US1138190A - Process for making atmospheric nitrogen. - Google Patents

Description

J. E. BUCHER. PROCESS FOR FIXlNG ATMOSPHERIC NITROGEN.

' APPLICATION FILED JULY 17, l9l3.

1,138,190, Patented May4, 1915.

BLASTMMP 6 24 5; 73 W 7 6' MW. s; fiaflwwww 8 ZZZ/P7572207.

E. BUCHER, OF COVENTRY, Eli-103E I UNiTED COMPANY, QF PROVIDENCE, 331-30511 ZSLAND, it. COEPORATIUN UH RHGDE ISLANFQ;

PROCESS F63, ENG ATMGSI;

ficati-tn of Le ERIC EIITLTRG GEN S Femi- L' Peton ted May 451,;

Dirt-51oz? act. this application filed. July 1?,

1913. Serial $79522 To all whom it may concern Be it known that I, Joni: E. Bocn'cn, oi Coventry, in the county of Kent and State of Rhode Island, have invented certain new and useful Improvements in the Process for FixingAtmospheric Nitrogen, of which the following is a specification.

This invention relates to thefixation of nitrogen and more particularly to an improved-'process'of preparing cyanogen compounds and derivatives therefrom, together with valuable by-products incidentto the production of such a compound or (301114 pounds. The process in' question is essentially syn thetic in character in its preferredfj form, and was suggested by my Workon the synthesis of cyanide and on my processes for purifying and preparing metals, i hich nitrogen plays an important part. cation for Letters Patent for these processes have been filed in the United States" Patent Office, being there identified as applications Serial Number 676,399, dated February 8 1912.; Serial Number 690,886, dated April 15, 1912 ;Serial Nuinber.710,758, dated July 22, 1912; and Serial Number 711,211, dated July 24, 1912. One of the equations repre-. senting the fundamental ideas of catalysis and reversible reactions upon which these four applications are-based is the following:

(1). 2N a; 20 N 4 iron 2 2NaCN iron. The pr sent application is'a division of my application entitled Process for fixing atmospheric J nitrogen 1, filed ()ctobcr 21,

1912, Serial "Emmet-26,924, which latter. application relates to a process'concerning' conversion of carbonates and the like into cyanids, as per equation: 3 h l v 2 Nc,CO,-l- 4Q+N,==2NaCN+iron this parent application having been previ ously briefly referred toinmy-said applice tion 711,211. The present'divisienal application reiates 'mo re perticularly to the synthetic production of cyanide, or the like,

from an alkali metal or its equivalent eup-" plied from such a compound as the carbonete of said metal when such compound 'isrelatively remote from the reaction zone in the parent "thereto, together with considerable of the matter set forth the parent application .ppiiwhich the oyanoi'en compound is produced. In the said app icati'on of which this a division is to he found presentation of much of the art relating to cyenid produe- 5 tion, and since this art is new of record in ""piication specific reference relating to said art, or serving particularly to point out the essential differences between the known. processes and that more especially referred to in the parent-application have been omitted for brevity. V i

The hereinafter described process in its severei aspects broadly aims to economically fir: otincsphez" nitrogen in a iorin whereby it he utiilzed either with or Without suhseqru it operations, according to the nature of the ultnnate product sought. 7 In the accompanying drawings, which form a hereof and in which like reference characters -esignate like partsthroughout the several views, I have exemplified one form of apparatus in which my process may be effectuatcd. It is to be understood. however, that this apparotus is but one of many invention to be regarded-as limited only by the scope of the ap'pendecl'claims.

.Descm'ptt'oa off appomtus, I 1

Referring to the drawing": Figure l is a so longitudinal verticalsection of mufiie furnace with retorts n posit on -therein.-',

2 is an eie tegtion of said. furnace;

the blast lamp being omitted. for convenience 0f illust'reition Fig, 318 a fragincmtary sec-' 9 tionor" one of thepip es or'retorts, the sec-- tion being talren on line 3-3 of 1. Fig. 41s a smnier section of a retort adapted for the use of air in the process.

Brickwork or other suitable material may be employed in the construction of the muille Lend one or more iron'pipes 2, serving as j charcoal and the body of.

' compound retorts, may extend directly therethrough. Caps or unions 3, serve to connect the ends of the retorts to the pipes4.-5; those desighated-4: being the pipes for supplying nitrogen or air as the case may be. The gases, notably carbon monoxid, evolved during the operation of the process are conveyed away via pipes 5. A blast lamp 6 or other able source of heat may be disposed in the preferably open end of'the muille and tli' apparatus should, of course, becapablegj f thrceexperiments nitrogen, preheating the retorts up to the reaction tom-.- peratures employed; which will be herein-g after very fully discussed. a

Assuming that the process 18 to be :e-E ducted in'such fashiona's to permit the led through 4:.-

of air, the, latter is and preferably first encounters one or-more masses 7 of charcoal .or other suitable 011%,: ml a co 0 paredby air through a tube'corr tainin hot co per, was passed, through a tube containing 1: e reaction mixture. do graphite'and 5 grams of sodium car creamer r, tube of one half inc gen consuming material. These niassespret-w diameter; At'. s temperature, there was an the: pines .t-Ezth l erably substantially points where-they are disposed ofthe air is obliged to. pass, theretlirougm I prefer to interpose wire gauze. ;;spac ng orsupporting screens 8, or the -like,"li etw een4tho mm 9 which is next encountered gases flowin' through the-pipe ,',or;.r'etort-; since it is esirable to away from the charge.

of the'operation,

from any other cause, remove a-po'rtion of such liquid compound (from said mass and thereby reduce the yield; The mixture 9prefei'ably consists of pulverulent coke, graphite, charcoal, coal, or the like, mixed with finely divided iron'and sodium 1 carbonate, or other inexpensive source of the metal forming the base of the cyanogen sought, or to be incidentally formed during the operation.

Considerations of emportcnce-l3efore considering the general reactions involved,

I desire to state that I cannot too strongly emphasize the importance of considering what would appear, at first-thought, to be merely minor considerations, but certain of which considerations are vital to the success oi": the process, and the overlooking of which has apparently led to the practical failure of the repeated attempts to effectuate the same. Non-observance of these considerations has led experimenters in this art jzp apparently partly succeed at one tinie, when by accident the conditions were propitious, and at other times to meet with total failure or with only such success as would not justify continued operation of the process on a commercial scale.

The present work isbased on a very large number of experiments, but I will here refer t ll.

the .fumes were due'to the 5' ativel wolatile free keep; the charcoal] thelgo tility of ;the carbonate itself, Iheat- During the course the elkelicc ir imd-inis very intimately a slomhut' stead 1 evolution of carbon mononid and some ,w ite fumes passed out of the with this} 1 fumesimparted v Sus acting that these ormationof the relsodium'rather'than to hgrams of vsodium carbonate with 30 Pp j hn a current of-nitrogen this test, the issuing gases did .not impart the slightest trace of yellow color to'the'flame at any time, nor could carbon m'onoxid be detected. Thislatter experiment with iron and sodium carbonate alone .(the graphite being omitted) proves that sodium carbonate is not sensibly decomposed .by fi nely fdivided iron at 1000G. nor is it volatile e'nou' h to given flame test at the end of the tuhe.

Experiment 1, (continued:) Upon cooling, the copper tube containing sodium carbonateand graphite showed a minute quan- H grm o f wdered-iron in "a similar tially supplied will be liquefied, and if the (i in charcoal is in contact with the reactive mass v .fiomezo auuiye to 1000 c. for fifty or. mixture, it may, by capillary action, or,

riment;1;,::10 grams of finely poms.

a-isteady thou Snot Ivery. intense yellow I tity, of whitematerial which had condensedon the cooler part of the tube; which deposit consisted at least partly of free metallic sodium. These facts show that at about 920 to 940 C., small quantities of sodium and carbon monoxid are formed according to attain a certain small vapor pressure, the revers ble reaction comes to equilibrium,

They are then sweptialong with the'nitrogen tioned tube were treated with water and.

tested for sodium cyanid by means of the russian blue test. Only traces could be deequation 3. When these two components tected even after the solution had stood for a day. The experiment shows that graphite,

. sodium and nitrogen yield practically no cyanid when heated to-the moderate temperature of 920 9'-l'0 'C. in the absence of a catalytic agent. And even hereit is pos sible that the copper in the tube orthe impurities (Fe) in the graphite may have exerted some catalytic influence.

Experiment 3: A mixture of 10 grams of the graphite, 10 grams of finel z powdered iron (Pharmacoptm Germam'oa 1V), and 5 grams of. sodium carbonate were heated in, an iron tube through which was passed a current of nitrogen. Vith the exception of adding 'iron as a catalyzer and substituting an iron for a copper containing tube, all conditions were kept asnearly as possible like those of the first. experiment. Atv a temperature of 920 940 C. as measured by the pyromcter, there was, in this latter case, a steady absorptionjof nitrogen and the escaping gas burned with the characteristic blue flame of ca'rbonmonoxid? Nitro gen was still being absorbed at the' end of fifty minutes when thefheatingwas discon" J tinned... The escaping fgases contained no fumes nor did they show the slightest trace of yellow color when led into'the burner flame, at any time during the experiment. This very sharp contrast with the experiment infwhich no catalyzer was used shows that free sodium did not escape with the gases Wheniron wasIused. The contents of the tube were then treated with water and the resulting solution was titrated with silver nitrate. ,It was found that% of the sodium carbonate had been converted into cyanid. Under the conditionsof this experiment, the velocity of the reaction was increasedat least several thousand-fold, even at this relatively low temperature, by the catalytic action of the iron with a consequent transformation of 60% of the carbonateinto cyanid in fifty minutes. A far more rapid formation ,ofcyanidmay be effected at, for example, higher temperatures, or by properly varying other conditions, as I shall hereinafter show. These and the further experimental results below mentioned, enable us to formulate a theory which is in. accordance with the facts and is of great service in connection with the process:

By means of Experiment 1, in which iron was omitted, it was proved that reaction 3 takes place at 92,0 to 940? C. (and to a less extent at even loivertemperatures). Now when comparativelyi small quantities of sodium vapor and on rbo'n monoxid are presout at this temperature, they tend to' form sodium carbonate and carbonand thus reverse the rcaction; establishing a chemical equilibrium. \Vhen no catalyzer is present, t1? sodium does not unite rapidly with the known for carbon. Hence a solid s'oliition nitrogen carbon, consequently is swept away by the current. of nitrogen, so that we have very little formation of cyanid. When, however, finely divided iron is'added to the mixture of carbon and sodium car.

bona'te, the mixture being heated to the given temperature as per Experiment 3, the iron Will become carburized by dissolving some carbon; thus forming a solid solution of carbon in iron.

Theory of erafio'm ln chemical work, it is often necessary to dissolve solids to make them reactive; and we also know that when substances are dissolved they very frequently become dissociated; These and many similar considerations point to the 80 conclusion. that if the very complex and ordinarily comparatively inert carbon can thus be dissolved it will not only' 'acquire mobility but perhaps may also become less v complex; thus approaching-the nascent con- 85 dition. Iron is one of thebest, solyents such as is obtained in the cementati'on p'ro'c ess of manufacturing steel, will form very quickly at the surface of the metal; provided that it is not already there, as in carburized iron. The conditions at this surface should be exceedingly favorable for chemical reactions and the above mentioned results obtained by the use of finely divided iron are in accordance with this view.

Presumably a part at least'of the operation takes place as follows: The small quantity of sodium vapor, formed according to, Equation and the nitrogen coiii'e' tact with the reactive surface of the carburined iron where they combine very. quickly with the carbon dissolved in the sur face of the iron, forming sodium'cyanid. The vapor pressure of the gaseous sodium, is thus reduced and consequently another p0rtion of sodium carbonate decomposes toreestablish the equilibrium. This new portion nitrogen and carbon at the surface: of the burized by taking up carbon from the carbona .eous in Contact tl'ierewith,loi from the carbon in solution in the'mass' of iron. The iron hence acts as a czrtalyzer by I undergoing a series of decarburiziitions and recarburizations; resulting in the efficient and continuous production of reactive car:- bon for the process. The very quick combination of sodium at this catalytic surface reduces the ooncenti' on of the sodiumvapor steadily; anl thus materially aids in producing con uous liberation dfsO- dium with the cons euent mrdinuousi for motion of sodium cyanid. This very simple theory, enables us 1 deal :ntcllirrently with the many conditiis which influence the process. Evidently the first requisite is to proklnee ezl loienh or ooaslytio or solution surface as pro lsi'olole onrl to maintain its elfioienoy our process. Even when fihe oondieions or surface onol contact appear So be correct or nearly at times a lapse of 10 or iii may CCCU.Z'1b8fQ1'6 any vigorous reaction place. This may be rl'uo, in. some oases, especially when working at a relatively low tempersturo, to the time, oonsuznori in corhurizing theLroactive-onn faces of the oorelytio material; and probably also so ohanges the relative elisposition 01'. fiuii and solid. constituents of their-reactive mass by, for example, theory of the oporenon must filrorefore be borne more while the actual prooedure is really a oomproznisehstvveen various news. At one temperature hoot; o/e RYQQrhBT' empero'lanro quits closers the first, onorner :c'antor gains the osoentionoy, sou so on Should. my theory faulty; which however I do 110i think is she ease, it at any rshesupplies' a Working hypothesis which enables us to achieve consistent and successful results.

, Sources and condaion of omi'al yzor, em- A line stale or division of the iron exposes o lorge'snrfuoe and. hence acts favorably. Ellmilorly o, fine state of division of "the carbon the quick oorhurizotion of the oyiiiingrthorough oontacf; at, What *1, solution surfaces, or gas prei' r to i The non carbon shoulcl be mixed floor-- oughly lfo; u ,e some reason, except in those oases herelrmf r referred to where the corhon is supplied, filnough the agency of a vapor It isof importance lo consider both the rehrtivs and the absolute size of the ps1 icicles of carbon and iron aswell as the 6X" tent to ix/hi1 they are in actual oontaoo. Tm cohrlyno agent, 6. 9. iron, if used in solid fo m should be or in surl.-other form as rl r no slhle the exposure o1": o, relatively enormous solution surface. Inroiculorly is thisthe when the operation is conducted. of, temp .11 lures nurterio Hy below the euteo: 'oiopoins of the carbons:ontnining material; if the iron he a coarse po'woer, insufiioient' surfsroewill usually be provlderh under such condition so permit of the process being oonrlurt oilloieinely. 'T'i on ll; is too finely cliviiled, there is some 1-3116.

army to pool; tootigghtly and therohypre'venl; diffusion of the gases and Vapors involved. (311. the Whole, however, I prefer to (iivide the on as finely as possible onrl to provide clififusioin in some suitable manner such as ill be heroine :or indicated.

l/lren Kills portloles of catalysis memorial relatively large, the surface is oorre sfiomlingly small and the area, of contact is j) to he 'hoo for quick onrl efilorent capillary action. I The re rector hocomes domisomotnnes ii; in the aggregate-*surigach,

- shape: smoothness or roughness quits finely powdered v to expose, or to renspherical smooth, they favor segregation;

the other hz'rnrh s n-zonal) rsnewsl of the carbon contentin thecatolytic surface. Under the indiqa'terl condltlons which I have found oonvement 1n effectuatin'g my process, when nitrogen and sodium were heated wlth in general, obtained when the iron was rela versed, 2". a. when the iron was ooarseon graphite fine. Thus iron Pk. G. IV, whl'ch is far finer than 100 mesh, gave very good iron, better results were m results when-used with graphite which had hundred 'mesh been. passed through a one was not nearly sieve butwhich on the Whole so finely divided as the iron.

result was; obtained when said fine iron was "sod with graphite of ,60 to mesh. When however, the graphite was of 20 mesh, with this very siderobly slower.

This series of tests, show, therefore, a dlslylnct maxlmum for the graphite o fijntermediate coarseness; as was toliave beenexpectecl; since when the partlcles are too finethe mass lacks poroslty and the nitrogen and-sodium vapor cannot soeas'lly penetrate the interior of the mass A whereby to efficiently contact with the re- 7, I herein broadly term 011 the other hand, 3 5

active surfaces (or as 1 3, reactive suriaoe). when the graplnte P31110168 are too coarse An even better fineiron the action was con'- the fine heavy particles of iron will tend-to;

drop through the interslaices some segregated. The latter action would, in extreme cases, be equivalent to remo the oatolyzer from the field of action,

find. that either of these two extremes may substantially result in the failure to produce.

and thus bewould .We should, further, not only nonsiderthe sizes of the,partib1es,but also their other, general physical propertiesi. -e. of surface, whether they are compact 'or sp0ngy,.1fe or irregular in shape, whether they are adhesive at the temperature of the operation, etc. For example, if the particles are coarse,' nor globular,- nonadhesive and while if, on the other banal, they are fine, irregular, rough and preferably slightly sticky or adhesive at the temperature of tho 0 oration,

bon for rho same, except where, in certain w oil the appended cloimssuch limitations-are specifically introtluced. For example, pulverulen't- 11011 may be produced directly in the reacting mass ltself from iron comthey obviously favor the contact an surface of increasing the pQtencyofrertain 35 phorus from the J 4s siunahly removes i 11 5 carbon and sodium carbonate may be prepared such proportions as to leave the iron, graphite and sodium' carbonate in favorable proportions for cyanid synthesis after the excess of graphite had reduced the 'liematite to metallic iron with the evolution of carbon monoxid. Underthesecircu'mstances the iron becomes reduced very readily (even if the solid carbon particles should not come intliorough contact with the iron ore, reduction would still take place completely because the molten cyanid formed reduces iron oxide with the utmost ease and even carburizes the iron at the same time) Further, if the temperature be sufiicieutly high, sodium vapor will be formed, according to Equation 3, which, of course, will act as a powerful reducing agent.

Iron scale (presumably I e-J3 reduced very quickly and'gaye a very satisfactory yield of cyamd; leaving the resulting iron,

after lixiviation of the cyanid, in excellentform for subsequent use with the process.

Thus use may be made of a Waste product (iron scale) or ore with the simultaneous production of cyanid, metallic iron, substantially nitrogen free carbon monoxid, and

" With the removal, in past at least, of imgiarities such as sulfur,

alumina, silica and phos- .,actin mass. 1 consider iol interest in the 5;, especially as the out in iron apparatus ache ii by ha c materials) temperatures with basic hence tends to remove the I i'NlPSm'nt elements, sulfur and phosphorus, as Well as acid forming clements in general, including silicon. It crew that this may be c" L steel phosn s or JllOSPl'Lil I etc, and. probably son LCL l1 ning ole 111611" in the form ot n1, i. The low tent peruturc, with consequent moderate reduc- {.0 tion, to say nothing of the strong alkalinei'iature of the charge, tends to produce a very pure lion and atthe-saine time affords a process for fixing atmospheric nitrogen.

. 6.0 1 Horton-The carbon may be supplied fmrn a'fvariety of'suitable sources and in addition to those mentioned, which. are solids, carbon supplying vapors may be used. Thus the hydro-carbons, e. g. petroleum, are available for use in-certain cases. It is highly desirable usually to substantially completely exclude'the 'oxygenof the atmosphere from participation in the reaction resulting in the productionof cyanid, since oxygen either converts the cyanid formed to cyanate; or oX-idizesthe iron and results in the production of ferro-cyanids or the like. upon subsequent lixiviation or even Worse, it may destroy the cyanid formed, with reproductionof carbonate... I

Thecarbon has greater freedom of motionthan one might at first expect. Its diffusion is not limited to mechanical motion due to illl'fiClilOD of graviiw, agitation of the luv, melting of solid material with oonseq sintering, Washing efiect on the particles by currents of liquid due to surface tension, change of concentration, capillarity, distillation of liquids, etc. It is soluble in the iron, or the like, used as acatalyser, and can diffuse either in the form of solid. or liquid solution. It may, in effect, carried as liquid, vapor, or even as solid the form of sublimate, by compounds such as cyanids, 2. g, sodium cyanicl. If these compoui'irls come in contact with iron lackin. carbon, a reverse action may take "place (Equation t), thus helping to carburize the mass or iron. Indeed, this imparts a mobility tmthe carbon such aswould be attained if the carbon could dili'use as a vapor, thus giving to the carbon, such as graphite, coke, charcoal, etc, in the tube, essentially the same kind of freedom that it would have if used. in the form of hydro- (32 icons. I believe that this may be a matter of great importance under some conditions of cyanid synthesis asit does not require differences in temperature f0 's manifestation, 6. g.

Nitrogen Moss A. of Mass 13 of N51 Neon.

' eNa,CO +-Fe+(l) For example, initlie above indicated dis position of masses of material, in the retort becomes carburized (the brackets indicating the respective spaced masses and the tube being indicated 11o tion of the tube or retort, Of course,

' taneously.

its, in which form thecarhon may be pres ent in mass A, at temperatures substantially of the eutectic point ofiron the instrumentality of the intermediate formation of a volatile Cy:

in the vicinity and carbon, through anid, to the B lo ated in. another porthe reaction canbe completed at A, first; thus getting rid of carbonmonoxid or, the two reactions may take Also carbon monoxi and sodium f rm according to Equation 3, and, if the reaction becomes reversed at the places mass where the temperature is lower or the concentration. of carbon monoxid is greater, a mass of sodium carbonate and carboni'will be de osited, in effect, as though the carbon had istilled as free carbon. .This deposition of carbon may hell at times when'the process is not procee ing as rapidly as compoundswhich may result or other base of the cyanogen I formed, during the course of the might be desired. n

Alkali mtal.-The source ofalkalimetal compound process, is preferably some inexpensive compound such as sodium carbonate, sodium bicarbonate, sodium hydrate, toemploy initially equivalent, and in those of theclaims herein set. forth whi h are of sufficient scope to be readable upon a process using initially free alkali metal or its equivalent as well as uon alkali metal other than initially free (in other words, where the alkali metal,'or a volatile compound thereof, is supplied from a source of thesame, relatively remote from the reaction zone) are not to deemed as being limited to alkali metal, or compound of the same. 7 With respect to sodium bicarbonate I particularly desire to call attention to the fact that I have successfully used the moist bicarbonate which comes from the ammonia soda process; and this without previous drying. Indeed, very many impure alkali metal from various techinal processes can be'converted into pure cyanogen compounds. For example, mixtures of alkali metal hydroxids, carbonates, acid carbonates, acetates,/oxalates,'"etc., can be used directly if iron, oxide, or hydroxide, oror- ,ganic salts at B; equation 4 Stassfurt, Germany,

separately, lace simul-' or the like, but it isipossible free alkali metal or its be such supply of, the like, from an existing I of iron, carbon or organic mat ter in general be'present; and no contamination of the alkali metal cyanids canoccur since the substances of the classes mentioned are so transformed in the process that the only negative-radical remaining will be cyanogen. If more than one alkali metal be present, however, a mixture of alkali metal cyanids will result. When the cyanid transformed into ammonia obtained is to be as hereinafter described almost any other impurities may be present without affecting the purity of the product, providing suitable precautions. are taken. sulfates, can also be used with much advans tage in my process. Potassium sulfate is obtained extensively from the deposits at while sodium sulfate is obtained in large quantity. as a by-product from the action of sulfuric acid on sodium compounds, such as chlorid.

- I find, that in my process sulfates may readily be converted into cyanids by'the .following procedure: Pulverulent graphite and sulfates e. 9. 1321 80, ,or K SO, may be heated in ironlpipes to temperatures suitable for cyanid formation. 'At'this temperature the valkali metal sulfates are reduced rapidly to sulfid and carbon monoxid (which is substantially pure) Thus:

The sulfidmay now be converted into carbonateevenviwithout removing it from the apparatus or separating it from the carbon with which it is mixed. This may be done by allowing it to cool to a suitable temperature and then passing a current of moist car-- bon dioxid through the mass, or the water directly to the mass containing the alkali metal sulfid and carbon before passing the carbon dioxid through i the mass. The chemical action, in the case of sodium sulfid, may be expressed thus:

The mixture of sodium carbonate and carbon, thus obtained, is especially adapted for. m Y process since, if desired, 'it may be mixed with finely pulverized iron followed by-subsequent heating with nitrogen "at. a suitable temperature to convert the Alkali metal in' suitable proportions may even be added alkali carbonate i messes into cyanogen com ands per Equation. cyanid r'ormatihn J'ly to the mixture of sodium sulfate carbon, before I have shown that the transference of carbon from one separatemass to another in a tube or retort is possible, and will now consider the somewhat slmllar but not heating. strictly analogous transference of sodium.

Mass 0 of Mass D of QLL, r ce, +0; 1a, (Fe) Nam +60 1* e rQ preferably carburiz'ed or mixed with C. l V

dium and carbon."

supplied by mass frequently used this mixture of carbon and iron With rather ineffective reaction mixtures to absorb the sodium vapor from the escaping gases, thus doing away completely With loss by volatilization, and the danger of explosions from free sodium when the masses were lixiviated. It is obvious too,

that sodium carbonate, for example, may be distilled over, from a mass of the same into contact With the material presenting the reactive solution surface. I am of the opinion, however, that the hull: of the sodium C to mass D passes ever as free or metallic sodium in vaporous form. At 920 to 940 C. this sodium vapor would be formed quite slowly O and be carried to D by the nitrogen uhich at this te1uperature would usually make up the greater lliassll being porous,

part of the gas.

muss D, capillarity probis also, of course,

ablyplays an important part in both cases.

I gen current through agent c. f heat to ii is":

An extended film of the liquid source of the alkali metal he forms on the carbon particles and this I shell, for convenience,

term (Whether here or, in other cases, on

the iron as well) a re; tive film since it decomposes under the ion. oi a suitable l' r the alkali metal. Presumably ii the tile: 2 is very extended the sodium vapor quick saturates the free space in the porous mass '3, thus bringing about a condition of equilibrium. The rate of the sodium vapor would 1, en be determined practically by the flow or the nitrothe tube no matter whether the masses in C and I) were inch nitrogen to produce so --fect would bedecreased a apart or many feet apart-"- For example, if the nitrogen were passed through a one half inch iron pipe at'a temperature of 9204940? or evensomewhatlower, at therate of about 100 cc. per second, it would take a very long time to'get a substantially quantitative yield of cyanidta't D; and this in spite of the fact that cyanid formation, Equation 4,- takes place practically instantaneousl at this very elficient catalytic solu 1 tion sur ace at D Equation 4- is apparently of the fifth order, when We consider it as taking place from right to left forthc conditions at about 900. and the Velocity of this retarding reaction would hence vary viding that it is of this order. Hence if the catalytic or other action were efficient enough to reduce this vapor pressure down to one tenth of its former value, the retarding of;-

thousand-fold.

as the fifth power of the vapor pressure of the two gases, pro- I amaware that reactions of high order are rare (as statedby Nernst onpage 560 of his Theoretical Chemistry, 4th edition,

New York, 1904) but even if the reaction. in

question were only of the second order the decrease ofthe retarding effect *WOllld yet be ahundred-fold; whilein the lowest order,

e. the first, said elfect'lwould still be tenfold. This demonstrates that in any case the reduction effect is large: and it may be, indeed probably is, dicated.

In the experiments above referred to, the rate of dillusion of the sodium vapor was about a million times as great as the velocity of the nitrogen current. Therefore when the components of the reacting mixture are finely powdered, the sodium molecules have such a short distance to travel that the rate at which the sodium comes in contact with the reactive solution surface is largely deter-.

mined by the enormous molecular diffusionveloelty rather than by slow sodlum laden nitrogen current.

Let us now consider 'themasses C and D.

that of the relatively enormous, as I have into be superimposed; In this case the pan uniform "ca s o3? latent oi vaporize time. T flowing of molten mutter, e. g. sodiuincsrbonsts, i'roin whatever cause, must; have much eilect'ss' shown by the above con 'deretions. Flowing of liquid may even csuse segregation, by washing sway particles of carbon or iron, and thus cause loss of efficiency. @n the other hand it may be caused to, or may even inadvertently was; the particles into-more ed ventsgeoue positions, thus causing incneesed emciency; Also the molten materials may, as conditions determine, either flow ews r from or else toward the reacting mixture; and this Low oi? liquid may therefore seeeither 'detriincntslly or advantageously,

' For example, I have noticed that when con.

. ture, about 180.

the flowing of the liquid by gravity and the conditions which modify these,

ditions were not quite right, beneficial re suits were frequently obtained simply rototing the tube containing thereection mix This is presumably due to consequent surface changes. I regard the efiects due to surface tension or to relatively minute differences in surface tension, as as to that phase of surface tension which i generally termed cspillerity, and also theas of, much importance. 7 I i As the composition of the molten alkali mixture is constantly changing during the process, .tbe suriece tension is presumably changed likewise, thus;tendingtoicsuse rnot on of the particles in o well knowninsn-- ner. The finely powdered, porous reacting uflords exceptional opportunities for capillarity to exert its influence. The p0w-' dercd ir s oi carbon and iron will take up by csnillsrity the liquid independently'or' separately supplied thereto, or will similarly re-tslre up the liquid which may liRVe drained by gravity to the lower portions thereof after the content of liquid remaining in the drained "-ortions has been in whole or in port removed; the action being not dissimilar to t We in which a. lamp wick. takes up oil. in this porous mass of carbon and the liquid comes in contact with the very large surface of the iron,-nnd inci' dentally, of course, of the carbon; while? nitrogen can also diffuse to this surface very rapidlyiwhich obviously tends under the prescribed conditions to favor the formation of cynnid; the films of liquid more or less rapidly beingdissociated to yield the free sodium, which latter mag/ either react where liberated or elsewhere on the surface. refr tion or free sodium per unit ortime, together i s can the nitrogen molecules penetrate it to reach the reactive suriace of the csrbon sup-- plying iron. l fhen this film is too thick the nitrogen cannot well penetrate and the reactionis impeded. Further, the more czten sive the film surface, the greater is the libero of course, with ii correspondingly accentusited evaporation of the liquid compound itself, or of its decomposition products. If too much molten liquid is present, the pores or interstices will, ofcourse, bemo're or less filled or choked therewith, thus preventing the required contact of'the gaseous materials, such as nitrogen cndsodinm vapor, with the catalytic solution surface. We may regard the nitrogen as burning the carbon and sodiuinto sodium cyanid, and if there be either insuficient catalytic solution surface or oil-inadequatelyreactive or insuificiently extensive film this peculiar combustion is retsrdsd or in extreme cases may be almost wholly prevented. l.

lliesbove considerations concerning the mobility, especiollz that duextoflcapillarity, within the reacting mass led me to makes considerable number of experiments of mixture of 40% *of graphite of lllO-incsb,

40. finely powdered iron"'(Ph. 0. IV}, and

559% of freshly ignitedsod-ium carbonate was prepared. A flat bottom iron retort 70 mm. by ill inin. wusettached to a long piece'of wire so thatit could be inserted into aflong 'ipe which .was-lieatcd-to the desired tempereture and through which a current'of nitrogen. was pessing. v r Experiment i: One half a-grembithe abuse-reactionmixture containing carbon,

iron, andfsodiuni carbonate was tamped into the retort in s niniormlayer. The retort was som ones intosth e tube which was heated to IO'YO C. Ndfnrore thenlmninute was allowed for-it to come to the reaction temperature, and it was thenallowedtb'ief main for five minutes more in the heated nitrogen. It was then withdrawn to the cold part of the tube and allowed to cool in the current of nitrogen. Upon lixiviation, so little'oyenid was found that it could not be titrated accurately with silver nitrate solution. (This experiment was repeated with the exception that the tube was heated-to- 1000 C.-the result being the same.)

Experiment 5: The retort was again charged. with one-half gram of aforesaid mixture of sodium csrbonate,= iron and graphite, and six-tenths of a gram (an, equal volume, therefore an cqusd depth of layer) of a mixture of eqnal'partsbf the 100'mesh graphite .snd the iron (Ph. 641V) was tuniped on, the surface of the reactive mixw turc containing the sodium carbonate. This was pushedinto the tube containing nitrogen posted substantially as per Experiment' l, at. V,

9%" G. .butI witnout the tamping material. Her tligquuntity ofycyunid formed was too small to be -titrated with silver nitrate $0111 tion.

Experiment 7 This experiment was exactly like Experiment with the exception 5 that twice as much (one and two-tenths grams) of the above carbon-iron tamping mixture was used, 2'. e. the layer of tamping material was twice as deep as that used in Experiment 5'. In this case, I found that about 50% of the sodium carbonate had been converted into sodium cyanid in five minutes at 990 C.

Experiment 8: Experiment one and two-tenths grams tampingmixture were laced in the bottom of the retort and the 've tenths grams reaction mixture formed the upper layer. The result was sub..- stantiall the same as that of Experiment 7, e. f hlly 50% of the sodium carbonate was converted into sod'um cyanid in minutes at 990 C. (A?!) another time the same yielded fully 40% in two minutes),

Experiment 9: In this case the quantities of material usedwer'e exactly preceding Experiment 8, but they warp thoroughly'mixed instead of being used in layers. In this particular experiment the yield of eyanid was about 40% of the theory, in five minutes at 990 C. i Experiment 10: This experiment was practically a repetition of that described under Experiment 6, and is cited merely as an exception, since in this case, a small yield of cyanid, to wit, was obtained, which demonstrates that even under what appear to be identical x'zonditions, some variations in yield/may egcur. In the case in point, the cyanidformatmn may have been due to some condition such as lack of uniformity in. the mixture, all. parts not being uniformly saturated, or in other words, some suiiiciently efi'ective film surface was ing the course of the operation, once being 'present, would tend to extend itself, due to capillary action, or circulation induced by changes in com osition in the liquid phase.

I have stat-er in the rfecedi'n" ex eriields were obtained, that these Thia' unseopcrain each then that the period ext. and to one-half hour.

.Utantially no r 1 the retort in tube, while further little, if any, carbonate remained, which in view of the preceding shorter term opera time indicated that eyanid had been formed and had thereafter volatiliaedi .,fully This experiment was like 7 with the exception that the: sodium carbonate isapparently C. while that. of. potassium "carbonate is Experiment 12 This five ' titration was 22%.

those in the '.over in five minutes at 1060. 0,

present which duriid was found in the The 'followingpxperiments: are of interest as showin the efiectiveness of the process at relatively ow temperatures:

Experiment 11: This experiment was substantially like Experiment 8 with the exception that in the reaction mixture, one half of the sodium carbonate was replace potassium carbonate' The temperature of the operation was 840 C; and the cyanid yield in the residue, upon titration, and at the expiration of a thirty minute run was In this connection it may be of interest to about 860 about 8809 0.; The eutectic point' of; the mixture is about 69.0? C. I experiment was a repetition of Experiment 11, except that the temperature of the operationWas 780". C. and the time-forty minutes. The yield by Experiment 13: This experiment was a repetition of Experiment 12, save that the temperature was 730 and the time forty-five minutes; Yield bytitration.some-' what over'2%. Obviously as the temperaven unit of time decreased. Correspondmgly, other things being equal, more ele vated temperatures afiord markedly greater yields per unit of time. Thus I have converted 45% of a given quantity of sodium carbonate into cyanid in two minutes, and

The efficiency of the c'atalyzer in lowering the temperature ofcyanid formation and increasing the rate of itsformati on is even more strikingly shown by comparing the foregoing with the {following/statement ,of Dr. Ewan, in Thorpe-ls Dictionary of 4 1)- plz'ed Ohemz'stry, 'revised edition, vol ""11, 1912, page 196': y

A few. temperature m as rementsjwhich the writer made! with afplal inum rhodium thermocouple showed that potassium vapor is first evolved from a mixture of potassium notethatthe melting point of .ture-was lowered the cyanid formation per a carbonate and charcoal at about 1350 and 1 heated in'twenty-five gram lots in a half inc-h pipe to 990" with the nitrogen.

Experiments 5, 7,8 and 9 gave very rapid conversion o-E carbonate into cyanid. Presumably in Expei 5 and 7 the carbonate {osmium} n1 e ed then penetrated ciently converted 'ment 8 Where the -aided by gravity,

by capillarity' into the upper layer of tamping material, thereto be rapidly and efiiinto cyanid. In Experireacting mixture constis tuted the, upperlayer, the same result was attained'by means of the capillary forces While in Experiment 9 the same result as in 8 was attained by thoroughly mixing the materials before they were tamped into the retort. Also When. the very efficient reactive mixturejvas used in the thinner layer the yields vitii'edfrom almost nothing (4% and 6) to a comparatively poor yield in. 10; presumably because the slight depth did not pemnit of sufficient drainage of the molten sodium carbonate from the upper'layers of the mixture so as to provide suitable reaction conditions. ()n such as twenty-five grams was tamped intoa onehalf inch iron p1pe,.presumably a, portion of the molten carbonate in'the upper portions of the mixture drained to the lower portions so as to leave conditions in the upper'partoi the massvery favorable for cyanitl fomna tion thereby automatically producingcondiintentionally in Experiments 5 and 7;

tiolls substantially Use ofappamt'ueskown by way of emcee plz'ficotz'om Ass uinmg now, serum conditionsprescrlb'ed have been observed in the disposition of material in the furnace shown .in the accompanying drawing,

.111 this case amass 9,,ofi'intimately'mixe'd,

" titatively,

adequate current of nitrogen is flowing through the tubes 2, each of the latter having finely powderediron, sodium carbonate and graphite in place therein. Theactions and reactions take place as above described, sodium cyani'd is formedi'n the interstices of the masses 9 and carbon monoxid 'gas'fi'ows oil together. 4 with some excess nitrogen,

through the wees-5; It is to be understood,,

of course, that it possible to operate quanso that snbstantially all of the nitrogen, carbon and'alkali metal compound using air is are converted'directly into cyanidi;v and all of thiscan'be done below theinelting point of copper. The cyzmid which may boob tain'ed from the residuewof the masses 9 is substantially 160% A exceedingly. soluble in waver, lix viation affords a convenient means for separating it from the residues of the reaction. Air may be used in lieu of nitrogen and the ment of materials and parts shown in Fig. l has been found a convenient one in such cases. Save for theprovision of the oxygen consumingcharcoal 7, and separating screen 8, the operation and appa-ratus is substan-- tiall c-thee same as in the case ust discussed.

lgtunay be well to note, however, that when it advisable to operate at a slightly higher temperature,say 50 C.,,tl1an whengusing nitrogen. The charcoal comsimilar to those provided.

much less, and

and that an cases to operate for a short time only upon a pure and as cyaniol is I arrangeread ly dissolving carbon,

oxid passes on to the reactive mixtureand the nitrogen reacts therewith, as before. The

heat necessary can be produced in the-fut:- nace tube or retort itself, thu'sahnost en tirely avoiding Wear and tear on the apparatus. I

Time factor.1n the art of cyanid synthesis, We find frequent'references to the yieldsobtained, but much less often to the time required for effecting the changes. I wish-to emphasize the very great importance of this time element and have aimed coinv stantly in developing my process to make it an' expeditious one.v When it is considered that the cost of labor, wear and tear of apparatus, interest char loss of heat by radiation, conduction, and hot fluegases are, in general, direct functions of the time an operation requires; We realize that the time factor may become, sometimes, of even greater ii nportance than the ultimate or practicable time given for cer i For example, the tails processes is sometimes ten. hours or more, with alleged yields of perhaps 50% or under very drastic'temperayield.

ture conditions. L'My process" "a'fiords far.

greater yields, and-at 'vsrymoderate temperaccordiug' the conditions selected. In"

that such an expeditiousprocess is an enormously advantageous one even ii it were atures, m from-ftwoto twenty-five minutes other-Words, my "process Will easily produce as much cyanid 1n several days as such processes can in a year. From this, it is evident equallyailected by the above items of eX- pensefwhichhowever, is not the case. It is also evident thatrm many cases it is desirable to sacrifice the yield somewhat providing a considerable saving in time will result. Thus it may be found advantageous in certain given mixture with the object of producing, let us say, a. yield of 50% gthe-r'eafter removing the cyanid formed in any suitable 1nanner and re-using the residue either alone or mixed withfresh material or materi 11s, 0. 9

iron and sodium carbonate, as desired.

Resum.To epitomize, therefore the features, of the process which, when observed,

lead to consistent'resultsand commercial success in the production of cyanid.

'(a). A material, 6. 51. iron, capable of must be employed as afcatalytic agent.

(5) This material should "be present in such quantityand should be in such. condition as to alford an abundant solution or reactive surface. I

(c) This surface should be maintained. By'this I do not niean that necessarily the same identical surface must be maintained,

although even this'is preferable, but that the observed is that the metallic vapor mold? extent of available surface considered as a Whole should be substantially maintained and that the carbon present therein should be maintained in suliicient quantity to perinit of an energetic and practically continu ous reaction taking place between said car bon and the nitrogen and free, or probably free, alkali metal.

(cl) The carbon should be present in such quantity and so disposed with respect to the carbon dissolving metal or agent thatthe reactive surface of the latter may be ade-. quately and substantially continuously supplied. To this end also proper contact must be effected and maintained between the can bonaceous material and said metal, unless the latter be initially suliiciently carburize'd to permit of continuous operation for a sufficiently extended period of time. I (e) The source of the alkali metal, or base of the compound. sought, may either be intimately mixed with the catalytic material or otherwise. The essential zt'eature to he cules must be developed or besupplied'in adequate quantity and must either be-in contact With or be able to make contact with the carbon supplying solution surface at the same instant as the nitrogen molecules.

The reactive solution surface must not only be extensive and pro erly carburized but it must be accessi is to the 7 molecules of tho case or vapors-participating in the react on. In other Words, it must not be clogg' l. up or covered with. toothick films of liquid. When, therefore, l he source of the base of the cyanogen compound sought is" a material. which is molten at thetemperature of the operation, a. g. sodium carbonate,

and this liquid is present in erlcess, ar sufiigcient extent-' of effective solution surface must still preserved by a-liording proper drainage fiicilities, or the equivalent thereof."

(g) The mass should be suiliciently porous to permit of the, least, moderately free passage of nitrogen therethroyigh whereby not only to supply nitrogen in adequate quantity to a suilioicnt extent thereof toiavor a rapid production. of cyanid'; but, also, to su'liiciently dilute and preferably to even dislodge, or sweep away, the deleteri ous, inert carbpn monoxid from the reaction surfaces. 6

(1 b) The temperature of the operation must be such as to afford the requisite molecular activityv The principal point to be observed in connection. with the temperature that at temperatures materially below'a fairly bright red heat the contact relations existing between the catalytic material and carbon must be more intimate and complete and the effective reactive surfaces more extensive than at higher. temperatures. In other Words, What We loose in temperature, mustbe made up in some other way. The

doc I lower temperatures ofcourse, tend to prolong the life of the apparatus. p K

I General wzmarlca-0wingto the n'umer ous possibilities of the process, I have-only described some of the more important steps involved, hence I Wish tobe limited only by' the general spirit of the above'disclb'sures and by the appended claims. For convenionce, I have described most of the experi ments, and written. the corresponding equa. tions, for sodium compounds; but these descriptions are intended to apply -to alkali compounds generally, and, Where applicable, to metals capableof performing like functions in the process.

In certain of. heappended' claims I have used. the term vapor and in such cases 'yvhere not otherwise specifically limited or restricted. this term to be regarded as of suilicient breadth to cover, for example, both alkali metal vapor and the'vapor of an alkali metal compound, 0. 19. sodium oar-- bonate, etc. i

Having thus described my invention What Iclaimisz, 7 1. The processjof fivin atmospheric nitrogen which comprises eifecting afliberation .of alkali metal" vapor from-a compound 01 I the same, substantially preventing the liberated metal from exercising a reaction retarding vapor pressure upon theresidue of said compound "by interniingling a currei'it of free nitrogen with the so liberated alkali metal and reacting upon thejinixture with carbon held in solution in'a mass of catalytic material disposed at a point'relatively re mote from theplacc where said alkali metal is liberated, to form a cyanogen compound oi s aid alkali metal. The process of fix ng atmospheric nitro- 11 which comprises eil'ecting the liberation of anza'lkah or alkaline earth metal capable of acting as the baseoli a cyanogen comvapor-with. saidfcarbonin solution to directly form acyanogem compound ofsaid alkali metal.

3.-The p'rocessof fixing atmospheric n-itr0- gen which comprises effecting the'lib'eration in vaporous condition "of an alkali "of alkaline earth metah froin nass-o;tf"material-condining said metal as one-ofthe constituents thereof mssiu current of freenitro en.

in contact with sa' 1 mass and thereby forming a mixture of u rogen and the vapor of said'metal, conveying said mixture into inti mate C(Jl'ltltCt with a mass of catalytic ma;

terialcontaining carbon in solutiomand rcactiiw upon said. carbonpwith said heatedmass of catalytic material having an extended solution surface, and ejtlecting a direct reaction at said surface between said metal nitro en and carbon tos'ntheticall' form said cyanogen compound.

5. The process of fixing atmospheric n trogen which comprises bringingan intimate mixture of free nitrogen and the vapor of an alkali or alkaline earth metal, capable of acting as the base of a cyanogen compound to be formed during the course of said process, into close contact with extended surface of catalytic material containing carbon in solution, reacting at. said suri'ace upon the dissolved carbon witli said metal andnitrogen to synthetically form said cyanogen compound, and continuing said reaction by abundantly supplying said surface with freshcarbon as the content of dissolved car-- bon therein is reduced by saidreaction.

6. The rocess of fixin atmospherio nitro' gen whic comprises bringing an intimate mixture of free nitrogen and the Vapor of an alkali or alkaline earth metal, capable of acting as the base of a cyanogen compound to be formed during-the course of process, into close contact with an EZZJEZiflGi. surface of catalytic material containing carbon in solution, reacting at said surface upon the dissolved carbon with said metal and nitrogen to synthetically form said cyanogen compound, and: maintaining the efiiciency oi said surface both with regard to its extent and to the carbon contentthereof. w 7. The process of fixing atmospheric nitrogen which comprises bringing free nitrogen and an alkali or alkaline earth metal. in

molecular condition which is capable of acting as the base of a cyanogen compound to be formed While said nitrogen is being fixed simultaneously into intimate contact with carbon dissolved in a heated mass of cute. lytic material having an extended solution surface, and efi'ecting a direct reaction said surface between said metal, nitrogen and'carbonto synthetically form said cyanogen compound.

8. The process of fixing atmospheric nitro gen which comprises bringing free nitrogen and an alkali or alkaline earth metal in molecular condition which is capable of act ing as the base of a cyanogen compound to be formed whilesaid nitrogen is being fixed, simultaneously into intimate contact with carbon dissolved in a heated mass of finely divided catalytic material having an exhfl" process of fixingatmospheric nitro an alkali ftrogen which comprises efiecting tendedsclntion surface, and effecting a di "rect reaction at said surface-between metal Urogen and carbon to synthetically torn; sa d cyanogen coinpcimri.

. 9.; lhe process cit-lining atmospheric nitrogen which comprises bringing tree nitrogen alkaline earth metal in molecular condi' n Whichis capable of acting as the base of cyanogen compound-to be formed While said. nitrogen is being fixed,

siinultaneously into intimate contact with carbon dissolved into a heated mass or" iron leaving an extended solution surface, and efiecting a direct reaction at said surface between said first mentioned metal, nitrogen and carbon to synthetically form said cy anogen compound. 10. The process of lining atmospheric nitrogen which comprises bringing tree nitrogen and an alkali or lilltlllle earth. metal in molecular condition which is "pablc of acting as the base of a cyanogen compound to be formed While said nitrogen is being fixed, simultaneously into intimate contact with carbon dissolved a heated mass of a metal capable of dissolving carbon and having an extended solution. surface, and ef ecting a direct reaction said first mentioned metal, nitrogen carbon to synthetically form said cyanogen compound.

11. The process of fixing atmospheric nitrogen which comprises efiecting the liben ation of an alkali or alkaline metal.

capable of acting as the base of a cyanogen compound to be formed while said nitrogen is being fixed, from compound said metal, disposed in the form of an ext-cn'dediilm, sweeping the liberated metal in vapoious material containing carbon solution, by means of a current of free nitrogen and re acting upon the mixed nitrogen and metal vaporwith said carbon solution to directly form a cyanogen compound of said alkali metal.

12. process of fixing atmospheric nivigorous reaction between free alkali or alkaline earth metal atmospheric nitrogen substantially free from oxygen, at when participating in the reaction, and bon solution in a mass of catalytic material cape bio of favoring said reaction, an extended surface of said catalytic material, whereby to directly form a cyanogen compound and continuing said reaction by supplying fresh, carbon to said surface to replace that removed therefrom by said reaction.

13. The process of fixing atmospheric nitrogen which comprises effecting a vigorous reaction between iirec alkali or allralinoearth metal atmospheric nitrogen substantially free from oxygen, at least when participatform toward a separate. mass of catalytic ing in the reaction, and carbon in solution in I of favoring said reaction, at an extended surface of-said catalytic material, whereby to directly form a cyanogen compound, and

continuing said reaction by supplying fresh pheric nitrogen substantially free from oxy-,

gen, at least when participating in the re.- action, and carbon in solution in a mass of catalytic material capable oi favoring said reaction, at an extended surface of said catalytic material, whereby to directly fprm a cyanogen compound, and continuing said reaction by supplying fresh carbonto-said surface to rep ace by said reaction. Y

15. The process 01" fixing atmospheric nitrogen which comprises treating a comound, which contains an alkali or alkaline earth metal capable of acting as the base of a cyanogen com ound to be formed while said nitrogen is eing fixed, to obtain a va-- por therefrom, by subjecting said compound that removed therefrom.

to heat and to capiilary action, the latter whereby to form an extended film. surface of said first mentioned compound at which said j Vapor is produced, and thereafter bringing said vapor into contact with a mass of cata lytic material containing carbon in solution in an extended surface of said material and vigorously reacting upon said vapor simultaneously with free nitrogen and said bon, to form said cyanogen compound.

16. The process of fixing nitrogen whichiiw comprises bringing initially free nitrogenv into contact with carbon dissolved in cata lytlc, material presentlng an extended, rough, solution surface, combin ng the dissolved carbon present in said surface with

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