Part 8 (2/2)
The following table, due to Mr WD Field, shows very plainly the great variation in the tiht causes It extends over fourteen working days, during which tiiven above, except that the specific gravity of the nitric acid is somewhat lower The product obtained differs only froravity 143 in being soluble in methyl-alcohol From 30 to 35 lbs of pyroxyline were produced in each of the fourteen days
A careful examination of this table will prove very instructive The increase in yield varies froh as 10 per cent, yet care was taken to make the product uniform in quality On the days it rained there was a loss, with the exception of the fourth day, when there was neither a loss nor a gain On the days it was partly clear, as just before or after rain, the table shows a loss in product We can explain this fact by reason of thequalities of the cotton On the rainy days it would absorb the moisture from the air until, when immersed in the acids, they eakened, and the fibre dissolvedwhat is known as ”burning” in the batch It will also be noticed that on days which show a loss, the tily short, as on the a loss, the tily short, as on the tenth, twelfth, and seventh days
______________________________________________________________________ | | | | | | Specific Gravity | Time | | |_____________________|_______________________________| | | | | | | | | | |H_{2}S0_{4}|HNO_{3}|Hours|Minutes|Hours|Minutes| |________________|____________|________|______|________|______|________| | | | | | | | | | 1 Clear | 1838 | 14249 || 20 | 4 || | 2 ” | 1837 | 14249 || 20 | 2 || | 3 Cloudy | 1837 | 14226 || 45 | 2 || | 4 Rain | 1837 | 1420 || 20 | 1 | 20 | | 5 Clear | 18377 | 142 | 1 | 15 | 2 || | 6 Rainy | 18391 | 1422 || 35 | 1 | 40 | | 7 Cloudy | 1835 | 14226 || 20 || 35 | | 8 Clear | 1835 | 1422 || 35 | 1 | 10 | | 9 Partly Clear| 1824 | 14271 || 20 | 1 || |10 ” | 183 | 14271 || 10 || 25 | |11 Cloudy | 1832 | 1425 || 10 || 50 | |12 Rainy | 1822 | 1425 || 10 || 20 | |13 Partly CLear| 18378 | 14257 || 60 | 1 | 40 | |14 Cloudy | 1837 | 14257 | 1 | 56 | 4 | 40 | |________________|____________|________|______|________|______|________| | | | | | |Tee | | |_______________|___________________| | | | | | | | | From | To | Increase | Loss | |________________|_______|_______|___________|_______| | | | | | | | 1 Clear | 57 | 62 | 31 || | 2 ” | 60 | 62 | 18 || | 3 Cloudy | 60 | 62 | 7 || | 4 Rain | 60 | 63 | 0 | 0 | | 5 Clear | 58 | 62 | 15 || | 6 Rainy | 58 | 62 || 2 | | 7 Cloudy | 62 | 65 || 10 | | 8 Clear | 60 | 62 | 5 || | 9 Partly Clear| 50 | 60 || 3 | |10 ” | 58 | 60 || 10 | |11 Cloudy | 58 | 60 | 8 || |12 Rainy | 58 | 60 || 10 | |13 Partly CLear| 50 | 58 | 20 || |14 Cloudy | 50 | 60 | 16 || |________________|_______|_______|___________|_______|
The lesson this table teaches is, that it is almost iet uniforh teards the solubility of pyroxyline, Parks found that nitro-benzene, aniline, glacial acetic acid, and camphor, dissolved in the more volatile solvents methyl-alcohol and alcohol-ether, werea plastic, as they are less volatile, and develop greater solvent action under the influence of heat Nitro-benzene gives a solution that is granular; it seems to merely convert the pyroxyline, and not to dissolve it; but on the addition of alcohol, a solution is at once obtained, and the granular appearance disappears, and the solution becoeneous The acidhave much to do with the action of the various solvents, so also has the presence of water
Dr Schupphaus found that propyl and isobutyl alcohols with camphor were active solvents, and the ketones, palmitone, and stearone in alcohol solution, also alpha- and beta-naphthol, with alcohol and anthraquinone (diphenylene diketone) in alcoholic solution, and also iso-valeric aldehyde and its derivatives, aust Sayer (USP, No 470,451) finds diethyl-ketone, dibutyl-ketone, di-pentyl-ketone, and the mixed ketones,[A] methyl-ethyl, methyl-propyl, methyl-butyl, methyl-amyl, and ethyl-butyl ketones are active solvents of pyroxyline; and Paget finds that although methyl-amyl oxide is a solvent, that ethyl-amyl oxide is not
[Footnote A: Ketones are derived from the fatty acids by the substitution of the hydroxyl of the latter by a monad positive radical They thus resemble aldehydes in constitution The best-known ketone is acetone CH_{3}COCH_{3} Mixed ketones are obtained by distilling together salts of two different fatty acids Thus potassic butyrate and potassic acetate form propyl-methyl-ketone--
C(C_{2}H_{5})H_{2} | COCH_{3}]
The solvents of pyroxyline can be divided into general classes--First, those which are solvents without the aid of heat or solution in alcohol; second, those that are solvents when dissolved in alcohol These solvents are those which also develop a solvent action when heated to theirpoint in coroups the solvents of pyroxyline into classes thus: Two of the monohydric alcohols; compound ethers of the fatty acids with monohydric alcohols, aldehydes; simple and mixed ketones of the fatty acid series These four classes include the greater number of the solvents of pyroxyline Those not included are as follows:--Amyl-nitrate and nitrite, methylene-di-methyl ether, ethidene-diethyl ether, amyl-chloracetate, nitro-benzene and di-nitro-benzene, coulacial acetic acid, and mono-, di-, and tri-acetin
Richard Hale uses the following solvent:--Amyl-acetate, 4 volumes; petroleum naphtha, 4 volumes; allon of solvent Hale used petroleu qualities of the varnish, so that it would set on the article to be varnished before it had a chance to run off It is, however, the non-hygroscopic character of the solvent that ely used for the production of pyroxyline varnish, which is used for varnishi+ng pens, pencils, &c, also brass-work and silver-ware
The body known as oxy-cellulose[A] is formed by the action of nitric acid upon cellulose when boiled with it The quantity formed is about 30 per cent of cellulose acted upon When washed free froelatinises
It is then soluble in dilute alkalies, and can be reprecipitated from solution by alcohol, acids, or saline solutions Messrs Cross and Bevan assign to it the formula C_{18}H_{26}O_{16} It dissolves in concentrated sulphuric acid, and with nitric acid forms a nitro body of the formula C_{18}H_{23}O_{16}3(NO_{2}), which is prepared as follows:--The gelatinous oxy-cellulose is washed with strong nitric acid until free froh asulphuric and nitric acids, in which it quickly dissolves The solution, after standing for about an hour, is poured in a fine streae volume of water, by which the ”nitro” body is precipitated as a white flocculentat 110 C, was found upon analysis to contain 648 per cent nitrogen
[Footnote A: ”On the Oxidation of Cellulose,” by CF Cross and EJ
Bevan, _Jour Chem Soc_, 1883, p 22]
MISCELLANEOUS NITRO-EXPLOSIVES
~Nitro-Starch~--It is only recently that, by esellschaft Dynamit nobel,” it has been possible toscale Nitro-starch has been known since 1883, when Braconnot discovered it, and called it xyloidine
Its formula is C_{6}H_{8}O_{3}(NO_{3})_{2}, but Dr Otto Muhlhausen has lately succeeded in preparing higher nitrated compounds, viz:--
(_a_) C_{6}H_{7-1/2}O_{2-1/2}(NO_{3})_{2-1/2}
(_b_) C_{6}H_{7}O_{4}(NO_{3})_{3}
Or doubling the en
i Tetra-nitro-starch C_{12}H_{16}O_{6}(ONO_{2})_{4} 1111 per cent
ii Penta-nitro-starch C_{12}H_{15}O_{5}(ONO_{2})_{5} 1275 ”
iii Hexa-nitro-starch C_{12}H_{14}O_{4}(ONO_{2})_{6} 1414 ”
He regards them as true ethers (esters) of nitric acid Thus on treatment with sulphuric acid, these co to be replaced by the sulphuric acid residue On treatment with a solution of ferrous chloride, nitric oxide and ”soluble” starch are regenerated On shaking with sulphuric acid over en is split off as NO
Tetra-nitro-starch is prepared upon the large scale as follows:--A quantity of potato-starch is taken and exposed in so apparatus at a temperature of 100 C until all the moisture which it contains is corinding, and dissolved in nitric acid of specific gravity 1501 The vessel in which this solution is accomplished is made of lead, and must be provided with two jackets, cooled by itator, in order to keep the nitric acid circulating freely The charge of starch is introduced through an opening in the cover of this digesting vessel, and the proportions of acid to starch are 10 kilogrammes of starch to 100 kilos of acid The temperature is kept within the limits 20 to 25 C When the solution of the starch is co apparatus, which is also provided with a cooling jacket, for the purpose of regulating the temperature The bottom of this vessel is double and perforated, and here is placed a layer of gun-cotton to act as a filter This vessel is filled with spent nitro-sulphuric acid obtained as a waste product frolycerine manufactory, and the solution of starch in nitric acid is sprayed into it through an injector worked by compressed air, whereby the nitro-starch is thron in the forrained powdery precipitate
In order to precipitate 100 kilos of the acid solution of starch, it is necessary to employ 500 kilos of spent nitro-sulphuric acid As it is precipitated the nitro-starch collects on the gun-cotton filter, and the acid liquor is run off through a tap placed beneath the perforated double bottom of the vessel, and of course below the filter pad The precipitated starch is further cleansed fros and by pressure, until all trace of acidity has been eliminated, and the substance exhibits a neutral reaction The next step is to treat the nitro-starch with a 5 per cent solution of soda, in contact hich it is allowed to stand for at least twenty-four hours The product is then ground up until a sort of ”milk” or emulsion is obtained, and lastly treated with a solution of aniline, so that when pressed into cake, it contains about 33 per cent of water, and 1 per cent of aniline
Dr Muhlhausen, working on these lines in the laboratory, prepared nitro- starch which contained 1096 and 1109 per cent of nitrogen When in the state of powder it is snohite in colour; it becomes electrified when rubbed; it is very stable, and soluble even in the cold in nitro- glycerine He has also prepared a tetra-nitro-starch containing 1058 and 1050 per cent of nitrogen, by pouring water into a solution of starch in nitric acid which had stood for several days The substance thus produced in the laboratory had all the properties of that prepared by the other process