The Chemical Evaluation of Wood for Pulp. - Industrial & Engineering

1914 6 (7), pp 556–560. Abstract | Hi-Res PDF · Determination of Carbon in Soils and Soil Extracts. Journal of Industrial & Engineering Chemistry. A...
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T H E J O U R N A L OF I N D U S T R I A L A N D ENGINEERING C H E M I S T R Y

560

Vol. 6, KO. 7

last t w o determinations t h e titration was made in t h e presence of both P b a n d Cu salts.

valuation according t o t h e amount of fiber wood will yield, which is t h e chief concern of manufacturers of chemical pulps. Wt. of Wt. of S b W t . of S b Error present found percentage Number of sample T o make effective a n y of these units as a basis for Gram Gram composition experiment Gram evaluating wood for pulp we must resort t o a n efficient (1) . . . . . . . . . . . . . . . . . 0.3000 0.0350 0.0349 O0.0370 ( 2 ) . . . . . . . . . . . . . . . . . 0.3000 0.0350 0.0349 O0.0370 system of sampling which will be truly representative. 0.0350 0.0349 U0.0370 (1) . . . . . . . . . . . . . . . . . 0.3000 0.0350 0.0359 ( Z ) . , . . . . . . . . . . . . . . . 0.3000 00.0370 Such a system was described in t h e author's former 0.0353 (3) . . . . . . . . . . . . . . . . . 0,3027 0.0354 00.037, 0.9353 (4) ................. 0.3027 0.0356 00.09% paper. (1) . . . . . . . . . . . . . . . . . 0 0327 0.0353 0.0354 00.03% T h e need of such a basis for valuing wood is a t once ( Z ) , . . . . . . . . . . . . . . . . O:d327 0.0353 0.0354 00.03% apparent when we stop t o think of the great variation T h e above results indicate t h a t the presence of t h e in t h e quality of t h e same species, depending upon P b a n d Cu salts do not interfere with t h e titration of its habit a n d conditions of growth. Poplars of our S b with KhinO4. northern states differ greatly from those of the middle S E R I E S V-ZINC southern states. The measurement of value by cord Wt. of W t . of Zn Wt. of Zn Error or solid contents takes n o account of yield in pulp. sample present found percentage Number of Gram Gram Gram experiment composition Other species of similar external characteristics are (1) . . . . . . . . . . . . . . . . . 0.4985 0.1497 0.1492 O0.1070 often mixed in, as Bass wood with poplar, and fir ( 2 ) . . . . . . . . . . . . . . . . . 0.4969 0.1492 0.1497 O0.1170 0.1494 0.1497 00.0670 ( 3 ) , . . . . . . . . . . . . . . . . 0.4975 a n d hemlock with spruce. Such mixtures in late 0.1494 ( 4 ) . . . . . . . . . . . . . . . . . 0.4977 0.1495 O0.0Z70 0.1495 0.1496 ( S ) . . . . . . . . . . . . . . . . . 9.4979 00.029 years have been permitted, when t h e characteristics ( 6 ) . . . . . . . . . . . . . . . . . 0.5004 0.1503 0.1505 00.048 are near enough t o cause no trouble in cooking. Aside P A R T 111-SUMMARY from these differences in species, a n d habit of growth, I-A survey of a large number of proposed methods there is t h e quality of t h e wood, as such, which should for t h e analysis of bronze a n d brass has been made.. be t a k e n into account in its bearing on yield of pulp. T h e majority of t h e methods have been found t o be Wood is subject t o disease a n d decay a n d all such too long a n d elaborate; or if in t h e class of rapid meth- defective wood will not give t h e normal prqduct. ods, too inaccurate t o be suitable even for control With a view t o discovering t h e influence of these work. various factors upon t h e yield, a large number of de11-A method has been proposed for the analysis terminations of t h e cellulose were made b y t h e Cross of bronze a n d brass containing Pb, Cu, Sn, Sb, Fe, a n d a n d Bevan chlorination method. Zn b y which t h e determinations may be made with PROCEDURE-The stick t o be tested was quarter greater rapidity t h a n a n y other methods of analysis sawn, a n d the sample was obtained b y planing thin known t o t h e authors. Working with t h e usual lab- shavings from t h e face of t h e quarter. I n this way oratory facilities i t has been found t h a t after the sam- t h e sample would include a part of t h e growth from ples have been weighed t h e determinations of Pb, t h e center t o t h e bark. We found such thin s h a ~ i n g s Sn a n d S b in three different alloys can be easily com- much more satisfactory t h a n a n y other form. Three pleted in one a n d one-half t o two hours. grams of the shavings, previously dried a t 100' C., 111-The determinations made by this method not were boiled for about half a n hour in I per cent sodium only agreed among themselves b u t they were more hydrate. T h e mass was then well washed a n d squeezed accurate t h a n those made b y t h e longer methods. a n d placed under a bell-glass, into which was led T h e maximum error of a n y determination in a n y series a slow stream of chlorine gas. Complete conversion was 0.1j per cent. T h e average error, however, is of the lignone usually followed in one hour's exposure much less. t o t h e gas. It was then well washed t o remove hydroIV-The accuracy a n d general applicability of t h e chloric acid a n d impurities a n d placed in a two per cent proposed method has been shown by t h e series of test solution of sodium sulfite containing 0.2 per cent experiments, a n d further confirmed b y t h e report of sodium hydrate, a n d boiled for a b o u t five minutes. one commercial laboratory where the method has been T h e fiber was then well washed with hot water and constantly employed for nearly three months. this treatment with sodium sulfite a n d hydrate reCHEMICAL LABORATORY, ALLEGHENY COLLEGE peated if found necessary. T h e fiber was found MEADVILLE, PA. almost pure a n d nearly white.' It was then dried, weighed a n d results calculated. Table I gives t h e characteristics of 24 samples of THE CHEMICAL EVALUATION OF WOOD FOR PULP' B y M . L. GRIFFIN mixed spruce a n d brilsam fir from Montmorency in I n a previous paper,* t h e author showed t h e inade- Canada. T h e samples were selected t o show t h e quacy of t h e cord 'measure as a unit for valuing pulp various factors influencing t h e yield in chemical fiber. wood, resulting in great variation in t h e solid volume, Eight of these samples were chosen from wood of recogdue t o various factors. As a better standard he nized good quality for comparison. F r o m a review advocated a solid unit, the cubic foot, a n d illustrated of t h e table a n d t h e samples we observe: I-That density of annual ring growth is not neceshow such a unit could be adapted in practice without inconvenience. A unit of weight as a still more re- sarily proportional t o specific gravity (see N o s . I , liable basis was also advocated. There remains the 7, 9, 23 a n d 24) a n d t h a t specific gravity is not pro1

1914.

Presented before the Maine Section of t h e A. C. S.. Auburn, M a y 1,

* See abstract,

THIS.JOURNAL,6, 163.

1 T o remove t h e last residues of non-cellulosic matter, it may be bleached with hypochlorite or permanganate. I f with the latter, i t will be necessary t o wash with a weak solution of sulfurous gas.

T H E J O C R X A L O F I N D G S T R I A L A N D ENGINEERIiL'G C H E M I S T R Y

July, 1914

portional t o yield of fiber. This latter is also shown b y Nos. 2 , 8, 2 1 a n d 22, where yield is fairly regular a n d specific gravity is irregular. This would indicate t h a t habit a n d environment have much t o d o with t h e quality of wood. 11-We can establish very well t h e influence of incipient decay upon t h e yield b y comparing Kos. 1 2 , 1 7 a n d IS, all of which are sound specimens, with h-os. j, 4, j a n d ti; t h e annual ring growths compare

j61

averages about 48 or 7 5 per cent, showing t h a t t h e voids in 2 feet wood are less t h a n in 4 feet wood. Comparing t h e solid cubic feet we find i t t o be about I O O in t h e case of 2 feet wood a n d 9 j in 4 feet wood. From experiments not shown here, i t has been proven t h a t large wood contains more solid wood per cord t h a n small sizes, in t h e ratio of about 96 t o 9 2 . From these results i t is apparent how important i t is t o t h e manufacturer of chemical pulp t o know

TABLEI - ~ I O N T M O R E N CWOOD Y TEST(NOVEMBER. 19 12)

S O .

1 2 3

8 9

10

11 12 13 14 15 16 17 18

1Y 20 21 22 23 24

Sp. gr. of wood Rings per dried a t DESCRIPTIOS OF S A M P L E Diameter inch 100' C. 2 FT. \VOOD-lO0.3 SOLID FT. PER C O R D Sound, fine g r a i n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10" 23.3 0.4700 Sound, fine g r a i n . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 21.4 0.3522 Dead wood, medium coarse.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SI/? 14.1 0.3697 of center dry rot well established.. . . . . . . . . . . 13.1 0.3535 of center d r y rot, p o o r . . . . . . . . . . . . . . . . . . . . . 15.6 0.3518 of center dry rot, very p o o r . . . . . . . . . . . . 15.4 0.3474 ne grain, slight indication of dry rot surfa 24.4 0.4141 .................................... 19.2 0,3076 6.8 0.3475 Sound, very coarse g r a i n . , . . . . . . . . . . . . . . . . 10.7 0.3365 Coarse grain, slight indication of dry rot su Sound . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.7 0.3242 Coarse grain, s o u n d . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16.2 0.3166 16.3 0,3469 D r y rot and dead throughout, poor. . . . . . . . . . . . . . . . . . . . . . . . Coarse grain, dry rot well established throughout.. . . . . . . . . 5 ?/iz 10.2 0,3242 Coarse grain, s o u n d . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 12.0 0.4094 5 12.5 0,3347 Coarse grain, dead wormy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 F T . \VOOD-95.64. SOLID FT. PER CORD l l e d i u m fine grain, s o u n d . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5l!, 15.3 0.4011 Coarse irregular grain, dense, s o u n d . . . . . . . . . . . . . . . . . . . . . . 8112 12.9 0,4333 Coarse grain, rather light, s o u n d . . . . . . . . . . . . . . . . . . . . . . . . . . SI/, 12.0 0.3556 Coarse grain, s o u n d . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 12.0 0.4291 Fine grain, s o u n d , , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . il/z 19.7 0.3597 Irregular grain, medium dense, s o u n d . . . . . . . . . . . . . . . . . . . . 7 18.2 0.3651 Very fine grain. dense, s o u n d , , . . . . . . . . . . . . . . . . . . . . . . . . . . 101/z 24.0 0.3391 Very fine grain, light s o u n d . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 23.0 0.3368

favorably a n d yet t h e specific gravities a n d yields of t h e latter are noticeably low. 111-The most important conclusion of all a n d t h e one we are perfectly safe i n drawing is t h a t there is great variation in t h e yield of chemical pulp a n d t h a t some consideration should be given t o this yield i n fiber in valuing wood for pulp. T h e yield per cord is found b y taking t h e solid volume which the author has found t o be about I O O CU. f t . a n d multiplying b y . t h e specific gravity. This gives t h e cord veight basis from which t h e yield i n fiber can be calculated. The volume yield is found b y multiplying t h e specific gravity into t h e percentage fiber yield. T h e specific gravity of wood is very quickly determined approximately b y displacement in mercury instead of water.

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T h B L E 11-MONTMORENCY WOOD

TEST (NOVEMBER,1912)

lveight of Area in one cord one cord Lbs. Moisture +--Actual Per cent per cent W-et Dry sq. f t . total 2 FT. WOOD 40.1 3990 2392 ... ... 43.3 3992 2220 .., ... 38.4 3636 2240 49.4 77.2 38.4 3616 2228 48.5 74.8 48.5 4395 2140 51.65 80.8 48.. 4255 2075 51.15 79.8 24 44 31 00

3014 3313

2277 2286

4 FT WOOD 24.22 75 70 23.60 73 75

Volume in one cord

Actual cu. ft.

.. 9i:S 97.0 103.3 102.3

No. of Per cent sticks in total

one cord

. . . . . .

. . . . . . 77.2 74.8

80.8 79.8

178 185 210 184

YIELD I

Per cent by weight

Per cent b y volume

Lbs. per per cord

51.6 51.5 49.5 47.2 52.3 48.2 52.8 53.5 55.2 54.1 53.9 52. I 41.6 4:. 2 54.0 49.2

24.2 18.1 18.3 16.7 18.5 16.7 21.9 16.4 19.0 18.2 17.5 16.4 14.4 15.3 22.1 16.5

1515 1132 1144 1045 1157 1045 1370 1026 1189 1139 1095 1032 901 957 1383 1032

55.0 54.5 56.1 57.2 53.0 51.6 57.5 59.0

22.1 23.6 19.9 24.5 19.1 18.8 19.5 19.9

1383 1477 1245 1533 1195 1177 1220 1245

what his wood will yield a n d for his purposes i t should be valued accordingly. Progress in valuing wood in a n y other way t h a n b y t h e cord unit mill be slow, because all timber having a dimension lumber value will necessarily be valued b y dimension. Again, as wood finds various markets, i t will be valued according t o t h e use i t is p u t t o in t h e highest market a n d t h e tendency t o value all wood b y t h e unit measurement of t h e principal market will persist. hIeanwhile conditions are rapidly changing whereby t h e poorer grades of wood only are finding their way t o t h e pulp mills a n d t h e question of supply a n d demand are determining factors. So far as t h e author knows, manufacturers of pulp have done little or nothing t o promote a better standard of valuing wood for their uses a n d we may expect no change until t h e y t a k e this matter more seriously in t h e interest of more efficient management of their plants. RUMFORD, MAIKE

DETERMINATION OF CARBON IN SOILS AND SOIL EXTRACTS By J. W. AXES

AND

E. W. GAITHBR

Received April 6, 1914 96 88 94 40

i5.70 73.75

80 109

Table I1 shows t h e weights per cord of mixed spruce a n d balsam fir containing different percentages of

moisture and t h e dry weight, which averages about 2 2 0 0 lbs., free from moisture. Comparing t h e square foot cross-section of a cord of 2 feet a n d 4 feet woods, we observe t h a t t h e former averages about 50, or 7 8 per cent, while t h e latter

T h e method of estimating total carbon i n soils by oxidation with a mixture of chromic a n d sulfuric acids has been tested b y different chemists with varying results, Warrington a n d Peakel found t h a t t h e chromic acid method gave lower results t h a n those obtained b y combustion in current of oxygen. Later, Cameron a n d Breazeale2 compared t h e chromic acid 1 1

Jour. Chem. Soc.. 37 (1880),617 Jour. A m . Ckem. Soc.. 26, 29.