British Chemical Abstracts. B.-Applied Chemistry. April 11 and 18

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A P R IL 11 and 18, 1930 *


Production of electrical energy in chemical plant w ithout cost. H. Wo l l e n b e r g (Chem.-Ztg., 1930, 54, 9).—W aste water from several coolers etc.

positioned a t a height is caused to operate a turbine on falling to the ground level. S. K. Tw e e d y.

Removal of dust and sulphur acids from power- station w aste g ases. I. M ethods of separation in actual u se. II. M ethods and apparatus for gas purification em ployed in the chem ical and m etall­

urgical industries. III. Recent patents and pro­

cesses for cleaning ch im n ey gases. J. B. C. Ke r­ s h a w (World Power, 1929, 12, 533—536; 1930, 13, 15—19, 164—165).—I. As an indication of the total amount of solid m atter discharged into the atmosphere from modern power stations, it is observed that 8—11% of the fuel weight is the average collected in the grit catcher. Dry catchers associated with the fan, e.g., Sturtevant, Davidson, and “ Pncuconex,” and the Rowntree water-spray plant are described.

II. Sulphur compounds are removed from gases by some means of washing, and various typo of washing towers are noted. In the metallurgical industries, dry methods, e.g., Halberg-Beth and Lodge-Cottrell, are generally used for removing dust.

III. Recent patents are described, including Baron’s method (cf. B.P. 314,110 ; B., 1929, 741) now installed at an electricity works in London. C. A. Ki n g.

Absorption of g a ses and im purities in air under pressure. A. Ba r t h (Chem.-Ztg., 1930, 54, 143—144).

—The removal of such constituents as ammonium chloride vapours, silicon fluoride, hydrofluoric acid, etc.

from the exit gases of chemical works by absorption in water is greatly facilitated by carrying out this operation under pressure. A pressure of only 50—100 mm. of water has a markedly favourable effect on the absorption, and a description is given of a plant of this type suitable for use in technical practice.

H . F. Ha r w o o d.

M oisture in technical g ases. I. Principles of calculation. F. Lu t h (Arch. Eisenhiittenw., 1929—

1930, 3, 397—405; Stahl u. Eisen, 1930, 50, 169—

170).—Mathematical. Equations are derived and curves given for calculating the weight of water vapour in a given volume of air of known hum idity a t N.T.P. and for calculating the volume of dry gas from th a t of the

wet gas. A. R. Po w e l l.

[Calculation of tanks for high tem perature and pressure.] J. S. Th o r p (Chem. Met. Eng., 1930, 37, 107).:—In the expression given by Wood (B., 1930, 123) the term 3D should be replaced by D/3.

Centrifuges. Ve n z k e.-— S e e II. [Filters for] caustic slud ge. Lo r e n z.—See V . H igh-pressure com pres­

sors. Bl a u.—See VII.

Pa t e n t s.

Furnaces for liquid, powdered, or gaseous fuels.

Si e m e n s-Sc h u c k e r t w e r k e A.-G., ¡Assees. of K . A.

Ma y r (B.P. 298,161, 3.10.28. U.S., 4.10.27).—In a boiler furnace with water-walls constructed of spiral tubes it is difficult; to find room for secondary air inlets through the walls. In this invention the upper closure of the radiating or final-eombustion chamber is formed as a pre-combustion chamber lined with refractory material, through the walls of which the fuel is admitted in two or more streams which clash, and the air axially, tangentially, and radially. B. M . Ve n a b l e s.

[Apparatus for] com bined heat and pressure treatm ent of m aterials, particularly solid or liquid carbonaceous m atter. M . McGu i n n e s s (B.P. 324,692, 2.10.28).—A pressure- and heat-resisting vessel suitable, e.g., for the hydrogenation of oil or coal, is constructed of several co-axial shells in the spaces between which the pressure rises in steps. The innermost vessel is sur­

rounded by a lxeat insulator which may be the gaseous pressure-resisting medium, alone or with a material such as asbestos. Each shell is supported on the next through the medium of rollers, and all pipes and manholes are in the same end so th a t the shells may expand inde­

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

Operation of steam -heated dryers and apparatus therefor. Ge w e r k s c h a j t Gu s t a v, and 0 . Ao c k e r b l o m

(B.P. 324,635, 25.10.28).-—In a steam-heated dryer means are provided by which the pressure or temperature of the steam, the rate of supply of material, and the speed of rotation of the dryer are directly and auto­

matically varied by the moisture content of the material, but the quantity of steam is not directly varied by a throttle valve owing to the risk of uneven heating by incomplete filling with steam. The amount of steam flowing into the apparatus is a measure of the moisture in the in-going material, so the primary control device may be a Venturi throat in the steam-pipe. Alterna­

tively, the control may be regulated by the moisture in the out-going material, in which case a hair hygrometer may form the sensitive device. I t is preferable th a t there should be lag between the controls affecting the supply of material and steam pressure, the former being reduced before the latter is increased. The steam a t variable pressure may be obtained from a “ pass-out ” or “ back­

pressure ” turbine, or boiler steam may first be used in devices such as briquette presses or pumps.

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

* The rem ainder of this set of A bstracts will appear in next week’s issue.


B ritish C h em ical A b s tr a c ts —B-

303 C l. I .— Ge n e r a l ; Pl a n t ; Ma c h i n e r y.

H eat-exchanging apparatus. E. Ha b e r (B.P.

324,940, 3.9.28).—One of the fluids is maintained in continuous circulation by means of a propelling device, and fresh medium, e.g., combustibles, is added to the circuit and withdrawn after use through conduits which are situated in such a relation to restrictions in the circuit th a t circulation is aided. The apparatus is stated to be suitable for the combustion of powdered fuel.

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

D istillation of norm ally solid substances. R. W.

Ja m e s. F r o m Na t. An i l i n e & Ch e m. C o ., In c. (B.P.

324,840, 4.3.29).—T h e v a p o u r s l e a v i n g a v a c u u m still

f o r d i s t il l in g the m a t e r i a l a r e c o o le d t o a t e m p e r a t u r e a b o v e t h e m .p . o f t h e p r o d u c t , a n d t h e l iq u i d a n d u n ­ c o n d e n s e d g a s e s ( a ir le a k a g e ) a r e w i t h d r a w n t o g e t h e r t h r o u g h a wet v a c u u m p u m p w h i c h d is c h a r g e s th e m u n d e r a tm o s p h e r i c p r e s s u r e i n t o a s e p a r a t o r . A l t e r ­ n a ti v e ly , t h e l iq u i d a n d g a s e s p a s s i n t o a s e p a r a t o r f ro m w h ic h t h e p u m p r e m o v e s o n l y t h e g a s e s , a q u a n t i t y o f t h e p r o d u c t liq u e f ie d b y h e a t , o r o f a s o l v e n t f o r the

p r o d u c t , flo w in g a r o u n d a s e p a r a t e c i r c u i t t o a c t as

t h e s e a l f o r t h e p u m p . T h e t r e a t m e n t o f s u c h s u b s ta n c e s a s n a p h t h a l e n e , p h t h a l i c a n h y d r i d e , a n t h r a c e n e , a n d

p - u a p h t h o l is i n d i c a t e d . L . A . Co l e s.

Vaporisers. Br i t. Th o m s o n- Ho u s t o n Co., Lt d.,

Assees. of P . P . Al e x a n d e r ( B .P . 315,723, 16.7.29.

U.S., 16.7.28).—A vaporiser suitable for producing a reducing atmosphere in the process of arc-welding and similar purposes comprises an electric heater surrounded by a spiral baffle upon which the liquid, e.g., methyl alcohol, is dripped under control of a needle-valve.

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

Conveying m aterials in bulk by m eans of com ­ pressed air. ( Si r) G. C. Ma r k s. From G. Po l y s iu s

(B.P. 324.392, 25.10.28).—The material is fed into the conveying pipe by means of a number of pressure vessels which are alternately filled and emptied : during the emptying period the vessel is under air pressure, derived from the conveying pipe, from the air supply pipe, or from a separate source. When the vessel becomes empty there is a sudden drop in pressure, and this fluctuation is made use of to change over to another vessel.

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

Pulverising m ills. P . Le g r a n d (B.P. 312,047, 25.3.29. Austr., 18.5.28).—A high-speed pulveriser is provided with grinding rings which surround all the hammers, and the fineness of grinding is regulated by axial adjustment of the rings. Several methods of effecting this adjustm ent are described.

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

Process and apparatus [colloid m ill] for prepara­

tion of sem i-colloids and uniform colloids. H . E .

Po t t s. From H . Pl a u s o n (B.P. 324,977, 8.11.28).—

The material is subjected to successive crushing and disintegration in the same apparatus, which comprises a number of gear wheels in mesh performing the crush­

ing between their teeth and flinging the material against a surrounding serrated surface, which may be either stationary or consist of other gear wheels. The ground material may subsequently pass through a slowly rotating centrifugal separator which returns coarse particles to be re-ground. B. M. Ve n a b l e s.

Grading and separation of granular m aterials.

J. Lo r d (B.P. 324,469, 1.12.28).—In an apparatus

where a substantially horizontal current of air passes across a number of collecting hoppers in succession and blow's the particles into the different compartments according to their wreight and surface area, arrangements such as the use of louvres are made to vary the direction of the air current a t the line where the feed-stream enters, also between th a t point and the outlet. The exhaust air may return through an expansion chamber to the fan. B. M. Ve n a b l e s.

Apparatus for m ixin g m eal or powder with finely-divided liquids or ga ses. E . Ma h l k u c h (G .P .

459,832, 20.6.26).—The powder is fed by gravity through a hopper into a mixing chamber where it meets a stream of compressed air. This, in turn, blows it in a finely- divided form into a spray of gas or liquid supplied from a pipe controlled by a valve operated by the weight of the solid so th a t when the hopper is empty the valve automatically closes. A. R. Po w e l l.

[Vapour com pression] evaporating plants. A.-G.

Br o w n, Bo v e r i & Co. (B.P. 315,717, 16.7.29. Ger., 16.7.28).—An evaporating plant having a heat pump is initially heated up, without the use of any external apparatus or source of heat, by operating the pump to compress air wliich is circulated between the heating coils and vapour pump. B . M. Ve n a b l e s.

Separation of sa lts or other solid s from solutions thereof. [Spray dryer.] R. H. Wh e e l e r ( B .P . 324,331, 17.10.28).—A solution which it is desired to evaporate completely with formation of granular solid particles is sprayed into a con- or counter-current of air. The size of drops, distance they have to fall, temperature, and quantity of air, are all regulable to obtain the desired effect. The size of drops may be pre-determined by the size of jets and/or the head under which the solution is supplied to them. The apparatus described comprises an inner, vertical, evaporating chamber sur­

rounded by an annular chamber for gases only, and pro­

vision is made for admitting the gases to either end of the evaporating chamber in a whirling manner. The sprayer may, if desired, spray upwards and its position may be varied, or it may even be placed near the bottom of the chamber. B . M. Ve n a b l e s.

Production of film s. W . H. Pe a s e ( B .P . 324,694, 22.10.2S).—Material in the form of a very thin sheet is prepared by evaporation of a solution which has been spread in a thin layer on a conveyor belt, preferably a metallic band, which is itself heated and runs through casings which are heated, provided with means for removing air, and heat-insulated. At least one of the drums round which the belt runs is cooled and the finished film is stripped from the belt while on th at

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

F ilte rs . J. A. Pic k a r d ( B .P . 324,924. 1.8.28. Cf.

B .P . 312,944; B ., 1929, 627).—A filter of the type in which the passages for the flow of liquid become narrower in the direction of travel is constructed of a number of superposed sheets of wire gauze through which the fluid passes perpendicularly ; the diminishing apertures are obtained by varying the number of meshes and/or the


B ritis h C h em ica l A b s tr a c ts —B .

Cl. I .— Ge n e r a l ; Pl a n t ; Ma c h i n e r y. 307

diameter of the wires, and a filter aid may be used or

not. B. M. Venables.

Filter for com pressed air. Br a u t e c h n i k Ge s.m.b.H . ( G .P . 459,658, 15.4.26).—The air passes through a spiral space formed between the turns of a cooling-worm surrounding the filter drum, whereby moisture and oil are condensed, thence through a coke filter into a space below the filter drum, and finally upwards through adsorptive carbon or silica gel contained in the body of the drum between two perforated plates, the upper of which is covered with cotton wool to prevent the filter material being blown through. A. R. Po w e l l.

Internal heating of vacuum filter dru m s. R. Wo l e

A.-G. (G.P. 459,044, 28.5.25).—Steam-heated chambers are provided below and around the individual cells of the drum and are interconnected with one another and with a common source of steam supply a t one side of the

drum. A. R . Po w e l l.

P resses for extracting liquids from solid m ate­

rials. P. A. H. Vi l l e z (B.P. 312,906, 27.4.29. Fr., 2.6.28).—The material is fed through a tapering, flat, nozzle to a pair of slow-speed rollers by means of a screw-conveyor. The last is provided with a device to prevent slip, comprising a disc with notches on its edge which intercalates with the threads of the screw. The diameter of the pressure rollers is 4—6 times th a t of the screw, so as to maintain the angle of nip between 70° and 80°, and the speed of the rollers is not greater than 2 r.p.m. B. M. Ve n a b l e s.

Apparatus for straining flu ids. F. Ba i l e y and F. H. Ja c k s o n ( B .P . 324,398, 26.10.28).—In an appar­

atus as described in B . P . 246,551, in which sectors of straining material are supported between the spokes of a wheel, the sectors are composed of accordion-pleated gauze or of corrugated perforated sheet metal, and are supported between radial bars which have V-notches corresponding to the corrugations. In the event of the strainers being double (coarse and fine), flap valves are provided on the inlet side through which trapped material is released when the sector concerned is subjected to

•cleansing by back-flush. B . M. Ve n a b l e s.

Preparation of em u lsio n s. R. Au e r b a c h and W. St e i n h o r s t (B.P. 325,033, 28.11.28).—The liquid forming the continuous phase is pu t into rapid rotation, e.g., in a centrifugal pump, and the other liquid is admitted to it through a nozzle situated, e.g., on the axis of the pump a t the centre of the vortex formed in the first liquid. The interior of the pump casing may be provided with disintegrating pins. B. 'M. Ve n a b l e s.

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

317,761, 19.8.29. Swed., 21.8.28).—A liquid-tight and detachable collecting dome for a centrifugal separator is attached to the body and to the outlet pipe in such a way th a t differential swelling of the packings may take place without affecting the tightness of the joints.

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

Centrifugal m achines or separators. Ra m e s o h l

& Sc h m id tA.-G. (B.P. 310,544, 26.4.29. Ger., 27.4.28).—

A construction of hinged lid, containing the collecting vessels, and detachable outlet pipes is described for a gas-tight centrifugal machine. B. M. Ve n a b l e s.

Centi'ifugal separator bowls. Ak t i e b. Se p a r a t o r

(B.P. 316,181, 11/7.29. Swed., 24.7.28).—A centrifugal bowl having outlets for the continuous discharge of both lighter and heavier constituents, especially suitable for cases where the solid m atter is present in the lighter constituent, is provided with guides over which the lighter constituents issuing from the separating chamber pass inwardly over the outside, then outwardly over the inside, the- result being th a t the final discharge is a t a radius greater than th a t of the actual collecting zone, thus giving a steep slope upon which solid particles are unlikely to accumulate. B. M. Ve n a b l e s.

Cleaning of centrifugal bow ls. Ak t i e b. Se p a r a t o r

(B.P. 310,418, 23.4.29. Swed., 25.4.28).—The solid matters are caused to deposit on a lining of flexible material which may be slit radially and provided with handles to permit easy removal. B. M. Ve n a b l e s.

Method and apparatus for selectively discharg­

ing liquids according to their electric conductivity, particularly applicable for selecting pure water from w ater of condensation and returning it to boilers. Pa p e t e r i e s Na v a r r e ( B .P . 305,163, 7.12.28.

Fr., 1.2.28).—The electrical conductivity of the con­

densate is used to determine whether successive batches may be used or must be run to waste. A closed vessel is filled and emptied through a two-way valve, the position of which is determined by a float in the vessel; the emptying branch is connected to another two-way valve, the position of which is determined by the P.D.

between electrodes immersed in the liquid and controls whether the liquid will be used or wasted. In the event of failure of any p art of the mechanism, safety is ensured by causing the first valve to stop in the mid-position, or the second valve in the waste position. Steam or other gas pressure may be used to force the water back into the boiler directly ; if the valve is in the waste position this pressure is cut off. B . M. Ve n a b l e s.

Compound for use as w ater softener. G . R . Br u t o n ( B .P . 325,099, 12.2.29).—A mixture of equal parts of soda ash, “ Crex ” (sodium carbonate and bicar­

bonate), and powdered borax is claimed.

H . Ro y a l-Da w s o n.

E xotherm ic catalytic gas reactions. H . Ha r t e r

(B.P. 325,028, 24.11.28).—In a reaction vessel, a heat- insulating cylinder is placed between the reaction chamber and the outer pressure-resisting cylinder. The gas for the reaction is passed through the space between the insulator and the outer wall, while a separate current of cooling gas is circulated, by a pump, through the space between the insulator and the reaction chamber, through a cooler, and back again, the circulation being controlled by the pump independently of the amount of gas subjected to the reaction. The circulating current may be split off from and rejoin the incoming gas, or may be entirely independent; even in the latter case it is preferably of the same composition and a t the same pressure. " B. M. Ve n a b l e s.

Apparatus for conducting catalytic gas reactions under p ressure. No r s k Hy d r o- El e k t r i s k Kv a e l- s t o f-A ./S . (N.P. 43,725, 4.2.26).—The apparatus com­

prises a pressure vessel containing several concentric


B r itis h C h em ica l A b s tr a c ts —B .

3 0 8 Cl. I I . — Fu e l ; Ga s ; Ta r ; Mi n e r a l Oi l s.

contact chambers separated by empty annular chambers.

The gases enter the vessel a t the peripher}' and traverse alternately the contact chambers and the annular

chambers" A. R. Po w e l l.

Revivification of adsorptive m aterials. N. V.

Mo n taa x Me t a a l h a n d k l, Assees. of H. Sie g e n s ( G .P .

459,316, 24.11.22).—The material is heated by electrical resistance to expel adsorbed gases or vapours, with or without a treatm ent with another gas or vapour, e.g., air or steam. The resistor may consist of the substance itself, or with the addition of a more conductive material, or after suitable chemical treatm ent to increase its conductivity. Alternatively, a resistor element may be embedded in it. A. R. Po w e l l.

M easurem ent of the quantity of a gas or liquid p assin g through a tube. S. L ö f f l e r (Austr.P.

109,123, 27.8.25. Ger., 28.8.24).—The movement of the liquid or gas through the tube lifts a conical valve from its seating, and this motion is communicated by a thread to an iron balance weight moving in an induction coil. An indicator device working on an electromagnetic principle records this motion.

A. R. Po w e l l.

M eans for m aintaining constant pressures, liquid level, specific gravities, etc. P. Mo u f a n g

(B.P. 324,929, 1.11.28).—In a known system in which a je t of compressed air is more or less obstructed with con­

sequent variation of pressure in the air-supply pipe, the pressure variations acting through relays to efiect the required control, the obstructing valve is often affected by the pressure of the jet. In this invention the obstruc­

tion moves at right angles across the j e t ; it may, e.g., be mounted on the pointer of a pressure gauge, on the arm produced of a float valve, or on the stem of a hydrometer. B. M . Ve n a b l e s.

Vacuum m easurem ent. A.-G. Br o w n, Bo v e r i &

Co. (Austr.P. 109,131, 21.5.26.. Ger., 2.6.25).—The apparatus comprises a U-shaped, bifilar, bimetallic strip through which is passed a constant current. The temperature of the strip changes with the degree of vacuum, and the consequent variations in the shape of the strip are rendered visible by means of an indicator needle moving over an appropriate scale. A. R. Po w e l l.

Indicating therm om eter filled w ith two liquids.

St e i n l e & Ha r t u n g Ge s.m.b.H . ( G .P . 458,926,16.3.26).

—A thermometer of the type in which the expansion caused by heat operates an indicator by means of an elastic membrane is completely filled with two immisc­

ible liquids neither of which boils within the temperature range of the thermometer and one of which has a higher coefficient of expansion than the other.

A. R. Po w e l l.

V essel for conducting chem ical tests and m ea­

su rem en ts, e.g., titrations. J. Li n d n e r (G.P. 459,627, 27.11.26).—The vessel of any suitable shape is provided with a pocket-like, external, auxiliary vessel connected to the main vessel by an outlet above the surface of the liquid therein. The auxiliary vessel serves to retain a portion of the liquid to be titrated until the end-point has been reached with the main volume, and is thus applicable for titrations requiring'an outside indicator.

A. R. Po w e l l.

Evaporator and process of evaporation. P. B.

Sa d t l e r, Assr. to Sw e n s o n Ev a p o r a t o r Co. (U.S.P.

1.735.979—80,19.11.29. Appl., [a] 9.7.26, [b] 6.8.27).—

See B.P. 321,698 ; B., 1930, 87.

Fractional d istillation. R. B. Ch i l l a s, j u n.,

Assr. to Ba r r e t t Co. (Re-issue 17,595. 18.2.30, of U.S.P. 1,612,572, 28.12.26).—See B., 1927, 129.

Furnace w all construction. M. H . De t r i c k Co.

(B.P. 307,919, 26.2.29. U.S., 17.3.28).

Chem ical fire extin gu ish ers. T. II. Ba r t o n ( B .P .

325,046, 13.12.28).

A m m onia as lubricant (U.S.P. 1,739,957).—

See VII. Filtering etc. of liquids (B.P. 325,004).—

See X X in .


C om position of peat-form ing plants and varieties of peat. I. G . St a d n ik o v and A. Ba r y s c h e v a (Brenn- stoff-Chem., 1930, 1 1 , 21—23).—Methods previously used for the analysis of peat are criticised. The com­

position of samples of peat taken a t different depths of the Elektroperadatsche peat bog lias been compared with th a t of the peat-forming plants (Sphagnum parvifolium, Eriopliorwn vaginalum). The samples, were analysed by extracting successively with (a) benzene- alcohol mixture, (b) hot water, and (c) 1% sodium hydr­

oxide ; the last extract was subdivided into humic acids, which were precipitated by sulphuric acid, and acids soluble in ether and alcohol, respectively. The lignin content of the residue was determined by W illstatter’s method and the cellulose calculated by difference.

During the peat-forming process the sugars, pectins, and cellulose of the plant disappear; the lignin decreases in amount and shows also a progressive increase in its carbon content. At the same time insoluble salts of monocarboxylic and other more complex acids a p p e a r; these are regarded as inter­

mediate products in the formation of the humic acids

from lignin. A. B. Ma n n in g.

Form ation of fusain from a com paratively recent angiosperm . W. P . Ev a n s (New Zealand J.

Sci. Tech.. 1929, 1 1 , 262—269).—Samples of fusain, estimated to have been laid down a t least 10,000 years ago, were probably formed by direct heat action of a pumice shower on the original wood, and modified by prolonged bacterial action under anaerobic conditions subsequently. A series of photographs is provided.

E. Ho l m e s.

Coking pow er and sw ellin g of coal. I. H. A. J-

Pi e t e r s (Rec. trav. chim., 1930, 4 9 , [iv], 289—306).—A knowledge of the coking properties of a coal may be obtained by determining its volatile m atter, heating 1 g. of the coal a t 850° for 2 i lnin. and measuring the volume of the coke button produced, determining its Campredon caking index, measuring its softening point when heated a t the rate of 9°/min., determining its swelling power when heated (5°/min.) underpressure, or finding the tem perature a t which rapid evolution of gas begins and the rate a t which gas is evolved when 2 g. of coal are heated a t the rate of 4°/min. E x a m i n a t io n

of 28 samples of coking, non-coking, and gas coals by


B r itis h C h em ica l A b s tr a c ts — B .

Cl. I I . — Fu e l ; Ga s ; Ta r ; Mi n e r a l Oi l s.

the above methods shows that (i) a correlation may be made between the am ount of volatile m atter in the coal, its caking index, and the volume of the coke button, high volatile m atter corresponding with high caking index and a large coke-button volum e; (ii) for coals with a gas content of 18—25%, their coking and swelling pro­

perties are a function of their volatile m atter content, but with coals having a gas content above 30% and with certain blends of coal this relationship no longer holds good ; (iii) coking coals have lower softening points and commence to evolve gas a t lower temperatures than low-volatile non-coking coals; (iv) coking coals begin to swell considerably and to soften a t 360—420°.

When the plasticity diminishes the swelling decreases and the volume of the coal becomes constant, but at 650—825° a definite shrinkage occurs, whereas a non- caking coal never swells but gradually shrinks during the whole period of its destructive distillation : (v) gas coals give low swelling values when tested in an open crucible, and when coking takes place under pressure these coals show only a tem porary swelling and after­

wards shrink : (vi) Campredon’s method of evaluating the caking power of a coal gives uncertain results, and is too tedious ; it is therefore not recommended as a routine test. Theoretical reasons are advanced for these conclusions and their application to blending problems is discussed. C. B. Ma r s o n.

Relation betw een caking power and coking test of coal. I. T ests b y L e ssin g ’s apparatus. II.

Influence of w eathering. S. Ik i (J. Soc. Chem. Ind.

Japan, 1930, 33, 9—11b).—The gas and coke yields in the Lessing apparatus tend to increase with decrease of caking power. The ta r yield rises and then falls again. The production of ta r from the four coal con­

stituents decreases in the order y, ¡3, a, ulmin, whilst th at of gas increases. Yield of gas here refers to volume, which is in inverse ratio to the calorific value. Coals of various caking powers were exposed to temperatures from 100° to 250° for 10 hrs. and then tested. I t was found th a t the volume of gas yield tended to increase owing to replacement of hydrocarbons by carbon mon­

oxide. The tar yield decreased. Slight weathering of caking coal increased the swelling power. C. Irw in.

Complete gasification of coal : tests of the su it­

ability of coal for com plete gasification. B . Me z g e r

and T. Pa y e r (Gas- u. Wasserfach, 1 9 3 0 , 7 3 , 1— 8 ).—

The “ double-gas ” process for complete gasification provides a valuable adjunct to existing methods of gas production, mainly in respect of the rapidity with which the plant can be brought into operation and the ease with which the gas so produced may be blended with coal gas, producer gas, etc. to give a mixture of the desired calorific value. The mode of operation of the plant is described, and special reference made to diffi­

culties experienced ; these are mainly concerned with the properties of the coal used. A suitable coal should be of uniform size, free from fine material, non-swelling and non-caking, should give a high yield of gas and tar in proportion to the residual coke, and should yield its volatile constituents a t the lowest possible tempera­

ture, a gas of high calorific value, and a ta r capable of being readily cracked to a high-value gas. Methods

of examination of coal are described in detail with the aid of diagrams, and the results obtained from actual tests of various coals are tabulated. Assistance in evaluating a coal as to its suitability is given in recom­

mendations for the limiting values obtained by the various tests, with special reference to swelling and caking, which greatly affect the working of the “ double­

gas ” plant. D. G. Mu r d o c h.

D esulphurisation of gases either free from or containing am m onia b y the process of the Ges. f.

Kohlentechnik. W . Gl u u d, W . Ex e m p t, and F.

Br o d k o r b (Brennstoft'-Chem., 1930, 11, 23—27 ; cf. B .,

1927, 321 ; Ferbers, B ., 1929, 5).The plant a t the Zeche “ Viktoria,” Lünen, is described. I t has a daily throughput of 20,000 cub. m. of gas containing 10—11 g.

of hydrogen sulphide per cub. m. The daily con­

sumption of sodium carbonate is 144 kg., and of iron 23 kg. ; the daily yield of crude sulphur is 255 kg., containing 55% S, 9% Fe (as hydroxide and sulphide), and 36% of water and other impurities. The material extracted from the new wooden grids by the alkaline solution caused undue foaming, which adversely affected the activity of the iron hydroxide suspension and interfered with the separation of the sulphur; it was therefore removed by pre-extraction. The activity of the suspension was determined in the laboratory by the rapidity of coloration on the addition of hydrogen sulphide and the subsequent rate of re-oxidation with compressed air. Luxmasse or Duisberger-masse (0-2—

0-3% in 0-5—0-6% sodium carbonate solution) proved to be suitable materials for making up the suspension, the activity of which could be improved by the addition of a manganese suspension. The thiosulphate content of the suspension is preferably not allowed to rise above 5%. The expensive consumption of sodium carbonate can be avoided if the gas is desulphurised while still containing the ammonia. Objections to this procedure, e.g., the possible formation of a calcium sulphate sludge due to the increased concentration of ammonium sul­

phate in the liquor, or the re-addition of hydrogen sulphide to the purified gas from the wrash oil in the benzol scrubbers, are shown to be without basis.

A. B. Ma n n i n g.

Cracking of prim ary tar from a coal of Donetzki Basin under hydrogen pressure. V. N. Ip a t i e v,

A. D. Pe t r o v, and I . Z. Iv a n o v (J. Appl. Chem. Russia, 1929, 2 , 429—435).—The ¿racking at 380—420° in presence of alumina and ferric oxide a t 70 atm. initial hydrogen pressure gave a lower yield of low-boiling substances soluble in sulphuric acid and a higher yield of liigh-boiling fractions than in absence of hydrogen.

By alteration of the conditions of cracking the aromatic content of the light products can be controlled.

Ch e m i c a l Ab s t r a c t s.

Cracking of gaseou s saturated hydrocarbons.

W . J. Pi o t r o w s k i and J. Win k l e r (Przemyśl Chem., 1930, 1 4 , 49—64, 83—92).—Gaseous hydrocarbons possessing 2—5 carbon atoms undergo pyrolysis a t all concentrations to give high yields (70%) of unsatur­

ated hydrocarbons. All hydrocarbons tend on pro­

longed heating to undergo conversion into methane, carbon, and hydrogen, and for each concentration and


B r itis h C h em ica l A b s tr a c ts —B .

310 Cl. I I . — Fu e l ; Sa s ; Ta b ; Mi n e r a l Oi l s.

composition of gas submitted to pyrolysis there exist an optimum tem perature and duration of heating at which maximum yields of defines are obtained. These are 730° and 8 sec. for the propane-butane gas derived from gasoline, 740—765° and 10 sec. for Cross distillation gas containing methane, and 780° and 11 sec. for Borysław gasoline-free natural gas, possessing a high air and methane content. Carbon formed during pyrolysis cata­

lyses the further disintegration of the unsaturated hydro­

carbons formed, thus leading to enhanced soot forma­

tion. The process of pyrolysis consists below 730° in the formation of propylene from propane, and of propylene and butylene from butane. Between 730° and 800°

propane yields chiefly ethylene, whilst butane yields ethylene and ethane. Above 800° acetylenie and aromatic hydrocarbons appear, together with carbon, hydrogen, and methane ; the proportion of polynuclear aromatic hydrocarbons rises with temperature.

R . Tr u s z k o w s k i.

Effect of branched alkyl groups on anti-knock properties of the lead triethylbutyl compounds.

H. Gi l m a n, O. R . Sw e e n e y, and J. D. Ro b in s o n (Rec.

trav. chim., 1930, 49, [iv], 205—207).—The preparation of the four lead triethylbutyl compounds and their examination for anti-knock efficiency by the bouncing- pin method are described. All four compounds are of about equal effectiveness, viz., 85% as efficient as is lead tetraethyl on a molecular basis (cf. A., 1929, 1092,

1472). C. B. Ma r s o n.

Influence of the cold -resistivity of n eat’s-foot oils on the greasin ess of the compound oils pre­

pared therefrom . P. Cu y p e r s (Ghem.-Ztg., 1930, 54, 30—31).—The neat’s-foot oils less resistant to cold (of higher m.p.) have a lower linoleic acid content (which confers improved chemical stability) and a higher stearic acid content than the similar oils which are more resistant to cold, and it is shown th a t the use of only the most cold-resistant and expensive neat’s-foot oils for compounding with mineral oils is unnecessary; the cheaper type of oils, having a smaller cold-resistivity, are found to offer considerable advantages when so used, producing better lubrication properties and prolonged chemical stability in the compound oils.

S . K . Tw e e d y.

Centrifuges for drying [solids] and separating [liquids]. Ve n z k e(Brennstoff-Chem., 1930,11,27—28).

—Two types of centrifuge are described, suitable, respectively, for the continuous drying of small coal and the S e p a r a t io n of heavy and light oils, or of oils from

sludges. A. B. Ma n n in g.

Sulphite-cellulose w aste liquor. Sc h w a l b e.—

See V. Fertilisation and the coal industry. Sc h u l t e- Ov e r b e c k.—See XVI.

Pa t e n t s.

Coke ovens. P. E. Ve r p e a u x, and Un io n Ch em. Be l g e, So c. An o n. (B.P. 324,584, 12.4.29).—The fuel gas is supplied to the vertical flues of a horizontal coke oven through chambers immediately underneath the flues, while air, in amount insufficient for the complete combustion of the gas, enters at the bottom of the flue from regenerators situated below the ovens. In the walls between the individual regenerators are air-expan-

sion chambers, connected on one side with pipes supply­

ing air under pressure and on the other side with auxiliary flues which open a t different levels in the heating flues, and thus supply secondary air to complete the combus­

tion of the excess gas. A. B. Ma n n i n g.

Coke ovens. W. Dia m o n d (B.P. 324,195, 20.12.28).—

To facilitate the withdrawal of charges which adhere to the oven walls, liners are provided within the ovens.

These m ay be in the form of plates of wedge section (thin end downwards), and adapted to be raised by suitable hoisting gear, or they may consist of plates normally slightly inclined to the oven walls and adapted to be rocked back from the face of the charge.

A. B. Ma n n i n g.

R etorts for treating coal, peat, sh ale, etc. D. D.

Sh e l t o n (B.P. 324,348, 19.7.28).—A vertical retort comprises a central heating chamber down which pass- the hot combustion gases from a furnace, and on two sides of which are narrow carbonising chambers. The outer walls of the latter are movable so th a t the width of the carbonising chambers can be varied as desired.

The inner sides of the movable walls are provided with spaced louvres in between which are movable blades connected to an agitating mechanism. Means are pro­

vided for feeding the material continuously in a t the top of the carbonising chambers and discharging the product through regulatable apertures on to hinged floors the free ends of which engage with the radial blades of internally cooled rotating drums in such a manner as to shake the carbonised material over the outer surface of the cooling drums into a hopper. The volatile products of distillation pass through the louvred wall to condensing chambers adjacent thereto.

A. B. Ma n n in g.

Apparatus for recovery of valuable constituents in coal, peat, lignite, etc. C. C. La r s e n (B.P. 307,021, 25.2.29. Denm., 1.3.28).—The pulverised fuel is dis­

tilled in an internally heated retort, whence it is con­

veyed directly to the furnace of a steam-raising plant.

After recovery of the ta r etc. in a suitable condensing system, a part of the distillation gases is passed through a pipe coil within the furnace and recirculated through the retort, thus forming the heating medium for the

distillation. A. B. Ma n n in g.

Apparatus for distillation of solid carbonaceous m aterials. II. Ni e l s e n and B. La i n g (B.P. 324,212, 30.7.28).—An inclined rotary retort is divided longi­

tudinally into a number of separate compartments.

Helically twisted blades are provided a t the ends of the retort for feeding the material from the charging chute into the compartments and for conveying the carbonised material into the discharge chute. Stationary gas-inlet and -outlet pipes are provided a t the ends of the retort through which a gaseous heating medium may be brought into direct contact with the material.

A. B. Ma n n in g.

Apparatus for separation from solid residues of o ils o b ta in e d in the destructive h y d r o g e n a tio n of varieties of coal, tars, m ineral o ils, etc. under p ressure. J . Y. Jo h n s o n. From I. G. Farbenin».

A.-G. (B.P. 323,791, 11.9.28. Addn. to B.P. 312,657;

B., 1929, 633).—The residues are mixed with solvents


B r itis h C h em ica l A b s tr a c t* —B.

Cl. I I .— Fo i l ; Ga s ; Ta r ; Mi n e r a l Oi l s. 3 1 1

and the mixture is filtered iu an apparatus to and from which the solvent, the mixture, the extracted products, and the extracted residues are continuously supplied and removed. The solvents used are preferably oils of boiling range 150—300°, derived from the destructive hydrogenation process itself. The residues from the filter may be subjected to a subsequent low-temperature carbonisation. A. B. Ma n n i n g.

Fractional dry d istillation of organic m aterials.

J. Mü l l e r (G.P. 457,500, 28.1.25).—The material, e.g., coal, peat, wood, is fed in small quantities into the apparatus wherein it is heated a t once to the distilla­

tion temperature. The distillation gases are separated into their different fractions by being passed through filters which are heated by the gases themselves in successive zones in such a manner th a t the temperature of the filter a t the gas outlet lies directly above the initial tem perature of condensation of the succeeding stage. The filters are connected to a series of openings serving as gas outlets and leading to the corresponding condensers. One or more filters may be arranged below the distillation chamber and connected directly thereto.

A. B. Ma n n i n g.

D ry distillation of brow n coal. A. G. Pu l t (F.P.

634,300, 12.5.27. It., 25.5.26).—The plant consists of a furnace containing one or more retorts the heads of which are especially long and so arranged th a t compounds of the aliphatic series of which brown-coal ta r consists are converted therein into aromatic compounds.

A. B. Ma n n i n g.

G asification and carbonisation of earthy m o ist fuels, e. g. , raw brown coal. C. A rnem ann (G.P.

458,879, 12.2.22).—The coarser fuel is separated from the dust, and is fed directly into the generator. The dust is burnt in a combustion chamber in the lower part of the generator, and the hot combustion gases are used for drying, carbonising, and gasifying the coarser fuel in the generator shaft. A. B. Ma n n i n g.

Manufacture of w ater-soluble products from lignite and sim ila r fo ssil m aterials. I . G. Fa r b e n i n d.

A.-G. (B.P. 323,781, 10.10.28. Addn. to B.P. 284,670 ; B., 1929, 505).—Lignite degradation products, soluble in dilute acid, are treated with chlorine until the medium becomes acid, if not already so, and the chlorine tre a t­

ment is continued with the gradual addition of alkali in such manner th a t the reaction medium remains just acid to litmus, and only becomes more strongly acid towards the end of the process. II. S . Ga r l i c k.

Production of low -tem perature coke. C. B. Wa t s o n

and R. H. Ca r r (B.P. 323,829, 20.10.28).—Bituminous coal is charged under pressure, e.g., by means of a reciprocating ram, into the bottom of a cylindrical chamber, wherein it travels upwards countercurrent to a gaseous heating medium, e.g., superheated steam. A central vertical shaft carries a conveyor blade which controls the upward motion of the coal. The coke is withdrawn in a compact form, being propelled through a tangential conduit near the top of the chamber by means of a spiral conveyor. A number of arms having their outer ends connected by means of a ring are a t­

tached to the upper part of the shaft. The arms and the ring carry depending fingers which by their rotation

break up the surface of the fuel so as to render it readily pervious to the heating medium. The volatile products of distillation are withdrawn through a circular, per­

forated manifold a t the bottom of the chamber, and pass to a suitable condensing system. A. B . Ma n n i n g.

Preparation or revivification of active carbon.

Me t a l l b a n k u. Me t a l l u r g. Ge s. A .-G ., and II. v o n

Ha l b e r n ( G .P . 459,347, 14.8.25).—The carbon is sub­

jected to alternate short reduction and oxidation trea t­

ments in a divided electrolytic cell, in which the electro­

lyte contains a substance which in the anode compart­

ment becomes oxidised to an active oxidising agent and in the cathode compartment is reduced to a powerful reducing agent. A . R . Po w e l l.

Com posite fuel. J. A. Gr e e n e, and Bin d p h a s t Pr o d u c t s, Lt d. ( B .P . 324,081, 18.10.28).—A bitum­

inous or other combustible substance, e.g., small coal, is mixed with a relatively small quantity of calcined dolomite, and with sufficient of an aqueous solution of chlorine or hydrochloric acid to form a plastic coherent mass, which is then briquetted. Alum may be added to the mixture to make it dry more rapidly, and clay to produce a slower-burning fuel. A. B . Ma n n i n g.

D eterm ination of m oisture in coal and sim ilar su bstances. H . He i n i c k e (G.P. 458,927, 29.1.26).—

The coal is packed round an electrically-heated wire within a suitable containing vessel; the moisture content of the coal is then determined from the change in the resistance of the wire. A. B. M a n n i n g .

G as-m aking retorts. C. L. Sin c l a i r and C. M . Cr o f t (B.P. 323,909, 31.12.28).—In retorts having pro­

jector-type coal-charging machines, a shield is provided within each retort which normally fits against the lid, bu t which can be moved forward during the charging operation, e.g., by means of a rod passing through a hole in the lid and screwing into a spigot on the shield, so as to act as a barrier to prevent coal reaching the mouthpiece, while permitting gas to pass freely to the ascension pipe. A. B. Ma n n i n g.

A pparatus for production of gas from wood and d ry purification thereof. E . M . Ra u j o u a n

(F.P. 633,237, 23.4.27).—The plant comprises a genera­

tor with a container for the wood situated above the hearth, a cooling arrangement attached thereto and consisting of two horizontal collecting chambers con­

nected by four narrow pipes, a purifier with a lower chamber for the separation of the solid gas impurities, a condenser, a liquid seal, and a valve.

A. B . Ma n n i n g.

G eneration of hydrogen. R . Ba t t ig (B.P. 294,113, 14.7.28. Ger., 16.7.27).—The methane fraction obtained by the liquefaction of coke-oven gas is converted by inter­

action with steam and/or oxygen into carbon dioxide and hydrogen. The carbon dioxide is removed by washing the gas mixture with water under pressure, and the hydrogen is purified by fractional liquefaction, e.g., by the use of liquid nitrogen. The gas may finally be washed with liquid nitrogen in such a manner as to give a mixture of hydrogen and nitrogen suitable for the synthetic manufacture of ammonia.

A. B . Ma n n i n g.


B r itis h C h em ica l A b s tr a c ts — B .

312 Cl. II.— Fc t e l; Ga s; Ta k ; M u n t n A L Oi l s.

H ydrogen and hydrogen-nitrogen m ixtures.

No r s k Hy d r o- El e k t r i s k Kv a e l s t o f- A ./S . ( F . P .

627,665, 18.1.27. Norw., 13.2. and 9.12.26).—Steam, alone or mixed with air, is passed through carbon raised electrically to incandescence, and hydrogen, alone or mixed with nitrogen, respectively, is ob­

tained from the water-gas produced by removal of the carbon dioxide etc. Alternatively, the water-gas is employed to reduce ferric oxide and, after removal of the excess steam and carbon dioxide, is repassed through the incandescent carbon together with the requisite quantity of steam ; the reduced iron is used to decompose further quantities of steam, the first, impure hydrogen thus obtained being added to the circulating reducing gas and the pure hydrogen subse­

quently obtained being used for the preparation of

ammonia. S . K. Tw e e d y.

Production of a m ixtu re of hydrogen and carbon m onoxide b y decom position of hydrocarbon gases or vapours in th e presence of steam . D. Ty r e r,

and Im p e r i a l Ch e m. In d u s t r i e s, Lt d. (B.P. 323,864-, 16.11.28).—Coke-oven gases etc. are mixed with a limited supply of steam, e.g., 5—16% by vol. for a gas containing 30% CH4, and passed through a bed of preheated refractory material. The heat of the gases produced is used to preheat air, and the heat required to bring about interaction of the steam and the hydro­

carbons in the gases is obtained by the combustion of the deposited carbon in the preheated air, each reaction period being followed by a reheating period.

A . B . Ma n n i n g.

M anufacture and utilisation of w ater-gas. Fa b r. Na t. d e P rod. Ch i m. e t d’Ex p l o s i f s So c. An o n. (B.P, 317,460, 19.10.28. Belg., 17.8.28).—The residue from the carbonisation of a mixture of coal with about 15%

of iron oxide, obtained as described in B.P. 296,443 (B., 1930, 7), is used in a water-gas generator. The gas thus produced has a higher calorific value than ordinary water-gas and is particularly suitable for the synthesis of light petrols, methyl alcohol, etc. A . B. Ma n n i n g,

Separation of hydrogen sulphide and hydrogen cyanide from gases. Soc. An o n. Ho l l a n d o-Be l g e p o u r l a Fa b r. d u Co k e (B.P. 314,860, 11.6.29. Ger., 3.7.28. C f. B.P. 195,061; B., 1923, 929 a).—The gases arc washed with an alkali carbonate solution, from which the hydrogen sulphide and hydrogen cyanide are sub­

sequently expelled by means of carbon dioxide. The gases from the expelling apparatus are passed through a purifying box in which the hydrogen sulphide is separated in any manner which does not fix the carbon dioxide, e.g., by hydrated iron oxide, and arc again used for expelling a further amount of hydrogen sulphide from the wash liquor. Preferably only tbe upper layers of the wash liquor are treated with these re­

circulated gases, the lower layers being freed from hydrogen sulphide by means of carbon dioxide obtained by heating the bicarbonate liquor. A . B . Ma n n i n g.

Gas purification (rem oval of benzol). Soc. An o n, d e s En g r a i s e t No i r An i m a l (F.P. 636,162, 12.10.26).

—The benzol is absorbed in activated carbon. Only very highly active carbon is used and the plant is constructed to work automatically. A . B. Ma n n i n g.

Shaft furnace for production of low-tem perature tar. Al l g e m. Ve r g a s u n g s-Ge s.m.b.H . (G.P. 459,307, 5.6.21. A d d n . t o G.P. 435,210; B., 1927, 291).—T h e d e s i g n o f t h e s h a f t f u r n a c e d e s c r i b e d i n t h e p r i o r p a t e n t is m o d if ie d b y r e d u c i n g t h e a r e a o f c r o s s - s e c ti o n o f t h e u p p e r p a r t t o a b o u t o n e t h i r d t h a t o f t h e lo w e r.

A. B. Ma n n i n g.

E xtraction of oil from solid fu els, sh ales, tor- banites, etc. J. L. St r e v e n s (B.P. 323,773, 6.10.28).—

Carbonaceous materials are ground in oil, an oil-soluble colloid is added, and the resultant m ixture is pumped a t 300—350° and 40 atm. into tubular digesters where the tem perature is raised to about 400°. The digested mixture is then pumped through pressure-cracking con­

duits at normal cracking tem peratures into soaking tubes, and the cracked mixture released through pres­

sure-reducing valves into an evaporator from which the lighter volatile fractions are removed. The residual mixture is filtered and the ho t oil returned to the system to be mixed with solid fuel again ; the solid m atter left on the filters may be used as a dustless powdered fuel or briquetted. Catalysts may be added to the mixture a t any suitable stage in order to modify the character of the reactions. H. S . Ga r l i c k.

H eating of [petroleum ] oil. J. Pr i m r o s e, Assr. to

Fo s t e r Wh e e l e r Co r p. (U.S.P. 1,738,263, 3.12.29.

Appl., 2.7.23).—In the operation of an oil still, fuel is burnt in an enclosed space and air is supplied in sub­

stantial excess of the amount required for the combustion of the fuel, to lower the temperature and increase the volume of the combustion gases. H eat is absorbed by subjecting circulating oil to direct radiation, and by convexion from the products of combustion and excess air as these pass into a second enclosed space, where the remaining heat is utilised in heating further circulating oil and preheating substantially all the excess air supplied to the first enclosed space. H. S. Ga r l ic k.

Preparation of aqueous d ispersions of petroleum products. N. V. De Ba t a a f s c h e Pe t r o l e u m Ma a t- s c h a p p i j ( B .P . 302,346, 13.11.28. Holl., 15.12.27).—

Natural emulsifying agents such as uaphthenic acids and acid resins are contained in many mineral oils.

When the residues from these oils are to be emulsified the emulsifying agent is retained in the oil by the addi­

tion of sufficient alkali before distillation. The residue is then dispersed directly in water or acidified to set free the organic acids and then emulsified in dilute soda solution, preferably by the aid of a colloid mill.

The naphthenic acids recovered from some distillates may be used as emulsifying agents. T. A. Sm i t h.

Continuous treatm ent of hydrocarbons with liquid sulphur dioxide. A l l g e m . Ges. f . C h e m . I n d . m .b .H . (G.P. 457,580, 16.11.26).—The refined product as well as the extract is subjected to a continuous process of evaporation in stages under successively different

pressures. A . B. M a n n i n g .

T reatm ent of heavier hydrocarbons. C. A.

Je n s e n. From Je n k i n s Pe t r o l e u m Pr o c e s s Co.

( B .P . 324,112, 18.10.28).—In a cracking plant in

which oil and contact material are circulated through heating tubes, cracked distillate and residue are con-




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