Chapter XIV: Part 14

_Separation of Phosphoric Acid._—The united filtrates from the two determinations are placed in a graduated flask and made up to the mark. An aliquot portion of this solution representing half a gram of the original ash or any other convenient quantity is transferred to a beaker and a solution of ferric chlorid added until ammonia produces a brown precipitate in the mixture. Neutralize with ammonia and hydrochloric acid alternately until the liquid is as little acid as it can be and still remain clear. Add from ten to twenty cubic centimeters of a solution of sodium acetate (1:10) and bring to a boil. The liquid should be quite dilute. Filter and wash free of chlorids with boiling water containing some sodium acetate.

_Manganese._—Make the filtrate faintly alkaline with ammonia and add ammonium sulfid. Any manganese sulfid which may form is separated by filtration, treated with dilute acetic acid and the resulting solution, which should be clear, heated to boiling, nearly neutralized with caustic soda, and mixed with bromin water. The resultant manganese dioxid is to be filtered into a gooch, ignited and weighed as Mn₃O₄.

_Lime._—Reacidify the filtrate from the manganese sulfid with acetic acid, heat to boiling and add ammonium oxalate: Allow to stand over night, filter through a gooch and wash with water containing acetic acid. The calcium oxalate can be weighed as such, but it is preferable to dry thoroughly and then heat in a small bunsen flame until a change can be noted passing over the precipitate. If this is carefully done the residue will be calcium carbonate. In any case the result is to be checked by igniting over the blast lamp to constant weight and weighing the lime thus obtained.

_Magnesia._—In the filtrate the magnesia can be determined by sodium phosphate in the usual manner. In very accurate work the calcium oxalate obtained as directed above can be dissolved and reprecipitated, and the magnesia in the filtrate added to that in the first filtrate.

_Iron._—For iron another aliquot portion of the original solution is taken, acidified with sulfuric evaporated to drive off hydrochloric acid, rediluted and passed through the Jones reductor described in paragraph =112=. The filtrate is titrated with potassium permanganate solution in the usual manner.

_Alkalies._—For the alkalies another aliquot portion is taken and precipitated while hot, with barium chlorid and barium hydrate, filtered, and ammonia and ammonium carbonate added to remove the excess of barium salt. Refilter, evaporate to dryness in a platinum dish, and ignite gently to expel all ammonia salts, repeat this operation after taking up with water and finally heat to constant weight. The weight obtained represents a mixture of potassium and sodium chlorids, with usually carbon derived from impurities in the ammonia. A little magnesia is often present. The potassium is estimated by means of platinum solution, and the potassium chlorid found deducted from the total weight gives the sodium chlorid. The carbon is usually unweighable, though it often looks as if present in considerable quantity. It may be estimated, however, by dissolving the mixed chlorids in weak hydrochloric acid and filtering through a gooch before making the potassium estimation. The estimation of the magnesia remaining with the mixed chlorids may be effected by evaporating the alcoholic solution remaining after the precipitation of the potassium to dryness, redissolving in water, placing the solution in a flask provided with gas tubulures, introducing hydrogen, and placing in the sunlight. The platinum is soon reduced, leaving the liquid colorless. Heating facilitates the reaction. Displace the hydrogen by a current of carbon dioxid, filter, concentrate the solution and precipitate the magnesia by sodium phosphate in the usual manner.

_Phosphoric Acid._—It is best to determine the phosphoric acid directly in an aliquot part of the first filtrate from the hydrochloric acid solution of the ash obtained as described under the determinations of sand, silica and carbon. When there is not enough of the material for this, the precipitate of ferric phosphate may be dissolved and the phosphoric acid determined after separation with ammonium molybdate.

_Sulfuric Acid._—Fifty cubic centimeters of the original hydrochloric acid filtrate, obtained as described under the determinations of sand, silica and carbon, are heated to boiling, and the sulfuric acid thrown out by the gradual addition of barium chlorid. During the precipitation the mixture is kept at the boiling temperature, but taken from the lamp and the precipitate allowed to settle from time to time until it is seen that an additional drop of the reagent causes no further precipitate. The barium sulfate is collected, dried, and weighed in the usual manner.

_Chlorin._—Dissolve from one to five grams of the ash in nitric acid in very slight excess, or in water. If the solution be made in nitric acid the excess must be neutralized if the chlorin be determined volumetrically; and if the solution be in water, nitric acid must be added if the determination be gravimetric.

The volumetric determination is accomplished in the usual manner with a standard silver nitrate solution, using potassium chromate as indicator. The gravimetric determination is effected by precipitation with silver nitrate, collecting, washing, and drying at 150° the silver chlorid obtained.

_Carbon Dioxid._—The carbon dioxid is most conveniently estimated in from one to five grams of the ash, according to its richness in carbonates, by the apparatus described in volume first, or some similar device.[252]

=298. Official Method for Determinations of the Alkalies.=—Evaporate the filtrate and washings from the sulfuric acid determination, paragraph =297=, in a porcelain dish to dryness, redissolve in about fifty cubic centimeters of water and add milk of lime, or barium hydroxid solution, which must be perfectly free from alkalies, until no further precipitation is produced, and it is evident there is an excess of calcium hydroxid or barium hydroxid present; boil for two or three minutes, filter hot, and wash thoroughly with boiling water, precipitate the lime and baryta from the filtrate with ammonia and ammonium carbonate, filter, evaporate the filtrate to dryness in a porcelain dish, and drive off the ammonia salts by heat below redness.[253] When cold, redissolve in fifteen or twenty cubic centimeters of water, precipitate again with a few drops of ammonia and ammonium carbonate solution, let stand a few minutes on the water-bath and filter into a tared platinum dish and evaporate to dryness, expel the ammonia salts by heating to just perceptible dull redness, weigh the potassium and sodium chlorids obtained and determine the potassium chlorid with platinic chlorid as usual.

The potassium may also be determined by the perchlorate method, or the total chlorin be determined volumetrically, and the relative percentages of potassium and sodium chlorids calculated by the usual formula: Or multiply the weight of chlorin in the mixture by 2.1035, deduct from the product the total weight of the chlorids and multiply the remainder by 3.6358. The product expresses the weight of the sodium chlorid contained in the mixed salts. The indirect method is only applicable when there are considerable quantities of alkalies present and where they exist in approximately molecular proportions. It is therefore a process rarely to be recommended in ash analysis.

=299. Statement of Results.=—The bases which are found present in the ashes of wood and other vegetable tissues exist without doubt before incineration, chiefly in combination with inorganic acids. Even the phosphorus and sulfur which after ignition appear as phosphates and sulfates, have previous thereto existed in an organic form to a large extent. The silica itself is profoundly modified in the organism of the growing plant and doubtless does not exist there in the purely mineral form in which it is found in the ash. During the progress of incineration, with proper precautions, all the phosphorus and sulfur are oxidized and appear as phosphoric and sulfuric acids. The silica is reduced to a mineral state, and if a high heat be employed silicates are formed. The organic salts of lime, magnesia and other bases at a low temperature are converted into carbonates, and if a higher temperature be used, may appear as oxids. The organic compounds of alkalies will be found in the ash as carbonates. It would be useless, therefore, to try to state the results of ash analysis in forms of combination similar to those existing in the original vegetable tissues. It is not certain even that we can in all cases judge of the form of combination in which the different constituents exist in the ash itself. It is therefore to be preferred in a statement of ash analysis to give the bases in the form of oxids, and the sulfur and phosphorus in the form of anhydrids, and the chlorin in its elementary state. In this case an equivalent amount of oxygen to the chlorin found must be subtracted from the total. If an attempt be made to combine the acid and basic elements the chlorin should first be united with sodium, and any excess thereof with potassium, and the amount of base so combined calculated to oxid and deducted from the total of such base or bases present. The carbonic acid present should be combined first with alkalies after the chlorin has been supplied. The phosphoric acid should be combined first with the iron and afterwards with lime or magnesia. In all cases the percentages should be based upon the ash, after the carbon and sand have been deducted, or it is also convenient at times to throw out of the results the carbon dioxid and to calculate the other constituents to the ash free of that substance. In determining the quantities of mineral matters removed from soil by crops, the ash should be determined with great care, freed of carbon and sand, and the calculations made on the percentage thus secured. In all statements of percentages of the essential constituents of ash, as regards fertilizing materials, it should be specified whether the percentage is calculated on a crude ash, the pure ash, that is free of carbon and sand, or upon a basis excluding the carbon dioxid. For the purpose of fertilizer control, the analyst and dealer will be satisfied, as a rule, with the determination of the percentages of phosphoric acid and potash alone. To the other constituents of an ash is not assigned any commercial value.

AUTHORITIES CITED IN PART FOURTH.

[239] Compiled for author by Mr. K. P. McElroy.

[240] Volume First, pp. 356 et seq.

[241] Volume First, pp. 337 and 390.

[242] Volume Second, p. 81.

[243] Day: Mineral Resources of the United States, 1893, p. 713.

[244] Frankland: Agricultural Analysis, p. 240.

[245] Volume Second, p. 9.

[246] Annual Report Connecticut Agricultural Experiment Station, 1888, Part 1, p. 80.

[247] Rapport addressé par le Comté des Stations Agronomiques, 1887, p. 34.

[248] Agricultural Science, Vol. 8, pp. 2 and 3, 1894, and Massachusetts Agricultural Station, 12th Annual Report, pp. 285 et seq.

[249] North Carolina Agricultural Experiment Station, Bulletin No. 3.

[250] Bulletin No. 43, Chemical Division, U. S. Department of Agriculture, p. 390.

[251] Compiled for author by Mr. K. P. McElroy.

[252] Volume First, p. 337.

[253] Vid op. cit. 12, p. 391.

INDEX.

A
Page.
Acid phosphates, definition, 150, 151
Albuminoid nitrogen, separation, 225
Alkalies, determination in ashes, 320, 321
official method for determination in ashes, 322
Alkaline earths in wood ashes, 317
Amid nitrogen, separation, 225, 228
Ammonia, preparation for washing precipitates, 17
Ammoniacal nitrogen, 166
separation, 226
Ammonium citrate, influence of
acidity and alkalinity on solvent power, 137, 138
movement on solvent power, 141
quality of sample on solvent power, 136
temperature on solvent power, 134
time on solvent power, 133
preparation, 44
solvent for phosphoric acid, 132
nitrate solution, preparation, 45
Animal débris, treatment, 11
Aqueous vapor, measurement of tension, 180, 181
Arsenic, error, 54
Asboth, method for nitrogen, 212
Ashes, analysis, statement of results, 323, 324
composition, 252
fertilizing value, 254
percentage in various woods, 253
Authorities cited in Part First, 156-160
Fourth, 324
Second, 246, 247
Third, 300, 301

B
Barium oxalate, reagent for potash determination, 281
Barometer, method of use, 178, 179
Basic phosphatic slags, technical analysis, 123
slags, Dutch method for analysis, 77
Halle method for analysis, 76
Berzelius, method of estimating fluorin, 35, 36
Blood, dried, 165
Brown, separation of iron and alumina in phosphates, 131

C
Calcium carbonates, function in manufacture of superphosphates, 152
fluorids, reactions, 152
Carbon dioxid, determination in ashes, 322
phosphates, 19
estimation, 19
in wood ashes, 315, 319
Carnallit, 260
method for analysis, 274-277
Cave deposits, 312
Chatard, modification of Berzelius method, 35-37
Glaser-Jones process, 30, 31
organic matters in phosphates, 18
Chile saltpeter, 168, 235
adulteration, 234
analysis, 234
application, 240
commercial forms, 233
consumption, 245
Gantter’s method, 236-238
method of difference, 239, 240
French sugar chemists, 236
percentage of nitrogen, 233
quantity applied, 244
zinc-iron method, 234, 235
Chlorin, determination in ashes, 322
Chromium, occurrence in phosphates, 128
Citrate and molybdate methods, comparative accuracy, 69
insoluble phosphoric acid, 41
method, 57-59
applicability, 145, 146
Swedish modification, 66, 67
soluble phosphoric acid, 44
direct precipitation, 147
Dutch method, 68
Coloration of distillate, 187
Combustion furnace, 175
Copper oxid combustion, 170
Cottonseed hulls and meal, composition, 251
Crispo, method of estimating iron and alumina, 29, 30

D
Dilute ammonia, preparation, 45
Distillate, coloration, 187
Distillation apparatus, 208
Dudley and Pease, determination of phosphoric acid
in the presence of iron, 113

F
Factors for calculating potash analysis, 270
phosphoric acid analysis, 17
Ferric phosphate in wood ashes, 317, 318
Ferrous sulfate, analysis, 310, 311
uses, 310
Fertilizers, cost of transportation, 2
definition, 1
drying samples, 12
German methods, 13
official methods, 13
natural, 1
objects of analysis, 1
sampling mixed, 6
French method, 7
method of French sugar chemists, 7
treatment of samples in laboratory, 10
Fertilizing ingredients, trade values, 3
valuation, 2
materials, minerals containing, 5
sampling organic, 8
Fish scrap, 134
Fluorin, estimation in phosphates, 35-38
occurrence in bones, 130

G
German experiment stations, methods for determining
phosphoric acid, 45, 46
Glaser method for estimating iron and alumina, 24, 25, 27
Gooch distillation method, 19
Green vitriol, analysis, 310, 311
uses, 310
Grinding apparatus for fertilizers, 6
Guanos, 312
analysis, 313
nitrogen content, 166
origin, 167
Gunning method, 216, 217
adapted to nitrates, 220
official, 219
for nitrates, 220
process, reactions, 218
Gypsum, 307
amount used, 307
analysis, 308, 309
use for composting, 307, 308

H
Halle method for potash, 270, 271
Hen manure, 312
Hess, method for estimating iron and alumina in phosphates, 25, 26
Holleman, silver method for phosphoric acid, 117
Horn, hoof, and hair, 165
Huston, calcium chlorid method, 282
digestion apparatus, 142, 143
mechanical stirrer, 144, 145
solubility of reverted phosphoric acid, 132, 139

I
Immendorff, method for estimating lime, 23
Indicator for nitrogen determination, 204
Iodin, determination in phosphates, 127
Iron, acetate method, 24
determination in ashes, 320
estimation in phosphates, 24-26, 28-31

J
Jodlbaur method, Dutch variation, 213, 214
for nitrogen, 212, 213
Halle modification, 214
Johnson and Jenkins, method for nitrogen, 177
citrate method, 59
comparison of citrate and molybdate methods, 69, 70
Jones modification of Glaser method, 28
reductor, 115
Jüptner, tartaric acid solution, 17

K
Kainit, 259
methods for analysis, 274-277
Kieserit, 263
methods for analysis 274-277
Kjeldahl method, 192-216
Dutch process, 200
Halle process, 200-204
modifications, 209-216
official for nitric nitrogen, 215
process, 204-207
original process, 193-196
preparation of reagents, 167-199
theory of reactions, 197
Knorr apparatus for carbon dioxid, 19
Kreider, perchlorate process, 296
Krug and McElroy, estimation of iron and alumina
in phosphates, 32, 33
Krugit, 262

L
Land plaster, 317
Leather waste, 314
Lime, action, 303-305
analysis, 305
application, 303
as a fungicide and insecticide, 305
compounds used as fertilizer, 302
determination, in ashes, 320
of state of combustion, 306, 307
estimation in basic slags, 80, 81
phosphates, 21-23, 35
of caustic, 81
preparation of sample, 306

Mc
McElroy, method of analysis for wood ashes, 319-322
separation of iron and alumina from phosphoric acid, 33, 34

M
Manganese, determination in ashes, 320
Magnesia, determination in wood ashes, 320
error due to occluded, 54
estimation in phosphates, 35
mixture, preparation, 17, 45
removal in perchlorate process, 298
Magnesium compounds, action in manufacture of superphosphates, 154
nitrate, preparation, 45
pyrophosphate, color, 55, 56
Manure, definition, 1
sampling barnyard, 9
Marioni and Fasselli, modification of Glaser’s method, 31, 32
Mercury pump, 173, 174
Mills for crushing fertilizing minerals, 5
Minerals containing fertilizing materials, 5
Moist combustion process, historical, 192
Moisture, determination in ashes, 219
in monocalcium phosphates, 13, 14
Molybdate and citrate methods, comparative accuracy, 69
method, adopted by Brussels congress, 67
sources of error, 53
Molybdedum precipitate, direct weighing, 150
Molybdic solution, preparation, 17, 45
Morgen, citrate method, 60-65

N
Neubauer, investigation of error, 54, 55
Nitric nitrogen, 168
estimation, 227
Krüger’s method, 231
Schlöesing-Wagner method, 228, 229
Schmitt’s modification, 230
Ulsch method, 227
separation, 226
Nitrifiable solution, 243
Nitrogen analysis, calculation of results, 177
table for calculating results, 183
as ammonia, 221, 222
determination by Boussingault, 222, 223
cost per pound, 3, 4
forms of occurrence, 161, 162
kinds in fertilizers, 161
method of volumetric determination in laboratory, 175, 176
methods of analysis, classification, 169
official methods, 170
volumetric method, 171, 172
qualitative determination of form, 162, 163
Nitrogenous fertilizers, source, 163, 169
Norwegian methods, 45, 47
Noyes and Royse, determination of phosphoric acid
in the presence of iron, 113, 114

O
Official method for phosphoric acid, 16
volumetric method, rarely used, 173
Ogilvie, separation of alumina from phosphoric acid, 31, 32
Organic fertilizing materials, sampling, 8
matters, destruction, 255
by moist combustion, 256
sulfuric acid, 56, 57, 147, 148
in phosphates, 39
ignition with sulfuric acid, 255
in phosphates, 18

P
Patrick, distilling flask, 209
Pemberton method, comparison with official, 109
of preparing reagents, 107, 108
volumetric method for phosphoric acid, 106
Perchlorate process, accuracy, 300
applicability, 299
comparison of results, 298
method of Kreider, 296, 297
Perchloric acid, composition, 295
keeping properties, 295
preparation, method of Caspari, 290, 291
Kreider, 292-294
reagent for potash, 286
Phosphates, constituents to be determined, 15
insoluble matter, 20
low cost, 3
moisture in monocalcium, 13, 14
natural manurial value, 4
preparation of solution, 20
soluble matter, 19
Phosphatic fertilizers, availability, 148, 149
slags, adulteration, 81
detection, 82-86
analysis, 75-81
manufacture, 71, 72
solubility, 74
Phosphomolybdic acid, reagent for potash, 289
Phosphoric acid, condition in superphosphates, 101
cost per pound, 3
determination as stannic phosphate, 40
by official method, 16
titration of yellow
precipitate, 106-110
in ashes, 321
basic slag, 51
bone meal, 51
fish-guano, 51
mineral phosphates, 51, 53
superphosphates, 50
direct estimation, 15
Dutch method of determination, 51-53
error due to volatility, 54
estimation as a lead compound, 110
in presence of iron, 112
molybdenum technical method, 120, 121
preparation of reagents for technical
determination, 118, 119
separation in wood ashes, 319
silver method, 116, 117
sources, 39
Swedish methods of determining, 49, 50
technical determination, 118-125
volumetric uranium method, 121, 122
time required for precipitation, 126
typical solution, 95
used for superphosphate manufacture, 156
volumetric determination, 86-118
Platinic chlorid, method for potash, 267
official, 267, 268
Platinum method, sources of error, 284, 285
waste, recovery, 287-289
weighing metallic precipitate, 283, 284
Polyhalit, 261
Potash analysis, classification of methods, 266
consumption, 265, 266
cost per pound, 4
Dutch method for analysis, 272
estimation as perchlorate, 289-300
table of factors, 287
forms found in fertilizers, 249
Halle method for analysis, 270, 271
in molasses, 254
winery residues, 255
methods of analysis, 266-300
occurrences in mineral deposits, 256, 257
official alternate method, 269
recovered from factory residues, 265
salts, changes in situ, 257
control method for analysis, 283
effect of concentration on accuracy of
analysis, 285, 286
geological occurrence, 258
methods for analyzing concentrated, 278-280
solution from organic compounds, 270
sources, 248
Swedish method for analysis, 273
Potassium hydroxid solution, tension of vapor, 182
magnesium carbonate, 265
platinochlorid, differences in crystalline form, 286
sulfate, grades as fertilizers, 264
Pyrophosphate, examination, for impurities, 126

R
Reverted phosphates, reversion by ammonium citrate, 103, 104
phosphoric acid, arbitrary determination, 139
definition, 139, 140
determination by uranium method, 102
Robinson, sources of error in platinum method, 284, 285
Roode, de, method for kainit, 281
Ross, direct precipitation of citrate soluble phosphoric acid, 147
Ruffle method, 188
Boyer’s modification, 190, 191
official, 188-190

S
Salt, 309
analysis, 310
Samples, directions for taking bulk, 243
French method of preparation, 10
German method of preparation, 10
official method of preparation, 10
special cases, 12
taking, 4
Sanborn, method of filtering phosphoric acid, 42
Sand in wood ashes, 315, 316, 319
Schönit, 264
Schweitzer and Lungwitz, method for potash, 281
Scovell, method for nitrogen, 215
Seeds and seed residues, 163
Shaking apparatus, 78, 79
Silica, error due to occluded, 53
estimation in phosphates, 20
in wood ashes, 315, 316, 319
Slags, basic phosphate, 70
composition, 72, 73
manufacture, 71, 72
Soda-lime process, 183, 184
French method, 186
hydrogen method, 187
official method, 184-186
preparation of samples, 187
Sodium nitrate, functions, 231, 232
value, 246
Soluble phosphoric acid, determination by uranium method, 102
German method of estimating, 47, 48
Spencer, silver method for phosphoric acid, 116
Stall manures, 311
Stannic chlorid, reagent for determining phosphoric acid, 40
Sterilized tubes, for sampling, 241
Stone and Scheuch, estimation of caustic lime, 81
Sulfuric acid, determination in ashes, 321
estimation in phosphates, 35
quantity used in the manufacture of
superphosphates, 154, 155
removal in perchlorate process, 298
Superphosphates, action of iron and alumina compounds
in manufacture, 153
chemical reactions in manufacture, 151
definition, 150, 151
determination by uranium method, 102
manufacture, 150-156
with phosphoric acid, 156
quantity of sulfuric acid used
in manufacture, 154, 155
technical analysis, 124, 125
Sylvin, 262
Sylvinit, 263
methods for analysis, 274-277

T
Tankage, 165
Tartaric acid, use, in molybdenum solution, 17
Tetracalcium phosphate, molecular structure, 73
Thiocyanates in fertilizers, determination, 224
Tobacco stems, 250
and waste, composition of ash, 250
waste, 250
Total phosphoric acid, treatment, 42, 43

U
Uranium method for phosphoric acid, 88-101
preparation of standard solution, 94
process, causes of errors, 98, 99
correction, 97
titration of sample of phosphate, 100
solution, titration, 96

V
Vanadium, methods of estimation, 128, 129
Van Slyke, reactions of gunning method, 218
Voorhees, method for nitrates, 220

W
Waste matters as fertilizers, 2
Water, determination in phosphates, 18
soluble phosphoric acid, 41
volumetric estimation, 111
Wells, citrate method, 59
Wilfarth, method for nitrogen, 211
Winton and Voorhees, gunning method for nitrates, 220
potash analysis, 285, 286
Wood ashes, 251, 315
composition, 252
Wyatt, method for determining iron and alumina in phosphates, 34
estimating fluorin, 37, 38
lime, 22