BRITISH CHEMICAL ABSTRACTS
B.—APPLIED CHEMISTRY
A U G . 19, 1927.
I.-G E N E R A L ; PLANT; MACHINERY.
Micro-analytical practice in the works. A. Me ix-
n e r and F. Kr o c k e r (Mikrochem., 1927, 5,120—133).—
A brief description of the methods used by the authors in the micro-analysis of organic compounds for carbon, hydrogen, nitrogen, chlorine, sulphur, selenium, arsenic, phosphorus, vanadium, and mercury by means of the Pregl combustion apparatus, together with details of the necessary precautions to be taken to obtain accurate results. For the determination of mercury in organic compounds the substance is burnt in a current of oxygen in a small combustion tube, and the issuing gases are passed through red-hot lime and then over a small coil of gold leaf to collect the mercury. A. E. Po w e l l.
Determination of m oisture by the volatile solvent method. J . M . J o n e s and T . M c L a c h l a n (Analyst, 1927, 52, 383—387).—A critical examination of the volatile solvent method for determining moisture shows that, whatever solvent is used, distillation must be con
tinued until no further water distils, and as water of hydration is reiyoved, even with benzene, this must be allowed for. Toluene is regarded as the most generally useful solvent, and the method is particularly recom
mended for emulsions, including butter and oils, but not for powders etc. which do not cake. Consistent results were obtained with jams, malt extracts, etc.
D. 6 . He w e r.
Apparatus for gas analysis. J. N. J. P e r q u i n
(Chem. Weekblad, 1927, 24, 321—325).—An apparatus for exact analysis, arranged so that no connexions with rubber tubing are necessary to introduce either gases or absorbents, and in which all the parts are permanently joined, is described. The ordinary quartz combustion tube is replaced by one of nickel, and movements of mercury for levelling, moving the gases, etc. are effected by compressed air and water, electrically controlled.
The error due to the absorption of carbon dioxide by copper oxide on cooling after a combustion, which affects the results obtained in the ordinary method, may be eliminated by sweeping out the combustion tube, while still at a red heat, with oxygen generated elec
trically within the apparatus; the carbon dioxide is absorbed in the burette by means of potassium hydroxide, and the oxygen by means of hyposulphite. The com
bustion tube is then ready for a further determination.
S. I. Le v y.
Gas analysis instrument based on sound-velocity m easurem ent. E. Gr i f f i t h s(Proc. Physical Soc., 1927, 39,300—304).—A form of gas analysis apparatus utilising stationary waves produced by a quartz crystal set into vibration piezo-electrically is described. The deter
mination is based upon a measurement of the wave-length of the waves so produced, the instrument being more especially applicable to binary mixtures of gases, e.g., air and carbon dioxide, which do not react.
J. S. G. Th o m a s.
Gas analysis apparatus. Fr e d e r ic k.— S ee VII.
Pa t e n t s.
Mixing machines. J. Fo w l e r & Co. (Le e d s), Lt d., and C. H . Fo w l e r (E.P. 272,151, 17.5.27).—To prevent any tendency to “ balling ” of the material in a rotary mixing drum, spherical projections or inden
tations extending inwards are provided. These are preferably equally spaced and located near the junction of the base and the side wall. H . Ho l m e s.
Increasing the weight per unit volume of pul
verulent heaped m aterial. A. L . Mo n d. F r o m I. G.
Fa r b e n in d. A.-G. (E.P. 272,109, 13.12.26).—A c r y s ta l
lin e p r o d u c t , e s p e c ia lly o n e o b ta in e d b y d r y in g o r c a lc in a tio n t o re m o v e w a te r o f c r y s ta llis a tio n o r o th e r v o la tile c o n s t it u e n t, is g ro u n d u n d e r p re s s u re , e.g., in a n e d g e -r u n n e r m ill, th e r e b y c o m p re ssin g a n d c o m p a c tin g t h e c r y s t a l s k e le to n s a n d , a d d itio n a lly in so m e cases, b r e a k in g u p t h e sk e le to n s . H . Ho l m e s.
Filtering device. W. B. Pu m p h r e y (U.S.P.
1,633,604, 28.6.27. Appl., 11.1.26).—Casing sections mounted on a central shaft abut on opposite sides of a ring between them, means being provided for tightening them in position. A wall of filtering material is provided within each section between a clear space within the ring and a recess within the section, to which liquid to be filtered is supplied, the filtered liquid being discharged from the recesses through a bore in the shaft.
H . Ho l m e s.
Distillation and absorption column. C. H . B o r r -
m a n n (G.P. 439,204, 12.1.22).—The separate compart
ments of a column in which gases or vapours are scrubbed with a counter-current of a liquid contain filling material, and are connected by nozzle tubes so narrow that the velocity of the gas or vapour passing through them prevents gas or liquid from flowing in the opposite
direction. L . A. C o le s .
Continuous rectification of liquids. L . Gr a n g e r
( F .P . 613,879, 29.7.25).—The return flow of the cooling liquid from purifying apparatus working in conjunction with a rectifier is redistilled before it is returned to the
concentrator. L . A. Co l e s.
Clarification of liquids and recovery of the solid matter contained therein. R. J. M a r x (E.P. 272,130, 3.2.27).—The clarification of liquids having solids in suspension is effected by apparatus which comprises means for the detachment of the air bubbles adhering
591 a
B r itis h C h e m ic a l A b s tr a c ts —B .
592 C l. I I . —Fxtbl ; G as ; D e s x ru c tiv * D i s t i l l a t i o n ; M in k e a l O ils.
to the solids witli a view of increasing the sp. gr. of the solids, and means, in the form of a continuous-flow settling tank, for the separation of the solids from the liquid. To remove the air bubbles, the liquid with the matter in suspension is allowed to flow, first, into a small shallow receptacle at such a rate as to overflow the rim thereof in the form of a thin film tending to form separate drops, and then to fall oil to an inverted dished disc which is fixed at the surface of the liquid contained in the inlet chamber of the settling tank. The settling tank comprises a central inlet chamber of tapering form in open communication at the base with a simi
larly formed outer container, which is provided with an outlet at the bottom for the removal of the deposited solids and a surrounding trough at its upper part to receivc the clarified effluent. W. T. Lo c k e t t.
Determination of [a constituent of] gas [m ix
tures]. R. P. Ma s s (U.S.P. 1,634,331, 5.7.27. Appl., 15.5.26).—A given constituent in a mixture of gases is determined by causing the mixture to flow constantly at a volumetrically uniform rate and removing the par
ticular gas. The stream then flows through a constricted passage, and the differential pressure of the residual gas on the opposite sides of the constricted passage is
indicated. W. G. Ca r e y.
Gas analysing apparatus. Sv e n s k a Ak t ie b o l a g e t
Mono (E.P. 257,609, 24,8.26. Conv., 28.8.25).—In a gas analysis apparatus with an oscillating liquid column and with the absorption liquid used as sealing and pumping liquid, the absorption liquid is forced into a closed system of vessels partly filled with mercury.
The mercury is consequently driven up until it is dis
placed, when the absorption liquid flows over into the measuring and absorption vessel, from which it flows back into the reservoir. Gas may thus be collected without coming into contact with the absorption liquid, which, further, is effectively renewed for each analysis in the absorption vessel. R. A . A. Ta y l o r.
Gas analysis apparatus. S. S. Levestsohn (E.P.
272,092, 28.10.26).—The apparatus consists of a 100 c.c.
measuring burette, several absorption vessels, and a capillary tube for complete combustion. The absorption vessels are made with two interconnected chambers ; the gas enters the vessel, bubbles through the reagent, and is withdrawn for measurement. The measuring burette has two jackets containing water, the inner jacket or bell being connected with the capillary tube used for the combustion of the gas. A. C. Mo n k h o u se.
Production of cold. I. Am u n d s e n (E.P. 266,683, 11.1.27. Conv., 27.2.26).—Activated charcoal is used to adsorb and expel, alternately, methyl alcohol or ethyl alcohol, either of which thus acts as a refrigerating
agent. W. G. Ca r e y.
Separating m aterials of different specific gravi
ties. T. M. Ch a n c e (Re-issue 16,674,15.3.26, of U.S.P.
1,559,938, 7.7.22).—See B., 1926, 33.
Apparatus for charging furnaces, gas-producers, or the like. Woo dall- Du c k h a m (1920) Lt d., a n d S. N.
We l l in g t o n (E.P. 272,820, 28.3.27).
Optical pyrometer. R. Ha s e(E.P. 272,799,18.1.27).
Em ulsions (E.P. 247,588).—See XX.
II.— FU EL; GAS; DESTRUCTIVE DISTILLATION;
MINERAL OILS.
Technical and economic considerations on the better utilisation of coal with especial reference to high-pressure processes. C. Kr a u c h (Stahl u. Eisen, 1927, 47, 1118—1126).—The present position, as far as concerns the I . G . Farbenindustrie, of the problems of the economic production of hydrogen for ammonia synthesis and of the conversion of coal into liquid fuel is discussed.
The cheapest process so far evolved as a solution of the first-named problem consists in using low-grade bitu
minous coal or lignite in a finely-divided form in a specially constructed producer in which a layer of the fuel 2 m. high is treated alternately with air and steam under just sufficient pressure to keep the particles suspended in a gas cushion so that the whole mass appears to be in a state of fluidity. The gases leave the producer at 1000°, and their heat is utilised in drying fresh charges of fuel, which is allowed to fall into the gas stream and is subsequently separated in a cyclone apparatus. The gas issuing from this passes over a catalyst which causes the carbon monoxide and the steam to react with the production of hydrogen and carbon dioxide. After removal of the latter by washing, the remaining gas consists of hydrogen and nitrogen in the correct propor
tions for use in the Haber process. The carbon dioxide is utilised in the ammonia-soda process or in the manu
facture of ammonium sulphate from gypsum. A short historical survey of the development of the manufacture of methyl alcohol, hydrocarbons, and other organic compounds from carbon monoxide and hydrogen by the use of various catalysts, and of the direct hydrogenation of coal to obtain liquid fuels and various aliphatic and aromatic hydrocarbons by the use of catalysts and high pressures is given, followed by a discussion of the economic possibilities of products in competition with natural petroleum products. A. R . Po w e l l.
Carbonisation. II. Size of coal, admixture, inorganic compounds. 18th Re p. o f Re s. Sub-
Co m m. o f Ga s In v e s t ig a t io n Co m m. In s t. Ga s En g. (G as
World, 1927, 8 6, 622—633).—The effect of size of coal particle and admixture of coal fcof different mesh), coke, calcium carbonate, iron oxide, and sodium carbonate upon the yields and properties of the products obtained from the carbonisation of a Nottinghamshire coal was investigated (cf. B., 1926, 1001). The same cronite retort was employed as in the previous experiments, but the retort temperature was reduced from 980° to 915°.
The coal was graded into different sizes, 1£ in.—f in., i in.— I in., and 10—30 mesh, in such a manner that each grade was of similar composition, and carbonisation tests were carried out with each grade and with mixtures of the grades. The rate of gas evolution varied slightly with the different grades, but in the case of mixed grades was reduced by as much as 14% in the early stages of carbonisation. The admixture of 10 and 20% of coke to the coal (both of 10—30-mesh) gave results which showed an increased yield of 2-7 and 1 • 9 therms per ton, respectively, but a decreased yield of tar per ton of 0 • 9 and 1-7 gals., respectively. The effect of adding 3-4%
of calcium carbonate, 2-2% of iron oxide, and 3-3% of sodium carbonate to the coal (10—30 mesh) was in each
B r itis h C h em ica l A b s tr a c ts —B .
Cl. IL— Fü e l ; Ga s ; De s t r u c t iv e Dis t i l l a t i o n ; Mi n e h a l Oi l s. 6 9 3
case to increase the volume and thermal value of the gas made per ton, the increase in the thermal value being greatest with sodium carbonate (12%) and least with iron oxide (2%). The calorific value of the gas was re
duced owing to the presence of increased quantities of carbon monoxide, carbon dioxide, and hydrogen. The volume of the two oxides of carbon produced was in excess of that obtainable from the decomposition of the compounds added to the coal, but it is suggested that the additional hydrogen may be accounted for by the catalytic acceleration of the water-gas reaction within the coke charge. H. D. Gr e e n w o o d.
Influence of the bitumen content of lignite dust on its explosiveness and temperature of spon
taneous ignition. H. St e in b r e c h e r (Brennstoff- Chem., 1927, 8, 193—195).—Removal of the bitumen by extraction raises the temperature of initial decom
position, and lowers the explosiveness of lignite dust.
The nature of the bitumen also has an influence, resins imparting a greater explosiveness than waxes. The temperature of spontaneous ignition is lowered by removing the bitumen, though this efiect may be masked by the opposite effect of the accompanying increase in ash content and diminution in the content of volatile matter of the dust. W. T. K. Br a u n ho ltz.
Ternary coal m ixtures. III. D. J. W. K reulen (Chem. Weekblad, 1927,24, 255—258).—Further ternary mixtures of coals have been examined in the same way as before, and the factors governing the formation of coke are discussed, under the headings (1) nature of infusible residue, (2) proportions of fusible binding bitumen, and (3) properties of the bitum en; the influ
ence of particle size is also considered (cf. B., 1927,
289). S. I. L e v y .
Retention of certain hydrocarbons by solid fuels.
B. Mo o re and F. S. Sin n a t t (Fuel, 1927, 6 , 312—
318).—The rates of absorption of benzene, toluene, and xylene by powdered coal, peat, gas coke, and charcoal, a t 16°, and the rates of loss of the hydrocarbon on subse
quent exposure of the sample to the air have been de
termined. The samples were ground to pass 200-mesh, and were dried at 105°. The rate of absorption fell to a very small value after 15 hrs.’ exposure to the vapour ; the amounts of benzene then absorbed under the con
ditions of the experiment were approximately: bitu
minous coal 18-5%, anthracite 15-2%, gas coke 1%, peat 0-2%, animal charcoal 16-5%, wood charcoal 6-6%. Most of the absorbed vapour was readily removed, but after 480 hrs.’ exposure to dry air the coal samples still retained appreciable amounts of benzene (2—3% ); even considerably longer exposure to air failed to remove completely the absorbed hydrocarbon, which, however, could be recovered by passing a current of air over the fuel at 180°. Treatment of the fuels with a hydrocarbon had practically no influence on their capacity for absorbing moisture, but decreased slightly the tendency of the coals to ignite. A. B. Ma n n in g.
Products of combustion from typical gas appli
ances. II. Gas fires. 17t h R e p . o f R e s . Sub-Com m . o f G a s I n v e s t i g a t i o n Comm. I n s t . G a s E n g . (G a s W o rld , 1927, 86, 597—603).—E x p e r im e n ts a r e d e s c r ib e d to d e te r m i n e t h e a m o u n t o f c a r b o n m o n o x id e p r e s e n t in
the products of combustion from gas fires, the gas being burned at varying rates up to 30% in excess of the capacity of the fires and under various conditions of primary aeration. Two gas fires were selected, one being a pre-war model (1911), the other being of modern design. The results are expressed in parts of carbon monoxide per 10,000 parts of gas burned. With the modern fire and normal aeration (air-gas ratio 1-48) the carbon monoxide increases from 15 pts. at half normal gas rate to 30 pts. a t the normal r a te ; on increasing the air-gas ratio to 1-90 the production of carbon monoxide is reduced to 16 pts. at normal gas rate. At low aeration (ratio 1-38) the older fire gives 16 pts. of carbon monoxide at half gas rate and 235 pts.
at normal rate, whilst on increasing the aeration ratio to 1 • 87 the production of carbon monoxide is diminished to 7 and 80 pts. respectively. The smaller carbon monoxide production in the case of the modern fire Í3 attributed to greater uniformity in the quality and rate of discharge of the air-gas mixture. Although the concentration of carbon monoxide in the flue gases is usually below 1 pt. per 10,000, this is regarded as sufficient to justify the provision of an efficient flue.
H. D. Gr e e n w o o d.
Equilibrium conditions in the formation of hydrocarbons and alcohols from water-gas. D. F.
S m i th (Ind. Eng. Chem., 1927, 19, 801—803).—The changes in free energy involved in the formation of methane, ethane, propane, or benzene, and methyl, ethyl, or propyl alcohols, from carbon monoxide and hydrogen, have been calculated as functions of the temperature, and the values of the equilibrium constants at 25°, 300°, and 400° have been deduced therefrom.
A tendency is shown towards the formation of the higher rather than the lower members of the paraffin series, and of the aromatic rather than the straight- ehain compounds. The lower alcohols cannot be formed from water-gas at atmospheric pressure and tempera
tures of 300° and above, whereas the production of considerable amounts of the higher alcohols is possible under these conditions. The tendency to form all these compounds falls off rather rapidly with rising tem
perature. A. B. M a n n i n g .
Carbonisation of wood. I. Acids of crude pyroligneous acid. J. Seib (Ber., 1927, 60, 1390—
1399).—Fractional distillation of the “ residual acids”
from pyroligneous acid is not a suitable process for the separation of the mixture into its components. Better results are obtained by use of the methyl or ethyl esters, but the isolation of homogeneous compounds depends mainly on individual processes. The following acids have been isolated: propionic, butyric, isobutyric, isovaleric, a-methylbutyric, n-hexoic, wohexoic, heptoic, methacrylic, tiglic, and Aa-pentenoic. The presence of y-butyrolactone, y-valerolactone, and durene is estab
lished. The unsaturated acids all contain the double linking in the aß-position, and where stereoisomerism is possible only the trans-form appears present. Angelic acid, obtained by Krämer and Grodzki, is a mixture of tiglic and A“-pentenoic acids, whilst the Mocrotonic acid of these authors is a mixture of solid crotonic acid, a-methylbutyric acid, and J.sovaleric acid.
H. Wr e n. a 2
B r itis h C h e m ic a l A b s tr a c ts —B .
694 C l . I I .—F u e l ; G a s ; D e s t r o c t i t s D i s t i l l a t i o h ; Mi n b r a l O i l s .
Unsaturated hydrocarbons in oils obtained from petroleum . 6. Ga n e and (Mrs.) M. Zil is t e a n u- Gh e o b g h iu (B u i. Soc. Chira. Romp.nia, 1926,8, 3—10).—
Values of dla, ignition temperatures, viscosities, congel
ation temperatures, and iodine values of a series of oils from the Steaua Romana and Vega refineries have been determined and the results tabulated. Two methods are described for determining amylene in presence of hexane, benzene, and mesitylene, and it is found th at light petroleum, d 0-730, contains 12-5% of unsaturated hydrocarbons. H. Bu r t o n.
Polym erisation and other chemical reactions in the sulphuric acid refining of cracked distillates.
•T. C. Mo e e e l l (Ind. Eng. Chem., 1927,19, 794—801).—
Determinations have been made of the losses due to polymerisation and dissolution which occur during the refining of cracked distillates from Californian and Mid-continent oils with different amounts of sulphuric acid. Using 1*55% by vol. of acid, the polymerisation losses are less than 2% and 1% (calculated on the gasoline fraction) respectively, with cracked distillates from the two types of crude oil. A negative polymerisa
tion loss observed with cracked distillates from the Cushing field is attributed to the polymerisation of very low-boiling hydrocarbons which are lost during fractionation of the untreated distillate. The sum of the dissolution losses on acid treatm ent of the gasoline and gas-oil fractions of a Mid-continent cracked distillate agrees with the loss on treatment of the original distillate before fractionation, but the corresponding sum in the case of the Californian distillates is greater than the direct dissolution loss. Sulphuric acid treatm ent causes no appreciable change over the greater part of the dis
tillation curves of Californian cracked gasolines, but produces a definite displacement (towards higher b.p.) of the curve for Mid-continent oils. In all cases there is a pronounced rise of the end b.p. of the treated gasoline, due, not only to polymerisation, but to the formation of sulphuric acid esters, which decompose on distillation, giving high-boiling, tarry residues. Sulphuric acid refining of cracked gasolines results mainly in a decrease in the percentage of unsaturated hydrocarbons, the content of aromatic, naphthenic, and paraffin hydro
carbons being only indirectly affected.
A. B . Ma n n in g.
Specific and sensible heats of petroleum oils.
0. G. Wil s o n, j u n. (Ind. Eng. Chem., 1927, 19, 824—
825).—Nomographic charts have been constructed to give the sp. lit. and the sensible heat above 0° F. of petroleum oils as functions of the temperature and the sp. gr. They are based on the formula of Fortsch and Whitman (B., 1926, 810). A. B. Ma n n in g.
Refractom etric examination of liquid fuels. K.
R. Die t b ic h (Chem.-Ztg., 1927, 51, 509—510).—Results of the refractometric examination of a series of mixtures of petrol, benzine, and benzol with an immersion refractometer are described. Since petrol has the lowest refractive index, addition of either benzine or benzol or mixtures of the two can be easily detected and measured by a refractometric determination. Pre
cautions to be observed in the determination .are stated, and a simple apparatus for the circulation of warm water is described. E. H. Sh a r p l e s.
Direct production of end-point petrol from cracking plants. K. Ne u b r o n n e r (Chem.-Ztg., 1927, 51, 508—509).—The conditions necessary for the pro
duction of cracked spirit free from resinifying and acid constituents and requiring no more refining are discussed.
E .H . Sh a r p l e s.
Determination of hard asphaltum in cylinder oil.
A. Bo u rg o si(Bull. Fed. Ind. Chim. Belg., 1927, 6, 201—
204).—The amount of asphaltum precipitated from mineral oils by benzine is greater the richer the benzine is in light constituents. The benzine can be used repeatedly provided the percentage of volatile constituents is not too high. When asphaltum is determined by Ilolde’s method (“ Kohlenwasserstoffe und F e tte ” ) it is thus essential to know the distillation limits of the benzine
used. S. K. Tw e e d y.
Apparatus for gas analysis. Pe r q u i n.—See I.
Gas analysis apparatus. Fr e d e r i c k.—See VI.
Penetrance of oils in wood. Ho w a l d.— S ee IX.
Pa t e n t s.
Manufacture of granular carbon. St a n d a r d
Te l e p h o n e sa n d Ca b l e s, Lt d. From We s t e r n El e c t r ic
Co., In c. ( E .P . 272,279, 8.3.26).—A carbonaceous material is distilled at 800—1100° in an atmosphere of hydrogen a t a rate such th at low porosity is induced in the granular product, which is then heated at a higher temperature so th at a roughened surface is imparted by the chemical action of an atmosphere of controlled oxidising power. The granular carbon is for use in microphones. R. A. A. Ta y l o r.
Reactivating exhausted, pulverulent, decolorising charcoal. Ve r e i n f. Ch e m. u.Me t. Pr o d. ( E .P . 264,799, 16.11.26. C o n v ., 22.1.26).—T h e c h a r c o a l is a g g lo m e r a t e d i n a p re s s , t h e fo r e ig n s u b s ta n c e s (s u g a r e tc .) a c ti n g a s b in d in g m a t e r ia l, a n d is t h e n i g n i te d in a s u i t a b l e f u r n a c e , s u c h a s a v e r t ic a l s h a f t f u r n a c e , t h e ig n i te d p r o d u c t b e in g w a s h e d in w a t e r o r d il u t e h y d r o
c h lo r ic a c id . W. G. Ca r e y.
Method and apparatus for cooling coke. Ko p p e b s
Co k e Ov e n Co., Lt d. From H. Ko p p e e s (E.P. 271,327, 29.10.26).— The coke is fed into a vertical shaft of such depth that the cooled coke prevents ingress of air or loss of gases. The coke is cooled by inert gases being blown transversely through the centre of the coke column, the partially heated gases being then withdrawn and blown through the top of the coke column, where they attain a temperature of 700—800°
and pass to a waste-heat boiler. A. C. Mo n k h o u s e.
Drying coke and the like. H. Fl e is s n e e (U.S.P.
1,632,829, 21.6.27. Appl., 11.1.26. Conv., 14.8.24).—
The coal is heated for 1 hr. in the presence of steam at a pressure of from 3 to 25 atm. corresponding to 130—
235°. The pressure is then gradually reduced until the coal is dry. A. C. Mo n k h o u s e.
Manufacture of water-gas. Hu m p h r e y s & Gl a s
g o w, Lt d., and J. C. St e l f o x (E.P. 272,026, 18.5.26).—
Where the “ back-run ” method of operating a gasi
fication plant is adopted (cf. E.P. 246,970; B., 1926, 477), in addition to a limited back-run with steam super
heated in the recuperators, gas alone is circulated by fan or blower through the recuperators and the entire
B r itis h C h e m ic a l A b s tr a c ts — B .
Cl. I I .— Fu e l ; Ga s ; De s t r u c t i v e Di s t i l l a t i o n ; Mi n e r a l Oi l s. 595
fuel bed of the generator. Steam may be added at the inlet to the generator if desired. A. C. Monkh o u se.
Distillation of solid fuels. C. St il l (E.P. 272,375, 20.10.26).—The yield of volatile products from a charge undergoing carbonisation in intermittently operated and laterally heated retorts is improved by the withdrawal by suction of the vapours. This is effected through suitable tubes or channels, the entrance to which is located below the surface of the coal charge, so that the vapours are drawn through the interior of the charge.
R. A. A. Ta y lo r.
Manufacture of liquid and other hydrocarbons and derivatives thereof from coal and like mate
rials. I. G. F a r b e n i n d . A.-G. (E.P. 247,582, 247,587, 250,948, 272,829, 272,834—5, [ a , b , d, e ], 11.2.26,
[c , f ] , 14.4.26. Conv., [a ] , 14.2.25, [u ], 16.2.25, [c],
i5.4.25. Addn. [ b—f ] to E.P. 247,582).—(a) Solid car
bonaceous materials are treated at an elevated tempera
ture and under at least 50 atm. pressure with hydrogen or reducing gases containing hydrogen compounds.
Nitrogen compounds, with or without other catalysts, are introduced. Ammonia, for example, acts catalytic- ally, and as a reducing agent. The gases may be passed as a stream. By admitting steam, hydrogen may be generated in the reaction vessel from coal, hydrocarbons, or carbon monoxide, with the last of which the employ
ment of the gases in a stream is rendered imperative.
The conditions may be regulated to promote the forma
tion of nitrogen compounds from free nitrogen, (b) Dis
tilled or extracted derivatives of coal etc. or their fractions are used as raw material instead of solid car
bonaceous materials, (c) Mineral oils or bitumens or fractions thereof are used as raw m aterial; but if the reducing gas is ammonia, some other nitrogenous catalyst, e.g., silicon nitride, is necessary, (d) When solid catalysts or porous materials are used, they are arranged in a separate contact vessel placed after the reaction vessel, so th at only the vapours of the resulting products reach them, (e) The raw material consists of products or their fractions obtained by the hydrogenation of solid carbonaceous materials, ( f ) Conversion or hydrogena
tion products of mineral oils and bitumens are used.
R. A. A. Ta y lo r.
Manufacture of liquid or other hydrocarbons and derivatives thereof from coal and like mate
rials. I. G. Fa r b e n in d. A.-G. (E.P. 247,583, 272,830, 272,833, 11.2.26. Conv., [a], 14.2.25. Addn. [b, o] to E.P. 247,583).—(a) Solid carbonaceous materials are treated, at an elevated temperature and under at least 50 atm. pressure, with hydrogen or reducing gases con
taining hydrogen, in the presence of molybdenum or its compounds, mixed, if desired, with other catalysts or inert materials {e.g., iron, calcium carbonate), (b) The molybdenum catalyst is assisted in its action by zinc oxide, magnesia, silica, coke, or activated carbon, the gas being passed in a stream, (c) Tarry products ob
tained by destructively hydrogenating solid carbonaceous materials are used as raw material, and the molybdenum catalyst is assisted by silicate of aluminium or magnesium or a mixture of these. R. A. A. Ta y l o r.
Manufacture of hydrocarbons and derivatives thereof from coal and like solid m aterials. I. G.
Fa r b e n in d. A.-G. (E.P. 247,584—5, 272,831—2,11.2.26.
Conv., [a], 14.2.25, [b], 16.2.25. Addn. [b—d] to E.P. 247,584).—(a) Solid carbonaceous materials are treated a t an elevated temperature and under at least 50 atm. pressure with hydrogen or reducing gases containing combined hydrogen, sulphur compounds {e.g., the sulphides of the heavy metals, especially of the iron group) being admixed as catalysts, (b) Instead of solid carbonaceous material, distilled or extracted derivatives thereof are used as raw material. The hydrogenating gases may be used in the form of a stream, (c) In using a stream of gases the process can be rendered continuous, (d) The products of destructive hydrogenation of solid carbonaceous materials and products distilled or extracted therefrom, e.g., coumarone resins and waxes from lignite, serve as raw material.
R . A. A. Ta y l o r.
Converting high-boiling hydrocarbons, which have been freed from the substances soluble in liquid sulphurous acid, into low-boiling hydro
carbons by m eans of aluminium chloride. Al l g e m. Ge s. f ü r Ciie m. In d. m.b.H . (E.P. 271,042 and 272,433, 11.3.27. Conv., [a], 12.5.26; [b], 19.6.26).—(a) The products obtained by freeing high-boiling hydrocarbons from constituents soluble in liquefied sulphur dioxide or by splitting with aluminium chloride or double compounds of aluminium chloride (Edeleanu process) are
(a) first of all split up by the action of small quantities of aluminium chloride, and the product so obtained is converted into low-boiling hydrocarbons by further treatment with aluminium chloride or worked up into marketable oils by the usual refining agents ; or (b)
subjected to renewed treatment with liquid sulphur dioxide, which process, after further treatment of the product with small quantities of aluminium chloride, is repeated until most of the Edeleanu refined product is converted into light hydrocarbons.
R . A. A. Ta y l o r.
Fractional distillation and condensation [of oil].
J. E. Be l l, Assr. to Sin c l a ir Re f i n i n g Co. (U.S.P.
1,619,396, 1.3.27. Appl., 14.10.21).—Oil to be distilled cascades through a series of stills at successively higher temperatures. The vapours from each still preheat the oil flowing into th at still, and the condensed vapours are separated. The uncondensed vapours from each preheater are utilised to heat the still at the next lower
temperature. S. Pe x t o n.
Production of bitum en or oil em ulsions. H . E.
Potts. From M i n e r a l A.-G. B r i g (E.P. 271,177, 24.2.26).—The emulsions are prepared from any bitu
minous substance, but reference is made to “ Mexphalte ” and “ Spramex.” The bitumen is mixed with sulphurised factice oil, fatty acids, or resins, such as are obtained by the action of sulphur chloride on train oil, fatty acids, or resins, or from linseed oil and sulphur heated a t 150—180°. The mixture is emulsified with alkali in a high-speed colloid mill. In certain cases alkali is added so th at only a portion of the oil added is saponified, the remainder in the presence of air and sunlight being converted into an asphalt. Lignite, brown coal, or alkali extracts of these may be also added. The emulsion is diluted with soap solution or other saponifi
cation product of a complex fatty amino-acid.
A . C. Mo n k h o u s e.
B r itis h C h e m ic a l A b s tr a c ts — B .
6 9 6 Cl. I I I . — Ta r a n d Ta u Pr o d u c t s.
Working-up acid resins, obtained from the refining of mineral oil derivatives, into natural bitumens. F. Wil h e l m (E.P. 254,674, 26.11.25).—
The raw acid resins, produced in the refining of mineral oils by sulphuric acid washing, are heated in agitators, the sulphuric acid which separates being drawn o£E in regulated quantity so as tojleave 1—3% in the resin.
After further heating at 130°, a stream of hydrogen sulphide is passed in or sufficient sulphur is added to reduce the sulphuric acid to sulphur, which reacts with the resin forming a bituminous product, the hardness of which can be controlled by variation of the proportion of acid left in the resin prior to the reduction stage.
S. Pe x t o n.
Treatment of petroleum products. J. C. Bl a c k,
W. D. Ria l, and R . T. Ho w e s, A ssrs. to Pa n Am e e ic a n
Pe t r o l e u m Co. (R e -issu e 16,679, 26.10.26, of TJ.S.P.
1,592,329, 1.6.25).—S ee B., 1926, 863.
Separating water and other impurities from mineral and other oils or liquids. H . J. Ho l f o e d,
Assr. to P. P. Ha r v e y (U.S.P. 1,635,845, 12.7.27.
Appl., 9.9.25. Conv., 8.11.24).—See E.P. 238,750;
B., 1925, 838.
Purification of liquid hydrocarbons. Al l g e m. Ge s. f u e Ch e m. In d. m.b.H . (E.P. 258,846, 11.8.26.
Conv., 26.9.25).—See G.P. 432,580; B., 1927, 210.
Air-gas producing apparatus. L. Br e g e a u t(E.P.
264,482, 7.1.27. Conv., 14.1.26).
[Valve for] gas-retort plant. R . De m p s t e b &
So n s, Lt d., and H. J. Toogood ( E .P . 273,063, 19.5.26).
Gas analysis apparatus (E.P. 257,609 and 272,092).
— S ee I.
Distillation of oils (G.P. 439,044).—See III.
III.— TAR AND TAR PRODUCTS.
Solubility of naphthalene.’?; G. ^ We is s e n b e e g e e
(Z. angew. Chem., 1927, 40, 776).—Tables and curves for the solubilities of naphthalene expressed in g. of the solid per 100 g. of solution, at temperatures from — 14°
to 50°, in various solvents are given. The best solvent is tetralin, 100 pts. of the solution containing 30 pts.
of the solid at 13°, and 60 pts. at 60° ; then, in order of solvent power come decalin, hexalin, and methylhexalin.
S. I . Le v y.
Distinguishing tests for carbolic acid, the cresols, and certain other phenols. A. H. Wa e e (Analyst, 1927,52,335—337).—One drop of the phenol is dissolved in 10 c.c. of hydrochloric acid, 0-5 g. of a mixture of sodium nitrite (1 pt.), potassium or sodium nitrate (1 pt.), and dehydrated sodium sulphate (2 pts.) is added, and the whole stirred. After 2—5 min. the colour (a) is noted and then 1 c.c. of the acid mixture is poured into excess of 10% ammonia solution, and any colour change (b) again noted. Carbolic acid gives a rich crimson colour (a), changing on addition of 1—2 drops of 38% formaldehyde to purple, which on pouring into ammonia solution becomes deep blue. o-Cresol gives (a) a dichroic solution with green predominating, changing with formaldehyde to blue and with ammonia solution to olive-green. Both m- and ^-cresol and
“ Cresol B.P.” fail to give any distinctive results, and jj-cresol inhibits the reaction with carbolic acid or o-cresol. (j-Naphthol and a-naphthol give for (a) a crimson-purple and violet-purple, respectively, and for (b) the colour is destroyed. Thymol gives (a) a green and (b) a yellow colour. “ Cresol B.P.” gives similar results to »i-cresol and “ Creosote B.P.” to guaiacol.
D. G. He w e e.
Detection of carbolic acid in com m ercial cresols.
A. H . Wa r e (Pharm. J., 1927, 118, 775—776).—The B.P. test for the detection of phenol in cresols is stated to be useless, and the following is advised : the cresol is shaken with 0-1A'-potassium hydroxide, and, after separating, the upper layer is removed, shaken with ether, acidified after removal of the ether, and finally extracted with ether. The residue after evaporation of the second ether extract is acidified and stirred with a mixture of sodium nitrate and nitrite, the presence of phenol being shown by a crimson coloration (cf. preceding
abstract). B. Fu l l m a n.
Determination of phenol and cresol [in lysol].
K. K. Ja r v in e n (Z. anal. Chem., 1927, 71,108—117).—
Determination of cresols gravimetrically by extraction with other is unsatisfactory, because it is difficult to dry to constant weight. I n the cold, cresol takes up, in general, two atoms of bromine, but the amount in
creases with the excess of bromine used. The following method is recommended for the determination of cresols in lysol. The fatty acids in a solution of 10 g.
of 50% lysol in 100 c.c. of water and 30 c.c. of 2Ar-potas- sium hydroxide are precipitated with 30 c.c. of iV-barium chloride solution, and the mixture is made up to 200 c.c.
To 5 c.c. of the clear liquor are added 120 c.c. of water, 50 c.c. of 0 • 22V-bromide-bromate solution, and 25 c.c.
of 2/'/-hydrochloric acid. After | hr., 10 c.c. of a 20%
potassium iodide solution are added, and the iodine liberated is titrated with 0-2A7-thiosulphate. The bromine number of the mixture of cresols in the lysol is determined by extracting an acidified fresh portion of 50 c.c. of the solution twice with 25 c.c. of a mixture of equal parts of ether and benzine of b.p. 50°, driving off the solvent on the water-bath, drying for i hr. at 100°, and weighing, then brominating one-tenth of the product exactly as described above. The error of the method is about 1%. The iodine method of Messinger and Vortmann also gives satisfactory results provided th at the solution is kept cold and is first acidified and then neutralised with magnesia, so th a t the alkalinity is always the same. R. Cu t h i l l.
Pa t e n t s.
Refining tars. Sie m e n s u n d Ha l s k e, A.-G., Assees.
of C. Ha e e ie s (G.P. 439,005, 22.7.22).—The tars, or tar oils, are mixed with higher alcohols, e.g., amyl alcohol, or their derivatives, and the mixture is extracted with alcohol. The refined oil and the extract are freed from alcohols by distillation in vacuo, or at the ordinary pressure, with or without steam. A. B. Ma n n in g.
Continuous distillation of tars and oils. R.
Bl u m n e e (G.P. 439,044, 4.2.25).—In the cracking of tars and oils by passage of the liquid through molten metal, the heated liquid is led from the autoclave to a well- lagged pressure container; it vaporises only on being
B r itis h C h e m ic a l A b s tr a c ts —B .
Cl. I V . — Dy e s t u m s a n d In t e r m e d i a t e s. 597
d is c h a rg e d fr o m th i s c o n ta in e r, a n d is t h e n fr a c tio n a lly
c o n d e n s e d . A. B . Ma n n in g.
Separation of tars, tar oils, etc. into fractions.
J. A. Du i j t s (Dutch P. 15,083, 5.12.24.).—The material is mixed with alkali and oils rich in phenols, which, e.g., like low-temperature tar, are miscible with tar and tar oils. The mixture is then allowed to separate out, the various layers being drawn off and worked up inde
pendently ; or the mixture may be separated by centri
fuging. A. B. Ma n n in g.
Production of lower - boiling oils from low- temperature tars or tar oils. Co m p, d e s Min e s d e Vic o ig n e, No e u x, e t Dr o c o u r t (P.P. 614,229,1.7.25).
-—The tars or tar oils, freed from phenols, are distilled in the presence of aluminium chloride.
A. B. Ma n n in g.
Distillation of tar. J. S. Mor g a n a n d D. Rid e r,
Assrs. t o Th e r m a l In d u s t r ia l & Ch e m ic a l (T .I.C .) Re s e a r c h Co., Lt d. (U.S.P. 1,635,896, 12.7.27. Appl., 1.6.22. C o n v ., 7.6.21).—See E.P. 184,624; B., 1922, 803 a.
I V — DYESTUFFS AND INTERMEDIATES.
Phenol fusion. P. H. Rh o d e s, D. W. Ja y n e,
j u n., and P. H. Bi v in s (Ind. Eng. Chem., 1927, 19, 804—807).—The effect of varying the temperature, amount of caustic soda, and time of heating, on the yield of phenol from the reaction between sodiumbenzene- sulphonate and fused caustic soda, has been studied.
The optimum conditions, giving a yield of 96% of the theoretical, are (a) a temperature of 350°, (6) an amount of soda 15% in excess of the theoretical, and (c) a 15-min. period of heating after mixing. Air must be excluded from the melt, and any local excess of sulphonate during mixing must be avoided. Among the oxidation products formed in the presence of air are the dihydroxy- diphenyls and carbon dioxide, whilst, in the presence of excess of sulphonate, phenyl ether and thiophenol are produced in considerable quantities.
A. B. Ma n n in g. Pa t e n t s.
Manufacture of azo dyes. I. G. Fa r b e n in d. A.-G., Assees. of Fa r b w. v o r m. Me is t e r, Lu c iu s, & Br u n in g
(E.P. 248,766, 5.3.26. Conv., 5.3.25. Addn. to E.P.
231,529; B ., 1925, 909).—Bordeaux dyes, yellower than those of the prior patent, are obtained in substance or on the fibre by coupling a 2: 3 - hydroxynaphthoic arylamide with a diazotised 2-amino-4-aroylaminodiaryl ether. Thus, 2-amino-4-benzamidodiphenyl ether is diazotised and coupled with 2:3-hydroxynaphthoic 5-chloro-o-tolylamide or a-naphthylamide.
C. Ho l l in s.
Manufacture of azo dyes. O. Y. Im r a y. From
I . G. Fa r b e n in d. A.-G. (E.P. 272,580, 9.3.26).—m-Nitro- p-aminophenyl ethers (especially methyl and ethyl ethers) are diazotised and coupled with an acetoacet- anilide containing an o-substituent or a y-alkoxyl group, giving yellowish-red pigments suitable for lakes. The second components used in the examples are the o-toluid- ide, jj-anisidide, m-4-xylidide, and 2-chloro-i-anisidide (m.p. 109—110°, made from o-chloro-jj-anisidine), of acetoacetic acid. C. Ho l l in s.
Manufacture of anthraquinone derivatives. I. G.
Fa r b e n in d. A.-G., Assees. of J. D. Rie d e l A.-G. (E.P.
248,759, 3.3.26. Conv., 3.3.25).—Hydrogenation of anthraquinone or its derivatives in the liquid phase (preferably in a solvent or diluent) in presence of a cata
lyst (especially the mixed catalyst of G.P. 369,374 ; cf. B ., 1923, 543 a) leads successively to the corre
sponding anthranols, tetrahydro- and octahydro- anthranols. The preparation of anthranol, m.p. 163—
165°, tetrahydroanthranol, m.p. 108° (benzoate, m.p. 142° ; acetate, m.p. 109°; »!ono6ro»zo-derivative, m.p. 123°), and octahydroanthranol, m.p. 124° (acetate, m.p. 52° ; benzoate, m.p. 128°; monobromo-derivittive, m.p. 123°), are described.
Tetrahydroanthraquinone (Schroeter, A., 1925, i, 127) and octaliydroanthraquinone, m.p. 180°, are obtained by oxidation of the respective anthranols. C. Ho l l in s.
Manufacture of anthraquinone paste. W. M.
Gr o sv e n o r and V. P. Ge r s h o n, Assrs. to W . M . Gr o s-
v e n o r(U.S.P. 1,631,589,7.6.27. Appl., 10.10.21).—Crude anthraquinone is sublimed in steam (3 pts.), being rapidly condensed by treatment with atomised water (20 pts.). A stable homogeneous paste containing about 20% of pure anthraquinone is obtained.
T. S. Wh e e l e r.
Recovery of antim ony in flavanthrone manu
facture. E. C. R . Ma r k s. From E. I. Du Po n t d e
Ne m o u r s & Co. (E.P. 272,597, 15.3.26).—The filtrate from the flavanthrone is distilled at ordinary or reduced pressure, and to the distillate, consisting of nitroben
zene, chlorinated nitrobenzene, and antimony tri
chloride, enough dry chlorine is added below 50° to convert the trichloride into pentachloride. The mixture is then used for further batches of flavanthrone. The recovery of nitrobenzene is 80%, of antimony penta
chloride 80—85%. C. Ho l l in s.
Manufacture of am ines of the cycfohexane series. I. G. Fa r b e n in d. A.-G., Assees. of Fa r b w.
v o r m. Me i s t e r, Lu c iu s, & Br u n in g (E.P. 261,747, 16.11.26. Conv., 17.11.25).—Secondary ci/cZohexylaryl- amines, obtained from cyclohexyl halides and arylamines, are alkylated, e.g., with methyl or ethyl sulphate, chloride, or p-toluenesulphonate. cycloE exylmethyl- aniline, b.p. 148—150°/12 mm., and cyclohexylethyl- aniline, b.p. 150—155°/12 mm., are described. The products are intermediates for basic and sulphide dyes.
C. Ho l l in s.
Pyrazolone dyes from amino-derivatives of 4-hydroxy-3-carboxydiphenyl sulphide. Br it is h
Dy e s t u f f s Co r p., Lt d., and M . Men do za(E.P. 272,024, 12.5.26).—The utilisation of the screening effect of a sulphide bridge (cf. E.P. 260,058; B ., 1927, 8) between the chromophoric and the chelate parts of the mole
cule is extended to the preparation of pyrazolones from hydrazino-4-hydroxy-3-carboxydiphenyl sulphides, which, when coupled with diazo compounds, give dyes practically unchanged in shade by chroming. Diazotised 2'-amino-4-hydroxy-3-carboxy-4'-sulphodiphenyl sul
phide, for example, is reduced to the hydrazine and condensed with ethyl acetoacetate to give a methyl- pyrazolone, which is coupled with diazotised sulphanilic acid (greenish-yellow after-chromed on wool, or chrome- printed on cotton), 2 : 5-dichloroaniline-4-sulphonic acid
B r itis h C h e m ic a l A b s t r a c t s —B .
598 Cl. Y .— Fi b r e s ; Te x t i l e s ; Ce l l u l o s e ; Pa p e r.
(redder shades), naphthionic acid (yellowish-orange), aminoazobenzene (orange), benzene-4-azo-l-naphthyl- amine-6 (or 7)-sulphonic acid (yellowish-red after-chromed on wool, red-brown chrome-printed on cotton), or with tetrazotised benzidine (orange after-chromed on wool, light brown chrome-printed on cotton). The corre
sponding pyrazolonecarboxylic acid gives redder shades.
C. Ho l l in s.
Preparation of triarylm ethane dyes. Br it is h
Dy e s t u f f s Co r p., Lt d., E. H . Ro d d, and F. W . Lin c h
(E.P. 272,321, 17.4.26).—Tetra-alkyldiaminodiaryl ke
tones combine with sodium (2 atoms), in presence or
«absence of a solvent, to form derivatives, which, by reaction with aryl halides, yield the carbinol bases of triarylmethane dyes: R2CO-»R2CNa-ONa-R2R'C-ONa.
The reactions may beperformedin oneoperation,thehalide being added after the sodium has dissolved. 4 : 4'-Tetra- methyldiaminotriphenylcarbinol and the tetraethyl homo- logue are obtained from tetramethyl- and tetraethyl- diaminobenzophenones, respectively, with chlorobenzene;
with /3-chloronaphthalene, carbinols melting, respec
tively, at 181° and 175—177° result. From tetra- methyldiaminobenzophenone with o-chlorotoluene a carbinol, m.p. 163°, is prepared ; with 4-chloro-»i-xylene, a carbinol, m.p. 145°. The salts of these carbinols are green or blue-green dyes. C. Ho l l in s.
Manufacture of acid dyes. I. G. Fa r b e n in d. A.-G., Assees. of Fa r b w. v o r m. Me i s t e r, Lu c iu s, &
Br u n in g (E.P. 252,390, 21.5.26. Conv., 22.5.25).—
A 1 : 3-dihalogeno-4 : 6-dinitrobenzene is condensed with 2 mols. of a p-aminodiphenylaminesulphonic acid to give yellow to brown dyes for animal fibres; other sub
stituents may be present. Thus 1 : 3-dichloro-4 : 6- dinitrobenzene with 4'-nitro-4-aminodiphenylamine-2'- sulphonic acid gives a yellow; with 4-aminodiphenyl- amine-2-sulphonic acid, a brownish-yellow; with 4-amino- 4'-methyldiplienylamine-2-sulphonic acid, an orange- yellow. 2 : 6-Dichloro-3 : 5-dinitrotoluene with 4-amino- diphenylamine-2-sulphonic acid gives a brown. The dyeings on wool are fast to light and fulling.
C. Ho l l in s.
Sulphur-black dye. 0 . Ze l l e r and C. Wa l d m a n,
Assrs. to Na t io n a l An i l i n e & Ch e m ic a lCo., In c. (U.S.P.
1,630,818,31.5.27. Appl., 12.5.22).—Sulphur-black dyes, obtained, e.g., by the action of sodium polysulphide on sodium dinitrophenoxide, are mixed in the crude moist condition with an excess of sodium sulphide, and dried under reduced pressure to give a stable product.
T S Wh e e l e r
Sulphonic acids (E.P. 253,118).—See XX.
V.— F IB R E S; TEXTILES; CELLULOSE; PAPER.
Technical use of chlorine for the decomposition of raw vegetable fibres. P. W a e n t i g , also H. W e n z l
(Papierfabr., 1927, 25, 340—341, 341—342; cf. B., 1927, 69, 292).—(a ) In reply to Wenzl the author con
firms his earlier statements regarding (a) the quantity of heat developed in the chlorination of pine-wood meal, (6) the resolution of pine wood by chlorine under pressure into bleachable cellulose of high a-cellulose content, and (c) the ratio of hydrochloric acid to combined chlorine in the chlorination of pine wood with chlorine gas and
chlorine water. The lower yields of pulp recorded by Wenzl in the chlorination of straw with chlorine water as compared with chlorine gas are attributed to losses in washing and not to any specific differences between the two methods, (b) Waentig’s conclusions are, in the author’s opinion, of more theoretical than practical value. Experiments on a semi-commercial scale have proved that, in practice, lower yields of straw pulp are obtained with chlorine water than with chlorine gas.
D. J. No r m a n.
Pine wood without lignin reactions. W . F u c h s
(Ber., 1927, 60, 1327—1330; cf. B., 1927, 405).—The preparation of pine wood without lignin reactions is easily effected without considerable loss in weight by oxidation with perbenzoic acid in ordinary daylight.
Oxidised wood yields more dextrose than ordinary wood and contains less lignin. The increase in the former appears to depend on increase in the cellulose content.
The lignin of oxidised wood does not differ greatly in elementary composition from hydrochloric acid lignin, but contains less carbon and considerably less methoxyl than the latter. With molten potassium hydroxide it affords one and a half times as much protocatechuic acid as ordinary lignin; it yields very little hydroxy- methylfurfuraldehyde when treated with superheated
steam. H . W r e n .
Som e factors in the copper number of cellulose.
H . L e B. G r a y and C. J. S t a u d (Ind. Eng. Chem., 1927, 19, 854—855).—Results obtained in the copper number determination are influenced by the rate of stirring, e.g., a sample of degraded cellulose gave with gentle stirring 1 -76, and without stirring 1-92. The difference is not due to aerial oxidation, since similar figures are obtained when determinations are carried out in an atmosphere of nitrogen. The copper number is also influenced by the degree of subdivision of the pulp. A sample of sulphite pulp had a copper number of 1-64 when cut into 6 mm. squares, and 1-40 when rasped.
This result may be due to preferential absorption of alkali from the Fehling’s solution, followed by the destruction of the reducing groups of the cellulose before contact with cupric ions is obtained, such preferential absorption being favoured by increase in the surface exposed. This view is supported by the observation that if sulphite pulp is heated with the alkaline tartrate solution for 45 min. at 100° before the copper sulphate is added, and from this point the copper number deter
mination is carried out as usual, the result is approxi
mately 50% of the normal figure, showing that the alkaline tartrate solution has destroyed the reducing groups to a considerable extent. W. J. P o w e l l .
H ydrolysis number determination for wood cellulose. L . F. H a w l e y and L . C. F l e c k (Ind. Eng.
Chem., 1927, 19; 850—852).—In the determination of hydrolysis numbers, 1 g. of the a-cellulose (Cross and Bevan method) from the pulp is heated with 100 c.c. of 15% sulphuric acid for 3 hrs. on a boiling-water bath, the loss in weight (%) being the hydrolysis number.
The yield of pulp in a given sample of wood is invariably lower than the a-cellulose content of the latter owing to the hydrolysis suffered by the cellulose during the pulping process. From determinations of the a-cellulose content
