cipitation, so lime was added to the liquor to precipit'ate the free sulfur dioxide as calcium sulfite. The n e u t r a l i z e d liquor gave considerable precipitate with ammonium hydroxide. The amount of precipitate varied with the amount of lime used, the optimum being the point where the lime just begins to precipitate o r g a n i c matter from the liquor. This lime end point was later studied in detail by Leitz, Sivertz, and Kobe (4) who employed the glass electrode for p H determinations. In this work the Wulff indicator strip method was used. It was found that the maximum precipitate w i t h a m m o n i u m hydroxide was obtained when the liquor had a p H of 9.6. The relationships between pH and the weight of precipitate obtained with lime, and with ammonium hydroxide when the liquor is first brought to the indicated p H with lime, are shown in the figure. The percentage ash in the lime precipitate indicates the amount of organic matter in the precipitate. After determining the lime end point, all S. W. L. used was made alkaline t o this point with lime, and the P r e c i p i t a t e d calcium su1fit)e was separated from the liquor.
Ammoniation of
SULFITE WASTE LIQUOR When sulfite waste liquor is made alkaline with lime to a pH of 9.6, the free sulfur dioxide and part of the combined sulfur dioxide are precipitated as calcium sulfite. The resulting liquor can be directly ammoniated to give a solid and liquid portion, both of which contain combined nitrogen. The solid material is physically suitable for fertilizer.
KENNETH A. KOBE, JACK H. LAYMAN, AND FREDERICK R. ARMBRUSTER Department of Chemical Engineering, University of Washington, Seattle, Wash.
HORTLY after the announcement by Davis and Scholl (2) of the ammoniation of peat and its possible usefulness as a fertilizer, work was started on the ammoniation of sulfite waste liquor (S. W. L.). Their complete paper (6) mentioned the ammoniation of dried S. W. L. residue. Phillips, GOSS, Brown, and Reid (5) studied the ammoniation of dried S. W. L. residue by heating it with concentrated ammonium hydroxide at 200" and 220" C. for 4 to 20 hours, finding from 7.30 to 10.55per cent total nitrogen. They also found the ammoniated solid a beneficial fertilizer on a test millet crop. A German patent (5) claims the treatment of S.W.L. with ammonia and heating under pressure to 200" C. Peat or sawdust may be added to the S. W. L. This investigation had a different aspect from that of the other workers who had used a dried S. W. L. residue. The well-known difficulty of evaporating and drying S. W. L. makes this product difficult to obtain and greatly decreases the technical value of the previously described ammoniation processes. This work was started from the viewpoint of ammoniation of the concentrated S.W.L. obtained from the digesters. This liquor can be obtained with 10 to 12 per cent solids. The direct ammoniation of this material avoids evaporation, and therefore the continued study of this particular method was considered worth while.
Ammoniation Six liters of the alkaline S. W. L. were placed in an autoclave (I), and ammonia gas was passed in until the liquor was satu-
O S
o Weight
Precipitate From L i m e
A
Weight Precipitate From N%OH
0
Per Cent Ash in Lime Precipitate
Lime End Point First, it was observed that the addition of ammonium hydroxide to the concentrated S. W.L. gave only a minute amount of precipitate even when a great excess of ammonium hydroxide was used. It was concluded that the ammonium sulfite formed from the free sulfur dioxide must prevent pre-
pH o f Liquor 571
INDUSTRIAL AND ENGINEERING CHEMISTRY
572
TABLEI. RESULTSOF AMMONIATIOX Run No. Time
Initial NH3 Gage Pressure
Temp.
Per Cent N:! in: Residue Prefrom cipitate filtrates
Gage Pressure Ka./ (Lb./ Hr. SQ. cm. sq. in.) C. sq. cm. SQ. tn.) 1 20 0.35 0.35 0.43 2 20 0.54 .. 8.8 2 150 .. 15.5 .. 2.67 175 4.55 21.1 40 1:41 103 3.50 21.1 10 6120 5.66 10 2.81 82-105a 3 5 . 1 3.10 9.63 1.05 10 166 70.3 5.61 35,l 0.35 10 149 4.02 8 02 10 184 4.01 21.1 0.00 .. 4 Leak developed; temperature was increased from 82' to 105' C. t o maintain constant pressure
Kv./ W./
rated. The autoclave was connected directly to an ammonia tank so that the ammonia pressure in the liquid could be regulated up to the vapor pressure of liquid ammonia. The autoclave was rotated and the charge heated for a definite time, the pressure was released, the autoclave contents were removed, and the solids were separated. The filtrate was evaporated to dryness for a number of the runs. Nit,rogeii was determined in the precipitated solid and in the residue from the evaporated filtrate. The data are given in Table I. A material balance was made in run 8, all weights being calculated to a nitrogen-free basis. The initial lime treatment to the lime end point removed 4 per cent of the solids, and the ammoniation removed 69 per cent, leaving 27 per cent of the solids in the liquor. The precipitated solids analyzed 4.02
VOL. 28, NO. 5
per cent nitrogen, and the soluble material 8.02 per cent. Apparently the soluble carbohydrate material in the liquor ammoniated to a greater extent than the lignin, and remained in solution. Part of the material still in solution was precipitated by the addition of lime, so that a further recovery could be effected. However, the high nitrogen content of these dissolved solids required that all of this soluble material be recovered. The dried precipitated material is a very fine, dark brown powder which dusts easily. Although the nitrogen content of this material is not as high as that obtained from the evaporated S. W. L. (5),the use of higher temperatures and pressures may give equal values. However, the use of a precipitation method rather than an evaporation method to give a fertilizer material appears to be a great technical advantage. Pot fertilizer tests are being carried out by the Soils Section, Department of Agronomy, Washington State College.
Literature Cited (1) Beuschlein, W. L., and Conrad, F. H., Ed., 4, 415-17 (1932).
IND. ENG.CHEM.,Anal.
(2) Davis, R. 0. E., and Scholl, W., Science, 77, 330-1 (1933). (3) Franz, A., and Palm, A. (to I. G. Farbenindustrie), German Patent 561.487 (Feb. 18. 1930). (4) Leitz, C. F., Sivertz, V., and Kbbe, K. A., Pacific P u l p P a p e r I n d . , 9, No. 6 , 10-13 (1935).
( 5 ) Phillips, M., Goss, M. J., Brown, B. E., and Reid, F. R., J. Wash. Acad. S C ~ 24, . , 1-5 (1934). (6) Scholl, W., and Davis, R. 0. E., IND. ENG.CHEM.,25, 1074-8 (1933). RECEIVED December 20, 1935.
DER ALCHIMIST By Carl Duxa o In presenting No. 65 in the Berolzheimer Series of Alchemical and Historical Reproductions we express our appreciation to Mr. Benno Lowy, a member of the American Chemical Society in San Francisco, who kindly made arrangements for the photographing of the original painting which he purchased in Vienna a few years ago, and who gave Mr. Berolzheimer permission to publish this reproduction. Carl Duxa, the painter, was born in Vienna in 1 8 7 1 and studied at the Vienna Academy under Trenkwald from 1 8 8 8 t o 1 8 9 5 . I n 1 9 1 2 he was awarded the Dumba Prize of the Vienna Artists' Association. The original painting is 1 4 by 1 5 inches, and in its style and coloring resembles the work of Thomas Wijck, although some of the glass apparatus shown appears quite modern.
-4 detailed list of the first sixty reproductions, together with full particulars for obtaining photographic cropies of the originals, appeared in our issue for January, 1936, p?ge 129, where also will be found Reproduction N o . 61. Reproduction No. 6 2 appears on page 241 of our February issue, No. 6 3 on page 280 of March. and No. 6 4 on page 413 of April.
