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TABLE VI.
EFFECT OF
COATING SOYBEAN MEALIMPREGNATED W I T H VIT.4MIN IMMEDIATELY BEFORE ADDINGDESTRUCTIVE MATERI.4LS
Coating Agent None cla stearate
-
Destructive Material Added Later 1 mo. Dried whey 70 Dried whey 100
Per Cent of Original Potency 4 ma. 6 mo. 8 mo. 10 ma. 12 mo.
2 mo.
30 100
...0
96 100
73 100
0 100
... 100
...
8 100
0 100
...
100
None Hydrogenated fat
Dried whey Dried whey
... ...
None Hydrogenated fat
Mineral mixt. Mineral mixt.
45 100
None Hydrogenated f a t Hydrogenated f a t Hydrogenated fat
Mineral Mineral Mineral Mineral
mixt. mixt. mixt. mixt.
...
None iMolasses
Mineral mixt. Mineral mixt.
...
...
D OIL
...
94
...
15 86
... ...
...
..
...
.. .. .. .. .. .. .. .. .. ..
... ...
75
50
.,.
...
... 81 ...
100
... ...
.. ..
.. ..
18 86
..
., .. ~. .. .. .. .. ..
.. .. ,.
..
72
80
.. ..
..
Vol. 34, No. 8
The addition of hydroquinone to the fish oil prior to addition of the oil to minerals did not protect the vitamin D from subsequent destruction. A limited number of observations showed the same rate of vitamin D loss, regardless of whether the oil did or did not contain hydroquinone. The limited quantity of hydroquinone which could be used in this manner may have made this use less effective than the addition of dry hydroquinone to the carrier before addition of the oil.
Acknowledgment dants in his studies on the autoxidation of lard. Hydroquinone was used in finely powdered form a t a 2 per cent level. Since powdered sodium thiosulfate has been found to protect potassium iodide in feeds, this compound was similarly tried a t a 2 per cent level. The work of Dahle and Nelson (3) and others indicated that oat flour contains antioxidants. Twentyfive per cent of oat flour was tested. The results are summarized in Table VII. Partial protection was afforded by the oat flour and by the hydroquinone but not by the thiosulfate under the conditions of this test.
T.4BLE
VII.
EFFECT O F ANTIOXIDANTS ON VITAMIND .
Antioxidant, None Hydroquinone, 2 Sodium thiosulfate, 2 Oat flour, 25
STABILITY O F
yo of Original Potency after 3 Ma. 0 39 0
64
The authors express their appreciation to Xutrition Research Laboratories for the gift of the activated ergosterol used in this study, and to Winthrop Chemical Company, for the gift of the crystalline vitamin D,.
Literature Cited (1) ilssoc. of Official Agr. Chem., Official and Tentative Methods of Analysis, 5th ed., 1940. (2) Bird, H . R., personal communication, 1941. (3) Dahle, C. D . , and Nelson, D. H., J. Dairy Sci., 24, 29-39 (1941). (4) Ewing, W. R., Handbook of Poultry Nutrition, pp. 454-8 (1941). (5) Fritz, J. C., Archer, W. F., and Barker, D. K., Ann. Meeting Poultry Sci. Assoc., Stillwater, Okla., 1941. (6) Johnson, F. F., and Frederick, E. R., Science, 92, 315-16 (1940). (7) -Murlin, J. R., Federation of Am. SOC.for Expt>l.Biol., Boston, 1942. (8) Olcott, H. S., J. Am. Chem. SOC.,56,2492 (1934). (9) U. S. Pharmacopoeia XI, 2nd Supplement, 1939. PRESENTED in a program on “Vitamins” before a joint session of the Divisions of Biological Chemistry and of Agricultural and Food Chemistry a t the 103rd Meeting of the AJIERICAN CHEJIICAL SOCIETY, Memphis, Tenn.
Phosphine and Sludge Digestion WILLEM RUDOLFS AND GLENN W. STAHL New Jersey Agricultural Experiment Station, Rutgers University, Yew Brunswick, N. J.
ETTLED sewage solids may contain from 0.75 to 3.0 per cent phosphorus as P206, whereas in digested sludge the content ma.y vary from 1.0 to 4.0 per cent on a dry solids basis. Sludge obtained from chemically treated sewage may contain considerably more. The apparent increase in phosphorus in the sludge after digestion is un‘doubtedly due to the destruction of organic matter by biological activities. Since living things require phosphorus and the organic matter undergoes profound changes, it is probable that during these changes the organic phosphorus compounds pass through several stages before the phosphorus is “mineralized” arid left in the residue. It is conceivable that in the course of these changes a portion of the phosphorus is produced in gaseous form and evolves from the sludge mixed with the other gases formed. Two hydrides of phosphorus, pK3 and (pHz),, which eshibit properties of interest in connection with hazards, are known. The first, phosphine, is an extremely poisonous gas, the formation of which has been reported during the bacterial reduction of organic and inorganic phosphorus compounds.
S
Rawn, Banta, and Pomeroy ( I O ) reported it as a constituent of digestion tank gases. The second, hydrogen hemiphosphide, is a spontaneously flammable substance which usually occurs as an impurity in phosphine, especially when the latter is prepared under alkaline conditions. If phosphine is produced with regularity from phosphorus compounds during sludge digestion, it is possible that apparently spontaneous digestion tank explosions might be due to the presence of such small traces of hydrogen hemiphosphide as commonly occur along with phosphine. For explosion it is necessary that oxygen be present. Oxygen for explosive combination with the gases may be present when digested sludge is drawn and air allowed to enter a tank or when digester gases leak into confined spaces where air is present. Kumerous investigators have been interested in the production of phosphine from both organic and inorganic materials, but many contradictions in the results obtained are found in the literature. One of the earliest reports on the production of phosphine is that of Selmi (II), who found that during the anaerobic decomposition of egg yolk, albumin.
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and brain pastes, a gas resembling phosphine was produced. Positive results with the same media were also obtained by Baf-bieri( I ) , Stich ( l a ) ,Kulka ( 8 ) ,and Kreps (7), but Hallefreund (6),Hallasz (4), and Lemkes (9) obtained negative results with these media. Fresenius and Neubauer (3) found that no phosphine was produced from feces inoculated with magnesium ammonium phosphate. Klett (6) found that a nutrient medium containing sodium metaphosphate gave negative results as did Fischer (a) working with monoand trisodium phosphates and B. coli. Kulka's investigation of brains and egg yolk inoculated with B. putrefactus gave phosphine without exception. A sample of gas taken by the same author from a digestion tank near Baden in the neighborhood of Vienna was stated to analyze 0.6 cc. of phosphine per liter of gas. There is no doubt that a considerable part of the discrepancy in these results may be ascribed to the difficulty with which small amount of phosphine can be determined quantitatively and qualitatively in the presence of interfering FIGURE1. APPARATUS FOR ANALYSISOF GASES PRODUCED gases such as hydrogen sulfide, which are also produced in the I. 2.5-liter container with digestion mixture, fitted with rubber balloon course of anaerobic decomposition. Yakote (IS),in checking to regulate gaB pressure the work of previous investigators, found that a number of 11. Sorption tube with soda lime 111. Washing bottle with reagent for phosphine positive results were due to the transference of phosphorus IV. Safety trap from the rubber used in apparatus employed. These diffiV. Graduated gas collector culties were not apparent during the ppesent investigation because the use of silver nichlorine water and determined trate as a qualitative test was as nhosohomolvbdate. The designated- as nonspecific for The possible production of phosphine durvolumes of gas "produced during digestion of sewage solids was investiing digestion were recorded. phosphine. Yakote also found that silica interferes with the gated through the addition of various The procedure for phosphine determination of phosphorus analysis was as follows: organic and inorganic phorphorus comby the molybdate method, beGas produced by the dicause of the precipitation of a Pounds to digesting sludge mixgesting mixtures was passed tures. All of the phosphorus compounds through sorption tubes consilicomolybdate rather than a studied gave qualitative tests for phosphine taining soda lime to remove phosphomolybdate. Kulka at variousstages during digestion, but hydrogen sulfide, which would also asserts that silver- and lead-treated papers gave aminterfere with the qualitative were confirmed when the gas produced was biguous results. tests for phosphine (Figure l). From the inconclusiveresults ' Oxidized with chlorine and the PhosPhorus The gas was then passed reported in the literature it determined as phosphomolybdate, using through a washing bubbler conwould appear that the productaining silver nitrate, mercuric silica-free agents. tion of phosphine through the chloride, or copper sulfate if bacterial reduction of phosthe qualitative tests were being phorus compounds is still an open question. The theoretical run or through chlorine \+ater if a quantitative determination and practical interest in such phosphorus compounds being was being made for the verification of a previously obtained produced in digesters and the possibility of explaining several qualitative test. These gas bubblers were especially sensitive explosions which have occurred during recent years led to the to the presence of phosphine, for during the tests with gases experimentation reported in this paper. known to contain phosphine (from calcium phosphide and water) the precipitate formed in the interior of the fritted Methods and Materials bubbler and thus greatly enhanced the visibility as well as To determine whether ,phosphine is produced during the the color of the precipitate. Less than 1 mg. of silver phosphide was easily discernible. . Solutions of sodium hydroxide digestion of seeded fresh solids in the presence of phosphorus compounds, various quantities of calcium monophoswere not used as absorbents for hydrogen sulfide because of phate, Ca(H2P0&.H20, ammonium dihydrogen phosphate, the tendency to suck back into the digestion flask due to a NH4H2P04,sodium metaphosphate, NaP03, trisodium phoslowering of the gas pressure within the flask. After being phate, Na3P04.12H20, sodium hypophosphite, NaHzPOz.H20, passed through the various absorbents, the gas was finally collected in a graduated bottle and the volume measured a t casein, albumin, and egg yolk were added. Calves' brains, inoculated with sewage mixtures and ripe sludge, were in20" C. over water. This temperature was maintained cluded in the study. throughout the course of the digestion. The materials were mixed on the basis of 4 parts volatile Results matter in the ripe sludge to 1 part in the fresh solids. I n another series various quantities of the phosphorus compounds Mixtures of ripe sludge and fresh solids alone or treated were mixed with fresh solids and ripe sludge on the volatile with casein, albumin, egg yolk, trisodium phosphate, calcium matter ratio of 5 to 3. The added phosphorus compounds monophosphate, sodium metaphosphate, monoammonium were dissolved in a small amount of water and added to the phosphate, and sodium hypophosphite in no instance were digestion' mixtures or suspended in the mixture by thorough found to yield phosphine. Any qualitative tests indicative shaking. Analyses of phosphine in the gas were made of phosphine with silver nitrate, mercuric chloride, and copper qualitatively by means of copper sulfate, silver nitrate, or sulfate did not indicate phosphorus when the gas was oxidized mercuric chloride, and quantitatively by oxidation with with chlorine water and treated with ammonium molybdate. L
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Calves’ brains inoculated with the digesting mixtures and ripe sludge gave qualitative but no quantitative test for phosphine. That phosphine was not being lost through absorption by the soda lime was confirmed by passing samples of gas known to contain phosphine through the apparatus. Distillation of the contents of the digestion flasks after digestion eliminated the possibility of the phosphine remaining dissolved in the digestion mixture. The absence of phosphine in the gases evolved from the various digestion mixtures confirms the results obtained by Hallefreund, Hallasz, Lemkes, Fresenius and Neubauer, Klett, and Fischer. All of the phosphorus compounds studied gave qualitative tests for phosphine a t various stages in the experimentation, but none were confirmed when the gas was oxidized with chlorine water and the phosphorus determined as phosphomolybdate, using silica-free reagents. This is in agreement with the report by Yakote on the lack of reliability of the qualitative tests. That phosphine did not remain in the digestion mixture was confirmed by passing a stream of nitrogen through the boiling digestion residue. The report by Kulka that digester gas may contain 0.06 per cent phosphine is not confirmed by these experiments. The
Vol. 34, No. 8
concentration of 0.0001 per cent phosphine in digester gas as reported by Rawn, Banta, and Pomeroy (IO) would correspond to approximately 0.015 mg. of silver phosphide from each liter of gas. This quantity is outside the sensitivity of the reagents and apparatus used in the above experiments. On the assumption that phosphine was actually present, this quantity remains as the probable upper limit of phosphine content of digester gases.
Literature Cited Barbieri, Comp. rend., 131, 347 (1900). Fischer, Pfliigers Arch. Ges. Physiol., 97, 601 (1903). Fresenius and Neubauer, 2. anal. Chem., 1, 343 (1862). Hallase, 2. anorg. Chem., 26, 438 (1901). Hallefreund, dissertation, Erlangen, 1890. Klett, 2. Hyg. Infektionskrankh., 32, 155 (1900). Kreps, Pfliigers Arch. Ges. Physiol., 97,601 (1903). Kulka. Zentr. Bakt. Parasitenk., 1, 61, 336 (1912). Lemkes, Chem. Zentr., 1, 604 (1917). Rawn, Banta, and Pomeroy, Proc. Am. Soc. Civil Engrs., 65, P t . 2, 108 (1939). Selmi, Acad. de Bologna, Series 3, p. 8 (1928). Stioh, Chem. Zentr., 1, 1 4 (1901). Yakote, Arch. Hyg., 50, 118 (1904).
Removal of Metallic Contaminants from Pine Oleoresin Washing with Mineral Acid RAY V. LAWRENCE Naval Stores Station, Bureau of Agricultural Chemistry and Engineering, U. S. Department of Agriculture, Olustee, Fla.
The use of dilute mineral acid for washing diluted filtered oleoresin, badly contaminated with iron, makes it possible to produce rosin of much lighter color than can be obtained from the unwashed oleoresin. As much as 85 per cent of the metallic contaminants present in crude oleoresin can be removed by washing with dilute mineral acid. No appreciable difference was noted in the effectiveness of the acids used (hydrochloric, nitric, or sulfuric).
OSIN produced in this country is of two types, wood rosin and gum rosin. Wood rosin, along with other constituents, is extracted by a petroleum solvent from resinous stumps and “down wood” of the pine tree. Gum rosin is the residue remaining in the still after the turpentine has been steam-distilled from the oleoresin obtained from the living pine.
R
The flow of oleoresin is induced by periodically wounding certain species of pines. This exudate is collected by attaching metal strips, known as gutters and aprons, to the face of the tree t o guide the oleoresin into a cup which is hung below the freshly wounded portion. The gutters and aprons are usually made of galvanized iron, and the cups are of galvanized iron or clay. The oleoresin eventually removes most of the zinc from the galvanized iron, after which the oleoresin becomes contaminated by the exposed iron. Rosin is graded and sold on the basis of color, the paler colors bringing the higher prices. The color grades of rosin range from a pale yellow in grade X to a dark red (almost black) in grade D, increasing progressively through the grades T V W , WG, N,M, K, I, H, G, F, and E. The color degradation of gum rosin is due principally to iron contamination and, to a lesser degree, t o oxidation products. This is especially true in the medium and lower grades. The presence of 0.1 per cent of iron in rosin is usually sufficient to lower the grade from X to D. Wood rosin that is produced directly from the extracting solvent without refining is ruby red in color and is known as FF wood rosin. The coloring matter present in wood rosin is due principally to organic compounds extracted from the wood by the petroleum solvent. The removal of these color bodies from wood rosin is the subject of numerous patents. Practically all of these patents depend on one or more of the following methods (4): vacuum distillation of the rosin, use of selective solvents for removing the color bodies present in the gasoline solution of rosin, absorption of the color bodies by activated carbon and fuller’s earth, and
