Oct.,
1911
T H E J O C T R N A L OF I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R 1‘.
dent, Governor J. K. Tener, of Pennsylvania, Secretary Walter L. Fisher, of the Department of the Interior, and others. At 1.00 P.M. the President proceeds to the river front to review marine parade in honor of the Centenary of Opening Navigation on the Ohio River. Parade of miners will proceed from Forbes Field down Fifth Avenue to a reserved reviewing stand on the river front, passing, en route, in review of President Taft and accompanying officials.
______
THE DETERMINATION OF NITROGEN IN COMMERCIAL AMAONIATES OF HIGH NITROGEN CONTENT. Second Report of the Committee on Nitrogen, Division of ?erti izer Chemists, American Chemical Society,
The attention of this committee was recently called to the fact that the determination of nitrogen by the Official Kjeldahl or Gunning method modified for nitrates in commercial nitrate of soda, does not always give concordant results in the hands of different analysts even if the samples in question are presumably identical, as truly representative samples of the same lot of goods. It was thought advisable, therefore, to ask for co-operative work on the analysis of a carefully prepared sample. The SUJ?MARY
OF AN.4LYSES O F N I T R A T E O F S O D A .
Averages only are given. An- Moisture. Nitroeen.
alyst 1
Per cent. Per cent 1.20 15 .50
Official Gunning Method, approximately 3 hrs. digestion after adding potassium sulphate. 2 1.64 15.18 Moisture a t l o o o , 5 gm. 3 h r s . . 2 gm. 12 hrs. Modified Kjeldahl Method. .. 15.30 Modified Gunning Method. 3 1.55 15.60 Official Gunning Method Moisture a t 98-99OC. 4 1 .64 15.79 Moisture a t 1 3 O O C . Used 0 25 gm. and let stand for 5-6 hrs. before heating. 5 1.67 15.33 Modified Kjeldahl Method. 15.22 hIodified Gunning Method. 5 0.69 15.48 Official Kjeldahl Method. 2 gm. salicylic acid, 30 cc. H z S O ~2, gm. Zn dust and Hg. Heated 3 hrs. 1/2 g m . material used. KMnO, added 8t completion of digestion, 15.55 Comb. Kjeldahl-Gunning Method 2 gm. salicylic acid 30 cc. H2S0.,, 2 gm. Z n , H g and K:S04. Heated 2 hrs. 1/2 gm. material used. 2 g m . material used for moisture. Dried 7 hrs. 100-102°, C.in air bath. 1.24 1.5 .09 Official Gunning Method, modified t o include nitrates. 8 1.67 15.25 Official Gunning Method. .Moisture a t 130’ C. 9 2.46 15.48 Stood over night with salicylic acid mixture before digestion. 10 1.98 15.43 Official Gunning Method. 11 0.32’ 14.50‘ Official Kjeldahl Method. 12 1.63 15.41 13 1.40 15.45 Modified Kjeldahl-Gunning hlethod, allowing to stand 1/2 hr. before reduction, and 6 hrs. longer before digestion. 14 15.45 Official Gunning Method. modified to include nitrates. Kept mixture very cold with cons t a n t shaking ior 30 minutes. .. 15.46 1/2 cc. of water added acid mixture and digested without shaking. 15 .. 15.18 1/2 gm. material used and modified Kjeldahl Method. adding 30 cc. acid wvlth 2 gin. salicylic acid dissolved in samr 15.29 1/2 gm. material used, adding salicylic acid dry t o nitrates. 15.48 1/4 gm. adding wet mixture, salicyliL acid and sulvhuric acid. 15.62 D r y salicylic acid and mixing wi h nitrates, using 1/4 gm. Mean. 1.56 15.41 Max.. 2.46 15.79 M i n , 0.69 15.09 1 Omitted from average.
..
..
,
..
783
letter of instructions sent with the sam:)!e substantially requested that nitrogen be determind tlitsreon b y the Official Gunning or Kjeldahl m e t h d s modified for nitrates as given in Bulletin 107 of the Ilureau of Chemistry and that moisture be determineti on two gram portions of the sample. The reason €or specifying two gram portions was that the samples sent out had t o be small, as the time available before the summer meeting was limited. For the same reason, the amount of work asked €or was limited so that i t represented but a small addition to the routine work of those laboratories to which samples and requests for work were sent. These included state fertilizer inspection laboratories, commercial laboratories and fertilizer manufacturers’ laboratories. Replies were received from 14 out of 2 2 analysts to whom requests and samples were sent. The results of the work are briefly shown in the preceding table. C O M M E N T S O F T H E ANALYSTS.
There is a tendency to higher results in using gram than when using larger quantities. 4. After quoting illustrations from his own practice in which differences between his laboratory and others range from 0.5 per cent. to 2 . 0 per cent. of nitrogen were developed, this analyst adds: “We find that the more nitrogen the goods contain, the longer the digestion is required to stand before heating. We usually p u t it on in the afternoon and let i t stand all night.” 14. “We cannot seem t o get as high results with 0.5 gram materials as with 0.25 gram, especially so when we add the mixture of salicylic acid dissolved in sulphuric acid.” There is a wide range in the results reported by the various analysts in the results on moisture as well as on nitrogen. This variation does not seem to depend on ariy one particular factor. The details as reported vary widely as shown in the table and no definite conclusions can be formed from this preliminary work. Local conditions of manipulation and reagents are probably responsible for as much variation as any other factor. The committee recommends that the study of this subject be continued with a view towards the establishment of a standard sample in sufficient quantity to serve the needs of the members in this division or a t least of those members who are particularly interested in this subject. Respectfully submitted, Committee on Nitrogen, C. H. J O N E S , F. C. ATKINSON, I.
0.2
j
F. L. PARKER, JR., PAULRUDNICK, Chairman.
-----REPORT OF THE COMMITTEE ON PHOSPHATE ROCK. J U N E M E E T I X G , A. C. S., 1911.
The committee appointed as the Committee on Phosphate Rock, for the better handling of the prob-
784
T H E J O U R N A L OF I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y .
lems involved, was divided into three sub-committees on Moisture, Phosphoric Acid and Iron and Alumina, respectively. Each respective sub-committee drafted tentative methods and secured some results during the latter part of last year. Profiting b y these results the methods were revised and during the month of April last, these revised methods together with carefully prepared uniform samples were sent out by the committee as a whole for cooperative work. Fifty commercial and consulting chemists were invited to cooperate, and of these, thirty-five signified their desire to assist in the work. Up to the time when this report was compiled results had been received from twenty different analysts. I t has been deemed advisable to reject certain results due to their too wide variation from the average and inasmuch as this report is t o be considered merely as one of progress, we shall refer to the different analysts by number instead of by name. The following are the reports of the different subcommittees: R E P O R T O F T H E SUB-COMMITTEE O N M O I S T U R E .
The Sub-committee on Moisture sent out four separate methods for the cooperative work on the work on the determination of moisture. The results reported are shown on the accompanying Table A. In Method I the determinations were made a t the temperature of boiling water, determination A being dried to constant weight, B for five hours. I n Method I1 the determinations were made a t a temperature of 105O C., determination A being dried t o constant weight, B for four hours. I n Method I11 the determinations were made in a vacuum oven with not more than 50 mm. of pressure and a t a temperature of 60' C., determination -4 being dried to constant weight, B for one hour. I n Method IV the determinations were made in an oven ranging between I O O and 105' for five hours. The variations in the results do not seem excessive for commercial work but the low moisture content makes the percentage variation quite high. The conclusions of the sub-committee are to the effect that it has not been found practical t o do satisfactory cooperative work on the sample. The moisture content of commercial phosphate rock is so low that it is not considered advisable t o attempt to work out and recommend any special method for its determination. Methods devised for similar materials of higher moisture content will undoubtedly prove satisfactory or a t least adaptable to phosphate rock. Inasmuch as the variations between the averages of different analysts were fully as great in any one method as the variations of the same analyst by different methods, there seemed to be no advantage in attempting to average or otherwise summarize the results of this table. R E P O R T O F T H E SUB-COMMITTEE O N
PHOSPHORIC ACID.
The methods formulated by the Sub-committee on Phosphoric Acid included three methods of solution. namely digestion with ( I ) nitro-hydrochloric acid, ( 2 ) nitro-hydrochloric acid with sulphuric acid, and (3)
Oct., 1 9 1 1
hydrochloric acid alone. The method of precipitation was substantially that given in the official methods of the A. 0. -4. C. as given in Bulletin 107, Bureau of Chemistry, p. 3, with two variations, (A) in which the precipitation of the ammonium magnesium phosphate was made a t room temperature and allowed to stand over night, and (B) in which the precipitation was made in ice-cold solution and allowed to stand a t a low temperature for two hours. The results received in time to be embodied in this report are shown in the accompanying Table B. The average results of individual analysts show no material differences in the effectiveness of the three methods of solution tried, except that Method 3, in which hydrochloric acid alone was used for solution, apparently tends towards lower results than the other two methods. We believe that the most satisfactory way to test the efficiency of any method of solution is t o determine the phosphoric acid left undissolved. Since the residue from j grams or more of rock can be used for this purpose, the small quantity of phosphoric acid remaining makes it possible to determine much smaller difference than by analyzing the solution made from the rock. The two different methods of precipitation do not show any definite tendency in one direction or another. Special attention is called, however, t o the excellent results obtained by Analyst 3, following the method regularly used in his laboratory, i. e . , precipitation of the phosphomolybdate in nearly boiling solution and speedy filtration of bot,h phosphomolybdate and magnesium ammonium phosphate. The method commends itself for technical work on account of its rapidity and deserves further trial. The work of Analyst I O using the volumetric molybdate method, precipitating cold, also deserves special attention. His results differ from the other volumetric results in being lower and nearer the average obtained by the gravimetric method. In the hands of Analyst I O a t least, this modification of the Pemberton method gives apparently more satisfactory results than the original Pemberton method as shown in the results of Analyst 13, and is apparently excellently adapted for routine factory control work where rapidity is a t least as important as extreme accuracy, if not more so. When the averages of all the results included in the tabulation are considered, the difference between the different methods of solution and of precipitation almost disappear and the results become, for all practical purposes, almost identical. This points strongly to the conclusion that the variations between individual analysts are due largely to differences in technique and in familiarity with the methods in question. The suitability of the three solutions for the determination of phosphoric acid must be conridered by itself. Although the averages are in good agreement it appears that there is a wider range in individual results from the solution obtained by Method 2 , aqua regia and sulphuric acid, than secured with solutions prepared by the other two methods. Method I ,
T H E J O U R N A L O F Ii\-DL7STRIz4L .4ND E S G I N E E R I N G C H E M I S T R Y .
Oct., 1911
Method 1. _--A__-
A. Analyst. Const. wt.
B 5 hrs.
_--_
78.5
TABLEA.-DETERMINATIONOF MOISTURE. Method 3.
Method 2.
A
Const. Nt.
A.
B. 4 hrs.
Const. wt.
Method 4.
B. 1
hr.
r
5 hrs.
-
Const. wt.
Miscellaneous methods. b 7 -
4 hrs.
2A..
0.50 0.49 5 hrs. 0.50 0.48
.
0.50. 0.54
4 hrs. 0.61 5 hrs 0.57
2B
0.31 0.29 0.65
3...... 4 . .. . . . 5.
Const. wt. 0.51 0.50
0.67
0.65
0.66
0.61 0.53
0.66 0.59 0.61
.....
0.63
0.54
6...... 8......
0.65)
0.71 9..
....
0.iZ 0.75 0.74
0.73 0.67
0.70
1
0.70.
1
0.69 0.67)
10..
....
0.64~
0.71
0.25 0.25 0.24
11... . . . 12. . . . . .
0.65
0.3R
0.34
1
i1
0.30 0.35
0.40
0.45 0.45
0.61
0.780
0.75
0.36
0.46 0.43
0.34 0.50 0.38
15... . . . 17..
....
18..
....
0.50n 0.620
1
0.65 0.67 0.66 0.65)
I' q
20...... 21 . . . . . .
0.56) 0.49 0.52
lt
0.45~ 0.44
0.52
0.52
o.5jy
0 .59J
0.50 0.55
1
I"
b Method used conforms t o Methods 2 and 4 , except t h a t no vacuum was used. Re]. humidity about 50 per cent. or over. 5 grams used. s t a n t rveieht obtained in 3 hours. Dried on Tvatch glasses to constant weight. Dried in 2 oz. tin boxes t o constant weight. Dried 5 hours in air b a t h heated by incandescent lamps t o 103' c. Dried 1 hour a t 108' C. Dried 1 hour a t 103' C. Dried 5 hours a t 102-10i0 C. Dried 11/* hours a t 101-107° C. Dried 1 hour a t 102-104' C. Dried t o constant weight on watch glasses in air b a t h heated b y incandescent lamps t o 100' C Constant weight reached in 4 hours. Constant weight in 31ir4 hours. Water-bath and cooled in air. 1000 c. Constant weight in 3 hours. Constant weight in 5 hours. Constant weight in 4 hours Temperature of water-bath 98 5 Constant weight in 4 hours. Temperature of steam b a t h 96O. Dried 5 hours in steam b a t h a t 96'. Constant weight in 3 hours. Dried 4 hours. Dried 5 hours a t 100-105~C. Constant a t end of first hour.
'.
con-
T H E J O U R N A L OF I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y .
Oct., s g I ~
TABLE B.-DBTBRXINATION OF PHOSPHORIC ACID. Sol. 1.
Sol. 2.
Sol. 3. 7-d-
Analyst.
1.. 2A 2B
. . ........
........... ...........
3............
4............ 5...
. .. . . . . . .
6............ ?............
B. 30.60 30.351
A. 30.33 3 0 . 0818
29.79 29.79 29.67 29.57 29.90 29.95
30.23 29.98 30.04 30 .OS 30.40 30.36 30.32 30.39
I
l8
29.19l8
30.35
29.57 29.57 29.06
29.86 30.18 29.68 29.81 29.79
30.00 30.18 30.13
30.36 30.33 30.33 30.60 30.57 30.52 30.36
30.27 30.58
10 . . . . . . . . . . . . 2 9 . 9 8 30.18 30.18 30.23
29.80 29.80 29.88 30.13
g............
11.. .
12
.. . ... . ..
............
29.95 30.16 30.13 30.23 30.18
B. 29.75 29.931
29.81
29.87 30.00 30.02 30.14 30 .OO
8............
A. 30.16 30.19’
29.44 29.96
30.35 30.04 29.85 29.94 29.80
B. 29.96 30.071
Miscellaneous methods
30.31
;::3
29 , 3018 29.39 30.31
29.82 29.93
30.29 30.12 30.12 30.17 30.33 30.27 30.24 30.56
29.87 29.89 29.96 30.52 30.48 30.45 30.60
27.71 29.85 29.80 29.96 29.94 29.92 30.33 30.33 30.33 30.36
30.26 30.04 29.46 29.42 29.60 29.48 J 29.80 29.80 29.80 30.13
30.35 30.29 30.30 30.26 30.28
A. 30.13 30.491 2 9 . 2 0 ’\ 29.30
1 18
1
30.03 30.05 3 0 . 273
30.20 29.86 29 85 29.77 30.30 30.24 30.18 30.38
29.84 29,74 29.71 30.60 30.56 30.51 30.36
30.21 30.15 29.60 29.84 29.96
.30.66 30.63 29.36 29.96 29.94
29.90 29.93 29.93 29.95 29.95 30.00 30.04 30.06 30.08 30.18 30.26 30.28
30.23
30.42
29.72 29.72 29.72 29.75 29.75 29.75 29.77 29.77 29.77 29.93 30 .OO 30.10 30.16 30.18 30.18 30.18 30.23 30.26 30.23
30.08 29.98 29.95
29.77 29,82 29,90
29.72 29.94 29.82
3 0 .4918 3 0 . 5OZ0 3 0 . SOz1
30.22 30.24 30.24 30.241
30.34 30.18
30.161 30.19 30.19 30.19 30.21 1 30.23)
l, e ~
30.21 30.24 30.28
30.35 30.27)
..
13..........
30.28
30,301’
15
............
.. ... .. 16B.. , . . . . . . . . 1 6 A . . ..
.......... ............
17.. 18 19 . . . . . . . . . . . .
20
............
29.79 30.32 30.28 30.43 30.34
30.26 30.46 30.36 30.12 30.23
29.89 3 0 . SO 30.54 30.31 30.39
30.16 30.il 30.67 30.18 30.29
29.98 30.52 30.66
30.05 29.95
30.06 29.98 29.96
30.15 29.85
30.17 29.76 29,78
30.09 29.94
30.15 30.00 30.05 29.87
30.05 29.49 30.18 29.72
29.85 29.90 30.02 29.87
29.74 29.60 29.92 29.98
30.14 30.56 29.78
30.15 30.69 29.77
30.11 30.59 29.80
30.12 30.72 29.75
30,507
30.10 29.85 29.56 29.54 29.95 29.60 29,72 30.10 S u m m a r y of the averages of individual analysts. Mean.. . . . . . 30.09 30.17 30.56 Maximum. . . . 3 0 . 3 9 Minimum.. . . 29.79 29.77
.
.
.. ..
30.22
23.85 30.69 30.75 30.18 30.27 30.12 30.10 29.96 29.86
30,03 30.03
30.30 30.72 30.02
30.24 30.27
18
Oct., 1911
T H E J O U R N A L OF I N D U S T R I A L A N D E.\'GINEERING
CHEMISTRY.
787
Washed with distilled water instead of ammonium nitrate solution. "After measuring out a n d neutralizing the solution, i t is brought to boil, Solution S o . 1 used, and method differs only from Method A a s follows: then removed from the fire and precipitated with molybdic solution, and allowed to stand for 15 minutes before filtering. After precipitating with the molybdic mixture the precipitate is allowed t o stand 2 hours before filtering." 3 Method of solution not stated. K e p t in the cold over night instead of for 2 hours. .I Solution in HCI a n d H N 0 3 . Original Pemberton (neutral molybdate) method. Aliquots from same solution. Solution in H N 0 3 . Otherwise same a s (4). Omitted from average. 6 Same solution a s in ( d ) , b u t using molybdate solution over one year old. 7 Determined b y the standard volumetric method. Volumetric. Cold Dptn. Sol. 1. DWeighing yellow p p t n . Cold pptn. Sol. 1 . Factor 0.0376. l o Vol. Cold p p t n . Sol. 2 . l1 Weighing yellow p p t n . Cold pptn. Sol. 2. l2 Vol. Cold pptn. Sol. 3. l 3 Bull. 107, Bureau of Chemistry. Official method, molybdate digested 30 minutes, hfg ppt. filtered after 2 hours. l 5 Same as ( l * ) , b u t Afg ppt. stood over night. Gravimetric method from solution in HCI and "03. l 7 Gravimetric from solution in HN03. l 8 Omitted from average. I Q Sol. 2. 'I'wo hours a t room temperature 20 Sol. 2. Volumetric. z1 Sol. 1 . Volumetric. 2
.
aqua regia alone seems t o have a slight advantage over Method 3, hydrochloric acid alone. TTe do not feel justified in trying to estimate the true percentage of phosphoric acid in the sample except to say that i t is somewhat higher than 30 per cent. R E P O R T O F T H E SUB-COMMITTEE O N IRON A N D ALUMINA.
The Sub-committee on Iron and Alumina sent out two methods for the determination of the combined oxides, viz., the acetate method and the glaser alcohol method; two methods for the determination of the oxide of alumina alone, +. , the thiosulphate method and the caustic potash method; and one method for the determination of the oxide of iron b y use of the Jones reductor and permanganate titration. The results reported are shown on .the accompanying Table C. The work which the committee has done seems t o indicate quite clearly that the methods now commonly used, while often, and perhaps generally, giving quite accurate results when carefully executed in accordance with the directions which the committee has given, are nevertheless subject to grave errors, and one is never certain when correct results are obtained. This is especially true of the methods in which the iron and alumina are precipitated and weighed as the phosphate. We have done a great deal of work on these methods in the past three years, results of which may be stated briefly as follows: In order that the ignited phosphates may contain enough phosphoric acid to form the normal phosphate, i t is absolutely necessary that the second precipitation, either in the acetate, glaser, or thiosulphate method, be made in the presence of an excess of phosphoric acid. I t is absolutely necessary to make this second precipitation in order t h a t all lime and magnesia may be removed. I t is impossible to exactly wash out the excess of phosphoric acid, leaving only the normal iron and alumina phosphates. I t is possible, though h a r d > - practicable, to remove b y ignition all excess of phosphoric acid from a precipitate of aluminum phosphate without reducing the normal aluminum phosphate. I t is difficult, and the results are very uncertain a t best, to remove the excess of phosphoric acid from a precipitate of iron phosphate
without reducing, or rather, driving off some of the phosphoric acid from the compound. I t may be t h a t we can finally secure a method of igniting precipitates in 'which the temperature of ignition is closely controlled, so that the ignited precipitate will not be reduced, on the one hand, or contain an excess of phosphoric acid, on the other. In the meantime, however, it is the opinion that any of the methods based on the ignition of the phosphate is subject to the above-mentioned errors and uncertainties. The results submitted this year are about on a par with those obtained last year, and in both instances, it would seem they are better than those obtained in years past. This may possibly be due t o the more careful statement of the methods. I t is evident, however, from the comments of some of the analysts, that these methods are not yet stated in sufficient detail t o prevent the analyst from going astray occasionally. While the results obtained a t this time are, as stated, better than those obtained in previous years, they are far from being satisfactory. A difference of from 0.4-0.6 per cent. on iron and alumina when only about 6 per cent. is present seems too large to be considered satisfactory in a standard method on the results of which large sums of money change hands. If the extreme figures in any of the methods are rejected, the results are considerably better, though still wide. Most of the results on ferric oxide are very satisfactory. The results of two analyses differ quite widely from those of the others and indicate incorrect standards or incomplete reduction respectively. Work is being continued with the view of working out a method which will be free from the sources of error mentioned above. The object is to weigh the iron and alumina as the oxide rather than as the phosphate. One modification of the acetate .and glaser alcohol method has been tried successfully, and the only objection t o i t is that it prolongs unduly the determination. Among other methods which we have studied we find the molybdate method very promising, and have obtained very accurate, though slightly low, results with it.
T H E J O U R N A L OF I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y .
788
Oct., 1 9 1 1
TABLEC.-DETERX?INATION OF IRONAND A L U ~ I I N A
Analyst. I.......
2A..
........
. . . . . . . . . .. .
2B., . , . . . , . . .
...
Acetate. 0.0990 0.1034 0.1170 0.1140 0.1135 0.1135
Results stated as weight of combined phosphates in 1 gram of rock, Glaser alcohol. Thiosulphate. KOH. 0,1008 0.0566 0.0988 0,0520 0.1100 0.0750 0.0531 0,1120 0.0760 0.1068 0.1045 0.0700 0 .os50 0.0745
J...............
,,,
.. . .. . . . ,
I
.. .. . . . .. . . . ,
S...............
..........
g.....
........
lo.......
0.0996
0.1002 0.1002 0,1008
6... . . . . . . . . . . . . 0.1031 0.1028 0.1026 7..
Miscellaneous methods.
0.0258 0.0258 0,0258 0.0273 0.0258 0.0254 0.0208 0.0208
4............... 0.1021 53..
FezOa. 0.0237 0.0237 0.0255
0 .OS94
0.0636
0.017912
0.0662 0,0662
0.0594 0.0628 0.0628
0.0258 0.0258
0.0548
0.0205
0.048.S'* 0.0564 0.0630 0.060O 0.0698 0.0678 0.0714
0.0240 0.0220 0,0240
0,1090 0.1030 0.0982
0 .0954l2
0.0908'*
0 0723 0.0633 0.0610
0.1033 0.1071
0 .O92ZL2 0.0980 0,0990
0.1034 0.0995
0.1020 0.1019 0.1017 0.1012
0.1024 0,1028 0.1036 0.1032
0 0667) 0.0677 0 0682 } l o 0.0704 o.0705 J
0.0988 0.0996 0.0998
0.0980 0.0986 0.0994
0.0638 0 ,0642 0.0651 0,0654 0.0508 0.0516 0.0587
} 1
.
1
11.
..............
IZ...............
13
............. . ,
0 .I010 0.1010 0.1069 0.1076 0,1058
0.1016
.............
16
...............
0.1006 0.1006 0.1012
+
0.0958 0.0956
0.0559 0.0554 0 0557
20.....
. ..... . . ......, ...., . .
Average.. Maximum.. Minimum.,
1 Acetate 2
0.0238 0.0229 0.0232
0.0558
0.1026 0.1041 0.1026
0.1034 0 1038
Fez03 0.0206 0.0206 0.0203 0.0621 0.0627
0.0614 0.0632
0.0543
........
..........
0.0562 0.0564 0.0532
0.1010 0 ,0996 0,1014
17 . . . . . . . . . . . . . . . 18.......
FePO4 AlPO. 0.0894 4 0.0894)
0.0215 0.0215
0.0990 0.0990
14............... 0.1001
15
'
0.1012 0.1020 0.1004 0,1024 0.1024
0.1024 0.1030 0.1004 0,1020
0.1040 0.1135 0.1004
0.1013 0,1096 0.0957
method as practiced in this laboratory. Complete decomposition of rock.
0.0600 0.0610 0.0564 0.0536 0.0556 0 0.0480 0.0432 0.0550 Summary of averages of individual analysts. 0 0640 0.0755 0.0537
0 .Os85 0.0697 0.0531
Probably calculated to mixed oxids.
0.0241 0.0248 0.0246 0.0248)' 0.0214 0.0214
0.0168 0.0168 0,0171 0.0165
0.0234 0,0258 0.0205
Omitted from average.
0.09474
12
Oct., 1911
T H E J O U R N A L OF I N D U S T R I A L A-\‘D
EA’GISEERI.l7G C H E ; Z . l I S T R Y .
789
3 Suggests t h a t no indicator be used when neutralizing j u s t before adding t h e ”&I, SH,HPO, and precipitating agents. a s the solution loses its yellow color as i t approaches the neutral point a n d the slight precipitate appears while still alkaline The indicator 1s apparently necessary 4 Oxalate method. 6 Bichromate method. 8 B e t t e r results b y heating 2 hours on water b a t h instead o f ‘ / 2 h o u r Fourth a n d fifth results omitted from ayerage 7 Using sodium thiosulphate, for first precipitation a n d ammonium hydroxid for second. Precipitates were red 8 Same a s ( ? ) , b u t precipitates were white. 9 Reduced with stannous chlorid. 10 T h e sulphur seemed to separate o u t in making u p the saturated ammonium thiosulphate solution Sulphur dioxide fumes did not seem to netirely &sappear after a n hour’s boiling. There seemed to be some sulphur left as a residue on the filter paper when the alumina \ < a sdissolved back in dilute €5‘21 ” Probably calculated to the oxid. Omitted from average 12 Omitted from the average
For the last two years all of our work has been done on synthetic solutions. As the question immediately t o be answered is not one of solution but of accurate determination of the iron and alumina in solution, it is quite clear that a synthetic solution offers the better solutions for the successful study of the problem. The sub-committee hopes a t an early date to send out methods for general cooperation which will be superior t o those now in use. Among those who cooperated in this work, aside from the members of the committee, were the following : J . E. Breckenridge, American Agricultural Chemical Company, Carteret, New Jersey. Emily Bresee, Wisconsin Agricultural Experiment Station, Madison, Wisconsin. L. S . Bushnell, Armour & Company, Kansas City, Kansas. F. B. Carpenter, Virginia-Carolina Chemical Company, Richmond, Virginia. A. E. Dorr, Armour Fertilizer Works, Baltimore, Maryland. G. E. Fisher, Grasselli Chemical Company, Cleveland, Ohio. W . P. Heath, N. P. P r a t t Laboratory, Atlanta, Georgia. R . Henry, Virginia-Carolina Chemical Company, Richmond, Virginia. N. W.Hill, Armour & Company, Chicago, Illinois. A. C. Johnson, Armour Fertilizer Works, Baltimore, Maryland. McCandless Laboratory, Atlanta, Georgia. W. D. McNally, Armour & Company, National Stock Yards, St. Clair County, Illinois. W. C. Moor, Armour & Company, N. Ft. Worth, Texas. H. C. Moore, Armour Fertilizer Works, Atlanta, Georgia. R. Xeu, Armour Fertilizer Works, Jacksonville, Florida. Parker Laboratory, Charleston, South Carolina. J. R. Powell, Armour Glue Works, Chicago, Illinois. N. P. Pratt Laboratory, Atlanta, Georgia. Paul Rudnick, Armour & Company, Chicago, Illinois. 0. M . Shedd, Kentucky Agricultural Experiment Station, Lexington, Kentucky. Stillwell & Gladding, New York, N . Y . Stillwell Laboratories, New York, K . Y . W. D. Turner, Armour &- Company, Chicago, Illinois. 0. V. T. LTrban, American Agricultural Chemical Company, Carteret, Ken- Jersey.
E. P. Verner, Parker Laborator!-, Charleston, South Carolina. Wiley & Hoffman, Baltimore, Maryland. J. T. Willard, Kansas State ,%gricultural College, Manhattan, Kansas. R . C. Wiley, Iiansas State Agricultural College. Manhattan, Kansas. F. W . Woll, Wisconsin Agricultural Experiment Station, Madison, Wisconsin. Respectfully submitted, COMMITTEEos PHOSPHATE ROCK. 5th-Committee on M o i s t u r e : W . D. RICHARDSON, Chairnian,
H. IC. MCCONNELI.. S. IT’. WILEY. Saib-Covi+iiitteL>o n Phosphoric 24cid: S. TIT, WILEY,Chairniun. A. 11. PETER, H. K . MCCOKKELL. Sub-Comwiittee o n Irovz and illzt+ni+azrmO x i d s : F. P. VEITCH,Chairman, W.D. RICHARDSOX, A. M. P E T E K , c. F. HAGEDORN, Cizuirnla?l.
AMERICAN GAS INSTITUTE.
The sixth annual meeting of the institute will be held in St. Louis, Mo., on Wednesday, Thursday and Friday, October 18-20, 1911. Headquarters will be in the Hotel Jefferson, and the meetings will be in hlemorial Hall, 19th and Locust Streets. PROGRAM. “ Intensive Scrubbing and Condensing of Gas,” by L. E. Worthing, Detroit, Mich. “The Manufacture of Illuminating Gas in ByProduct Ovens in the United States,” by W. S. Blauvelt, Semet-Solvay Company, Detroit, Mich. “Report on Verticals a t Providence, R. I.,” by Carroll Miller, Providence, R. I. “Report on Verticals a t Manchester, N . H.,” by 1%’. G. Africa, Manchester, N. H. Turbo-Blower,’’ by an engineer with the General Electric Company. “Production and Market for Sulphate of Ammonia,’’ by a n engineer with the ?Jew England Gas and Coke Company, Boston, Illass. Tar Distillation and Market for its By-products,” by Alan D. Whittaker, Atlanta, Ga. ’ ’ Actual Leakage in Unaccounted-for Gas,” by J . D. von Maur, St. Louis, M o . ‘ I
