1026
INDUSTRIAL AND ENGIYEERING CHEMISTRY
Gardner, H. A., Natl. Paint Varnish Lacquer Assoc., Sci. Sect. Circ. 507 (July, 1936). Ibid., 517 (Aug., 1936). Gardner, H. A., Paint Mfrs.’ Assoc. U. S.,Circ. 281 (Sept., 1926): Am. Paint Varnish Mfrs.’ Assoc., Sci. Sect., Circ. 317 (Oct., 1927), 347 (April, 1929), 351 (June, 1929), 361 (Feb., 1930), 363 (April, 1930),426, 427 (March, 1933),428 (April, 1933); Natl. Paint Varnish Lacquer Assoc., Sci. Sect., Circ. 480 (April, 1935), 489 (Sept., 1935); Special Circ. (Oct., 1935), 500 (Dec., 1935); Special Circ. (Jan., May, Nov., 1936). Gardner, H. A., “Physical and Chemical Examination of Paints, Varnishes, Lacquers and Colors,” 7th ed., p. 716 (1935). Ibid., pp. 1201-1448. Gardner, H. A., Butler, G., and Macnichol, C., Agr. Expt. Sta. N. Dak., Paint Bull. 1 (1910). Gehant, J. C., Paint Oil Chem. Rev., Dec. 24, 1936,7. Hagar, I. D.,Am. SOC.Testing Materials, Symposium o n Paint and Paint Materials, 1935,8 8 ; Ryan, L.W., Ibid., 99. Hallett, R. L., Ibid., 1935, 81. Hartwig, 0.R., Am. Paint Varnish Mfrs.’ Assoc., Sci. Sect., Circ. 355 (Aug., 1929).
VOL. 29, KO. 9
(24) Jacobson, A. E., Oficial Digest Federation Paint Varnish Production Clubs, 1935, 215. (25) Koffolt, J. H., and Withrow, J. R., Ohio State Univ. Eng. Expt. Sta., Circ. 32 (1936). (26) Ladd, E. F.,and Ware, E. E., Agr. Expt. Sta. N. Dak., Bull. 92, 174 (1911). (21) .MacGregor, J. R., Paint Oil Drug Rev., March 28, 1917; Am. Paint J., Nov. 28, 1927. (28) Natl. Lead Co.,Sat. Evening Post, June 23, 1934, 43; Aug. 24, 1935,77; Oct. 26, 1935,69; Am. Lumberman, Jan. 30, 1937, 13. (29) Nemzek, L. P.,Paint Mfrs.’ Assoc. U. S., Circ. 29 (Dec., 1914). (30) Paint Mfrs.’ Assoc. U. S., Sci. Sect., Bull. 16,17,19,25 (1909). (31) Rhodes, F.H., and Van Wirt, A. E., IND.ENG.CHEM.,15, 1135 (1923). (32) Robertson, D. W., Ibid., 28, 216 (1936). (33) Theobald, J., and Peters, R. L., Agr. Expt. Sta. N. Dab., Paint Bull. 2 (1910). (34) Walker, P.M . , Proc. Am. SOC.Testing Materials, 11, 225 (1911). RECEIIEIDJune 21, 1937. Presented before the meeting of the Paint and Varnish Production Club, New York, N. Y., September, 1936.
Effect of Lignin on Fermentation of Cellulosic Materials F. R. OLSON, W. H. PETERSON University of Wisconsin, containing this cellulose medium. Five transfers of the culture were made before any analytical work was begun; additional transfers did not seem to affect the fermentation products. This enrichment culture was used throughout the work except as otherwise indicated. Fermentations were set up in 500-cc. flasks-with 300 cc. of medium, 9 grams of cellulose or cellulosic material (which had been fluffed in a Williamson shredder), and 6 grams of calcium carbonate. Incubation took place a t 60” C., usually for a period of 7 days; cessation of gassing was taken as an index of completed fermentation. The chemical methods used were the same as those of Sarles, Fred, and Peterson (7). Table I gives the results of the fermentation of a number of pure or approximately pure cellulosic materials. These data are similar to those obtained in previous work (6-9). The average percentage of fermentation for six high-grade cellulosic materials was 88 per cent. The average decomposition of field-retted hemp fiber was 66.8 per cent. This reduction of decomposition may have been due t o the high lignin content for hemp fiber was found to contain 11.3 per cent lignin.
AND E. C . SHERRARD
U. S. Forest Products Laboratory, Madison, Wis.
T
HE fermentabilityof lignin or lignin-containingmaterials seems to be affected by a number of factors. Although there are many discrepancies in the literature, it appears that native lignin is more readily decomposed than the isolated material, that fungi are more active upon it than bacteria, and that aerobic conditions are more favorable than anaerobic for its fermentation. A review of the literature was given by Norman (5) who pointed out that some of the disagreements may have been due to the production of compounds which interfered with the subsequent lignin determinations. Recently several other papers (1, 4, 10) were published on various aspects of the problem. , thefermentabiliby of rice straw and other Acharya ( l ) studying natural materials by mesophilic organisms, found that the higher the lignin content of the substrate, the more resistant it was to decomposition, I n a previous- publication Peterson and Snies ~ k o(6) showed that wood pulps prepared by TABLE: I. FBRMENTATIOX OF CELLULOSE FROM VARIOUSSOURCES various methods exhibit great differences in --Volatile Acid fermenkability by thermophilic bacteria. Pure No, of Based on RepIi- Substrate total Compn. of Volatile Acid cellulose, on the other hand, is readily fermented Substrate cates Fermented Weight oellulose Acetic Butyric by such organisms and, under properly controlled % Grams % % % conditions, to approximately the same extent. Filter paper 20 72 0-96.1 3 84-5.97 42.6-66.4 52.5-94.0 6.0-47.5 -477. 90.6 5.18 57.5 56.0 44 0 Because Of these differences a further study was Rayon cellulose 4 Av.83.3-92 3.43-5.32 59.6-68.5 31.5-48.2 86.1 6 4.42 .38.1-59,1 49.2 60.6 39.4 made Of the fermentability Of cellulose and Alpha V cellulose 4 74.6-88.0 1.24-5 18 13.7-65.4 53.3-83.0 17.0-46.7 losic materials. Av. 83.9 4.10 45.5 62.0 38.0
--
Fermentation Procedure The medium used in this study was that described by Tetrault (9). Crude cultures were obtained by adding horse manure to test tubes
Burgess sulfite Linen Cotton Herup fibes
3
Av.
86 6-88 0
87.4 91.3 12 85.8-93.9 Av. 89 4 3 60.3-70 5 AT. 66.8 0
3.71-5.00 41.2-55 5 50.1 4.51 4.89 54.3 2.66-5 68 29.5-63.2 52 6 4 74 188-3.63 20.9-39.2 2 76 30.6
57.0-72.0 43.0-28.0 30.3 69.7 68.9 31.3 32.0-72.5 27.6-68 0 33.7 66.3 67.3-71.1 28 9-32.7 69.2 30.8
SEI'I'EMBER, 19.17
INDUSTRIAL AND EYGIYEERING CHEMISTRY ~
Enrichment cultures of thermophilic organisms which readily ferment pure cellulose are easily obtained. These cultures do not ferment groundwood (extractive-free and ball-milled) either alone or in the presence of filter paper. Holocellulose prepared from a number of woods was readily fermented. When added to a medium containing free cellulose, lignin or lignin-containing material-. g., groundwood-did not inhibit the fermentation of cellulose. The lignin was not destroyed in such fermentations and was recovered in the unfermented residue. The nonfennentability of wood was found to be associated with its lignin content. In order to obtain a good fermentation (85 per cent destruction), the lignin content had to be less t h a n ' l per cent. These results and those obtained by fine grinding suggest that the relation between the lignin and carbohydrates is chemical and not merely physical.
Variations in the decomposition of filter pa.per indicated that there were two t y p e s of enrichment cultures. One produced a rnther good ntilizatiom of subfitrate (82 t o 95 per cent); the other ferinented onlyabout 72 per cent of the total. The more vigorous culture produced a large a m o u n t of butyric acid, whereas tile less vigorous one produced mainly acetic and but little butyric. The Former was used in most of the experiments.
Fermentation of Groundwoods Samples of white spruce, sr1ga.r m a p l e , vhite oak, white birch, and loblolly pine were ground to sawdust~, a n d t h o m a t e r i a l which passed a 60-mesh but was retained by an SOmesh screen was used for frrinentation. To remove cstmctives, t h e sawdilst,
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was extracted continuonsly with an alcohol-benzeene solrltion (1 to 2) for 24 hours and then thoroughly washed with hot water. None of these materials gave any indication of fermentation over a 20-day incubation period. It was thought that, if the material were first ground in a ball mill, more of its cellulose would be exposed to bacterial action, but a number of white spruce samples ground for 100 hours did not ferment.
I. IARLE 11.
5 E.
S~XUW.
FERMENTAT~OK OF MIXTURESOF FILTER frmn AND GROUNDWOOD
Liawdun!
6 il. s ~ i u e e .hall-mill ground 8 a. filter p w e i 3 &. spzuce (NnOH-treated)
+
+ 3 e. G l t e i ~ a p e r+ S g. xpruoe (extraotivs-iiee)
3 g. filter paper 3 g. SPrUOe (HzSO*-treated)
0.27 0.07 2.89 3.12
2.70
* Rased on total subrcrate. b
Based on weight of filter paper.
Two explanations are indicated: Either a toxic substance is present in extractive-free wood, or the carbohydrates and lignin exist in such a physical or chemical state that the organisms cannot attack tlie cellulose. To test the first possibility, filter paper and extractive-free spruce were groniid together in a ball mill, and the mixture vas used as a substrate. That
INDUSTIiIAI, AND ENGINEGKING CtIEMISTIlY
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OF HOL~CELLULOSE AND EFFECTOF TABLE 111. FERMENIATION ISOLATED LIGXINON FERME~PPATION O F FILTERPAPER
Voistile Based Acidvu total Fermented Weiqht substrate Substrate
Rubstrato
%
spriiee iloiooeiiuiDse 86.8 O M*p~eliol'Jeellul"vl B I h"l"cellsi
