I N D U S T R I A L A N D E,VGINEERING CHEMISTRY
July, 1920
IXORGAYIC C o ~ ~ o u s ~ s - -few A of the inorganic nitrates and chlorides are soluble in 1,4-dioxan, but the greater majority of the inorganic chemicals are only partially soluble, or insoluble. Commercial Application The solvent action of 1,4-diouan obviously suggests its use as a solvent in the rrmnufacture of various types of lacquers, celluloid, and similar prodiicts where nitrocellulose. cellulose acetate, or other cellulosic esters or ethers are used. It is of value as a netting agent in the treatment of fibrous materials that are not easilv wet with water. Being a solTrentfor fats,
697
the preparation of varnishes, polishing compositions, paint and varnish removers, detergent and cleaning preparations, toilet preparations and cosmetics, cements, glues, shoe creams, emulsions, etc. It has also been suggested for use as a preservative, fumigant, or deodorant. Literature Cited (1) Anschutz and Broeker, ~ e r 59B, , 2844 (1926). ( 2 ) Clarke, J . Chem Soc., 101, 1789 (1912) (3) Da"idson, IVD B "1 669 (4) Fanorski, J . Russ Phys Chem S o c , 3 8 , 741 (1906) ( 5 ) Ghosh, Chem ljs9 (lolj) ( 6 ) Lourenzo A X X c h t m 131 67. 268 (1863)
Influence of Acids upon the Fixation of Wattle Tannin by Hide Powder'" Arthur W. Thomas and Margaret W. Kelly DEPARTMENT OF CHEMISTRY.COLUMBIA UNIVERSITY, XEW YORK,N. Y.
I
K PREVIOUS publications (3)* on effect ofipHivalue upon
the fixation of vegetable tannin by hide substance, the reagent used to adjust the tanning solutions to acid pH values was generally hydrochloric acid. While Loeb ( 1 ) showed that the properties of proteins varied according to the pH values of the solutions with but slight, if any, differences resulting from the nature of the acid or base uwd to'create a given pH value, it was considered interesting to study the fixation of a vegetable tannin a t pH values effected by different organic acids. It has alreadv been shown that formic acid produces a different effect "upon vegetable tannin solutions than hydrochloric acid ( 2 ) .
pon-der. These mixtures were then agitated in a tumbling machine a t room temperature for 6 (or 24) hours, when they were filtered in T17ilson-Kern extractors. I n every case a positive gelatin-salt test was obtained, showing that the tannin content of the solutions was not exhausted. The tanned hide powders were thoroughly washed with distilled water as judged by the ferric ion test. They mere then airdried, removed from the extractors to weighing bottles, and dried for 16 hours a t 100" C. in a vacuum oven. The increases in weight were taken as "tannin fixed" bv the hide Dowders.
hiaterials The hide powder, American standard, was first extracted with chloroform to remove fatty matter and sifted on a 100-mesh screen to remove fine particles. The tannin employed was commercial wattle bark extract. The acids employed were chemically pure specimens. Method Portions of hide powder equal t o 2.000 grams of moisture-free material were placed 0.501 1 8.0 8.5 3.0 3.5 4.0 in 450-cc. rubber-stoppered bottles and alpH of Tanning Solution pH of 3 m i n g solution lowed t o soak in 50-cc. portions of distilled Figure 1-Time of Tannage, 6 Hours Figure 2-Time of Tannage, 24 Hours water for 1 hour. Then 350-cc. portions of pH a n d N a t u r e of Acid Present. N u m b e r s Refer wattle bark solution were added, T~ these Fixation of Tannin as a F u n c t i o ntoofAcids in T a b l e I1 tannin solutions there had been previously Results added sufficient quantities of the various acids to yield the desired pH values after contact with the moist hide powder. The quantitative results are recorded in Table I and in The concentration of tanning agent was such as to provide a Figures and 2. It will be noted that the degree of tannin "total solids" of tanning material equal to 40 grams per liter fixation from the untreated wattle solut~onsis not constant, when diluted with the water already in contact with the hide This is due partly to slight variations in the ~ l pH 1 Presented before the Division of Leather and Gelatin Chemistry value of these solutions, but mainly to differences in room a t the 76th Meeting of the American Chemical Society, Swimpscott, Mass., temperature, the measurements having been carried out Over September 10 to 14, 1928. a period of several weeks. 1 Contribution from the Department of Chemistry, Columbia UniFigures 1 and 2 demonstrate that in both the 6- and 24-hour versity, No. 599. * Italic numbers in parenthesis refer to literature cited a t end of article. tanning periods the fixation Of tannin a t a given pH value varies I
~
698
I-VDUSTRIAL A S D ENGINEERING CHEMISTRY
Table I-Fixation of W a t t l e T a n n i n i n Presence of Diverse Acids PHOF TANNIN PHOF TANHIN ADDEDTANNING FIXED BY ADDEDTANNING FIXED BY PRESENT ACID SOLUTION 2 SUBSTANCB GRAMSHIDE ~ & + ~
p&i&2:;-
6 Hrs. 24 Hrs. Grams Grams
Mols per liter
liler
ACETIC ACID
None 0.006 0.059 0.319 1.260 4.770
4.67 4.15 3.69 2.92 2.49 1.86
0.67 0.70 0.95 1.27 1.59 1.57
4.50 4.00 3.41 2.9s 2.44 1.96
0.58 0.66 0.80 1.12 1.29 1.66
0.82 0.90 1.39 1.56 1.93 1.80
h-one 4.77 0.0020b 4 . 2 4 0.0054b 3 . 5 7 0.013b 3.05 0.0430 2 . 4 8 0.1319 2 . 0 3
0.78 0.83 1.28 1.53 1.81 1.99
None
0.0022a 0.00480 0.00760 0.0133d 0.0222d
4.62 4.00 3.53 3.00 2.45 2.10
0.53 0.57 0.73 0.91 1.27 1.58
0.69 0.87 1.05 1.24 1.72 1.86
None 0.0025 0.0087a 0.017” 0.042b 0.127b
4.60 3.88 3.35 2.90 2.47
None 0.003a 0.007a
4.65 4.06 3.78 3.07 2,57 1.99
...
... ... .. ..
0.064a 0.254a
4.63 3.99 3.44 2.98 2.40 2.10
0.62 0.68 0.80 0.90 1.10 1.19
4.85 4.38 3.53 3.01 2.47 2.05
HYDROCHLORIC
0.73 0.87 1.23 1.48 1.74
CITRIC ACID
0.59 0.63 0.66 0.92 1.12 1.44
0.77 0.90 0.98 1.09 1.58 1.51 0.87 0.98 1.01 1.23 1.39 1.77
MONOCHLOROACETIC ACID
SUCCINIC ACID
None 0.008 0.031 0.09;.
0.62 0.63 0.88 0.96 1.26 1.37
OXALIC ACID
FORMIC ACID
Kone 0.004 0.013 0.031 0.166 0.425
24 Hrs. Grams
TARTARIC APTn .~~~ .~~~ ~.
LACTIC ACID
None 0.004b 0.013b 0.048b 0.092b 0.395b
6 Hrs. Grams
Mols per
0.86 1.03 1: il 1.57 1.71
. ,. ., .. ,
,.
..
0.65 0.70 0.85 1.17 1.40 1.61
ACID
None 4.85 0.59 0.71 0.0035 4 . 0 0 0.68 0.75 0.0075’ 3 . 2 3 0 70 0.93 0.0097a 2 . 9 1 0.90 1.04 0 . 0 1 4 ~ 2.41 1.24 1.21 0 . 0 2 4 ~ 1.90 1.22 1.48 Tanning solution was slightly turbid. b Tanning solution was decidedly turbid. c Tanning solution contained slight precipitate. d Tanning solution contained moderate amount of precipitate.
Vol. 21, No. 7
with the nature of the acids used. Taking the p~ range of 2.5 to 3.0, the order of tanning intensity is as given in Table 11, together ~ ~ with ~ the E strengths of the acids. Table 11-Order 6 - H o u ~TANNAGE
of Influence u p o n T a n n i n Fixation 2 4 - H o u ~TANNAGE
Acetic Lactic Formic Tartaric, citric Oxalic Hydrochloric
Acetic Lactjc Succinic Formic Citric Tartaric Oxalic Monochloroacetic Hydrochloric
INVERSBORDEROF ACIDSACCORDING TO DISSOCIATION CONSTANTS 1-Acetic 2-Succinic 3-Lactic 4-Formic 5-Citric &Tartaric. - -. .-.-
7-Monochloroacetic 8-Oxalic 9-Hydrochloric
Table I1 shows, within the limits of acids studied, that the order of tannin fixation a t a given pH value qualitatively is very closely inversely proportional t o the dissociation constants of the acids. Acknowledgment
The authors thank the A. F. Gallun & Sons Corporation, of Milwaukee, for grants in aid of this investigation. Literature Cited (1) I,oeb, “Proteins and the Theory of Colloidal Behavior,” McGraw-Hill Book Co.. New York. 1924. (2) Thomas and Foster, IND. ENG.CHEX.,15, 707 (1923). (3) Thomas and Kelly, Zbid., 15, 1148 (1923); 16, 800 (1924).
Syntan Tannage’s’ Arthur W. Thomas and Margaret W. Kelly DEPARTYENT O F CHEMISTRY, COLUMBIA UNIVERSITY, N E W YORK,N . Y.
HE name “syntans,” a contraction of the words “syn- as a function of the acidity conferred upon tan liquors by thetic tannins,,’ is applied to sulfonated aldehyde con- these strongly acid products has been found. It was theredensation products of hydroxyaromatic compounds fore considered timely t o start such an investigation. This which have tanning action, although chemically they do paper records data on the action of the combination of a synnot resemble the natural vegetable tannins. tan with each of two astringent vegetable extracts, queAs early as 1875 a product with tanning properties was bracho and wattle. The syntan used was an American prodprepared by Schiff (1)* by the action of phosphorus oxychloride uct known as “ L e ~ k a n o l . ’ ~ ~ Analysis of this syntan by the method recommended by upon phenolsulfonic acid, but the first process for the commercial manufacture of a syntan of technical value was Kohn, Breedis, and Crede ( 2 ) gave a total solids (corrected for introduced in 1912 by Stiasny. This product, known as alkali added in the determination) and an ash content of 361 Neradol, and other competing products of similar nature and 222 grams per liter, respectively. Concentrated stock solutions of wattIe and quebracho were extensively used in the Central Empires during the war owing to isolation from sources of vegetable tanning extracts. extracts were prepared by dissolving the dry extract in hot Syntans are not satisfactory tanning agents when used water and allowing t o stand overnight, after which the mixalone, one reason being their hydrolytic action on hide sub- tures were centrifuged and the supernatant liquid filtered by stance, but are claimed to be valuable adjuncts t o vegetable suction through filter paper. Total solids determinations tannins. Possessing lower molecular weight, they diffuse were made on these final solutions by the A. L. C. A. method. into the hide more rapidly than natural tannins. They Experimental Procedure have the property of rendering soluble the difficultly soluble components of certain vegetable tanning extracts and of Samples of defatted hide powder equivalent t o 2.000 grams, inhibiting mold growth. Syntans evert a bleaching action on vegetable-tanned leather and are used also for this reason. absolutely dry weight, were tanned in 200-cc. portions of Several general papers on the merits of the combination tanning solution for 24 hours unless otherwise indicated. of syntans with natural tannins in the production of leather Samples were then filtered in Wilson and Kern extractors and are in the literature, but as yet none comparing the effects washed for 24 hours with distilled water, when a negative test was always obtained for the various components of the 1 Presented b y A W Thomas before the Division of Leather and tanning solution employed. After air-drying, the tanned Gelatin Chemistry at the 74th Meeting of the American Chemical Society, samples were transferred t o weighing bottles and dried for Detroit, Mich , September 5 to 10, 1927 Received March 2, 1929 16 hours a t 100” C. in a vacuum oven. The increase in dry 2 Contribution from the Chemical Laboratories, Columbia University,
T
No. 601. Italic numbers in parenthesis refer to literature cited at end of article.
*
a Kindly furnished by the Rohm and Haas Company.
