British Chemical Abstracts. B.-Applied Chemistry. February 1

(1)

BRITISH CHEMICAL ABSTRACTS

B.—A PP L IE D CHEMISTRY

FEBRUARY 1, 1929.

I .-G E N E R A L ; PLA N T; MACHINERY.

Evaporation at low tem peratures [in the labora

tory].—E. Ja n t z e n and H . Sc iim a l f u s s (Cliem. Fabr., 1928, 701—703).—A copper batli with outer sheet-iron jacket is heated by a small burner, and the liquid con

tents are stirred by a high-speed screw running within a small vertical pipe inside the bath. The distilling flask of glass or Krupp V2A steel is connected by a wide glass tube to a copper condenser with seven longitudinal cooling-water tubes. The condensate passes to WoulS’s bottles, connected to several water pumps and to a manometer. This apparatus will distil 7 litres of water per hr. a t a temperature 6° above th a t of the cooling water. By the use of ice in place of cooling water liquids can be distilled a t temperatures down to —19°, the bath being filled with a freezing mixture.

C. Ir w in.

V iscosim eters for oils. Bl e y b e r g, also Ho l d e.

Fractionating colum ns. Ko s t r in.—See II. Monel m etal as tower packing. We i s s e n b e r g e rand Pia t t t.

—See X. X -R ay equipm ent. Cl a r k.—See XI.

H igh-vacuum grease. He in r ic h and Pe t z o l d.—

See X II.

Pa t e n t s.

Furnaces. Ca r b o r u n d u m Co., Lt d., Assees. of C. E . Ha w k e (B.P. 282,720, 9.11.27. U.S., 27.12.26).—A

“ radiating combustion chamber ” or carborundum tube, having a burner at one end, within which combus

tion takes place in a somewhat confined manner, is cooled on the side which would otherwise become hottest owing to its being unable to effect useful radiation, by means of the air for combustion on its way to the burner.

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

Furnaces. Me t r o p o l it a n-Vic k e r s El e c t r ic a l Co.,

Lt d. From We s t in g h o u s e El e c t r ic& Ma n u f. Co. (B.P.

300,862, 22.3.28).—In a furnace in which a series of hearths move in a cycle, and at one place are tilted, the travelling motion and tilting motion control each other reciprocally and are interlocked so that only one motion can take place a t a time. Separate electric motors may be used with a common controlling switch which can only be on for one motion and off for the other.

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

Furnace. G. F. Be a c h, Assr. to F. J. Ry a n & Co.

(U.S.P. 1,690,710, 6.11.28. Appl., 4.6.26).—A furnace, e.g., a tunnel kiln, is provided with a heat-distributing chamber within the furnace walls, which is fitted with upper and lower ports leading into the heating chamber, the upper one being adjustable. B . M. Ve n a b l e s.

Regenerative furnace. H . Ba n g e r t and G. Hu h n

(U.S.P. 1,691,913, 20.11.28. Appl., 30.12.27. Ger., 20.1.23).—The furnace has two gas flues arranged to

communicate alternatively with the stack or with a source of gas supply and connected with separate regenerator chambers, a burner flue communicating with the furnace, and a flue for the supply of air. All these flues meet at a common mixing point where the gas mixture is ignited, and all but the last are so arranged with respect to one another that the products of com

bustion are divided into two portions, one of which passes along the burner flue and the other to the flue which is in communication for the time being with the

stack. A. R . Po w e l l.

Furnace for m alt or other drying kilns or for open firegrates or basket fires. J. Sa u n d e r s (B.P.

300,322, 20.8.27).—The air for combustion enters front

ally at the sides of the firegrate and passes under side cheeks and a hollow fire bridge, then under and through the firegrate. Constructional forms for domestic fires, drying kilns, boiler furnaces, etc. are shown.

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

Heat exchanger. A. P. Br o c k l e b a n k, Assr. to

Fo ster Wh e e l e r Co r p. (U.S.P. 1,689,910, 30.10.28.

Appl., 5.11.27).—For a heat exchanger of the nest-of- tubes type having a longitudinal baffle, a fluid-tight packing between the edges of the baffle and the shell is described. B . M. Ve n a b l e s.

Heat exchanger. C. B. Gr a d y (U.S.P. 1,690,108, 6.11.28. Appl., 30.10.24).—A hot outer fluid heats a liquid, and the vapour therefrom heats the inner fluid which is passed through the upper portions of a series of containers for the heat-transmitting liquid.

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

Heat-exchange apparatus. G. T. Jacocks, Assr.

to Wiu t l o c k Co il Pip e Co. (U.S.P. 1,691,012, 6.11.28.

Appl., 10.12.26).—A method of construction of a heat exchanger comprising a nest of tubes with baffles so that the outer fluid flows in a zigzag course transverse to the tubes, is described. The outer shell is contracted tightly upon the flanges of the tube plates and the baffles, which are circular and of the same diameter.

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

H eat-exchanging coil. E . I. He in s o h n, Assr. to

Glascote Co. (U.S.P. 1,689,435, 30.10.28. Appl,

26.1.25).—A glass-coated pipe coil has its convolutions kept apart by spacers which are also glass-coated and integrally united with the tube. B . M. Ve n a b l e s.

Rotary heat exchanger. F. S. Br o a d h u r st (U.S.P.

1,689,189, 30.10.28. Appl., 30.3.25).—A number of hollow discs are mounted on a rotating hub with inlet and outlet passages and ports corresponding to openings formed in the walls of the discs, the whole forming a tortuous passage for the inner fluid. The outer fluid flows over the outside of the discs and hub between

(2)

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

78 Cl. I . —Gen era l ; Plant ; Macjhinebt.

them and an outer fixed shell, the passage being made tortuous by annular baffles extending inwards from the shell and interleaved with the hollow discs.

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

Apparatus for heat-treating articles. W . L . Sc h u l e n b e r g (U .S .P . 1,690,555, 6.11.28. Appl., 15.2.27).

—The seal between a movable hearth and the fixed portion of the furnace is formed by intercalating beams, one with a trough-like pocket, the other with a flange dipping into the trough, and a seal of loose, powdered, heat-insulating material is placed therein.

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

Apparatus for heat application. W . A. Da r r a h

(U.S.P. 1,689,379, 30.10.28. A ppl, 29.12.24).—A main body of gases of combustion is kept in circulation by a blower passing over the object to be heated. A smaller portion of fresh hot gases is taken from a combustion device and added to the main stream, and a corre

sponding quantity of used gases is exhausted through a relief valve. The fuel supply to the combustion device is regulated by a thermostat in the circulating gases.

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

Supplying heat in high-pressure reactions.

I. G. Fa r b e n i n d. A.-G. (B.P. 275,248, 28.7.27. Ger., 28.7.26).—In processes such as the hydrogenation of oil or coal or the conversion of alcohols such as methyl or ethyl alcohol into higher alcohols by the action of carbon monoxide or water-gas, the heat is supplied wholly or partially by a preheated non-metallic gas which is not decomposed at the temperature of the reaction, bub which is not necessarily inert. The gas is brought into direct contact with the materials and is preferably used in large amounts to avoid local overheating. The preheating is effected by means separate from the reaction vessel, and the preheater is protected from access of reaction products. The reacting materials may themselves be preheated, but not up to the temperature of the reaction. B. M. Ve n a b l e s.

P rocess and apparatus for transferring heat.

R. C. Ne w h o u s e (U.S.P. 1,689,927, 30.10.28. Appl., 14.12.23).—A fluid is heated by gases of combustion in such a way that, although the incoming fluid is below the dew point of the gases, no condensation is caused.

The incoming cold liquid flows through the inner of pairs of concentric tubes, and the emerging hot liquid returns through the annular spaces between the inner and outer tubes. The outer tubes are heated by the gases, and one a t least of a pair of tubes is tapered so th at during at least one pass the liquid flows with decreasing velocity. B. M. Ve n a b l e s.

H eat-responsive m aterial. P. B. Co c h r a n, Assr. to

We s t in g h o u s e El e c t ric & Ma n u f. Co. (U.S.P. 1,693,369, 27.11.28. Appl., 21.4.27).—The material consists of a waterproof vehicle, and a composition which includes about 30 pts. of cuprous iodide and 70 pts. of mercury iodide. H. Ro y a l- Da w s o n.

Wet grinding of m aterials in tube or ball m ills.

F. Kr o t p Gr u s o n w e r k A .-G . (B.P. 292,941, 18.4.28.

Ger., 27.6.27).—In the type of grinding mill having a discharge chamber between the grinding chamber and the hollow outlet trunnion, the last-mentioned is pro

vided with a double conical deflector which can be

adjusted axially to return more or less of the ground material back to the grinding chamber.

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

Grinding m ill. C. E . Ne e d h a m, Assr. to Be t h l e h e m Fo u n d r y & Ma c h in e Co. (U.S.P. 1,690,125, 6.11.28.

Appl., 3.2.25).—A grinding mill of the centrifugal roll type is constructed in such a way th at it can be assembled either right or left hand from identical parts.

Pulverising m ill. L . C. Bo n n o t, Assr. to Bon n o t Co . (U.S.P. 1,690,712, 6.11.28. Appl., 23.5.25).—A rotating drum with balls or other grinding media is fed with material through one end of the drum at the axis.

At the other end is a fixed, axial, air-exhaust pipe, cranked upwards within the mill and terminating (com

mencing) as a perforated dust collector extending sub

stantially right across the mill, through which the dust is withdrawn by suction, the air necessary being admitted to the mill through inlets near the axis a t each end of the mill. The middle and lower interior parts of the mill are thus left without obstruction to the grinding material. B . M . Ve n a b l e s.

Pulveriser. T. C. Al f r e d (U.S.P. 1,691,951, 20.11.28. Appl., 12.12.25).—In a disintegrator the grizzly bars are held in recesses in the side walls of the machine and are put into compression by a wedge

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

M ills. F . E . Ma r c y (U.S.P. 1,690,493—6, 6.11.28.

Appl., [a] 7.6.27, [b, c] 28.12.27, [d] 21.3.28).—The patents relate to discharge grates for a Marcy mill.

In (a) the grate is provided with deflectors which move the balls and ore away from the grate a t intervals, thus freeing it from oversize material. In (b) the grates are inclined to the vertical and provided with members to free them from oversize. In (c) the discharge circle is made up of rectangular grates alternating with trian

gular, imperforate deflectors which are triangular in cross-section also. In (d) both the grates and imper

forate sections are sector-shaped and grouped round a many-sided pyramid which keeps the grates free of

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

M ill. C. G. Wil l a r d, Assr. to Min e & Sm e l t e r Su p p l y Co. (U.S.P. 1,690,447, 6.11.28. Appl., 10.6.27).—

In a mill [of the Marcy type] (cf. preceding abstract) deflectors are placed near to both the feed and discharge ends of the drum, to effect lateral displacement of the charge without reducing the length of the grinding

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

Crusher. H . H . Ru m p e l, A ssr. to S m ith En g i n e e r in g Wo r k s (U .S .P . 1,691,553, 13.11.28. A ppl., 20.12.26).— A cone cru sh er is described in w hich th e ax is of th e conical h e a d m oves in a circle a n d is alw ays parallel to th e axis of th e m achine.

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

Crusher. J. A. Do r m e r and J. G. Ma l o n e (U.S.P.

1,692,161, 20.11.28. Appl., 25.6.26).—Between the gyratory crushing head and the fixed part of the crusher are spaced rings which are moved to a certain extent by the movement of the head and multiply the number of crushing zones. B. M . Ve n a b l e s.

Rotary separators. Pn e u m a t ic Co n v e y a n c e &

Ex t r a c t io n, Lt d., and W. A. Sm it h (B.P. 300,364,

(3)

Ol. I . — Ge n e r a l ; Pl a n t ; Ma c h in e r y. B r i t is h C h e m ic a l A b s t r a c t s — B ,

7 9

3.10.27. Addn. to B.P. 278,900; B., 1928, 3).—The secondary part of the separator (for fine dust) consists of a fan in front of an outlet comprising one or more perforated discs or cones; the fan rotates in such a direction th a t it produces a pressure against the flow of air or gas. B. M. Ve n a b l e s.

Centrifugal drying m achines. A. K . Ciio a d.

From Co w l e s En g in e e r in g Co r p. (B.P. 300,874,12.4.28).

—A centrifuge is rendered safe against the dangers of uneven loading by providing a heavy weight fixed on the axis within the basket, and by supporting the whole of the rotating part on a flexible diaphragm in such a manner th a t severe distortion of the diaphragm will apply a brake by causing suitably lined rotating parts to rub against stationary parts. B. M. Ve n a b l e s.

Rotary drying apparatus. J. B. Ve r n a y (B.P.

294,953, 30.12.27. F r„ 2.8.27. Addn. to B.P. 262,464 ; B., 1927, 719. Cf. B.P. 282,432; B., 1928, 430).—

The central driving shaft is omitted and the apparatus supported on rollers and driven by gearing. In place of the shaft is a heated, fixed, central cylinder, through, then over, which the material is pushed. Means are described for preventing clogging in the feed hopper and for control of inlet and outlet of material.

W ashing and drying m achines. Sie m e n s- Sc h u c k e r t w e r k eA.-G.,and W . We i n e r s (B.P. 300,048, 24.1.28).—The apparatus comprises a basket mounted on a spindle which when vertical rotates a t centrifugal speed, and when inclined a t an angle less than 90°

to the vertical rotates a t a much slower speed partly in the washing liquid. B. M. Ve n a b l e s.

Apparatus for the [dry] separation of solid substances of different sp. gr. J. Y. Jo h n s o n.

From I. G. Fa r b e n i n d. A.-G. (B.P. 299,936, 20.8.27).;—

The powdered material, which has already been screened into portions of uniform particle size, is fed through a side inlet to a vertical receptacle, where it is kept just in suspension by a current of air coming up through a travelling perforated belt or screen which forms the bottom of the shaft, and draws off the heavier material, while the lighter material is caused to overflow through a side outlet opposite to and higher than the inlet.

Centrifugal clarifying separator. Na t. Acme Co.,

Assees. of D. S. Pa t e r s o n and G. B. Pe t s c h e (B.P.

294,524, 9.5.28. U.S., 25.7.27).—The bowl comprises a number of annular compartments ; in the outermost one the muddy portion flows once the full axial length of the m achine; the partly clarified liquid, after traversing nearly the full length of the outer compart

ment, flows inwards to the second compartment, where it flows axially back again, spreading over the exterior of a filter cylinder and passing inwards through it.

Any mud collected on the filter is flung off.

Centrifugal extractor. C. A. Ke l s e y, Assr. to

Ge n. El e c t r ic Co. (U.S.P. 1,689,490, 30.10.28. Appl., 10.12.27).—A centrifugal extractor having a perforated basket is provided with a continuous feed and discharge device comprising a cylindrical member within and rotating with the basket, but capable of vertical recipro

cation relative to the basket. In the annular space between the cylinder and the basket are a number of flaps hinged to the cylinder and pressed outwards against the basket on the down stroke, but inclining away from it on the up stroke. There are several “ storeys ” of the flaps, and the feed is through the wall of the inner cylinder between two of the upper storeys, and the dis

charge for separated solid material is through large apertures in the outer basket below the lowest story of the scraping flaps, the liquor being discharged through the wall of the basket before the solid m atter is pushed so far down. B. M. Ve n a b l e s.

Centrifugal separators. Ak t ie b o l a g e t Se p a r a t o r

(B.P. 292,127, 12.6.28. Swed., 14.6.27).—Means for discharging the heavier liquid are described.

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

Separation apparatus and process. A. R . S ilv e r s i o n, Assr. to Cok e Rec l a m a t io n Co r p. (U.S.P. 1,689,536, 30.10.28. Appl., 15.11.24).—Liquid is caused to flow in a substantially horizontal direction between guide vanes which divide it into sections, the vanes being provided with adjustable flaps at the ends to cause the sectional streams of liquid to turn more or less into the vertical direction. The material is fed adjacent to the ends of the vanes and the heavier particles are collected and withdrawn by a transverse conveyor or elevator and the lighter particles by a longitudinal one.

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

Regulating the [consistency of pulps by the]

concentration of liquids. Ze l l st o f-f a b r. Wa l d h o f,

and R . Ha a s (B.P. 280,876, 21.10.27. Ger., 20.11.26).—

A paddle is rotated in the pulp by means of an electrical motor in which the current will vary if the viscosity varies, and the change of current may be made to regulate the flow of a diluting liquor. Another method is to have a constant-speed shaft driving the paddle shaft in the reverse direction through a chain of 3 bevel wheels ; the axis of the middle wheels (duplicated for convenience) can turn about the axis of the other shafts and is spring- controlled so as to deflect more or less according to the

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

Deposition of [tapering] cakes of solid m atter from fluids in which the solids are suspended.

Fil t r a t io n En g i n e e r s, In c., Assees. of F . W . Young

(B.P. 280,170, 9.8.27. U.S., 4.11.26).—Filter cakes are made in non-uniform thickness by obstructing the flow of filtrate in the drainage member behind the filter medium a t those places where the cakes are required to be thinner. One application is the manufacture of tapering shingles from asbestos cement slurry.

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

Filter. C. St. C. Bu r n s, Assr. to F. Ka y (U.S.P.

1.691.867.13.11.28. Appl., 23.1.26. Renewal, 28.9.28).

—The pulp is admitted to a pressure-filtering chamber through the walls of which the filtrate escapes, and from the walls the cake is scraped and drops into a worm- conveyor which presses it through a discharge valve.

Both sides of the valve are subject to chamber pressure, one side through the pulp in the conveyor, the other through a direct pipe ; the latter pressure tends to close the valve, which action is supplemented by a spring.

(4)

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

Filters for liquids. A. Grinning (B.P. 300,600, 16.8.27).—The filter comprises a pile of spaced discs, with an axial inlet and peripheral outlet or vice versa.

On the face of each disc is formed a zig-zag ridge extend

ing from the central opening to near the periphery, and the narrow space between the ridge and the next disc is the filtering passage. B. M. Ve n a b l e s.

Detection of suspended m atter in fluids and operation of m eans for indicating its presence.

W. Kid d e & Co., In c., Assees. of W. H. Fr e y g a n g (B.P.

272,914, 14.6.27. U.S., 17.6.26).—The particles of suspended m atter reflect light into a photo-electric cell which is otherwise not illuminated. B. M. Ve n a b l e s.

M ixing of liquids. F. E. Sm it h, A. P. H. De s- bo r o u g h, W. T . Th o m so n, H. F. Re y n o l d s, and E. W.

Bl a ir (B.P. 299,942, 26.8.27).—One of the liquids is injected tangentially into the wider portion of a cylin

drical shell having two different diameters, and forms a film which eventually issues a t the narrow end as a cylindrical sheet. The other liquid is sprayed by any convenient means within the cylindrical film, i.e., either within the narrow portion of the shell or a t the outlet. In the case of viscous liquids the shell may be rotated. B . M. Ve n a b l e s.

Apparatus for m ixin g liquids. I I . J. Lloy d

(B.P. 300,341, 7.9.27).—The apparatus is suitable for adding a small quantity of one liquid to another liquid flowing under pressure. The small quantity of liquid is contained in a closed vessel to the top and bottom of which there lead two passages from a Venturi tube in the main flow of liquid—one from a mouth, the other, which is also the outlet for the liquid being added, from the throat of the Venturi. The flow of the small quantity of liquid is controlled by needle valves.

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

Fractionating tower. Bubble still trays for fractionating tow ers. Po w e r Sp e c ia l t y Co. (B.P.

270,720 and 299,479, 3.5.27. U.S., 5.5.26).—The trays are constructed to give uniform distribution of liquid even though of a large diameter, and in the tower provision is made for drawing off all or part of the liquid falling from any tray. Reboiling may be effected in different sections, and entrainment is minimised.

Apparatus for filtering and bottling fluids under pressure. G. St r if f l e r (U.S.P. 1,692,393, 20.11.28.

Appl., 20.1.28).—A cylindrical shell is provided with, in order downwards, an air-tight detachable lid, a filter diaphragm, a false bottom, a real bottom. Compressed air can be supplied to the highest and lowest compart

ments, and there is a communication from above to below the false bottom. B. M. Ve n a b l e s.

Centrifugal disintegrator for liquids. W. S.

Bo w e n (U.S.P. 1,692,617, 20.11.28. Appl., 19.7.28).—

A rotating disc has a collar-like liquid container on its top surface. Openings are formed in the collar just above the disc and in the disc beyond the collar.

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

Apparatus for filtering gases. Ge n. Ai r Fil t e r s Co r p. (B.P. 288,992, 8.11.27. U.S., 18.4.27).—In the type of apparatus where the dust is caught in a viscous film spread upon baffle plates, the retention of liquid

up the baffle plates is improved by the provision of slits and liquid spreading devices. One suitable form of baffle is a sheet of expanded metal slit but not stretched.

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

Apparatus for cleansing and cooling gases. 0.

I Iu b m a n n, Assr. to Me t a l l b a n k & Me t a l l u r g is c h e

Ges. A.-G. (U.S.P. 1,690,635, 6.11.28. Appl., 8.11.26.

Ger., 8.8.25).—The gases and a washing liquid are caused to pass simultaneously through a number of converging- divergiug narrow passageways formed in the wall of a cylinder rotating within a casing. B. M . Ve n a b l e s.

Air and gas cleaner. C. S. Ha n s a r d and A. E . Ne t z e l (U;S.P. 1,691,971, 20.11.28. Appl., 10.10.27).- The inner of two concentric shells has a closed top on which w»ter is sprayed, thus producing a shower in the annular space between the two shells, through which the gas passes. The lower part of the inner shell is splayed out nearly to touch the outer, and a water reservoir is formed below th at point.

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

Apparatus for purifying steam , vapours, and gases centrifugally. W. Al e x a n d e r (B.P. 300,841, 25.2.28).—Forms of apparatus having no moving parts for cleaning steam etc. are described. B. M . Ve n a b l e s.

Apparatus for purifying and m oistening air.

A. ScirijcKnER (U.S.P. 1,691,827, 13.11.28. Appl., 15.2.24. Austr., 19.2.23):—A fan is provided with a hollow shaft through which liquid is supplied to the interior of a drum attached to the shaft and having porous walls to spray the liquid. B. M. Ve n a b l e s.

Treating sprayed m aterials with gases. In d u s t r ia l Sp r a y- Dr y in g Co r p., Assees. of B. F. Uh l (B.P.

296,421, 19.11.27. U.S., 1.9.27).—A spray dryer is constructed so th at the drying gas on entry is split up among a number of parallel passages the aggregate cross-section of which is greater than of the entry duct, but the passages themselves are of considerable length and free from abrupt changes of direction or cross-

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

Determ ining the contents of a gas. H . Sc h m ic k,

Assr. to Sie m e n s & Ha l sk e A.-G. (U.S.P. 1,691,138]

13.11.28. Appl., 3.6.26. Ger., 4.6.25).—In the method of determining the composition of a gas by radiation measurements, a selective radiator is used such th a t its emission bands overlap as little as possible the absorption bands of the test gas. A. R. Po w e l l.

Im pregnating brake bands, brake coverings, etc. W. Ot t m a n n (B.P. 279,496, 21.10.27. Ger., 21.10.26).—Silicic acid is precipitated in and/or on a band of fabric, e.g., asbestos with or without cotton and brass. The precipitation may be effected by alternate treatm ent with water-glass and acids or ammonium salts, or by the interaction of silicon tetrachloride and water or water-glass. B. M . Ve n a b l e s.;

H eat-treating furnace. A. Be s t a (U.S.P. 1,695,224, 11.12.28. Appl., 26.3.26. Ger., 28.2.25).—See B.P.

248,394; B., 1927, 554.

Apparatus for separating solid s [coal] from liquids. R. F. Kr a l l, Assr. to Wo o d a l l- Du c k h a m

(1920), Lt d. (U.S.P. 1,695,19-3,11.12.28. Appl., 24,4 26 U.K., 28.8.25).—See B.P. 261,850 ; B„ 1927, 64...-

(5)

Cl. II.—Fuel ; Gas ; Tar ; Mineral Oils. B r itis h C h e m ic a l A b s t r a c t s — B .

81

[Fuel supply control for] furnaces. J . Gordon &

Co., Lt d. (B.P. 283,522, 3.1.26. U.S., 12.1.27).

R efrig e ratin g p la n ts. A./S. Am u n d s e n Re f r ig e r a t o rCo. (B.P. 291,039, 21.10.27. U.S., 29.10.26).

Indicating [by audible signals] the exhaustion of gas-purifying substances [in respirators]. R . H.

and R . W. G. Da v is and C. G. Ro s l in g (B.P. 301,532, 31.8.27).

II.— F U E L ; G A S; T A R ; MINERAL OILS.

Hydrogenation and liquefaction of coal. V.

Influence of com position, pressure, temperature, and catalysts on hydrogenation. D . G. S k in n e r an d J . I. G ra h a m (Fuel, 1928, 7 , 543— 5 5 5 ; cf. B., 1927, 242).— A b o u t 30 different coals h av e been h y d ro g en ated a t 430° an d u n d er app ro x . 150 a tm . pressure ; a ro ta tin g a u to cla v e w as used, each charge consisting of 200 g. of coal an d 100 g. of phenol. The yields of (A) phenol-insoluble residue, (B) phenol-soluble, chloroform -insoluble pow der, (C) phenol-soluble, chloroform -soluble oil, (D ) lig h t sp irit boiling below 150°, (E ) w ater, an d (F) gas h av e been ta b u la te d , to g e th er w ith th e yields of p ro d u cts from th e carbonisa

tio n of th e coals a t 450° in th e G ra y -K in g assay. The p ara -b itu m in o u s coals (Seyler’s classification) appeared to be th e m o st am enable to hydrogenation, although exceptions to th is g eneralisation were observed. The ad d itio n of ferric an d nickel oxides increased th e oil yields ap preciably, bub th e m ost effective c a ta ly st for th is pu rp o se was am m onium m olybdate. T he results of th e hy d ro g en atio n of W arw ick sla te v itra in an d of th e residue a fte r e x tra c tin g th e coal w ith phenol a t 185° in d ic ate th a t th e e x tra c t is n o t converted into oil in th e process, b u t ap p ears in th e phenol-insoluble residue A . On th e o th e r h an d th e pyridine-soluble c o n stitu e n ts of a S taffordshire coal app eared to be com pletely co n v erted in to oil. F in e grinding of th e coal increases its ten d en c y to coke d u rin g th e process. The residue A is rich er in carbon, and generally, b u t n o t alw ays, poorer in h y drogen th a n th e original coal. On carbonising th is residue a t 600° usually only a pow dered coke was produced ; th e p ro d u cts from W arw ick slate v itra in a n d from G raigola coal, how ever, produced c o h eren t cokes, th e la tte r giving a m ore strongly swollen coke th a n th e original coal. T he pow der B is definitely a h y d ro g en a tio n p r o d u c t ; its yield varied from 0 • 6 to 3 3 % w ith differen t coals. On ca rbonisation i t produced a g re a tly swollen an d fragile coke. T he oil C contained 86— 8 7 % C, a b o u t 7 - 5 % H , and a b o u t 4 % O. The iodine v alu e of th e fractio n below 300° varied from 94 to 358, w hilst t h a t of th e lig h t oil D la y betw een 120

and 150. A. B . M an n in g .

Propagation of a zone of com bustion in coal.

V. Effect of tem perature. Tem perature of spon

taneous propagation. S . II. Je n k i n sand F. S . Sin n a t t

(Fuel, 1928, 7, 556—562; cf. B., 1927, 802).—The rate of propagation of a zone of combustion through a train of coal dust varies with the degree of fineness of the d u s t; the smaller the particle size of the coal below a certain limit the more rapidly is combustion propa

gated. No combustion at all occurs with particles above the limiting size. Other conditions being the

same, the rate of propagation increases with a rise in the original temperature of the coal. The temperature at which spontaneous propagation takes place was investigated by placing a cone of powdered coal in an electrically heated furnace maintained a t a constant temperature, and recording the rise of temperature in the interior and at the surface of the cone by means of thermocouples. Below a certain temperature, in the neighbourhood of 160—170° for the coals investigated, no combustion occurred; above that temperature spontaneous combustion took place.

A. B. Ma n n i n g.

Heating value of coal in nickel-lined bom bs.

A. E. St o p pe l and E. P. Ha r d in g (Ind. Eng. Chem., 1928, 2 0 , 1214—1218).—When the cal. value of a coal is determined by combustion under pressure correc

tions are necessary for the heats of formation of nitric and sulphuric acids, and when the material of the bomb is attacked by these acids further adjustments must be made. The amount of nickel removed from a nickel-lined bomb is measured by boiling the bomb- washings to remove carbon dioxide, titrating the solution with 0-liV-sodium hydroxide and methyl-red indicator, and then continuing the titration with phenolphthalein until the colour persists on boiling ; this method has been checked satisfactorily against gravimetric determinations. The heat of formation and solution for N i0-N 20 5-Aq is 54,500 g.-cal., or 2 -73 g.-cal.

per c.c. of 0-lA7-nickel nitrate. A series of experiments carried out with sucrose in a nickel-lined bomb, with and without appreciable amounts of nitrogen, showed good agreement with these figures on the assumption th at the surface contained both metallic nickel and its oxide. A correction of this kind must be made in the water equivalent of the calorimeter unless all nitrogen is excluded. When coal is burned, a further allowance is necessary for sulphate formation ; the total heat of formation of N i-0 2-S 0 2-Aq is 157,350 g.-cal., or 7-868 g.-cal. per c.c. of 0-liV-mckel sulphate, and is equivalent to 14 g.-cal. per eg. of sulphur. Results in an ilium bomb are compared with those in one with a nickel lining for coals varying in sulphur content from 0-45 to 8-82%, and the true cal. value agrees well in the two series of tests. R. H . Gr i f f i t h.

H ydrogen-volatile m atter ratio in American coals and its use in producer-gas calculations.

W. J. Hu f f (Ind. Eng. Chem., 1928, 2 0 ,1371—1372).—

A relationship between the hydrogen content of a coal and the percentage of volatile matter in it, previously found by Fieldner and Selvig (U.S. Bur. Mines Tech.

Paper No. 197, 1918) for 2000 American coals with calorific values between 12,000 and 14,500 B.Th.U./lb., has been expressed in a more convenient mathematical form, and illustrations of its application are given.

R. H . Gr if f i t h.

Average quantitative com position of Ruhr coal ash. D. J. W. Kr e u l e n (Brennstoff-Chem., 1928, 9, 399).—An average sample, containing the united ash from some 4000 samples of Ruhr coals, was made up of 4-8% soluble in water (mainly sodium, magnesium, and calcium sulphate), 41-0% soluble in hydrochloric acid (mainly ferric oxide and alumina), and 54-2%

(6)

B r i t is h C h e m ic a l A b s t r a c t s — B .

8 2 Cl. I I . — Fu e l ; Ga s ; Ta x ; Mi n e r a l Oi l s.

insoluble in hydrochloric acid (mainly silica and alumina).

Theaverage sample contained 41 •5% S i02, 18-4% Fe20 3, and 31 ■ 5% A120 S. W. T. K. B^raunholtz.

Characteristics of various kinds of coal, and the nomenclature of brown coals. W. Gothan, K.

Pietsch, and W. Petraschek (Braunkohle, 1927, 26, 669—674 ; Chem. Zentr., 1928, ii, 409—110).—Charac

teristics useful in the differentiation of peat, brown coal, and hard coal are enumerated. Chemical methods are not serviceable ; peat, however, is characterised by the greater cellulose content . A nomenclature and a descrip

tion of brown coals are included. A. A. Ei/dridge. Chem istry of the naturally occurring hum ic acids.

B. G. Simek (Brennstoff-Chem., 1928, 9 , 381—385).—

The humic acids were extracted from lignite writh alkali, and the alkaline solution was exposed to the air for several weeks to allow complete oxidation of oxidisable

“ proto ’’-acids ; the acids were precipitated with dilute hydrochloric acid, purified by electro-osmosis, and dried.

The final product contained (on the dry and ash-free basis) 63-63% C, 5-14% H, and 1-35% N. I t was separated by means of solvents into the following constituents : resinous acids (soluble in alcohol and ether) 9-57%, acids (soluble in alcohol, insoluble in ether) 6-09%, acids (insoluble in alcohol, soluble in pyridine) 15-23%, residue (insoluble in alcohol and pyridine) 69-11%. The resinous acids contained 2-13% OMe, which is sufficient to account completely for the methoxyl content of the original product. The separated fractions were treated with phenylhydrazine (to determine their content of carbonyl oxygen), and with methylating agents ; fairly well-defined products were obtained by the action of halogens and of nitric acid. The supposed nitro-compounds obtained with nitric acid were reduced to amines, diazotised, and coupled to give azo-dyes ; the humic acids themselves could also be coupled with diazonium salts. The various humic acid derivatives dye animal and vegetable fibres yellow and brown shades which are extremely fast to light. The above observa

tions lend support to Fischer’s conception of the arom

atic nature of humic acids. W. T. K. B rau n iio ltz.

W ater-gas equilibrium and the tem perature of the flam e. Y. Ka uk o (Fôrh. I l l nord, kemistmôtet, 1928, 167—168).—A method for investigating the above equilibrium in flames without the necessity for taking samplçs of the gases has been devised. The compo

sition of the fuel being known, the amounts of hydrogen, water, and nitrogen are functions of the percentages of carbon monoxide, carhon dioxide, and oxygen in the flame gases, the two former themselves depending on the oxygen content. The amount of heat available for the combustion and the temperature of the flame can also be calculated from a knowledge of the carbon monoxide and dioxide contents. Assuming th at water-gas equi

librium results in the flame, a relationship can be found between the variables temperature, carbon monoxide, carbon dioxide, hydrogen, and water vapour, and, by elimination of the two last-mentioned, two equations involving carbon monoxide, carbon dioxide, and tempera

ture can be derived, hence the composition of the flame gases can be determined simply from temperature measurements. Since the contents of carbon monoxide

and dioxide are dependent on the amount of air admitted, there is a dependence also between this factor and the temperature of the flame. Employing the above method the author finds th a t the water-gas equilibrium in an alcohol flame takes place a t 1300°. H . F. Ha r w o o d.

Flame m ovem ent in gaseous explosive m ixtu res.

O. 0. DE C. E i . l i s (Fuel, 1928, 7, 195—205, 245—252, 300—304, 336—344, 408-415, 449—454, 502—508, 526—534; cf. B., 1927, 354).—The propagation of a flame through explosive mixtures, principally of carbon monoxide and air or oxygen, has been studied by a photographic method. The movement of the flame surface in vessels of different shape, when the mixture is ignited either centrally or excentrically, is illustrated by numerous plates. A. B. M a n n in g .

Synthesis of higher hydrocarbons from water- gas [at atm ospheric pressure]. I I . D. F. Sm it h,

C. O. Ha w k, and D. A. Re y n o l d s (Ind. Eng. Chem., 1928, 2 0 , 1341—1348; cf. B., 1928, 434).—A catalyst containing cobalt, manganese, and copper carefully reduced in hydrogen under such conditions as prevented local overheating was used. The water-gas used was freed from oxygen, hydrogen sulphide, carbon dioxide, and water vapour, and finally from all sulphur com

pounds and heavy gases through a trap cooled in liquid air. A mixture of the fused nitrates of sodium, potassium, and lithium was used as the heating liquid in the therm ostat containing the reaction tube in which the catalyst was placed. Since the reactions evolve considerable quantities of heat, the therm ostat temperatures only approximate to those of the catalyst mass. The reaction tube was designed to reduce as far as possible this probable difference in temperature.

Experiments were made a t temperatures between 203° and 287° at space velocities from 120 to 260. At 203° 18% of the gas is converted in a single passage at a space velocity of 230. I t was noticed th a t the activity of the catalyst fell very rapidly (as judged by the amount of gas converted) as the volume of gas passed over increased, to reach a fairly steady value.

Passage of hydrogen over the catalyst reactivated it.

Most of the oxygen appears in the product as water, and the ratio H 20 /C 0 2 increases rapidly with decreasing temperature. At the higher space velocities and at the higher temperatures relatively more unsaturated hydro

carbons are form ed; with lower velocities and a t the higher temperatures, in general, more heavy hydro

carbons are formed. The total hydrocarbon products contain, according to conditions, from 20% by wt.

upwards of methane. In one experiment at 260° with a space velocity of 260 the composition of the hydro

carbon products was : methane 21%, “ gasol ” 45%, motor fuel 34%. The yields of hydrocarbons other than methane vary from 92 to 156 g./m.3 of hydrogen and carbon monoxide converted. Some degree of control can be exercised over the nature of the product by suitable choice of the variable conditions.

H . In g l e s o n.

Synthesis of m ethane from carbon dioxide and hydrogen. M. Ra n d a l l and F. W. Ge r a r d (Ind.

Eng. Chem., 1928, 2 0 , 1335—1340).—The equilibrium C 02-[-4H2=CH4-j-2H20 (gas) has been studied both

(7)

C l . I I . — F u e l ; Ga s ; Ta u ; M i n e r a l O i l s . 8 3

in order to determine the equilibrium constants and examine tlie efficiencies of two catalysts for the reaction.

The catalysts employed were nickel supported on porous brick prepared by reduction of the nitrate, and reduced nickel activated by ceria. Both forward and reverse reactions were carried out by the streaming method a t velocities Varying from 6-9 to 12-4- c.c. of exit gas (N.T.P., water vapour considered uncondensed) per hr. per c.c, of apparent volume of catalyst. The temperatures a t which the forward reaction was carried out varied from 521-8° Abs. to G65-6° Abs. The equilibrium constants calculated from these experiments according to the equation— Ii (in ° A b s .) = — 4-5787 1 oj[jp(CH,j).j)2(II20)/2>(C02).T)4(H2)], where p = molar fraction of the gas X total pressure in atm., are in good accord; c.g.,R for forward reaction at 648-1° Abs.

= — 16-51, whilst for the reverse change at 650-1° Abs.

= — 16-44. At temperatures below 595° Abs. the flow rates were too rapid to admit of equilibrium being established. In the experiments of Hightower and White (B., 1928, 147) equilibrium would appear not to have been attained. The results obtained by Pease and Chesbro (A., 1928, 707) arc in good accord with those of the present authors, which do not agree with those of Mayer and Henseling (A., 1909, i, 753) and of Neumann and Jacob (A., 1925, ii, 532). The free energy of methane calculated from these experiments,

—11,582 g.-cal., is in agreement with the value ■—11,617 g.-cal. found from the direct synthesis from graphite and hydrogen carried out by Mayer and Altmayer (A., 1907, i, 457). The reasons for the deposition of carbon in the catalyst are discussed, and it is concluded th a t the reaction talcing place between carbon dioxide and methane is a possible cause, although the mechanism is too complex for this to bo proved by the experiments.

A gas-sampling device and an automatic pressure- regulating valve are described in detail.

H. In g l es o n.

Ignition of m ixtu res of air w ith natural gas and with m ethane b y induction coil sparks. E. G.

Me it e r (Ind. Eng. Chem., 1928, 2 0 , 1353—1354).—

Natural gas, which contains varying amounts of methane, has ignition points in air somewhat different from th at of the pure substance ; a comparison of the two gases has been carried out under standard conditions ■with an electric spark as the firing mechanism. The natural gas contained 88-9% of methane, 7-4% of ethane, 2-4% of propane, 0-8% of butane, 0-1% of higher hydrocarbons, and 0-4% of nitrogen. The apparatus and method used were similar to those of Sastry (B., 1916, 682) and of 'Wheeler (B., 1920, 592 a), in which a variable spark gap was employed. The results showed th a t the most easily ignited mixtures of natural gas with air can be fired slightly more easily than any methane-air mixture, but the differences are never large. The optimum mixture contains 7-3—8-6% of combustible gas. 11. H . Gr if f i t h.

Radiation of heat from gas-lighting burners.

H . J. Ho d s m a n (Gas J., 1928, 1 8 4 , 794—796).—The energy represented by the light itself is a very small fraction of th a t supplied to ordinary illuminating agents. With electric light more than 95% of the

energy is dissipated as heat, and with a gas-lighting burner more than 99%. The distribution of the energy of the fuel, using several types of gas-lighting burners, was examined. The proportion of heat radiated down

wards was determined calorimetrically and found to be for a batswing burner 7-1%, of the cal. value of gas consumed; upright incandescence burner, without chimney, 19-7% ; inverted incandescence burner, with

out globe, 25 • 9% ; with globe 16-2%. These amounts could be increased by placing a reflector above the burner and by lining the top of the burner with refractory material, when the proportion of heat radiated

reached 37%. C. B. Ma r s o n.

Catalytic processes for utilisation of coal-tar crudes. A. 0 . Ja e g e r (Ind. Eng. Chem., 1928, 20, 1330—1335).—Difficulties are experienced in the eco

nomic working up of certain coal-tar crudes for anthracene by present methods, particularly when the content of this hydrocarbon is as low as 14%. When the tars are derived from cannel or other highly paraffinoid coals, the paraffins cannot be removed satisfactorily by any method used hitherto. In the process described the crude anthracene is vaporised and mixed with air, preferably by spraying it into heated air. The mixture is passed over a suitable heated catalyst and the impurities are oxidised without any considerable loss of anthracene.

It has been found th a t almost any selective oxidation catalyst can he employed, but th a t it is preferable to

“ stabilise ” the catalyst with compounds of alkali or alkaline-earth metals, or of metals of which the oxides are reduced with difficulty. E.g., a catalyst prepared from ferric oxide stabilised by potassium nitrate and supported on pumice when employed at 400—440° permits of the preparation of 94—96%

anthracene from a cannel coal-tar crude containing 25—30% of the hydrocarbon. Other suitable catalysts described include oxides of the fifth, sixth, and eighth groups stabilised by potassium compounds. If it is desired to prepare anthraquinone direct from the crude, after this preliminary removal of most of the impurities, the anthracene vapour is passed together with air through a contact mass suited for its oxidation. Such catalysts are zeolites containing vanadium tetroxide as one of the amphoteric oxides. A new solvent process distinct from the catalytic process described permits of the recovery of the carbazole and phenanthrene present in the crude anthracene. By one crystallisation of crude anthracene from furfuraldehyde, the anthracene con

tent may be raised from, say, 31 to 86%, and a t the same time the carbazole content reduced from 16 to about 6%. The anthracene recovery is about 96%, and such a product is suitable for catalytic oxidation to anthraquinone of a high purity. Carbazole and phenanthrene are recoverable from the mother-liquor, and are not lost as is the case in the catalytic oxidation.

H. In g l e s o n.

Critical tem peratures and oil cracking. R. H.

McKe e and H. H. Pa r k e r (Ind. Eng. Chem., 1928, 20, 1169—1172).—The temperature above which an oil can no longer exist as a liquid is of interest in connexion with cracking processes, and the critical temperatures for a large number of petroleum fractions, such as gas

b