiolz sulfate of potash.. ................ 6.28 3 Fresh add phdsphate and double as made by the official method, and having had the manure salt.. ..................... 7.09 6.79 0.30 ammonia and ammonium oxalate, to stand different 4 Fresh acid phosphate and 30 per cent. 8.48 8.31 0.17 times belore filtering: salt .........! .................... 5 Fresh acid phosphate and 20 per cent. Weighed into a 500 cc. flask g grams of acid 10.19 10.00 0.19 salt .............................. 6 Fresh add phosphate and muriate of phosphate, testing water-soluble potash 0 . 0 2 per 6.23 6.07 0.16 potash and 7 per cent. ,CaCOa cent., and I gram muriate of potash, testingwater7 Fresh acid phosphate and muriate of potash and 7 per cent. CaCOs and 6.5 soluble potash 51.70 per cent. Proceeded as in 6.23 5.84 0.39 per cent. sulfate of iron.. ........... official method, allowing solution, having had the 8 Fresh acid phosphate and muriate of potash and 7 per cent. CaCOz and 6.5 ammonia and ammonium oxalate, to stand before per cent. iron and aluminum phosfiltering- : 6.23 5.90 0.33 phate rock.. ...................... 9 Fresh and phosphate and muriate of potash and 6.5 per cent. CaCOa and 6 5 per cent. sulfate of iron and 6.5 per cent. NaCI.. 10 Fresh acid phosphate and 30 per cent salt and CaCO;, and 6.5 per cent. sulfate of iron..
.............
.....................
...
6.23
8.46
6.11
7.81
0.12
0.59
The materials used in experiments Nos. I , 2r 3,f4 and 5 were weighed into flasks, water added and the whole boiled for one hour, then proceeded a s in official method. The materials used in experiments Nos. 6, 7 , 8, and 9 were weighed into flasks and water’added to a paste and heated to 2 1 2 O F. for 2 0 hours, then proceeded as in official method. The materials used in experiment No. I O were weighed into flask and water added to a paste and allowed to stand longer than experiments Nos. 6, 7, 8 and 9-about three days on top of a steam bath-then analyzed by official method. Remarks.-Potash salts having no chlorine, as high-grade sulfate of potash and double manure salt, give greater loss than muriate of potash, 2 0 per cent. and 30 per cent. salts. Compounds of iron and aluminum and lime have the greatest effect in giving low potash results. 1
Read at meeting of American Chemical Society, Detrolt. 1909.
Result. Per cent. K20. 4.84 4.94 5.06
......... .........
2 hours. 24 hours. 72 hours..
Theory. Fer cent. 5.19
.......
..
..
LOSS.
Per cent. 0.35 0.25 0.13
Mr. M. H. Pingree, in a paper before this Society a t Baltimore, in 1908, found that in allowing the solution to stand two weeks before filtering, the theoretical amount of potash would be found. His results were : “Sample of acid phosphate and sulfate of potash, analyzed by official method, allowing solution having had the ammonia and ammonium oxalate to stand. Per cent. K20.
Ordinary time gave as a result. ..... 5 .04 1 week.. 5.39 2 weeks., 5.41
......................... .........................
Theory. Loss.
Per cent. 5.45
.. ..
Per cent. 0.41 0.06 0.04
Sample, sulfate of potash, fish, acid phosphate and blood gave by official method: Per cent. Standing ordinary time.. 1 week.. 2 weeks
...........
......................... ..........................
K~O.
5.31 5.48 5.62
Theory. Per cent. 5.62
..
..
Loss. Per cent. 0.31 0.14 None
There seems to be a secondary reaction, by which the lost potash goes into solution on long standing in Dresence of ammonia.
BRECKENRIDGE ON POTASH T E S T S I N COMMERCIAL F E R T I L I Z E R S . The weight of sample was reduced to 5 grams in a 500 cc. flask and the official method was followed, allowing solution to stand two hours before filtering. Result: 4.89 per cent. K,O on theory of 5.19 per cent. Loss, 0.30 per cent.
.
The following method was tried, which we shall call B , using 5 grams for weight: Method B.-Placed sample of fertilizer on a 1 1 cm. filter paper and washed with small portions of cold water into a 500 cc. flask if 5 grams were amount of sample taken, and into a 2 0 0 cc. flask if z grams were taken, until the flask is about four-fifths full. Added to washings in the flask 5 cc. hydrochloric acid (concentrated), heated to boiling, made alkaline with ammonia, added ammonium oxalate, cooled a t once and filtered and proceeded as in official method. Result: 5.06 per cent. K,O on a theory of 5.19per cent., making loss of 0 . I 3 per cent. Remarks.-We shall notice that washing the sample on filter reduces our loss to 0.13 per cent. K,O on a theory of 5.19per cent., while the official method gave us a loss of 0 . 3 5 per cent. To find whether the materials insoluble in acid, as we find them in phosphate of rock, cause this loss, or whether the precipitation by ammonia and ammonium oxalate in the absence of these insoluble materials causes the loss, or both, the following experiments were made : Experiments with Water Solution of Acid Phosphate and Water Solution o# Muriate of Potash, with and without Carbonute of Lime and Hydrate of Lime.-Solution No. I : 20 grams acid phosphate in 300 cc. of water, heated and filtered into a 500 cc. flask and residue washed to 500 cc. Solution No. 2 : 4 grams muriate of potash in 2 0 0 cc. flask, dissolved in water and made to mark.
Theory. Percent. KoO. Result. 5 Added 5 0 cc. of solution No. 1 and 10 cc. of solution No. 2 in 200 cc. flask, added ammonia in excess, then hydrochloric acid to slight acidity to clear the solution, heated, added ammonium oxalate, cooled and proceeded as in official method. The filtrate showed no further precipitate with ammonia, showing a good , ,, 5.09 separation of lime
npx. NO.
.. . . .
. . .. . . . .. . . . .
..
LOSS.
Result.
Per cent.
Gain. Per cent,
5.11
0.08
..
..
5.16
0.03
..
..
5.20
..
0.01
..
5.20
..
0.01
Per cent.
Gain Per cent.
0.10
,.
0.15
..
6 Added 5 0 cc. of solution No. 1 in 200 cc. flask, added dry CSCOS
to neutralize. if possible, the acidity. The acidity was not destroyed b y exceSs so Ca(OH)* was added until solution was alkaline, then 10 cc. of solution No 2 were added, and proceeded , as in official method.. .
. . .. . ..
..
5.04
This was to see if calciuni phosphate precipitated would occlude any potash when the insoluble material of the acid phosphate was absent. Remarks.-There seems to be some loss when the insoluble material of the acid phosphate is absent. Addition of hydrochloric acid or citric acid, as in experiments Nos. 3 and 4, seems to overcome this loss.
Experiments to Show the EfJect of Magnesium Salts, Iron and Lime Salts when Present in Solutions of Acid Phosphate and Potash, the Insoluble Material of the Acid Phosphate being A bsent.-Solution No. I: Water solution of acid phosphate 40 grams to 500 cc. of water, Solution No. 2 : Water solution of muriate of potash 8 grams to zoo cc -~
LOSS
Exp. NO.
Theory.
Per'
Result.
K20. cent.
5.12
0.07
5.07
0.12
5.01
0.18
1 Added 5 0 cc. of solution No. 1 and 0.5 gram Ca(OH)z and 10 cc. of solution No. 2 and 0.25 gram MgSO, in 200 cc. flask and proceeded as in official method.. 2 Same as No. 1 only used MnClz instead of MgSO,. 3 Same as No. 1 and No. 2 only used sulfate of iron instead of magnesium salts. . ,
. . . . . ... . . 5 . 1 9 . . .. .. . ..... .. .. . . .. . . . . ... . . . . .. . . . I
Theory. Per ceut NO. Ks0. 1 Added 50 cc. of solution No. 1 and 10 cc. of solution No. 2 in 200 cc. flask and proceeded as in 5.19 official method.. 2 Added 5 0 cc. of solution No. 1 and 10 cc. of solution No. 2 and 0.05 gram CaCOs in 200 cc. flask and proceeded as in official method 3 Added 5 0 cc. of solution No. 1 and 10 cc. of solution No. 2 and 0.05 gram CaCOr and 0 . 6 gram citric acid in 200 cc. flask and proceeded as in official method.. 4 Added 50 cc. of solution No. 1 and 10 cc. of solution No. 2 and 0.05 gram CaC03 and 2 cc. hydrochloric acid in 200 cc. flask and proceeded as in official method
Exp.
Loss.
Remrks.-IIron seems to have a little effect on losing potash in these tests, magnesium salts not so much as iron. Inasmuch as the insoluble in acid in phosphate rock becomes the insoluble in water, to a large extent, in acid phosphate, the following experiments, with different grades of phosphate rock and muriate of potash solution, were made to find the effect on losing potash when the official method is used: These experiments were made by adding the materials together in a zoo cc. flask and Proceeding as by official method f o r potash.
806
T H E JOURNAL OF INDUSTRIAL A N D ENGILLTEERINGCHEiMISTRY.
Results should show evaporating tion 6 . 3 7 per cent. K,O. Experiment .Vo.
25
cc. of solu-
I.
P e r cent. 1 gram muriate of potash. grams of phosphate Insoluble and s a n d . . 9.30 Iron and alumina. . . . . . . . . . . . . . . . 2.45 rock, testing.. Bone phosphate of lime, dry basis. 68.18
......
’
.............
i
Potash determined at once as soon as solution was cold after adding ammonia and ammonium oxalate. LOSS.
................ .
About 2 hours’ standing After 24 hours’ standing before filtering.
Ex$erimenf No.
Result. 6.23 6.15
P e r cent. K20.
0.14 0.22
2.
P e r cent. 1 gram muriate of potash.
.......
.............. .............. Bone phosphate of lime. dry basis.
11 .20 2.40 65.94
LOSS.
Potash determined a t once After 48 hours’ standing..
........... ..............
6.15 6.10
Per cent. 0.22 0.27
Experiment No. 3. Per cent. 1 gram of muriate of potash. 5 grams of Tennessee Insoluble and sand .............. 5 63 phosphate rock, test- Iron and alumina.. 6.20 ing.. Bone phosphate of lime, dry basis. 74 19
..............
{
..............
LOSS.
........... ................
Potash determined a t once.. After 48 hours’ standing
6.10 6.03
P e r cent. 0 27 0.34
Experiment No. 4 . Per cent. 1 gram of muriate of potash.
of rock, testing
li‘
................ ............................. .......................... ..................
nsoluble and sand.. Iron. Alumina. Phosphoric acid..
5 12 21
Such being the conditions there seems to be great chance for rendering water-soluble potash insoluble when we add water to our samples and boil a s in official method. Washing away as soon as possible the soluble material from the insoluble material of fertilizers seems b u t a reasonable way of overcoming somewhat this possibility of losing potash in our methods. Comparing official method with method B a s given before, we have : Sample No. r.-Acid phosphate having about 5 per cent. iron and aluminum oxides. Sample No. 2.-Muriate of potash testing 51.70 per cent. K,O. Result. Percent. Exp. No. KzO. 1 Weighed into 500 cc. flask 9 grams sample No. 1 and 1 gram sample No. 2 and analyzed by official method. . . . . . . . . . . . 4.70 2 Weighed 4.5 grams of sample No. 1 and 0.5 gram sample KO.2 on to filter paper and analyzed by method B . . . . . . . . . . . . . . . . 5.03
Loss, Per cent.
0.47
0.14
Sample of 7 per cent. potash goods, representing about 600 tons, gave by official method 6 . 7 0 and 6 . 7 2 per cent. K,O, by method B, 7 . I O per cent. &O. For samples having large amounts of organic matter hot water should. be used for washingin method B in place of cold water. LABORATORY OF AXERICANAGRICULTURAL CHEMICALCOMPANY, CARTERET, N E W
JERSEY.
45
LOSS.
Percent. Percent. 5.91 0.46 5.92 0.45
............ ................
Potash determined a t once.. After 48 hours’ standing
Dec., 1909
ADDRESSES. THE DYNAMIC VIEWPOINT O F SOILS.’
CONCLUSIONS.
T h a t as the insoluble in acid in phosphate rock increases, the loss in potash increases. Phosphate rock having moderate amount of insoluble material and high iron and alumina as in experiment No. 3 has decided effect in losing potash. Large amounts of iron and alumina with even moderate amounts of insoluble, a s in experiment No. 4, where we have about 1 2 per cent. iron, 21 per cent, alumina, 5 per cent. insoluble material, have the most effect on losing potash. 1s it not reasonable to believe t h a t what has caused this loss is similar to that which takes place in potash solutions in contact with soils, when the potash becomes fixed by the iron, alumina and silica ?
BY FRANK K. CAMERON.
Within the past decade or decade and a half there h a s been a marked revival of interest in soils and soil fertility. This has led to the advancement of a number of theories, most of which have the attractive characteristics of apparent simplicity, i. e., they attribute fertility or lack of fertility t o some one or perhaps two causes. Another remarkable feature of most of these theories is the certainty and sureness of tone with which they are announced. For instance, one of the most brominent of American agronomists stated in a recent letter that “The currently accepted theory is that the principal factor in the loss of fertility is the loss of humus and nitrogen, and the data a t hand seems t o me to leave this theory as yet quite competent t o explain the facts.” And within the past few months we have been Phosphorus is already the element t h a t advised t h a t limits crop yields on those great soil areas in the corn belt, I‘
1 Published b y permission of the Secretary of Agriculture. Abstract of an address prepared for the Division of Food and Agricultural Chemistry a t the Detroit meeting.
