June, 1913
T H E J O G R , Y i l L O F I N D U S T R I A L AA’D E N G I N E E R I N G C H E J T I S T R Y
it in steam boilers, to say nothing of losses in steam lines and condenser auxiliaries. Let us see what we may do with a ton of coal. First we may coke it in a bee-hive oven and get in return 65 per cent or 1300 lbs. of coke with which we may produce something less than 1200 pounds of pig iron. Again, let us put it in a by-product coke oven. We get inreturn 1500 lb. of coke which will produce over 1350 lbs. of pig iron, about 17 c. worth of tar, 60 c. (net) worth of ammonium sulfate and still have sufficient surplus gas to replace 286 pounds of coal in the open hearth furnace or under boilers, or produce 224 electrical horse power. I n other worlds, our saving by the by-product ovens over the bee-hive is zoo lbs. of coke, 77 c. worth of tar and ammonia and 2 2 4 electrical horse power. As mentioned before, i t is very important to have the best possible heat distribution on the oven in order to get the most by-products in the gas as well as the best coke, and we wish to explain to you a coke oven which has all the features required to obtain this even distribution of the heat. This is the Koppers Regenerative Coke and Gas Oven. A battery of Koppers regenerative cokeovens (Fig. “A”) consists of a series of oven chambers placed side by side. The wall between two ovens serves as a heating wall. This heating wall consists of about 28 to 30 vertical flues in which the combustion takes place Underneath these vertical flues is a gas distributing flue. Every vertical flue is connected to this gas flue by a gas nozzle through which the gas is introduced into the vertical flues for combustion. These nozzles are interchangeable, so that a nozzle with any desired size of opening can be used Directly underneath each oven chamber is a regenerator where the air used for combustion in the vertical flues is preheated. I t enters the regenerators a t the bottom and passes up through the hot checker work and then to each individual flue, where the combustion of the gas takes place. The amount of air admitted to the regenerator can be regulated by means of individual dampers for each oven. During one period the gas burns in one-half of the vertical flues of the oven walls and the products of combustion pass into a horizontal flue which is placed just above the vertical flues and from there to the other half of the vertical flues of the oven walls, then down to the regenerator on the other side, where it gives off its heat to the checker brick and passes into a common flue leading to the chimney. The draft in each regenerator can be regulated by means of a damper a t the entrance to the regeneratorsand in eachvertical flue by sliding bricks which are placed a t the outlet of each vertical flue just where they connect to the horizontal flue. With these sliding bricks, the combustion in each vertical flue as ne11 as the length of the flame and the draft in each individual flue can be regulated. The setting of these sliding bricks can be regulated through openings from the top of the battery which means that each individual flue can be easily inspected. hfter the gas is burned on one side for a period of one-half an hour, Lhis process is reversed and the gas is burned in the vertical flues through which the waste gases passed.beforc reversing. Reversing of gas and air is done automatically by means of cables which are connected to the covers of the individual flue boxes on each regenerator as wdl to the gas cocks in the connections leading to the gas distribliting flue underneath the vertical flues. It is easily seen that with this design of oven absolutely uniform heats can be maintained over the entire oven wall, for the operator is able to inspect every part of the oven wall and regulate the combustion accordingly. The amount of gas uscd to coke a coal in these ovens amounts to but 45 or 50 per cent of the gas produced, afigurewhichis not reached by any other coke oven construction. The remaining j o to j 5 per cent of the gas produced
49s
from these ovens is received in form of gas and not in form of waste heat, as is the case in some other oven designs where the waste heat is used for raising steam- in boilers. By using waste heat for raising steam, the utilization of the B.t.u. is not as economical as when surplus gas is burned under a boiler. By using surplus gas in a boiler, one is able to regulate the amount of gas and air so as to obtain the most efficient and economic operation of the boilers. The temperature of the waste gases after they leave the regenerators on the Koppers ovens is so low that they can be discharged directly through the chimney. The advantage of the regenerators over the recuperators is well known. I n gas plants, where the main product is illuminating gas, and where there is no market for coke, the H. Koppers Co. has constructed a gas oven (Fig. “B”)which is similar to the coke oven. Instead of using half of the gas as fuel, all the gas made can be used as illuminating gas, the oven being heated with producer gas. Coke breeze and small coke from the ovens can be utilized as fuel for the producers. The regenerators on the gas ovens are divided into two parts by means of a vertical wall which extends the entire length of the oven chamber and no gas distributing flue connected to the vertical flues is used. The producer gas as well as the air necessary for combustion is preheated in these regenerators and meets in the vertical flues where combustion takes place. The amount of underfiring, that is, the amount of fuel used in the producers in order to gasify the coal in the oven chambers, is much less than that used for gasifying coal in retorts. The amount of underfiring in retorts is 16 to 20 per cent, whereas in Koppers gas ovens it amounts to I O to 1 2 per cent. The underfiring, of course, depends to some extent on the kind and efficiencies of the producers installed. The Koppers Co. has also constructed a combination oven (Fig. “C”) which can be used either as a coke oven heated with gas produced in the ovens, or as a gas oven heated with gas generated in gas producers. This oven is similar to the gas oven just described with the addition of the gas distributing flue underneath the vertical flues as on coke ovens. When operating on producer gas, the gas is sent through half the regenerators before entering th ’ vertical flues, which allows the use of all the gas produced in the ovens for illuminating gas. If only half the amount of illuminating gas is desired, this oven can be heated with a separated fuel gas, passing this fuel gas to the gas distributing flue, ihe air being preheated in all the regenerators. This oven is one of the most flexible ovens ever constructed. A plant having these combination ovens can be first operated as a coke plant by separating half of the gas and using the other half as fuel gas. The plpnt can be btiilt large enough to operate on a long coking time arid with the increase of illuminating gas consumption, the coking time can be lowered gradually so as to produce more gas corresponding to the amount of illuminating gas desired. After the limit of the coking time is reached, then gas producers can be installed and the oven heated with producer gas made from coke breeze. This allows all the gas made in the oven to be used as illuminating gas, and the coking time can be increased again. With the increasing demand for illuminating gas the coking time can be then decreased until the limit of coking time is again reached. A further increase on the demand of illuminating gas naturally would mean building additional ovens. 1307 5fALLERS BLDG CHICAGO,ILL
SYNTHESIS O F PRECIOUS STONES’ By I. H. LEVIS
Our present success in reproducing the precious stones makes 1 Presented a t the meeting of the New York Section of the American Chemical Society, May 24. 1912.
496
T H E J O URiVAL OF I X D USTRIAL AL\’D
us reflect upon the unsuccessful attempts of the alchemists to produce the precious metals. How much our modern ways differ from theirs! The so-called magic and mysticism of the alchemists have given way to science. Selfish competition and lack of cooperation have given way to accumulation of knowledge and experience and the free exchange of information among contemporaries. Desire simply to get a product has given way to real search for knowledge and the discovery of laws and principles. The solitary lives and the cherished secrets of the alchemists have made way for the free and open world-wide movements and interchange of ideas that have made our times such a n age of industry, and to take one example from out of the many, have made it possible for a contemporary, or a follower, to crown with success the efforts of groups of men that hav‘e labored to reproduce the precious stones. Of the precious stones, the diamond, the emerald, the ruby, and the sapphire have all been successfully synthesized. Only the ruby and the sapphire, however, have outgrown the laboratory stage of production, and are fast becoming important members of the field of chemical industry. The less precious stones, amethysts, garnets, tourmalines, etc., have not appealed to the chemists because they are not valuable enough as natural products. The pearl, though a true precious stone, is almost altogether of animal origin. Only the diamond, the emerald, the ruby, and the sapphire will be considered in this paper. I t will be helpful to consider the characteristics common to all the precious stones before tracing the development of the production of these stones through their checkered careers. The precious stones owe their value mostly to the permanence of their beauty. The beauty is due to their intrinsic composition and to the way the stones are made to affect light by being cut in certain forms. The permanence is due to their hardness and to the fact that the stones are chemically inert and resist corrosion. To be sure, extraneous conditions, such as custom and rareness, may affect their value. In the case of the gray diamond of Africa, the bort, and the hardest known diamond, the black diamond of Brazil, the carbonado, we have the only instance of the precious stones being very valuable when not beautiful. Color, whenever found in the gems, is due to impurities which are usually minute quantities of the metallic oxides. Various colors in the different precious stones can be produced by the same oxide, and the same color in the different precious stones has been traced to different oxides. The precious stones are transparent crystalline varieties of very common minerals. The diamond may be considered as the chef d’oeuvre of the earth’s work on carbon. The ruby and the sapphire are part of the large family, corundum, of which the ordinary emery stone is a very humble relation. Stones identical in composition with the emerald are so common at Limoges that the mineral is said to be used as paving blocks. Each of the precious stones may be made to lose some or all of its characteristics-its color, crystalline structure, transparency, and even hardness-and be made to return to common clay, so to speak. On the other hand, the “common clay” may be reacted upon in such ways that it may take on all the properties of the precious stones. Research along the lines of the precious stones has been most profitable when emphasis was placed on experiments that would lay bare the conditions that are necessary to produce the stones rather than on those which would merely bring about products. In the case of the diamond and the emerald these conditions are not known; in the case of the ruby and the sapphire they are so well understood that the making of these has now formed part of the ever-growing field of chemical industry. THE DIAMOND
The transformationfof diamond to graphite or carbon has
EIVGINEERING C H E M I S T R Y
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been accomplished again and again. The process has also been reversed and some few diamonds have been produced by various investigators. Nevertheless, no interpretation of the phenomena has, as yet, been given. The work of Moissan’ is extremely interesting, but not enlightening. H e obtained his clue from the analytical work of FriedeL2 The Devil’s Canyon was once littered with meteorites. Some of these found their way over to France and when analyzed by Friedel tiny diamonds were found imbedded in the mass of
FIG. I-ACTUAL OPERATION O F ELECTRIC FURHACE AS USED BY MOISSAN
iron. Moissan tried to reproduce the conditions of the fiery meteor. In an electric furnace he placed a carbon crucible containing pure iron and very pure carbon. The carbon dissolved in the molten iron until a saturated solution was formed, and while the material was at white heat he plunged it in a bath of molten lead or mercury. The sudden cooling caused tremendous internal pressure and the liquid carbon was crystallized into diamonds. The products were microscopic, but were hard, showed the crystalline form, and on chemical test proved to be diamonds. One little fellow weighing about 6 mg , when burned in oxygen produced about 2 3 mg. of carbon dioxide. Theoretically, 2 2 mg. should have been produced. The high dispersion of light-which is twice as great as that of glass-gives to the diamond its so-called “play of fire.” In addition to this property the diamond reflects almost all the rays of light that strike its surface and give it the characteristic luster known as adamantine. To these properties, accentuated by the lapidary’s art, the diamond owes its beauty. The chemical inertness of the gem has made it possible for the stone to conserve its beauty through the ages. The diamond, most valuable when colorless, is found, however, in very many colors. THE EMBRALD
Chemically, the emerald is a metasilicate of aluminum and glucmum, A12G13(Si03)o.Hautefeuille and Perry,* 1890, dissolved the constituents of the gem in their relative proportions in a bath of dimolybdate of lithium and keeping the bath a t 8ooo C. for fifteen days, succeeded in crystallizing out tiny emerald crystals -4little chromic oxide was used to give the green color These crystals are in every way perfect, but too small, the largest being only z mm long by I mm. wide and I mm thick They were very expensive, much more so than the earth-made product. Beyond this successful laboratory attempt, no one has, up to the time of this writing, made public the making of, if made a t See Comb:. r e n d , 1892, 1893, 1894, 189.5, 1896 (le four 6lectnque). Friedel, “Sur l’exlstence du diamant dans le fer meteorlque du Canon Diabolo,” Comples rendues de 1 Academze des Sczences, 114, 1037, Dec 12, 1892 3 Annales de chrmte et de physcque. 1890, 6 sene, tome XX,pages 447, etc. 1
2
June, 1913
T H E JOCR-\-AL OF I,\’DUSTRIAL
all, the emerald on a n industrial scale. The experiment of Hautefeuille and Perry, though extremely interesting, is not very iastructive, and, as 17-ith the diamond, we are not much nearer to knox ing what are the conditions necessary to be attained to make the emerald The emerald owes its value to its green color and resembles the color of the grass in the spring The common beryl is a golden yellow. The emerald is identical n i t h it in every respect, save color This difference is due simply to the presence of different impurities. Almost all the rays of light impinging upon the surface of an emerald enter it, and very few are reflected from its surface, very much as in the case of glass. Furthermore, the emerald is not as optically dense as the diamond. We have, therefore, neither the metallic luster nor the “play of fire” as in the diamond. However, there resides in the emerald a rich, soft, green color that gives to the stone a charm that is to some much more fascinating than the brilliancy of the diamond. THE R U B Y
The ruby was the first of the precious stones to be synthesized on a commercial scale and has a more fascinating history than either the emerald or the diamond Chemically speaking, it is simply the oxide of aluminum with a trace of chromic oxide, to Tyhich it owes its rich pigeon blood color. The natural product has traces of othcr impurities that play a r6le that seems to us, in our present lack of knowledge, to be far out of proportion to their actual size The synthetic product is ofttimes ruined in the making by quantities of impurities that are so small t h a t they can scarcely be detected by analytical methods. Corundum is often free from the oxide of chromium and we have either a colorless stone, or, if some other oxides sapphire-or are present, we may have a blue stone-the shades of green, yellow, smoky tinges, etc. As a n example of the traces of impurities in the natural product, note the effect of radium emanations on some of the earth-made rubies, sapphires, and colorless corundum, and the non-effect of the emanations on the synthetic rubies and colorless corundum. (The effect of radium on the synthetic sapphires has not yet been ascertained j F. Bordas using radium bromide of 1,800,oooactivity turned rubies into brick-red color, white into brown and black, and blue stones into greenish to yellowish tinged stones. The synthetic stories nere not affected. These very same transformations ha>e been produced by the writer in the case of some synthetic rubies and colorless corundums by the admixture of a trace of the same impurity in each of the stones. (The influence of this material plays so great a part in the industry that I hope the non-mention of same will be excused.) Crystalline transparent alumina can be crystallized out of molten baths, can be condensed as crystals from its gaseous state, and can be “frozen” into crystals from the molten state. The most interesting attempt to crystallize alumina out of molten baths was that of F r h y and Hautefeuille. The oxides of lead, aluminum, and chromium were fused in a large crucible for about seven to eight days in a furnace used for glass-making. Masses of rubies from 30 to 40 kilos v e r e sometimes obtained, but among these not a ruby was found that was thick enough to be of any value as a gem. One of the crystallographic axes developed more than another, and only thin, laminated crystals were produced. The attempts to condense the alumina vapor produced similar useless crystals, judged from the view point of gems. About this time we have a new generation interesting itself in the same problem. Fremy worked with a number of colThey found that alumina and laborators, during 1877-1890 hydrofluoric acid, on being heated, would cause the aluminum fluoride formed to be reacted upon by the water vapor produced
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49 7
and condense as corundum. As they were originally w i t t e n , we have A1,0, -!- 6 H F = zAlF, t- 3H,O gH,O = A1,0, t- 6 H F ZAlF, At that time there was only a suspicion that there were such phenomena as chemical equilibria (writing the previous reaction thus: 6HF A1,0, zAlF, -t 3H,O the reversibility of the reaction and the existence of the equilibrium is easily noticed). But the platinum ware to carry out the above was too costly, and FrGmy and Feil, and latter F r h y and Verneuil, carried on a series of brilliant experiments with ordinary sand crucibles. I t was found that in the presence of vapor of K,CO, amorphous alumina would be changed into corundum. Sand crucibles were filled in the following manner: Alumina, K,CO,, and Cr,O, were mixed with fine charcoal, which mas packed around a core composed of alumina and Cap. Upon gently heating, the charcoal escaped as CO, and made the mass porous. Each tiny hole became a nest, as it were, where a tiny ruby was born. The slower the process, the larger the rubies that were produced. Carrying on the process in only eight days the largest stone produced was 4 to 5 mm. long and about FIG. 11-ARRANGEXENT O F CRUCIBLE1s THE EXPERII mm. thick, weighingabout one-third carat, or 60 mg. To produce larger .\IENTS OF FRBMY AND COLLABORATORS stones the process would have to be carried on infinitely slower. If the assumption be correct that a large stone could thus be made, the product would be, of course, very interesting, but the process much too costly. Thus the corundum crystallized out of molten baths or condensed from vapors produced only thin, lamina1 crystals. These not only mere too thin to be cut into gems, but lacked the beauty of the earth-mhde product which appears to be made up of a series of layers. The light coming through these layers enriches itself and gives to the ruby its wealth of color, Rubies are made to-day by fusing alumina in the oxyhydrogen flame and permitting the molten mass to solidify in the cooler zones of the flame. With the introduction of the oxyhydrogen torch of St. Clair Deville, experiments mere begun. Here, again, Gaudin turned his attention to the synthesis of the ruby. H e succeeded in fusing quartz which has a melting point slightly higher than corundum with the oxy-hydrogen flame. H e tried for thirty years to fuse alumina into corundum but without success. So long as the material mas in the flame it was transparent, but the alumina cooled into opaque masses when the flame was removed. Gaudin’ in his last memoire concluded that it was impossible for him to produce transparent corundum by using only alumina because of the great tendency of the substance to devitrify (become opaque). Moreover, alumina melts a t a very high temperature without passing through a pasty state. I t suddenly becomes fluid like water and then vaporizes and rapidly disappears like camphor. The matter was given up for about fifteen years; for there was little hope proffered for its fulfillment. I t then happened that rubies appeared on the market whose origin could not be accounted for. It was explained that a mine was discovered near Geneva. As a matter of fact, a curate, or priest, succeeded in fusing chips of natural rubies given him by the lapidaries of Geneva, into large stones. If ruby chips could be fused, then A1,0, could. This latter, Vcrneuil* succeeded in accomplishing after many years of labor, ,and developed the process so that
+
+
Comfit. rend., 69, 1343.
__
* Annales de chimie et de physique, 8 , serie I1 ( 1 8 9 4 ) .
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THE JOURiYAL OF I N D U S T R I A L AA'D ELVGINEERING CHEMISTRY
Val. 5 , NO. 6
the oxygen, extends about a foot beyond the outer and has a cylindrical shaped top. I n the lower portion of the torch, the outer or hydrogen carrying tube extends a n inch or kwo beyond the oxygen tube. The ruby forming powder is placed in a sieve bottom box which, in turn, is screwed into the cylindrical top of the oxygen tube. When the torch is lit, a little hammer is caused to knock periodically on the top of this box, and particles of alumina are
FIG.IV-DIFFERENT PHASESIN THE MAKING O F THE RUBY A=CONE O F A1203 SIMPLY FRITTED C=ENLARGED ROWLE B = FORMATION OF PIN HEAD D =STILLLARGER BOULE
thus blown into the flame. I n the beginning of the process, the flame is comparatively cold and just heats a n earthenware rod that is so placed as to catch this powder. As the powder continues to fall on this rod it forms a pyramid of fritted alumina. The heat is gradually increased until the top of this pyramid becomes molten and a tiny stalk, so called pin-head, begins to grow. At this stage the flame is made still hotter a n d the powder falls in molten drops upon this pin-head. Each succeeding drop falls upon a larger base until a n unflawed pear shape, or so-called ruby boule, is produced. This boule is one single crystal with the optical axes directly perpendicular to one another. When the stem of this boule is broken the stone breaks in two. The great difficulties encountered by Prof. Verneuil in his early attempts were because of this peculiar nature of the stone. Accidentally hc obtained a small boule formed on a long, straight stem, and for many years FIG. 111-AN EARLY TORCH OF PROF.TERNEVIL FOR THE SYNTHETIC afterward failed to reproduce the same result. The rubies that PRODUCTION O F THE RUBY he tried to make were all formed on a very wide base, and upon cooling broke into tiny particles. rubies could be made that were large in size, good in color, and Pure alumina is one essential of this process. The presence at sufficient speed to make the industry possible. of O.ooo5 of I per cent. of a certain impurity is sufficient to A modified inverted oxy-hq-drogen torch of Deville is used absolutely discolor the ruby, and produce a brick-red instead as the starting point in modern practice. I t produces a flame
FIG.V.-MAKINGSYNTHETIC STONES AT
of many zones varying in temperature from igoo0 to 2400~C. The torch consists of two concentric tubes: the inner tube carries
THE
PLANT O F L. HELLER & SON,PARIS
of the pigeon-blood stone. I n our making of alumii; . a very interesting state of equilibrium occurs, the ignorance of whose
June, 1913
TIT& JOr..R,\rAIL
O F I . V ~ l ~ ~ . S T i ~ l I:'. A"IJ,l l %.\~Gl.YEEEK I .YG ( : I I E X ISTR Y
prcsence caused a loss for a short time of about 16per cent of thc product. There are many technical details coniiected with the getting of pure alumina. Sufice it to say that thc rnatcrial must bc extremcly pure, for every impurity has a tendency to ruin the product by cither spoiling the color or making tlic ma^ tcrial britt!?. The delicacy of the entire process may be inferred from tlir aborc. T h r slnrie cut from a boule is in every xay similar to thc natural ruby. Physically and chemically thes- stones are
Pro. VI-VIBW IN FLAW* ow L. N E L L B R & 60s
499
pcrature, and pressure that the earth might h a w cmployed, ,,-as, of coiirse, an enigma, so that the view point taken to correlate thc gem with the products lliat might be made in the laboratory mias that the sapphire was simply an earth-made bcad, blue in color, ctc. Although the melting point, about 1870' C., and boiling point of corundum are quite close, still, by Verneuil's method of fusion, s m w phenomena of corundum solutions may be &served and intrqxctcd. In this way the
research was brought in line with past chemical experiences with the result that many reactions could bc predicted. The production of blue articles in ceramics. or other fused products of industry, or the OCCUII~IICC of b!uC in the fusion of any of the alumina materials, such as bauxite, or any high temperature reaction which produced bluish colored products, especially those in which the oxides of interest played a part, were carefully investigated. In this way the research was further correlated with past chemical experiences. Some of the nemtive rcsults following the various clues WTC,
identical. There is perhaps but one method of telling the synthetic from the natural stone, and that is that in the natural stones the imperfections have flat bounding sides and w e socalled negative crystals; the imperfections in the synthetic stones have round surlaces and are simply air bubbles which in many cases can be detccted only by a.powerful magnifying glass. Both the natural and the synthetic stones arc made up of a series of successive layers. I n the case of the synthetic stone, onc can realize from the n a y it is made, the layers are curved: the natural product has flat parallel layers. TIIS SAPPBIRS
It will be remembered that the synthetic ruby industry first started with reconstructed stones. Sapphire chips, however, can not be fused into reconstructed sapphires in a similar way because the color disappears. This phenomenon was excellent material for half~bakedinterpretations with corresponding reSUltS. We took up the research on the sapphire in our laboratory in Paris in '909 with Prof. Vcrneuil as chief chemist. The sapphire owes its blue color to the presencc of minute quantities 01 the oxides of iron and titanium; however, up to the synthesis of the sapphirc, there mists no complete analysis showing borh a1 thrse oxides to be present in lhe gem. The method umployed in the rcstarch was, in brki, the making of corundum bcads or boules by means of Prof. Veriieuil's torch and method of fusion, and studying the coloringpraperties al the various oxides. The research was further correlated with the earth-made product mith past experiences in purc and applied chemistry. The view point was necessarily always taken from the only means a t hand to produce coruudum beads. The history of thr gem, such as the duration of time, tem-
nevertheless, quite interesting, but only a few can lic mentioned h e x I n the majority of cases the clucs followed gave positive results. In some of the cxpeiiments of Sainte Claire Deville and Carion' to obtain the ruby, blue patchcs were obtained, and it was believed by them that the sapphire owcd its blue color to a lower oxide of chromium. Successive experimenters. however, failed to realize any blue color by the use of some of the oxides of chromium. The cobalt oxides, which are used so extensively in ccramics to produce blue, can nul, for some icason or other, be rctained in thc corundum. l+y the addition of materials such as CaO, blw stones are ohtainrd which arc, however, not genuine, synthetic sapphires.
' ConW mzd., 66.
765 (lR58).
T H E JOURA-AL OF I l Y D U S T R I A L AND E.VGINEERIlVG C H E M I S T R Y I n Gintl’s’ work on the fusion of bauxite in the electric furnace, some blue patches of corundum were made which showed, on analysis, to consist of TiO,, 0.65; FeO, 0.79; MnO, 0.50; CaO, 1.83; MgO, 0.35; NaO, 2.07; SO,, 12.28;A1,0,, 81.88. Scoria in the blast furnaces are sometimes blue, and owe their color to the presence of titanium. Titanium, while not found in abundance in any one locality, must, nevertheless, be widely distributed for there appears to be more titanium than carbon in the earth’s crust. The titanium oxides grade away in color from the white of TiO, through blue to purple when you get to Ti,O,,. Attempts to make lower oxides with hydrogen were not successful. Ferric oxide a t 1 3 0 0 ~ C. to 1350’ C. dissociates into Fe,O,, or the lower oxide; and the oxides of iron or pure Fe or any compound of iron become FeO or, perhaps, Fe,O, when fused with corundum. The bead, or boule, is light gray to colorless. Thus iron and titanium when fused with corundum undergo oxidation and reduction. The products that were obtained by this fusion were pinkish. I n ordinary solutions, it is well known that every oxidation and reduction is accompanied by change in color. I t was this phenomenon that was taking place in the production of the pinkish color. Attempts to get the blue were accompanied with so little success that substances other than iron were used to reduce the titanium. Anatase is blue and has a small percentage of one of the oxides of tin. SnO and SnO, with TiO, showed very little tendency of reduction. The reaction between iron and titanium is very strongly reversible. By simply adding a slight excess of one of the oxides, the reaction can be made to go in the direction of reduced titanium, resulting in perfectly blue corundum boule. The ultimate production of the sapphire in the laboratory left very few technical problems unexplained. This made it possible for the manufacturing department to take up work within a week after the successful conclusion of the research. Little change has been found possible since. The corundum boule is in every respect identical with the earth-made product. Experts are much less able to tell the synthetic from the earth-made sapphire, than they are the synthetic ruby from the earth-made ruby. After fusion only part of the iron and titanium oxides are left. Prof. Moses2 found only traces of Fe,O, and about 0.1of I per cent. of TiO,. The analysis of the natural products extant before the synthesis of the sapphire did not show the presence of titanium oxide. Prof. Verneui13 has very carefully analyzed some sapphires from Australia, India and Montana that were perfectly clear under a magnifying glass with the following result in percentages: SAPPHIRE FROM AVSTRALIA Iron oxide.. , . . , , . . 0 . 9 2 Titanium. . , , . . . . , . 0 . 0 3 1 Silica... . . . . . . . . . . a trace
.
.
.
INDIA
MOKTANA
0.72 0.04
0.56 0.058 0.10
The unpolished earth-made and the synthetic ruby or sapphire is far from being a thing of beauty. I t requires the lapidary’s a r t to bring out their intrinsic qualities. The earth-made products can lend distinction to their wearers and therefore are very highly prized. The synthetic products because of their intrinsic beauty and genuine worth appeal to the many. About IO,OOO,OOO carats of rubies and about 6,000,000 carats of sapphires are produced annually and the demand is growing very rapidly. LABORATORY OF INTERNATIONAL OXYGENCOMPANY NEW YORK
Gintl, Zeitschrift fiir anoewandte Chemie. 1901, P. 1173. American Journal of Science. 30, 4th series, Oct., Compt. rend., 151, 1065, Dec. 5 . 1910.
1910.
Vol. 5 , No. 6
THE GOVERNMENTS’ INTERESTS IN THE PULP AND PAPER INDUSTRY By MARTIN L. GRIFFIK RAW MATERIAL
Book paper is almost wholly made from nood by chemical processes, resulting in recovery of only about half its solid contents in pulp. I t takes about two cords of wood for one ton of pulp and the wood alone mill cost about twenty dollars. This will average about half the total cost of producing bleached pulp a t the present time How important then is the item of wood ! Economies in the process of manufacture have been possible and necessarily effective, but nothing more can be gotten out of the mood than it contains. EARLY HISTORY O F PULP-MAKING
I n the early days of chemical wood fiber the processes were crude, labor and wood plentiful and cheap. Chemical wood pulp mills were located in such places as Philadelphia, Providence, Derby, Conn , Holyoke (two mills), Turner’s Falls. England was a pulp-producing country. These mills went out of business years ago with the receding supply of qvood. Ever since, the manufacturers of this pulp have either moved up to the supply or the supply has been brought to the mill, in most cases a t a large expense for transportation, or else manufacturers of this grade of paper have altered their plants to manufacture higher grades. PRESENT ASPECT
During the past twenty-five years the cost of wood, notably spruce, has doubled; other costs have increased, while the price of paper has remained a t a very low level. A great industry in wood papers has been developed a t a present capital investment of one hundred and twenty million dollars. Our natural resources in wood have been greatly depleted and converted into paper for the people of the United States a t a very low price. Conditions in the manufacture of this class of papers are fast becoming intolerable even with a protective tariff of $ I O 00 per ton, due solely to the vanishing point of our wood supply. The cost of transportation by rail to our mills is a great burden on our manufacturers, n hich Canadian manufacturers do not habe to bear. Once our mills received their wood supply by floating it down the rivers. Now these resources are largely gone and our Canadian neighbors occupy this point of vantage. THE STATE OF
MAINE
Maine occupies a peculiar position in this matter. Formerly, well wooded with the most desirable species for lumber and paper and traversed by more large rivers than any other state, lvhose head waters are great natural reservoirs, its people built up a great industry. It extended its railroads and enlarged its facilities to this end. All of this growth had its source in the natural resources of the state GEOGRAPHICAL LOCATION
Jlaine, situated as it is a t the extreme eastern boundary of the United States, larger in extent than all the other New England states combined, is and forever will be a t a disadvantage in doing business in our home markets. There is no possible means of offsetting this transportation handicap to our markets and sources of supply. Some other advantages must exist or else development, so slow in the past, will cease altogether and present industries, of which I a m writing, must die out. And I say, when the pulp and paper industry of Maine wanes and finally dies, as it inevitably will within the next twentyfive years if matters are allowed to take their present course, there will be no other to take its place. What motive, what 1 Paper presented before the Maine Section of the American Chemical Society, Auburn, March 19 1913
