British Chemical Abstracts. B.-Applied Chemistry. April 8 and 15

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BRITISH CHEMICAL ABSTRACTS

B.—A P P L IE D C H E M IS T R Y APRIL 8 and 15, 1932*

I — GENERAL; PLA N T; MACHINERY.

N ew tools for high-tem perature research. II. B.

Sosmak (Ind. Eng. Chem., 1931, 23, 1369—1374).—

Uniformity of temp, in an electric resistance furnace can be obtained only by use of a fan or of a liquid bath.

Fuel-fired furnaces give good uniformity if supplied with an eccentrically placed burner. Wire-wound resistance furnaces now employ P t wire containing 10—20% Rli and free from Ir. The latter metal is stated to be volatile and to affect the accuracy of a thermocouple.

Outside-wound alundum tubes are commonly used, as also are W-Mo resister tubes and granular graphite or carborundum resisters. The latest development of high-frequency induction heating is the use of electron tubes. This gives good uniformity and a wide range of control, but is still expensive. Recently a focusing mirror and heliostat have been constructed at Jena which give a temp, of over 3000° from solar radiation.

Recording potentiometers are now replacing milli- voltmeters. For most conditions above 1400° the dis- appearing-filament optical pyrometer is precise and accurate. The replacing of the human element by the photoelectric cell has not yet been accomplished, and the use of this apparatus for recording is therefore not possible. Recently a quant, colour pyrometer has been produced, accurate within ±25°. Laboratory refrac

tories are discussed. C. Ir w i n.

H igh-tem perature control : photoelectric-tube pyrom etry. L. R . Ro l l e r (Ind. Eng. Chem., 1931, 23, 1379— 1381).—The use of radiation for higli-temp.

control has a very great advantage in the rapid variation of energy radiated with temp. An automatic control is constructed by focusing the image of the furnace wall upon the plane of a diaphragm in front of a photo

electric tube. The current produced is amplified, the amplifier current is passed through a high resistance, and the voltage drop is impressed between the grid and filament of a thyratron tube. When the drop exceeds a predetermined val. (or the furnace a given temp.) an arc is struck which shuts off the supply of heat to the furnace. If two tubes are used an upper and lower temp, limit may be set. An accuracy to about 10° is

possible. C. Ir w in .

H igh-pressure technique. F. G. Ke y e s (Ind.

Eng. Chem., 1931, 23, 1375—1379).—Pressures up to 600 atm. can be measured with an accuracy of 0-0 1% by transmission through oil to a weighted piston rotating or oscillating in its cylinder. Such a piston is calibrated by comparison with a column of Hg, e.g., by measuring the v.p. of liquid C02 a t 0°. The piston const, increases slightly with time, due to the ageing of the steel. A

Hg U-tube with electrical contacts is used to ascertain equilibrium. Compressed-gas manometers and Bourdon gauges are not suitable for precise work. Temp, is measured preferably by a Pt-resistance thermometer.

Vol. measurement is most difficult owing to changes in the container. Glass tubes are unsuitable for pressures above 100 atm. Mild steel and alloy steels are good, but pure Ni has too great a tendency to plastic flow. The dilatation with pressure m aybe determined by giving the container a spherical or cylindrical shape, for which formulae are available, or by completely filling the system with Hg. The vol. changes with pressure for const, temp, are now determined with and without the inclusion of the container. The use of Hg as confining fluid is impossible at temp, above 330°, and the fluid must be confined with itself. C. Ir w i n.

Design and construction of special vacuum- drying apparatus for dehydration of products with low vapour pressure. G. F. Sm it h and 0. W.

Re e s (Ind. Eng. Chem., 1931, 23, 1328—1330).—The

vac. chamber is fitted with electrical space heaters in each tray to give a temp, of 150—300°, and the door is made vac.-tight by a tongue-and-groove joint with Pb gasket. A very large exhaust port and exhaust chamber precede the condenser. This is of multiple-tube type, electrically welded, and cooled with brine. A rotary oil vac. pump maintains a pressure of about 5 mm. Hg.

The condenser temp, is a little above 0°. The apparatus is suitable for dehydration of Mg(C104)2,6H20, which requires a temp, of 200—250° and very uniform heat distribution to prevent fusion. The v.p. of this salt at 250° is 10 mm. Hg. The dryer described holds

1 0 0 lb. of finished product and dehydration requires

20 hr. C. Ir w i n.

M erging of process steps. C. W. ^V^{o g t} (Ind. Eng.

Chem., 1931, 23, 1355—1357).—The merging of suc

cessive process steps, in the cases discussed (refrigeration and agitation), has led to remarkable economies in the ice-cream and lard industries, and the principle is capable of further application. I t consists in the continuous treatm ent of the material by agitating members as it passes through cooled tubes, into which the air which it is necessary to incorporate is also fed.

A great reduction is effected in the size of the apparatus, as compared with batch-working, and a saving of refrigerant occurs, due to the improved efficiency of agitation and the working in closed vessels. A more uniform product is obtained and automatic control is

possible. C. Ir w i n.

Catalysis. P. K . Fr o l ic h (Ind. Eng. Chem., 1931, 23, 1366—1368).—The most important developments in industrial catalysis are discussed. C. Ir w i n.

* T he rem ainder of th is set of A bstracts will appear in n ex t week’s issue.

291 a

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B r itis h C h e m ic a l A b s tr a c ts^— B .

292 Cl. I.—G e n e r a l ; P l a n t ; M a c h i n e r y .

W ood’s light and its applications. R. In t o n t i

(Giorn. Chim. Ind. Appl., 1932, 14, 23—27).—Methods of obtaining Wood’s light and of measuring the lumines

cence exhibited by different substances under its influence are described. Applications to the examination of vege

table oils, butter, vinegar, flour and food pastes, drugs, organic compounds, etc. are discussed.

T. H . Po p e.

Refractories for boiler furnaces.—See V III.

Pa t e n t s.

Furnaces for superheating steam and other purposes. Su p e r h e a t e r Co., Lt d. From Co m p, d e s Su r c h a u f f e u r s (B.P. 365,926, 7.5.31).—Methods of diluting fire gases with used gases under control of ther

mostats in the mixed gases and/or the steam are described. B. M. Ve n a b l e s.

Combustion of pulverised fuel in furnaces, more particularly locom otive boilers. St u g Ko i i l e n-

STAUBFEUERUNG PATENTVERWERTUNG G.M.B.H. ( B .P .

365,354, 12.2.31. Ger., 10.3.30).—The fuel and primary air are admitted in a horizontal direction through the front, and secondary air enters through inclined ports in the floor and back wall of the combustion

chamber. B . M . Ve n a b l e s.

D ust separators or collectors for use in con

junction with cem ent and sim ilar kilns. Vic k e r s- Ar m s t r o n g s, Lt d., L. D. Pa r k e r, and J. D. Sk y (B.P.

365,721, 29.11.30).—The wet slurry is pumped over a conical surface, which may be rotated, over and under which the waste gases are guided so as to pass through the curtain of falling slurry as well as contacting with the wet surface of the cone. The slurry is preferably circu

lated a t a much greater rate than th at of the net supply to the kiln. B. M. Ve n a b l e s.

Improving the heat econom y in rotary drum furnaces. Fe l l n e r & Zi e g l e r A.-G. (B.P. 365,933,

IS.5.31. Ger., 19.5.30).—The cement or other material under treatment is showered through the gases by means of hollow lifters which are inserted through the wall of the kiln and are cooled, either by water dropped in or air blown through according to the amount of heat to be removed, to prevent destruction of the metal of which they are made. B. M. Ve n a b l e s.

Surface apparatus for effecting transfer of heat.

0 . Ha p p e l (B.P. 365,898, 14.4.31).—Proportions for elliptical gilled tubes are given ; improved heat transfer is claimed. B. M. Ve n a b l e s.

Cooling or heating apparatus for m ilk or other fluids. Da i r y Ac c e s s o r ie s Co., Lt d., and E. A . Ma r t i n (B.P. 365,626, 18.10.30).—A heater or cooler is formed of corrugated plates the ridges of which are welded together either directly or to intermediate strips or plates in order th at the inner fluid may be made to follow a zig-zag course along the corrugations.

B . M . Ve n a b l e s.

Rotary cooling drum s m ore particularly for cooling margarine and other fatty substances.

N . V . Gr a s s o’s Ma c h i n e f a b r., ’s- He r t o g e n b o s s c h e Ma c h i n e f a b r. (B.P. 365,869, 18.3.31. Holl., 21.3.30).—

A rotary single-walled drum is cooled by the evaporation of a liquid which is sprayed upon the upper part of the

interior of the drum and maintained a t a level in the lower part sufficient to prevent any part of the surface becoming dry. B. M. Ve n a b l e s.

Means for reducing [grinding] ores, sands, etc.

T. W. Ke e t (B.P. 365,725, 2.12.30).—The machine com

prises one or more pairs of rolls between which is a disc rotating about a horizontal axis through which the axes of the rolls do not pass. The material is fed to both sides of the disc. B. M. Ve n a b l e s.

H am m er pulveriser. Co m i*. Fr a n q. Bu e l l Co m b u s t io n (B.P. 365,597, 17.10.30. F r . , 10.7.30).—T h e m a t e r i a l is s u p p l i e d t o t h e p u lv e r is in g c h a m b e r a t t h e lo w e s t p a r t o f t h e c ir c u m f e r e n c e o f t h e c a s in g ; a d j a c e n t is a p o c k e t f o r c a t c h i n g t r a m p F e , a n d a b o v e is a s e p a r a t o r o f t h e d c f le c tio n t y p e i n a s t a c k - l i k e c a s in g .

B. M. Ve n a b l e s.

Separation of interm ixed divided m aterials.

R. Pe a l e, W. S. Da v i e s, and W. B. Oa k e s(B.P. 365,606, 14.7.30. U.S., 19.9.29).—Coal or other material is stratified according to sp. gr. and separated in two stages, in the first of which pure coal and a middling are obtained, and in the second the middling is separated into a second concentrate of coal and a tailing. The second concentrate may bo marketed or returned as original feed. [Stat. ref.] B. M. Ve n a b l e s.

Apparatus for estim ating the m oisture content of cereal products and other finely-ground m aterials. J. Th o m l in s o n and E. A. Fi s h e r (B.P.

365,247, 17.11.30).-—An apparatus comprising two container compartments and one filter compartment is described, by which the loss of wt. on admixture of CaC2 with the material may be determined.

Preparation of aqueous em ulsions. E. Ma y e r,

and Ud d e h o l h s Ak t ie b o l a g e t (B.P. 365,844,25.2.31).—

Turpentine oil (from the sulphate-cellulose or charcoal industries) is used as the sole emulsifying agent for various substances in water, e.g., colophony, bitumen, asphalt, paraffin wax, pine oil. H eat may be used and the turpentine added before or during the simple mixing operation, which is alone sufficient. The use of stabilising agents is not excluded. B. M . Ve n a b l e s.

Treatm ent of em ulsions. R. He l l e r u d, N. V . In t e r n a t. Gr a d in Ma a t s., and Vi t a c r e a m, Lt d. (B.P.

365,586, 15.8.30).—The emidsion is passed through two or more homogenising devices a t successively reduced pressure, to lower their viscosity and increase their

stability. B. M. Ve n a b l e s.

Dewatering solid m aterials. P. T. Wi l l i a m s, and

Mi n e r a l s Se p a r a t i o n, Lt d. (B.P. 365,148, 8.10.30).—

A vac. drum filter is adapted to the collection of mineral pulps which contain rapidly settling material by raising the speeds of rotation and of flow to many times those hitherto used. The filter surface is composed of wire mesh having openings a t least 40%, preferably 55%, of the a r e a ; the size of the apertures should be about equal to th a t of the largest particles in the pulp. The rate of flow of pulp should be > 20, preferably 50, cub. ft. per hr. per sq. ft. of filtering area, taken all round the drum. To maintain this rate both trunnions should be used to draw' off filtrate. The cake is dis

charged by a short sharp puff of compressed air or steam

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Cl. I.— G e n e r a l ; P l a n t ; M a c h i n e r y . 293

for the admission of which the valve ports are situated, not in the trunnions, but just behind the filter surface, extending the full length of it and having sharp edges.

B . M . Ve n a b l e s.

Filters. J. J. V . Ar m s t r o n g. From J. B lick and S. B. Hi c k i n (B.P. 365,659, 28.10.30).—A filter, particu

larly used for lubricating oil etc., is formed from sawdust and several spaced layers of felt placed in a conico- cylindro-conieal vessel. * B. M. Ve n a b l e s.

Well filter. M. ^S^{a m s o n}and H. La n g e (B.P. 365,889, 7.4.31).—A lining for the wall at the bottom of a well is formed of spaced bars point-welded without projec

tions on either surface of the cylinder. Methods of holding the bars during welding are described.

B . M. Ve n a b l e s.

Liquid clarification tanks. M. P r u s s (B.P.

365,630, 20.10.30. Ger., 22.10.29).—A thickener is divided by a screen wall into inner and o u t e T z o n e s , in the former of which a single set of rakes is rotated at comparatively high speed and drags the greater part of the sediment to the centre. The screen is provided with deflecting members to prevent the rotation of the liquid in the inner zone extending into the outer. In the latter raking is necessary only a t much reduced speed or intermittently, whereby complete settling of very fine m atter is aided. Several methods of discharging the fine sludge from the outer z o n e of round or square

t a n k s are described. B. M. V e n a b l e s .

Centrifuging m aterials. Soc. An o n. Ra f f i n e r i e Ti r l e m o n t o is e (B.P. 365,989, 26.8.31. Ger., 27.8.30).—

Pulp containing both granular and colloidal constituents is centrifuged in a pervious basket. When the filtration stops, due to choking, the colloidal material is skimmed off the collected granular material and the centrifuging continued until the material is practically dry.

Centrifugal bow ls. Ak t i e b. Se p a r a t o r (B.P.

365,450, 4.5.31. Swed., 14.5.30).—In a separator having funnel-shaped guides leading to the peripheral outlets for solid matter, the guides are formed out of pressed sheet metal and are easily renewable.

Centrifugal m ixin g devices. A. Fu r o w ic z and A. Ba g e r (B.P. 365,420, 7.4.31).—A device of the type in which two fluids are admitted from opposite sides of a rotor and expelled together a t the periphery has the inlet areas smaller than those of the outlet, preferably as 2 : 3. B. M. Ve n a b l e s.

Apparatus for m ixin g two or m ore fluids.

W. V . Bo b y and C. Bo l d r y ( B .P . 365,513, 11.9.30).—

An apparatus particularly suitable for treating softened water with COa comprises an injector jet of the main or heavier fluid behind which is the entrance for the other fluid and in front of which is a bafile producing turbu

lence. B . M. Ve n a b l e s.

Instrum ents for m easurem ent of the density of liquids. An g l o- Pe r s i a n Oi l Co., L td . From H. S.

Gib s o nand B. C. S. Ma t t h e w s (B. P . 365,141, 18.9.30).

— A n instrum ent of th e eounterpoised-float typ e is enclosed in a pressure-tight casing and is placed in a by-pass to th e m ain flow of crude oil, or other liquid which would change its sp. gr. when th e pressure is

released. The float has flat faces perm itting expansion and is filled w ith a liquid which is the sam e as, or has the sam e coeff. of expansion as, th e liquid under test.

T reatm ent of gaseous m ixtures for the purpose of separating them into their com ponents, or enriching them w ith respect to one or m ore of their com ponents. Br i t, Ce l a n e s e, L td ., D . F in -

l a y s o n, and A. J. Sh a r p ( B .P . 365,092, 15.10.30).—

Two or more gases are simultaneously adsorbed, with or without a certain amount of selection, and are then selectively desorbed by reduction of pressure. E.g., CO and IIo may be adsorbed from water-gas at about 40 atm. by activated charcoal, and then, by successive reductions of pressure, 4 fractions (A—D) may be taken : the first fraction (A) may contain 87% H a and is suitable for the prep, of NH3 after a second similar trea tm e n t; fraction B may contain 32% CO and 63% H2 and will serve for the synthesis of MeOH ; fraction C may be returned as water-gas ; fraction I) may contain 78% CO and 10% H , and, in conjunction with aliphatic alcohols, can be used for the prep, of aliphatic acids. B . M. Ve n a b l e s.

Decom position of gaseous m ixtu res. Ges. f. Li n d e’s Eis m a s c h in e n A.-G. ( B .P . 365,390, 6.3.31.

Ger., 6.3.30).—In the separation of gases b y means of alternately used cold regenerators, the cold-accumulating substance is interspersed w ith adsorption medium for separation of impurities in a zone of higher tem p, than could be used for condensation by cooling alone.

Filter for cleaning air or gases. A. ^S^{c h i r p} (B.P.

365,723, 1.12.30. Ger., 26.3.30).—The filter comprises a travelling screen moving vertically and transversely to the gases. The actual filtering material is attached to sectionalised carriers which, on the run facing the gases, abut ajid form a continuous screen moving slowly; on the other run each section falls rapidly to (or is lifted rapidly from) a cleaning bath a t the bottom.

Devices for effecting the different speeds on the different runs are described. B. M. Ve n a b l e s.

Dust separators [for g ases]. II. H. Bubar (B.P.

365,050, 13.8.30. U .S., 13.1.30).—The gas is caused to flow into a number of converging passages the vortical walls of which are composed of louvres which open in a trailing direction, permitting the gas to pass gradu

ally into zones of lower pressure in diverging passages alternating with the converging ones. The slats of the louvres are V-shaped and form traps down which the dust slips to a collecting chamber below.

Separation of suspended m aterial from gases by centrifugal action. In t e r n a t. Pr e c ip it a t io n

Co. (B.P. 365,312,12.1.31. U .S ., 8.12.30).—The separat

ing elements comprise two tubes of different diam.

partly telescoped into each other, the inlet for dusty gases being through whirl-producing vanes in the annular space. The inner tubes extend upwards beyond the outer, either right through the inlet header common to all the outer tubes, or partly through and leading into a number of outlet headers arranged in rows and spaced apart to allow for the passage of the

a 2

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B r itis h C h e m ic a l A b s tr a c ts^— B ,

294 Cl. II .—Fu e l; Ga s; Ta b; Mineral Oils.

inlet gases between. The upper ends of the outer tubes are rectangular, hexagonal, or other shape which permits them to be joined without spaces, and their lower ends are tapered and extend into a common collecting chamber for dust. B. M . Ve n a b l e s.

[Dust exclusion from roller spindles of] pulveris

ing m ills. In t e r n a t. Co m b u s t io n, Lt d., Assees. of F. H. Ro s e n c r a n t s (B.P. 364,526, 13.10.30. U.S., 11.10.29).

Mechanical separation or grading of m ixtures [refuse etc.]. Ne w De s t r u c t o r Co., Lt d., J. L.

Ba t e s, J. T. Cr a v e n, and H . M. Hu t c h in s o n ( B .P . 3 6 5 ,3 8 4 , 2 8 .2 .3 1 ).

Agitated sieves. E. ^La r s s o n and E. Pe t t e r s s o n

(B.P. 366,886, 29.9.31. Swed., 4.10.30).

COa for refrigerators.—See VII. Lehrs, anneal

ing furnaces, etc. Furnace lining.—See VIII.

II.— FU EL; G A S; T A R ; MINERAL OILS.

Colloidal dispersion of coal. J. M. Pe r t i e r r a

(Anal. Fis, Quim., 1931, 29, 663—679).—The dissolution of coal (C 79-3, II 5-14, volatile m atter 28-3%) by

N H 2P h , CgHgN, and quinoline a t the b.p. and 200°, and the influence of the duration of heating and of renewing the solvent, have been examined. By succes

sive extractions for about 6 hr. with NH2Ph, up to 72-7% of the coal enters into colloidal solution. The solution contains particles of varied sizes and behaves as a typical suspension. A similar type of suspension is obtained by the action of primary ta r on coal; it is probable th a t during berginisation the ta r initially formed disperses part of the coal and thus facilitates its hydrogenation. H. F. Gi l l b e.

Position of the gas off-take pipe in carbonisation.

G. E. Fo x w e l l (Gas J., 1932, 197, 82—86).—The resistance to the flow of gas exerted by coal, coke, and the plastic layer during carbonisation has been calc, from experimental data. I t appears th a t the withdrawal of the gas from the centre of the charge in a coke oven is possible only in the case of weakly coking coals, and even then no practical advantage is gained.

R . N . B . D . Br u c e.

Carbonisation tem perature of coal and tim e required. T. Ku r o d a and K . Ta k e i (Fuel, 1932, 11, 56—60).—The course of the carbonisation of a number of Japanese and Chinese coking coals has been followed by determining the variation with time of heating of the electrical conductivity of a small briquette of the coal contained in an electrically-heated S i02

tube. Some of the coals were preheated before being briquetted, in order to diminish their swelling power.

The results have been used to calculate the time required for complete carbonisation; the times varied with temp, of carbonisation from about 1500 min. a t 650° to about 16 min. a t 850°. With some coals the hardness of the coke produced passed through a max, as the temp, of carbonisation was raised. A. B. Ma n n i n g.

Physico-chem ical studies of different types of coking coals. B . Ro g a (Przemyśl Chem., 1 9 3 1 , 15,

2 8 1 — 2 9 4 , 3 0 5 — 3 1 6 , 3 6 2 — 3 7 9 ).—The coking properties of coal depend on its caking power, its ability to assume

the plastic state, its swelling pressure, the course of evolution of gas, and the thermostability of substances responsible for caking. Caking gas coals are unsuitable for coke production owing to the complete absence of swelling pressure rendering impossible sufficient impreg

nation of the whole mass of coal in the oven. A method for the determination of the caking power of coal has been elaborated, depending on the heating of a mixture of coal with anthracite under const, pressure. The caking properties of vitrains and durains depend on the type of coal from which they originate, but are more pronounced for durain than for vitrain taken from the same seam. Fusains have no caking properties, do not swell on heating, and do not assume the plastic state. The caking index of a coal, using various inert diluents, depends both on the nature and on the develop

ment of the surface of the diluent. The bituminous constituents of coking gas coals, to which agglutination is due, are considerably less thermostable than are the corresponding constituents of typical coking coal.

Caking gas coals exhibit max. evolution of gas not only during the period of plasticity, bu t also during the succeeding period, in which respect they differ from typi

cal coking coals. The cracks and fissures found in coke prepared from coking gas coals are to a great extent due to this phenomenon. R. Tr u s z k o w s k i.

D eterm ination of calorific value of coal. R.

Vo n d r a c e k (Chem. Listv, 1932, 26, 48).—Moravec’s remarks (B ., 1932, 87) are criticised. R. Tr u s z k o w s k i.

Influence of bitum en on the coking power of coal and m ixtu res of coals. K. Bu n t e [with W.

Morlocic] (Z. Oesterr. Ver. Gas- u. Wasserfachmannern, 1931,71, 81—90; Chem. Zentr., 1931, ii, 355).—The C, H, and volatile m atter contents of non-bituminous and 5 bituminous fractions of various coals were deter

mined. The caking power increases with diminution in particle size, and depends on the [3 and y3 and y4

bituminous fractions. The Yi and y2 fractions slightly increase, and the oc fraction diminishes, the caking power.

The caking power of coal mixtures is approx. the arithmetical mean of those of the constituents. The resistance to compression is affected by the ratio of a, [3, y3, and y4 fractions ; y3 and y4 increase it, whilst

¡3 diminishes it. A. A. El d r i d g e.

Effect of oxidation on coking properties of coal.

R. V. Wh e e l e r and T. G. Wo o l h o u se (Fuel, 1932, 11, 44—55).—Three Yorkshire coals have been carbonised at about 450° in a rotary retort, both before and after being subjected to oxidation at 200—300°. The retort, which could hold a charge of 56 lb. of coal, was heated internally by means of circulating gas : the oxidations as well as the carbonisations were carried out in the retort by suitably adjusting the temp, and passing air, or air diluted with inert gases, through the coal therein.

The results obtained, which have been confirmed by similar experiments with other coals, indicate th a t coals of lower C content, i.e., of higher O content, are more readily affected by oxidation, as regards diminution of caking properties, than are coals of higher C content.

A degree of oxidation insufficient to affect the ultimate analysis can cause a coal of low C content to lose its caking power almost completely. W ith increasing C

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C l . II.— F u e l ; G a s ; T a r ; M i n e r a l O i l s . 295

content coals become less readily oxidised and their caking power is affected only after an appreciable change in ultimate analysis has been effected. The yield of oil obtained on carbonisation is then materially reduced.

A. B. Ma n n i n g.

M echanism of coking and coking practice. P . Sc h l a p k e r (Monats-Bull. Schweiz. Ver. Gas- u. Wasser- fachmannern, 1931, [5], Reprint, 7 pp.).—The general results of experiments on the thermal decomp, of coals, the evolution of gas from semi-coke, the plastic ranges and swelling properties of coals, and the effect of thermal pretreatment on coking coals are reviewed and briefly discussed with reference to technical problems in coal carbonisation. II. E. Bl a y d e n.

Form ation of lum p coke. II. A. J. Pie t e r s (Gas- u. Wasserfach, 1932, 75, 1—7).—The factors influencing the formation of lump coke are discussed and the Gray, Campredon, Meurice, and Marshall-Bird methods of determining caking index are compared. I t is shown th a t the results of the methods are greatly influenced by the rates of heating used. Limiting-val. methods (e.g., Gray’s method) of determining caking index are to be preferred to compression-test methods [e.g., Meurice, Marshall-Bird tests) in which rapid heating of the mixtures gives good compression curves even with poorly-coking coals; but the caking index itself is no measure of the capacity of a coal to yield good lump coke. Caking power and ability to swell or exert swelling pressure arc inter-related and dependent on the softening properties of the coal. Excessive swelling of a coal may be controlled by dilution with coke or semi-coke.

Fundamental factors requiring investigation are dis

cussed. II. E. Bl a y d e n.

Calculations based on the proxim ate analysis of solid fuel. Dk Ca h i e r (Gas World, 1932, 96, 97—99).—The cokc yield can be calc, from the % of volatile m atter (7) in the dry coal by several formula ; for coals with a higher content than 26%, coke yield

= 100-5 — 0-85F. For the Gray-King high-temp.

assay, for modern coking practice, and for horizontal retorts the formulas are : coke yield = 9 0 - 5 — 0-52F, 99-1 — 0-88F, and 112-0— 1-22F, respectively.

Formulas are also given for calculating the % ash in coke, from the ash in the coal, in coking and gas-making practices. The calorific val. of coals and cokes can be calc, from their C content and proximate analyses by various formula;. C. B. Ma r s o n.

Coke in relation to its dom estic use. J. H. Dy d e

(Gas J., 1932, 197, 150—153).—Cokes of the vertical- retort type possess an open structure and low bulk density, thus conforming to an ideal open-grate fuel.

Under optimum conditions they radiate up to 40% of their intrinsic heating val. The presence of moisture is to be avoided as it decreases the ease of ignition and lowers the temp of the fuel bed. Increase of ash content from 2% to 18-5% lowers the radiant efficiency only from 37% to 32%. The behaviour of typical gas cokes in a small coke boiler was examined with regard to boiler efficiency. An optimum size (about 1 in.) for each grade is necessary for the attainm ent of max. heat transfer. Approx. 60% efficiency can be reached, the flue losses being only 15%. A fuel of high bulk density

coupled with ease of combustibility is ideal for burning in domestic coke boilers. R. N. B . D. Br u c e.

New use for low-tem perature coke. A . We b s t e r

(Chem. and Ind., 1932, 72—73).—The design and operation of a producer, using low-tcmp. coke as a fuel, which is attached to lorries and tractors to provide a motor fuel is described. C. B. Ma r s o n.

Combustion of coke in central heaters. P.

Sc h l a p f e h (Monats-Bull. Schweiz. Ver. Gas- u. Wasser- fachmannern, 1930, [2, 3]; Eidgen. Materialpriif. E.T.H., Zurich, Ber. No. 48, 32 pp.).—The fundamental factors influencing the efficiency of central-heating boilers are discussed. The effects of heating 3 types of boilers with foundry or gas coke were investigated : the resulting changes in waste-gas composition and temp., and the effects of provision of secondary air for combustion and changes of load and draft are described. The formation of slack is determined by the combined influence of ash content and m.p. of ash, coke size, and method of firing. The presence of breeze in the fuel has an un

favourable effect on heating efficiency, which is also markedly influenced by size and hardness of the coke.

Uniformity of size and ash content, hardness and reduction of breeze content of gas coke may be secured by fine grinding of the parent coal, the product being comparable in heating effect with foundry coke.

II. E. Bl a y d e n.

Determ ination of the true specific gravity of soots under different experim ental conditions.

H. J. Mü l l e r (Kautsehuk, 1932, 8, 27—28).—In apply

ing the pyknometer method to C black or lampblack, the results obtained are influenced by the liquid medium used (dekalin, xylene, or PhMe), probably on account of a variable degree of adsorption at the surface of the black and a variable degree of penetration. I t is advisable in comparative experiments to use a const, wt. of black and to assist escape of air by submitting the material to reduced pressure before and during the addition of the liquid. D. F. Twiss.

Coal enrichm ent and catalytic hydrogenation under pressure. C. Kr a u c h and M. Pi e r (Z. angew.

Chem., 1931, 44, 953—958).—Principally a survey of recent industrial research, and especially of the develop

ment of catalysts for high-pressure hydrogenation of oils which have high activity and low tendency to become poisoned. In practice, with appropriate catalysts, middle oil may be treated a t 325° without polymerisation ensuing, and the catalyst thus may be kept in use for a year or even longer. Crude benzols may be efficiently converted into motor spirit without hydrogenation of the C6H8 nuclei and consequent reduction of the anti

knock properties, and illuminating oil may be manufac

tured from lignite oils and highly-unsaturated mineral oils by treatment a t 400°. The production of benzine from oil and from coal is described in some detail, and the improvement of low grades of lubricating oil is noted. Yields of marketable benzine from lignite, coal, and tar have reached a t least 55%, 65%, and 80—85%, respectively. H. F. Gi l l b e.

Catalytic action of thallium com pounds in destructive hydrogenation. ^A^{n o n}^.(Chem. Weekblad, 1932, 29 , 42—43).—Hydrogenation of a specimen of

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B r itis h C h e m ic a l A b s tr a c ts— B .

29G Cl. IT.—Fu e l. ; Ga s ; Ta r ; Mi n e r a l Oi l s.

lignite a t an initial pressure of 1 0 0 kg./sq. cm. yielded H 20 8.7, gas 29-4, hydrocarbons (b.p. <[ 220°) 3-5, kerosene (220—300°) 3-8, cresols 2-8, residue of Engler distillation C> 300°) 12-1, residue (C) 39-7%. In pre

sence of TINOj the yields were (% ): 13-8, 30-1, 2-4, 5-7, 3-0, 28 ■ 9, and 18-8, respectively, whilst if the lignite were treated with solutions of T1N03, EOH, and II20 2, to form a deposit of T120 3, the yields were : 9-1, 34-8, 4-7, 5-9, 3-4, 37-6, and 4-5%, respectively. The low C residue in the third series may have been due in part to oxidation of the lignite by the II202 used.

II. F. Gi l i.b e.

Interm ittent vertical cham bers [for gasification of coal] : som e recent developm ents. L. II.

Se n s i c l e (Gas J., 1932, 197, 145—147, 199—200).—

The path of travel of the products of carbonisation in such chambers differs from that in continuous vertical retorts as the motion of the plastic layers is dissimilar.

In the first process a more robust coke, a better road tar, and a more normal type of benzol are produced. As smaller coal can be carbonised the net cost of a therm of gas (510 B.Th.U.) is lower (1 • 101 and 1 -S lid., respect

ively). 70% steaming efficiency is possible and produc

tion of water-gas is more economic than in an external water-gas plant. Total gasification in vertical chambers is suggested as a source of H2 for NH3 synthesis. The region of greatest coal density, when charged from above, is about- two thirds of the way down ; this has an important effect on flue design, which is discussed.

The max. swelling pressure, which influences the allow

ances made for expansion of the chamber walls, occurs about 2 hr. before the completion of carbonisation, i.e., when the two plastic layers meet. The factors governing the choice of producer plant are discussed.

R. N. B . D. Br u c e.

Gasification of low -quality fuels with oxygen and steam . M. Bo h m (Giorn. Chim. Ind. Appl., 1932, 14, 21—23).—In view of the large amounts of 02

rendered available by the synthetic NH3 process, the production of gas of good quality from coal, lignite, or wood charcoal in producers fed with 0 2 and steam is recommended. Such gas, consisting of CO and H2 in the proportions required to give MeOH, is being used in the Nat.ta process for synthesising this alcohol.

T. H. Po p e.

W ater-gas from dry-quenched coke. A. B. Wo l l e

(Gas J., 1932, 197, 252).—If moisture-free coke is used in water-gas plants, a saving of fuel is to be expected and the time of the “ blow” period is reduced. The amount of fuel saved is calc, to be about 1% of the fuel for each 1% reduction in moisture content. Actually a full-scale test showed th a t a 6% saving on fuel was obtained by using dry-quenched coke ; other advantages are its freedom from surface dust and th a t it permits the use of a smaller fuel. C. B. Ma r s o n.

Purification of town gas by m eans of iron oxide.

J. Dr e v e r m a n (Gas J., 1931, 193, 97—100).—A survey of Fe oxide purification as practised in Australia is made. Analyses show th a t the local natural oxide is better than that in use in England, especially in fineness and Fe content. A 1 : 2 mixture of fresh oxide and sawdust gave optimum results, removing nearly its own wt. of impurity, and is also easier to handle and dis

integrate. The crude coal gas contained 180—230 grains H 2S per 100 cu. ft. and was allowed to retain 10—20 grains NH3 at the purifier inlet. The average working temp, of the boxes was high, i.e., 51-7° ; 7 cu. ft. of oxide vol. was allowed for each 1 0 0 0 cu. ft. of gas.

R . N. B . D . Br u c e.

Purification of gas [by low-tem perature cooling].

Le n z eand Re t t e n m a i e r(Gas J., 1932,197,139—142).—

The hot crude gas, after passing through the atm.

condensers, is washed and cooled to 2-2° by a spray cooler and then treated direct with dil. aq. NH3 a t 5° ; the gas then has a dew point of 0°. The amount of fresh H2 0 necessary is 187—312 gal. per 1 0G cu. ft. of gas. The necessary cold is produced by N il, refrigera

tion ; the power required may be obtained from the sensible heat of the crude gases leaving the retort.

A description of such a plant, producing conc. NH3

liquor, is given. The quantity of heat removed in cooling 1 cu. ft. of gas from 25° to 0° is 2450 B.Th.U.

The purified gas contains 8 grains of NH3 and 4—12 grains of C10II8 per 1000 cu. ft. ; the cost of operation is 0-28d. per 1000 cu. ft. This process, which gives an unusually pure gas, is useful when long-distance high- pressure mains are employed. R . N. B . D, Br u c e.

Naphthalene rem oval [from coal ga s]. B . Th o r p e

(Gas J., 1932, 197, 196—198).—CI0H8, benzol, and gum-forming hydrocarbons are removed simultaneously from coal gas by washing with gas oil. Regeneration of the oil by steam results in the recovery of 0*375 gal. of benzol and 0-277 lb. of C10Hg per ton of coal carbonised.

The mechanism of the formation of gummy deposits on meters, valves, etc. is discussed. R. N. B . D. Br u c e.

Rendering gas non-toxic b y bacterial m eans.

W. Be r t e l s m a n n (Gas- u. Wasserfach, 1932, 75, 130—

132).—CO present in gas is converted by the bacteria in sewage into C02 and H 2, which react further to form CH4 ; 4 vols. of CO afforcf 1 vol. of CII4 and 3 vols. of C02. Oil this basis, a coke-oven gas containing 5-4%

CO should be increased in calorific val. from 4364 to 5684 kg.-cal. per cu. m. ; the actual experimental val.

obtained (cf. B ., 1930, 803; 1931, 186) was 4948.

Respective contractions in vol. after correcting for N2

coming from the sewage are 27-7% and 32% ; the net calorific vals. are 4110 and 3083 kg.-cal. per cu. m.

The gas production to obtain an equal thermal yield must therefore be increased 1-32 times, and the ground space necessary for bacterial purification is calc, to be

8 8 times th a t for the removal of S by the oxide process.

R." N. B . D. Br u c e.

Controlling pressure conditions w ithin coal-gas retorts. R. N. We b b (Gas J., 1932, 197, 87—89).—

A const, internal pressure of in. water-gauge main

tains leakage through the retort wall at a min. This is shown by low N2 content of the gas, and an approach to the theoretical amount of C02 (20-35%) in the air- free waste gases. Raising the pressure to 1 in. results in serious leakage, which disappears with correct pressure control. R. N. B . D. Br u c e.

Exhausting and governing gas from retorts.

R. Summerson (Gas J., 1932, 197,311—314).—Measure

ments of pressure in the fcail main, off-take pipes, and retort mouthpieces have been made under varying

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B r itis h C h e m ic a l A b s tr a c ts — B .

Gl. I I .—Fu k lj Ga s ; Ta b ; Mi n b b a l Oi l s. 297

conditions of carbonisation. Their application to the design of a sensitive governor is discussed.

R. N. B . D . Br u c e.

Internal corrosion of gas m ains. K. Bu n t e and P. S tru c k (Gas- u. Wasserfach, 1 9 3 2 ,75, 87—8 9 ).—The former opinion th a t if debenzolisation is not performed the gas mains are protected by an oily layer has been controverted by Ott, who considers that the adverse action of aq. condensate is at least as effective. The evidence is th at rust formation commences in the usual way by the action of 02 and H20. I t is then promoted by the presence of C02, IICN, H2S, and NH3. A series of analyses of rust from mains showed Fe2035 0—8 0 % ,

Fe4[Fe(CNjg]3 6— 1 6 % , NH3 0 - 6 — 1 - 5 % , and S up to 3 3 % . These figures and an examination of the deposit showed th at in many cases the S removal was far from complete. To minimise corrosion it is desirable to dry the gas and maintain the 0 2 content below 0-5%.

The good working of the NH3 and S purification plant is

also important. C. Irw in.

C atalysts for high-pressure hydrogenation of phenols and hydrocarbons. H. Tr o p s c i i (Fuel, 1932, 11, 61—66).—The destructive hydrogenation of a gas oil a t 440° under a max. II2 pressure of 200 atm. has been carried out in a 450-c.c. rotating autoclave in the presence of catalysts, especially those which had previously proved effective in the hydrogenation of cresol (B., 1931, 194). The most efficient were MoS3, (NH4)2MoS4, and WS3, which gave about a 50% conver

sion of gas oil into light oil (b.p. <[ 230°); with MoOa, however, the yield of light oil was no greater than in the absence of a catalyst (21%). MoS3 also proved an excellent catalyst for the destructive hydrogenation of paraffin wax, giving not only a doubled yield of light oil (46% of the original paraffin wax), but also complete hydrogenation of the cleavage products formed.

A . B . Ma n n in g.

Solvents from the gas industry. C. R. Do w n s

(Chem. and Ind., 1932, 28—33, 45—49).—Works methods for fractionation of coke-oven and coal-tar light oils and testing for colour, density, boiling range, H2S 04 wash, acidity, solidifying point, limpid point, separable C10I i 8, gumming, and corrosion arc described.

The tests of 30 solvents ranging from C6H8 to heavy solvent naphthas are tabulated and their relation to the composition and uses of the solvents is discussed. The rates of evaporation of 18 solvents and 1 0 mixtures are compared with those of E t20, COMe2, CS2, CHC13, CC14, EtOAc, EtOH, BuOAc, (yi^-O A o, BuOH, turpentine, and kerosene. No standardised evaporation test has yet been devised. C. Ho l l i n s.

Asphalt penetrom eter. A. Wo l f (J. Sci. Instr., 1932, 9 , 22—24).—The needle of the standard .type is replaced by a rod, and higher loads and longer contact periods are used. Conditions of use are described,

C. W. Gi b b t,

Action of volcanic ash on oils. Origin of Japanese petroleum . T. Te r a d a, M. Hi r a t a, and T. Ut i o a s a k i (Sci. Papers Inst. Phys. Chem. Res., Tokyo, 1932,17, 265—293).—A variety of oils have been distilled over volcanic ash and over pumice. In general, the distillates resemble kerosene in physical properties,

but contain considerable quantities of unsaturated compounds. I t is suggested th at Japanese petroleum has been produced from animal or vegetable oils in a

similar manner. R. Cu t h i l l.

Som e properties and com positions of the g aso  line fractions of representative Japanese crude petroleum s. M. ^M^{iz u t a} (J. Soc. Chem. Ind., Japan, 1931,34-, 489—490 b).—Equations are given representing the relation between the NH2Ph-point depression and the contents of CeH6, PhMe, and xylene in straight-

run gasolines. D. K. Mo o r e.

Therm al expansion of gasolines from 0° to 30°.

C. S. Cr a g o e and E. E. Hi l l (Bur. Stand. J. Res., 1931, 7, 1133—1145).—Results obtained from cracked motor fuel with and without benzol additions indicated that their thermal expansion is greater than the vals.

previously based on straight-run petrol. On a utility basis, motor fuels may be divided into two classes with an average volatility range of (a) 80—110°, and (6) 110—140°, having respective coeffs. of expansion of 0-00068 and 0-00062 per ° F. Corrections for thermal expansion of petrols may be made more accurately on the basis of volatility rather than of sp. gr.

C. A. Ki n g.

Oxidation m echanism of m ineral oils. T.

Ya m a d a (J. Soc. Chem. Ind., Japan, 1931, 34, 493—

495 b).—Oxidation of mineral oils both in open and closed vessels at 120°, in the presence of CaCl2, causes the product to have lower sap., acid, and Ac vals. than those of such oils oxidised without adding CaCl2. At

1 0 0° CaCl2 in contact with the oil accelerates, whilst P205 and KOH retard, 02 absorption. The presence of these substances in the atm. above the oil causes the apparent absorption of 0 2 to be more rapid, but the products have lower sap. val. than when such absorbents are absent. H 20 seems to aid the formation of acidic

substances. D. K. Mo o r e.

Separation of [substituted] thiophens from oils containing sulphur. Le c l e r e and [Mm e.] Le c l e r e

(Compt, rend., 1932, 194, 286—287).—Treatment of such oils with 96-5% H2S 04 in cold ligroin for 1 hr.

sulphonates alkylthiophens, but not hydrocarbons.

Boiling H 20 regenerates the thiophens from the sulphonic acids. In this way the oil from bituminous rocks yielded 2- and 3-isopropylthio'phen, b.p. 153—154°

and 157—158°, respectively. R. S. Ca h n.

Lubricating oils w ith colloidal adm ixtures.

0. St e i n i t z (Allgem. Oel- u. Fett-Ztg., 1932,29, 35—37).

—At high speeds the effect of adding, e.g., 2% of colloidal graphite is not very noticeable, but a t low speeds, and especially in conditions of imperfect lubrication, im

proved lubricating power is evidenced in reduced fric

tion, lower bearing temp., and better adhesion of the oil film. Practical machine tests confirm these results.

E. Le w k o w i t s c h.

Determ ination of alcohol and benzene in m otor fuels. H. Bil g r a m (Woch. Brau., 1932,49, 15—16).—

Even small amounts of EtOH can be detected by shaking about 50 c.c. of the fuel in a well-stoppere'd vessel with four strips of Dracorubin paper (Chem.

Fabr. Helfenberg). The paper is decolorised and the liquid coloured red. In C-Hg-petrol mixtures this occurs,

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2 9 8 C l . I I . — F u e l ; G a s ; T a r ; M i m b r a l O i l s .

and then but slowly, only when the C0H8 exceeds 70%.

For quant, analyses, the EtOH is removed by shaking out with saturated CaCl2> and the residual hydrocarbon mixture determined by vol. A test is set up on this with Dracorubin paper, simultaneously with a set of similar tests on C6H8-petrol mixtures of known com

position, with which it is compared colorimetrically after

keeping overnight. F. E. Da y.

Determ ination of benzene in w ater. H. A. J.

Pi e t e r s (Chem. Weekblad, 1932, 29, 72—73).—A large vol. of the H 20 is shaken with 5 c.c. of CC14, and the increase in vol. of the latter determined after settling.

S. I. Le v y.

Crystallisation of paraffin w ax. II. E. Ka t z (J.

Inst. Petroleum Tech., 1932, 18, 37—52 ; cf. B., 1931, 329).—Above a “ temp, of change ” (definition given) which is 5—7° lower than the m.p. of the wax for hard and medium waxes, and 1 0° lower than the m.p. for soft waxes when the solvents are lubricating oils, kero

sene, CgHg, CC14, and a little higher when P hN 02 and

»i-cresol are used, solutions of paraffin wax deposit needle-shaped crystals, and below it, provided the solution has not initially deposited needle crystals, plate crystals. A solution which has initially deposited needle crystals will continue to do so a t temp, much below the temp, of change even if the crystals already formed are removed from the motlier-liquor ; it is only when the solution is cooled to 12—14° below the temp, of change and the crystals are removed th a t the mother-liquor deposits plate crystals on further cooling. I t is suggested that variation of the concn. of the different components of the wax during crystallisation may affect the develop

ment of particular crystal forms. D . K . Mo o r e.

Constitution of coal. F. S. ^Si n n a t t (Proc. S. Wales Inst. Eng., 1932, 47, 793—825).

Turbo-com pressors as used in coke-oven plants.

F. We i n r e b (Gas W o r ld , 1932,96, C o k in g Sect., 34—37).

Higher alcohols from carbon m onoxide and H 2, Naphtlienic acids.—See III. O il-w ell cem enting.

—See IX. Corrosion of Pb.—See X. Lubricating oils.—See XII. Scorch retarders for rubber.—

See XIV.

Pa t e n t s.

Carbonising processes. W. E. Tr e n t(B.P. 305,694, 11.11.30).—The fuel to be carbonised is charged into containers which are carried through a distillation chamber by means of an endless conveyor. Each con

tainer has a bottom pocket constituting a receiver for a heat-storage element composed, e.g., of cast Fe. These elements, heated in a furnacc to a sufficiently high temp, to effect the required degree of carbonisation, are intro

duced into the containers just before they pass into the distillation chamber. A. B. Ma n n in g.

Horizontal regenerative cham ber ovens for pro

duction of coke and gas. C. St i l l (B.P. 364,943, 20.3.31. Ger., 22.3.30).—Four regenerative chambers are arranged in parallel in each half of the substructure of the oven, extending in the form of tunnels over the whole length of the battery. The two pairs of chambers adjoining the outer walls of the oven battery are adapted for preheating gas for combustion or selectively either

gas or air, whilst the other pair of chambers are used exclusively for preheating air. Between or a t the sides of the chambers are load-supporting walls.

A . B . Ma n n in g.

Apparatus for treatm ent of coals, tars, mineral oils, and the like w ith hydrogen. ^{J .} Y. ^Jo h n s o n.

From I. G. Fa r b e n i n d. A.-G. (B.P. 3 6 5 ,6 1 9 , 2 5 .9 .3 0 ).—

The reaction vessel etc. is constructed of or lined -with, a material, e.g., an alloy steel containing Cr, V, or Al, etc., which is coated internally with a thin layer of Si, Al, or other material which is stable to corrosion by S or its compounds. A. B. Ma n n i n g.

Manufacture of carbon from acetylene. W. W.

Gr o v e s. From I. G.' Fa r b e n i n d. A.-G. (B.P. 3 6 4 ,7 5 7 , 1 7 .1 1 .3 0 ).—About 1 vol.-% of a metal carbonyl vapour is added to C2H2 and spontaneous decomp, of the mix

ture is initiated by exposure for a short time to an electric spark or incandescent filament. The yield of finely-divided C is 9 0 — 1 0 0 % of theoretical.

A. B. Ma n n i n g.

T reating light ashes for activating the carbon therein. W. W. ^G^{r o v e s}^. From A.-G. v. St ic k s t o f f d ü n g e r (B.P. 3 6 5 ,6 8 5 , 6 .1 1 .3 0 ).—The light ashes carried from the furnace by the flue gases in the combustion of lignite, brown coal, etc. are heated with an activating agent, e.g., alkali carbonates, and, if desired, in the presence of air or I I20 etc., a t about 1 0 0 0° ; a highly active C is produced. A. B. Ma n n i n g.

Preparation of colloidal [graphite] suspensions in o ils. Ei n s t e i n’s El e c t r o Ch e m. Pr o c e s s, Lt d., a n d E . Ha t s c h e k ( B .P . 3 6 6 ,1 2 8 , 3 0 .1 0 .3 0 ).— F in e ly - g r o u n d g r a p h i t e is m ix e d w i t h a n a q . s o l u t io n o f N a o r K o le a tc o r r e s i n a t e a n d t h e r e s u l ti n g p a s t e is s u s p e n d e d in I I 20 . W h e n t.hc n o n - c o llo id a l p a r ti c l e s h a v e s e t t l e d o u t t h e s u s p e n s io n is t r e a t e d w i t h a p r e c i p i t a n t f o r t h e s o a p ,

e.g., H C 1, C a C l2, o r A12(S0.1)3, a n d t h e c o a g u lu m o b t a i n e d is t h o r o u g h l y w a s h e d a n d h e a t e d w i t h a v e g e t a b l e o r h y d r o c a r b o n o il u n t i l t h e H 20 is e x p e lle d a n d a c o llo id a l d is p e r s io n c o n ta i n in g 1 0 — 1 5 % g m p li i te is o b t a i n e d .

A . B . Po w e l l.

Manufacture of producer gas. F . A . F . Pa l l e- m a e r t s, a n d Un io n Ch i m. Be l g e Soc. An o n. ( B .P . 3 6 5 ,5 5 4 , 2 0 .1 0 .3 0 ).— A c o n ti n u o u s p r o c e s s f o r p r o d u c in g a r i c h g a s (1 0 0 0 — 3 0 0 0 k g .- c a l./c u b . m .) c o n s is ts o f a d m i t t i n g a m i x t u r e o f s t e a m a n d a g a s r i c h i n 0 2 i n t o a p r o d u c e r , t h e % o f 0 2 in t h e g a s b e in g a u t o m a t i c a l l y m a i n t a i n e d c o n s t ., a n d t h e a m o u n t o f s t e a m b e in g s u f f ic ie n t to r e d u c e t h e t e m p , in t h e p r o d u c e r b e lo w t h e m .p . o f t h e f u e l a s h . A . B . Ma n n in g.

Production of non-poisonous town gas. H. Co h n

(B.P, 3 6 5 ,9 0 2 , 2 0 .4 .3 1 ).—Gases containing H2 and CO

are freed from the latter by the conversion of part of it into CH4, by interaction with part of the H 2, followed by the conversion of the remainder into H2 and C 0 2,

by interaction with the H 20 formed in the first reaction.

The reactions are cariried out in the presence of suitable catalysts, e.g., Ni a t 3 0 0 ° for the first, and Fe203 at

5 0 0 ° for the second. A. B. Ma n n i n g.

Manufacture of com bustible g a s rich in hydrogen.

Hu m p h r e y s & Gl a s g o w, Lt d., Assees. of H . G . Te r z ia n

(B.P. 3 6 5 ,9 1 2 , 3 0 .4 .3 1 . U.S., 3 0 .4 .3 0 . Cf. B.P. 3 1 9 ,7 6 9 ; B., 1 9 3 0 , 9 3 7 ).—Hydrocarbon gases are cracked to C