T H E J O U R N A L OF I W D L - S T R I A L A N D ENGIiVEERIiVG C H E M I S T R Y .
30
various kinds of oxidation going on in plants and animals could be duplicated by a detailed study of oxidation in soil. The oxidation in soil Fer se is due mainly to non-enzymotic forces, inorganic and organic, working separately, conjointly, or in reinforcing or activating combination. I n soil oxidation the nature of the organic matters seems to be of great importance. Conjointly with the oxidation in soils which is active whether the soil is planted or ufiplanted is the oxidizing power of the roots. CONCLUSIONS.
Soils have the power to oxidize aloin. 2. This oxidizing power is increased by adding water to optimum moisture, by the commonly used fertilizers in conjunction with plant growth, by salts of manganese, iron, aluminum, calcium, and magnesium, in the presence of simple organic hydroxyacids. 3. Oxidation in soil is comparable to oxidation in plants and animals. 4. The oxidative power of the soil appear to be mainly non-enzymotic, the results of interaction between inorganic constituents and certain types of organic matter. It may be brought about by organic matter in a state of autoxidation and by inorganic oxygen carriers such as manganese and iron. 5 . Oxidation is greater in the soil than in the subsoil. 6. Oxidation is greater in fertile soils than in infertile soils. I.
u. s
BUREAUOF SOILS, DEPARTMENT O F AGRICULTURE, WASHINGTOND. C.
THE USE OF NITRATE OF SODA I N COMMERCIAL FERTILIZERS, B y CHARLESS. CATHCART. Received November 1, 1910.
The value of a commercial fertilizer is measured by its content and form of nitrogen, phosphoric acid and potash. In order to determine this value with any degree of accuracy, it is the practice of the chemists connected with the fertilizer inspections of the several States to ascertain the amount of nitrogen contained in the sample in the form of nitrate, ammonia salts and organic matter. Determinations are made of the total and insoluble phosphoric acid; the difference between the figures thus obtained is the available phosphoric acid, and, in addition to determining the percentage of water soluble potash it is ascertained whether it is to be considered as in the form of muriate or sulphate. From this procedure it is quite evident that sufficient attention is being given t o the form or availability of the valuable constituents of this class of materials with the exception of the organic nitrogen. That there is a very great difference in the character, and, consequently, in the availability of the various organic nitrogeneous materials used in compounding the mixtures is conceded by all interested, but it seems that the chemists, and others, have been contented t o ignore to a certain extent this important question.
Jan., 1911
Studies on the availability of various nitrogen compounds have been conducted by investigators in Europe a n d ' i n this country, and the results show that when the recovery of nitrogen from nitrate of soda, which has the highest precentage of recovery, is considered as. 100,the relative availability of nitrogen as ammonia is about 7 0 , and from dried blood about 6 4 . j . At the present time a pound of nitrogen in the form of the water-soluble compounds, nitrate of soda and ammonia salts, can be purchased for four-fifths of the cost of the same amount of nitrogen when obtained from high-grade organic materials, such as dried blood. On account of this difference in the cost and the higher availability of the water-soluble compounds, i t is to be supposed that it would be to the best interests of the manufacturers to use these compounds, and more particularly the nitrate of soda, in a large percentage of their brands, since the cost of materials would be diminished and the resultant mixtures would produce more immediate, if not greater, returns. I t is needless to state, however, that we are assuming the manufacturers use only high-grade materials. An examination of t h e following tabulation which was prepared from the records of the inspection for 1909 in New Jersey will show that the supposition regarding the use of .' nitrate of soda is not strictly correct.
.......
Total number of b r a n d s examined.. T o t a l number of b r a n d s containing nitrates Per cent. of b r a n d s containing n i t r a t e s . . , Total number of manufacturers. Total number of manufacturers using nitra Per cent. of manufacturers using nitrates.
..
...............
.............. 4 2 . 6
.......................
50.9
If the records of this inspection are more closely studied it will be found that twenty or more manufacturers may be considered as having a local business and that they have nearly sixty brands included in the above, and of this number a t least fifty contain nitrate nitrogen. If these figures were eliminated from the tabulation, the results would, probably, more nearly represent the facts when considered on the basis of tonnage sold, and the percentage of brands containing nitrates as well as the percentage of manufacturers using this material would be considerably reduced. Since these facts are somewhat a t variance with our supposition, some inquiries were made in order to account for the condition and the principal reasons given were: I. There is a loss of nitrogen in mixtures containing nitrate of soda. 11. Nitrate of soda causes the fertilizer to become pasty and thus cause trouble when used in the drill. In order to get some information regarding these two questions, two experiments were outlined: ( I ) to determine the actual loss of nitrogen, and ( 2 ) the mechanical condition. Experivnevtt I . Loss o j Nitroge%.-It is generally admitted that there is a loss of nitrogen in mixtures containing nitrate of soda and acidulated goods, and that the amount of this loss depends largely upon the materials used. I n order to determine the actual
C A T H C A R T ON N I T R A T E OF SODA I N C O M M E R C I A L F E R T I L I Z E R S .
31
By referring to the tabulation it will be noticed that the loss of nitrogen in the first three examinations was not very great and in no case was it a serious consideration, but the results obtained with set E were suspicious. During the entire time of these three periods the atmosphere was very dry and the samples remained in the same condition, practically, as they were mixed, but between the third and fourth examinations, the weather conditions were reversed and the samples absorbed considerable moisture. The content of moisture in the samples as drawn from thk bags was not determined, but these figures were obtained for the samples after they had been prepared for analysis. These results, of course, did not give the true content of moisture in the original samples but they indicated the increase. From these determinations it would seem as if the moisture content a t the time of the third 'examination had increased from one to two and one-half per cent. while the last examination would increase these figures to three and one-half to fourteen per cent. As previously stated, all of the nitrogen determinations were calculated to the original water-basis before tabulating and, consequently, the lower results obtained in the fourth examination can not be attributed to the presence of the higher percentages of moisture, but the loss was undoubtedly due to the conditions after the water had been taken up. I t would be unwise to draw a conclusion from a single experiment, but the results indicate that the TABULATION actual loss of nitrogen would not be of great importance if the materials could be kept dry but that a n 4i Calculated composition T o t a l n i t r o g e n at end of Kitrogen a s * appreciable loss will occur when there is an absorption + + g$ 8a of moisture. & Z 2; 4 % 4tJ ,E p s 32s 3 &%; -uJ Experiment I I . Mechanical Condition.-One of the ou: go b8 &b .="sa u 8 t $) ga s e +a s Z k u 6 2 74" 22 t0 :b p h h important problems in the manufacture of fertilizers A 1 7 4 101 312 416 413 409 413 409 is to prepare mixtures that will remain in a good 2 7 6 1.01 2 77 3 78 3 76 3 76 3 73 3 74 mechanical condition: I t is generally assumed that 3 7 8 1 01 2 43 3 41 3.44 3 43 3 35 3 32 4 7 10 1 01 2 08 3 09 3 05 3 07 3 06 3 01 the presence of nitrate of soda in a mixture will cause B 1 7 4 147 286 433 434 436 432 422 the material to become more or less moist, depending 2 7 6 147 398 252 399 410 396 382 upon the amount of soda present, and thus make the 3 7 8 1.47 2.17 3 64 3 65 3 66 3 63 3 44 fertilizer in a poor condition to be used in drills. 4 7 10 147 1.82 3.29 3 41 3 34 3 24 3 14 I n order to get some data on this question, two C1 7 4 194 260 454 448 453 450 429 2 7 6 1.94 2 25 4 19 4 11 4 21 4 16 4 02 series of mixtures were prepared, one of which was 3 7 8 1 94 1 91 3 85 3 91 3.77 3 81 3 75 the same as used in the previous experiment with the 4 7 10 1 94 1 56 3 46 3 50 3 61 3 43 3 34 addition of one set of samples which contained no D 1 7 4 2 40 2 34 4.74 4 34 4.80 4 70 4 42 nitrate of soda. The second series was the same 2 7 6 2.40 1 99 4 39 4 46 4 38 4 49 4.29 3 7 8 2.40 1.65 4 13 4.05 4 05 4.04 3 83 as the first with the exception that sulphate of potash 4 7 10 2 40 1 30 3.70 3 63 3.76 3.61 3 47 was used instead of the muriate. These mixtures E1 7 4 2.87 2.08 4 95 4 95 4 85 4 84 4 52 were prepared a t the same time as those in loss of 2 7 6 2.87 1 73 4 60 4.57 4.57 4 47 4 24 nitrogen experiment and were, of course, subjected 3 7 8 2.87 1 39 4 26 4.11 4.19 4 31 3 97 4 7 10 ' 2.87 1.04 3.91 3.90 3 81 3.74 3 61 to the same weather conditions. These samples were stored on shelves in a large room and allowed to stand Inasmuch as each set of samples contained the for three and one-half months when they were resame quantity of nitrate of soda, the several sets in moved from the bags and subsampled. The moisture the series have been averaged as follows: content was then determined in each sample. The Calculated Found. results obtained may not indicate the maximum nitrogen. quantity of water absorbed, nor the effect that would Set. Per cent. R u n No. 1. R u n No. 2. R u n No. 3. R u n No. 4. be produced by having a number of bags stored in A 3.61 3.60 3.60 3.56 3.54 B 3.81 3.85 3.87 3.79 Q.66 a pile, but they are comparable because they were C 4.02 3 99 4.03 3.98 3.85 subjected to the same conditions. D 4.22 4.24 4.25 4.21 4.00 E 4.43 4.38 4.36 4.3'4 4.09 The following tabulation will give the calculated
loss of nitrogen in this class of mixtures and, also, t o ascertain whether the loss is immediate or gradual, a series of mixtures was prepared using a constant quantity of acid phosphate with different amounts of nitrate of soda and muriate of potash, high-grade tankage being used as a diluent. These ingredients were purchased from a large fertilizer company and should be fairly representative. The plan of the experiment was to make all of the conditions as nearly the same as found in the regular manufacture as possible. With this in view a fivepound sample of each of the formulas was carefully prepared after the composition of the various ingredients had been determined. These mixtures were placed in small bags made of the same kind of material t h a t is used for this purpose by the trade. Two days after the samples had been prepared theywere removed from the bags, and, after a thorough mixing, subsamples were taken and examined for their content of moisture and nitrogen. The original samples were replaced in the bags and carefully stored. This operation was repeated a t the end of two, four and fifteen weeks. The results obtained for nitrogen in each of these examinations were computed to the same water basis as that calculated for the original mixture, and the following tabulation will give these results as well as the calculated content of nitrogen, phosphoric acid and potash.
---
-5
P I -
p: k ---
e
r b .
44
T H E JOl-RiYAL OF I.YD(I;STRIAL An'D E-YGIAYEERIAYGC I i E J I I S T R Y .
32
content of moisture in the various mixtures and the amounts found to be present a t the time of examination. TABULATION. Calculated.
ofi
5
& ,
u
g:,
-
c
P2 2 ,+'Z ;
a
j
1 2 J
4 G 1 2 3 4 H 1 2 3 4 I 1 2 3 4 J 1 2 3 4 K 1 2 3 4
z ....
I .O1 1.01 1.01 1.01 1.47 1.47 1.47 1.47 1 .94 1.94 1 .94 1.94 2.40 2.40 2.40 2.40 2.87 2.87 2.87 2.87
.-o
W
5.2
25s
2€8 pi
;.*- =b .
$ex*>
10
4 6 8 10 4 6 8 10 4 6 8 10
4 6 8 10 4 6 8 10
28
.9 0
g'
'u,
10.57 10.22 9.87 9.51 10.08 9.75 9 42 9.09 9.88 9.54 9.22 8 s9 9.67 9 34 9.01 8.68 9.46 9.14 8.80 8.48 9.26 5.93 S.60 8.27
4 6 8
,
-s; 5..-" 2
z
.
-
m . M
Z?
u
S'C j
4
$2 5;
0
vi d f i
F
u i
....
.... ....
2;
7
Et 33.
E t
e
F
U6.k
--__ ----_
i
9.30 10.10 10.40 13.60 14 ,48
14.90 14 . 9 0 15.80 15.30 16 Y O 17.00 17.95 1s . 2 0 18.05 18.45 18.25 18.25 17.80 17.65 18.45 17 95 17.65 l i ,75 18,15
- 1.27
-0.12 0.53 4.09 4.40 5.15 5.48 6.71 5.42 t 7 36 i.78 9 06 8.53 + S 71 t 9.44 9.57 8 79 8.66 8.85 9.97 8.69 i- 8 . 7 2 9.15 * 9.88
+ + + + + + +
+ +
+ +
+ + + + +
TABULATION.
23
i
€:
P
$
-
4 .
a8 %3 E .g .f:F 8 5; f
a m i
bI
vi&
1 2 3 4
.... .... ....
1
1.01 1.01 1.01 1.01 1.47 1.47 1.47 1.47 1 .94 1 .94 1.94 1,94 2.40 2.40 2.40 2.40 2 si 2.87 2.87 2.8;
2 3 4 s 1 2 3 4 0 1 2 3 4 P I 2 3 4 Q
u
L
F E
u
L
E& 0.bk d d
1
2 3 4
....
4 6 8 10 4 6 8 10 4 6 ?
10 4 6 8 10 4 6 8 10 4 6 8 10
gz
uwk
Calculated e
i
I
0
._ %%&
'g u
o m .
C
xe M
$ $
.-% Z
'5 8
i'
s
10.65 10.34 10.03 9.il 1 0 , 16 9.87 9.5s 9.29 9.96 9.66 9.38 9 .CY 9.75 9.46 9.17 8.88 9.54 9.26 8 96 8 68 9 .34 9.05 8.76 8.4i
L
$
0 U
E,. z0
.
6.48 6.70 6.65 6.90 9.35 9 40 8 60 8 33 10.83 10.35 10.30 10.20 11.75 11.25 10.72 10.65 12.38 11.53 11 33 11 35 14 55 13.98 13.27 13 .OS
-4.17 -3 64 3.38 .- 2 . 8 1 -0.81 0.47 -- 0 . 9 8 -0.96 0.87 0 69 0.92 1.11 2 00 1,iY t . 1 .S5 1.77 2.84 2.27 2.37 2.67 t 5.21 4.93 4.51 - 4 61
~
+ + + + + + + + +
Jan., 1911
The results of these two sets of mixtures would indicate that the sulphate of potash did not absorb much, if any. moisture xhile the muriate did absorb moisture and the quantity of this absorption was greater as the per cent. of potash increased. The moisture content in each set of the tn-o series increased with the amount of soda added but in every case the set prepared with the muriate contained more than the corresponding set prepared. with the sulphate, and, as found with the set containing no nitrate, the quantity was increased with the per cent. of potash. All of the samples in the sulphate series, nTith the exception of set Q , were in a good mechanical condition and those in the muriate set containing 1.47 per cent. nitrate nitrogen and from 6 , to I O per cent. potash were no better than those in the other series which contained 2 . 8 7 per cent. nitrate nitrogen. Judging from these results, it appears that fertilizer mixtures can be prepared so that they contain as much as 2 . j 0 per cent. nitrate nitrogen and I O per cent. potash, stored under severe weather conditions, and will remain in a good mechanical condition, provided the potash is derived from sulphate and not from muriate. According to the reports of the New Jersey inspections about 6 to 8 per cent. of the brands of commercial fertilizers on the market contain potash in the form of sulphate and, consequently, the poor mechanical condition of many of the commercial brands, after they have been stored for a little time, and particularly those containing a high percentage of potash derived from muriate, can be attributed in part to the muriate of potash that has been used in preparing the mixtures. S E W JERSEY .%GRICCI,'CURAL IEM.
EXPERIMENT STATIO6
BRUNSWICK. s.J.
TANKS FOR SOIL INVESTIGATION AT THE FLORIDA AGRICULTURAL EXPERIMENT STATION. By
I\;.BLAIRA K D
s. 13. C O L L I S O S .
Received ,iuEust 15, 1910.
Vhile much light can still be thrown on soil and fertilizer problems by carefully conducted field experiments, there yet remain some problems that can never be solved until we can control and measure the factors more accurately than me can in field
+ + +
By a survey of the preceding table it will be noticed that the mixtures prepared with sulphate of potash and no nitrate of soda a t the time of the examination contained practically the same amount of moisture and the amount found mas considerably lower than the calculated content. The corresponding set prepared with muriate of potash contained different percentages of moisture and the figures increased with the per cent. of potash, but in no instance was the water content as low as in the sulphate set,
TANK5 f O R
SOIL
/,vvrsr/wnow
f i o ~ l o nExPER/M€NT
5TATlON
Sc~kyI"-/'-Q"
Fig.
I
work. T o supplement the field work in orange culture that the Florida Experiment Station is conducting, and to make i t possible t o estimate accurately the loss of solubie fertilizing materials in the drainage
