A N D ENGI-VEERI-VG C H E M I S T R Y measured 6-7.5 liters per charge of 60 grams of sludge, or on a basis of 11.38cu. m. per r o o kg. It was collected over water and allowed to stand over night. It was then burnt in a fishtail burner and found t o give about I/, the illumination that the city gas supply gave. The flame contained a comparatively large porportion of blue. Analysis of the gas gave the following results, IOO cc. being taken for each analysis and the analyses being done in duplicate :
burnt in a fishtail burner i t gave a flame far brighter than the flame of the city gas. Analysis gave the following results, the procedure being the same as in the analysis of the gas made without the superheated which has been already described.
5'01. after K O H . . . . . . . . . . . . . . . . . 74.9 x-01. after fuming HzS04.. . . . . . . . . 70 .O Vol. after pyrogallol.. . . . . . . . . . . . 6 9 . 4 Vol. after cuprous ammonium. . . . 59 S
I O cc. of the residue was then mixed with 40 cc. of air and exploded by means of a n electric spark. Vol. before explosion. . . . . . . . 5 0 . 0 cc. ....
cc. cc. cc. cc.
7 5 , 9 cc. 2 4 . 6 R CO2 i o . 8 cc. 5 . Oyc Hydrocarbons 70.2 cc. 0 . 6y0 0 2 61.2 cc. 9 . 6 4 5 CO
cc. of the residue were then mixed with 50 cc. of air and exploded by means of an electric spark. IO
5'01. before explosion. . . . . . . . 60 cc. Vol. after explosion.. . . . . . . . . 5 1 . O cc. 5 0 . 6 cc. 9 .O cc. 9 . 4 cc. Mean, Vol. of contraction.. . . . . . . . . 1'01. after KOH.. . . . . . . . . . . . 4 8 . 6 cc. 4 8 . 8 cc. V O l . of coz. . . . 2 . 4 cc. 1.8 cc. JIean, Vol. of CH4, in 10 ue... . . . . . . . . . . . . . . . . . . . . . . Contraction due t o Hz 0 2 in 10 cc. residue.. . . . . . . . . Vol. of Hz in 10 cc. residue.. . . . . . . . . . . . . . . . . . . . . . . . . Results for CH4, Hz and NZon basis of original gas: Vol. of H z . . . . . . . . . . . . . . 1s . 8 per cent. Vol. of CH4.. . . . . . . . . . . . 13.0 per cent. Vol. of K2,. . . . . . . . . . . . . 2 7 . 8 per cent. (by difference)
.....
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9 . 2 cc. 2 . 3 cc. 2 . 3 cc. 4 . 6 cc. 3 . 1 cc.
The density of the gas was found by Bunsen's diffusion method, as follows: average time for series of experiments
.......
Air. 2 6 , 85 seconds 22.99 seconds Sewage gas City g a s . , . . . . . . . . . . . . . 18.52 seconds
Results 1.000 sp. gr. 0 733 sp. gr. 0 468 sp. gr.
I'n order t o decompose the basic tarry distillate into more useful compounds, in the next series of experiments, the products of distillation were passed through a coil of inch gas pipe heated to bright redness. The coil was about I O cm. in diameter and contained about 2 . 5 m. of pipe. I t was expected that this would give a larger yield of gaseous products, and a t the same time cause the decomposition of many of the complex organic bases into ammonia. Simultaneously the more valuable hydrocarbons of the benzol series ought t o replace them in the tar. The only alteration, therefore, in the apparatus for this series of experiments, was the insertion of the superheating coil between the retort and the condenser. The procedure in the experiments remained the same as in the first series. Under these conditions, the liquid distillate, Tvhich in the first series had the odor of pyridine and its homologues, now had the black color and characteristic odor of common coal tar. Theamount, however, was less, the yield from 60 grams of sludge being on a n average 8 grams. An aliquot part of the gas liquor was taken for the determination of ammonia, the gas being distilled off and titrated with standard acid. The yield was found t o be on a basis of 0 . 2 7 kg. A-H3 per I O O kg. sludge. The gas, as produced from the apparatus with the use of the superheater, was increased in quantity and improved in quality. A charge of 60 grams of sludge gave on a n average 11.4-11.9liters of gas, or on a basis of 19.08 cu. m. per 1 0 0 kg. sludge. When
Val. after K O H . . . . . . . . . . . . . . . . . 8 1 . 2 cc. 8 2 . 0 cc. lS.470 COz Vol. after fuming H?S04.. . . . . . . . . 65 .2 cc. 66.2 cc. 15.97c Hydrocarbons 5'01. after pyrogallol.. . . . . . . . . . . . 64.5 cc. 65.4 cc. 0 . 7Yc Oa Val. after cuprous ammonium..
Vol. 1'01. 5'01. Vol.
..
5 6 . 6 cc. 5 8 . 4 cc.
after explosion., . . . . . . . . 3 7 . 2 cc. of contraction.. . . . . . . . . 12 .S cc. after KOH.. . . . . . . . . . . . 3 4 . 8 cc. of COa.. . . . . . . . . . . . . . . . 2 . 4 cc.
7
3 8 . 4 cc. 1 1 . 6 cc. 36 . O cc. 2 . 4 cc.
CO
>lean, 1 2 . 2 cc.
X'ol. of CHI in 10 cc. of residue.. . . . . . . . 2 . 4 cc. Contraction due t o Hz 02.. ......... 7 . 4 cc. Vol. of H:! in 10 c c . , . . . . . . . . . . . . . . . . . 4 , 9 cc. Total vol. of CHI in original gas.. ...... 13.8 cc. Total vel. of H2 in original gas. . . . . . . . . 28.2 cc. Total vol. r\r2 in original gas. . . . . . . . . . . 15.5 cc. ( h y difference'
+
The density of the gas was found by Bunsen's diffusion method, as follo\vs: Average time for series of experinients Air., . . . . . . . . . . . . . . . . . 22.20 seconds G a s . . . . . . . . . . . . . . . 20.06 seconds
Results 1.000 sp. gr. 0.499 sp. gr.
S L-11XI A R Y
We can briefly recapitulate the results obtained in this work as follows: I . That the sludge will become almost dry a t ordinary temperatures in four days, or in less than ten hours if exposed t o a mild, artificial heat. 2 . That the yield of gas from the heated sludge is comparable to the yield from a ton of gas coal, if the products of distillation are passed through a superheater. 3. That the quantity of illuminating hydrocarbons in this gas is almost three times as great as in coal gas. 4. That the superheating of the tarry distillate changes its character from a substance resembling bone oil to what appears to be coal tar. 5 . That the amount of ammonia is fully equal to that obtained from coal. CHEMICALLABORATORY, HARVARD COLLEGE CAMBRIDGE, MASS.
ALLOYS O F COBALT W I T H CHROMIUMAND OTHER METALS' B y ELWOODHAYNES
As in organic nature, certain animal and vegetable forms have undergone modifications, and thus, as i t were, fitted themselves to live in a new environment. so i t has been found possible in certain instances to form new metallic combinations which are practically immune to the natural conditions that exist on the earth at the present time. A few of the rare metals, such as gold, silver, and the metals of the platinum group, are found native, but the commoner heavy metals are nearly always found in the form of oxides or sulfides. For a number of years I have made experiments with a view t o finding certain metallic combinations Paper presented a t the Eighth International Congress of Applied Chemistry, New York. September, 1912.
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THE JOUR,VAL OF I,VDUSTRIAL A,VD E.\'GI.VEERIA1-G
or alloys which would not only resist oxidation and other harmful influences, but would also possess valuable physical properties, which would render them fit for special services. The first decisive step made in this direction, mas the discovery of a n alloy of nickel and chromium in 1898. The properties of this alloy have already been described in a previous paper.' Immediately following the discovery of the nickelchromium alloy, I produced a n alloy of cobalt and chromium. This has likewise been described in the previous paper, but the range of proportion between the cobalt and chromium is so great, and the combination is modified to such a marked degree by the introduction of other substances, that I have felt justified in reading another paper on this subject, describing more fully my researches in this particular direction. As early as 1907 and 1908,I made alloys or combinations of cobalt, chromium and tungsten; cobalt, chromium and molybdenum ; and cobalt, chromium, tungsten and molybdenum. I have made alloys of cobalt and chromium containing zirconium, tantalum, thorium, titanium, vanadium, etc. I have also added t o the cobalt-chromium alloys the non-metallic elements, carbon, silicon, and boron. Some exceedingly interesting results have been obtained from these various combinations, and while further investigation is necessary in order t o fully determine their chemical and physical properties, a number of them have shown interesting economic possibilities. The preliminary fusions were made in graphite crucibles by means of a furnace operated by natural gas. I was later obliged to use crucibles of a special composition, not only to avoid the contamination of the metal by carbon from the crucible, but also because they proved more reliable under long-continued heating, than those made of graphite. The metal tungsten alloys readily with chromium and cobalt in all proportions. When added in small quantity to the cobalt-chromium alloy, i t seems to have little influence on the properties of the combinations, but if the proportion rises t o 2 per cent. or 3 per cent., a notable effect is produced. Generally speaking, the cobalt-chromium alloy becomes harder and more elastic, especially if it contains a small amount of carbon, boron, or silicon. The following experiment shows the effect of melting the alloy in a graphite crucible: y o grams of cobalt, 6.3 grams of tungsten, 18 grams of chromium, together with a small quantity of calcium silicide, were introduced into a graphite crucible. The resulting alloy was very hard, and the ciucible much eroded on the inside. The bar could be slightly flattened a t one end, and after being made into a cold chisel, showed remarkable qualities. It would not only scratch glass, but also quartz crystal. I t was quite tough a t ordinary temperatures, and would cut small chips or shavings from a piece of stellite. At a bright yellow heat i t showed signs of fusion, and became covered with a skin of oxide. An alloy was made by melting the following in a 1
THISJOURSAL, 2, 397.
CHEMISTRY
Mar., 1913
special crucible : Cobalt rondelles 80 grams, chromium 20 grams, tungsten 7 grams, calcium silicide I O grams, calcium carbide j grams. As soon as the above were melted, the crucible cover was removed, and I j grams of a n alloy of cobalt and boron were introduced. The crucible lid was then replaced and the heating continued. A heavy, thick slag formed, which was removed before pouring the metal. The resulting bar was very hard and elastic, but drew only slightly under the hammer, and then broke. A cold chisel made from the cast metal cut iron readily. The bar was broken up and remelted with about one-third of its weight of an alloy of cobalt, chromium, tungsten and carbon. The result was a fine-grained alloy which was very elastic, and would draw out t o a considerable degree under the hammer without checking. Its elastic limit must have been very high, since when i t broke, the pieces were thrown violently. Taking the alloy of chromium and cobalt as a basis, and holding the proportion of chromium a t 1 5 per cent. of the entire mixture, i t was found that the alloy gradually increased in hardness with the percentage of tungsten. When the quantity of tungsten rises t o j per cent., the alloy becomes distinctly harder, particularly when forged under the hammer. When the tungsten reaches I O per cent., the metal still forges readily, and a tool formed from the alloy takes a fine cutting edge. This alloy is suitable for both cold chisels and wood-working tools. When the tungsten rises to 15 per cent., the metal can still be forged, but great care is necessary in order t o avoid checking. This alloy is considerably harder than that containing I O per cent. of tungsten and is excellent for cold chisels. When the tungsten rises t o 2 0 per cent., the alloy is still harder, and can be forged to a small extent. It makes good lathe tools for cutting steel and other metals a t moderate speeds. When the tungsten rises t o 2 5 per cent., a very hard alloy results, which cannot be forged to any extent, but casts readily into bars which may be ground to a suitable form for lathe tools. These tools have shown great capabilities, particularly for the turning of steel, since they are very strong, and retain their hardness a t speeds which almost instantly destroy the cutting edge of a steel tool. The tungsten may be still further increased to 40 per cent., and the alloy will retain its cutting qualities, and for turning cast iron, this alloy answers even better than that containing 2 5 per cent. When the tungsten reaches 40 per cent. or more, the alloy becomes so hard that i t will not only scratch glass, but will readjly scratch quartz crystal. A small drill, made of this material, drilled a hole through the wall of a glass bottle without the addition of any liquid or other lubricant. A three-eighth inch square cast bar, when ground to a suitable edge, was set in a tool holder attached to a lathe. The workman who had operated the lathe, had been able to turn to form 2 6 cast iron wheels in I O hours with a steel tool of the same size. The stellite tool turned 49 of these wheels t o form in the same time. The steel tool was ground 50 times during the operation, while the edge of the stellite tool was dressed slightly by a carborundum whetstone, after its day's work was
Mar., 1913
T H E JOI;RAY.4L OF I A V D U S T R I A 4 LA S D E-YGI.4-EERI-YG C H E - I I I S T R Y
completed. A set of steel cutters, placed in the boring head of a cylinder-boring machine, were able t o bore from 26 t o 28 holes in I O hours. These cutters were replaced by others made of stellite. which performed the work in 3 hours and 2 0 minutes, or a little more than one-third the time. Not only was the speed of the mill doubled, but the feed also, and notwithstanding this severe ordeal, the stellite cutters were only slightly worn, while i t would have been necessary t o regrind the steel cutters at least two or three times for the same service a t slower speed. Some remarkable results were obtained in the turning of steel on the lathe. For example, a cylindrical bar of annealed nickel-chrome steel, about two and one-half inches in diameter, was placed in a lathe and turned with a steel tool a t about as high a speed as the steel would permit without “burning.” The steel tool was then replaced b y one of stellite, and the speed a t the same time increased to two and two-thirds its former speed. The stellite tool retained its edge under these severe conditions, and produced a shaving weighing one and two-tenths pounds in one-half minute. Just what the effect of the alloy will be in machine shop practice is a t present somewhat difficult t o determine. In my opinion, however, it will not fully supersede highspeed steel in the machine shop, but in cases where rapid work is’the main consideration, it will doubtless replace high-speed steel. When molybdenum is added t o a 1 5 per cent. cobaltchromium alloy, the alloy rapidly hardens a s t h e molybdenum content increases, until the content of the latter metal reaches 40 per cent., when the alloy becomes exceedingly hard and brittle. It cuts keenly and deeply into glass, and scratches quartz crystal with ease. It takes a magnificent polish, which it retains under all conditions. and on account of its extreme hardness, its surface is not readily scratched. When 2 j per cent. molybdenum is added t o a 1 5 per cent. chromium alloy, a fine-grained metal results, which scratches glass rather readily, and takes a strong, keen edge. I t s color and luster are magnificent, and i t will c;oubtless find a wide application for fine, hard cutlery I t cannot be forged, but casts readily, and its melting point is not abnormally high. If carbon, boron, or silicon be added t o any of the above alloys, they are rendered much harder, though their effect is not always desirable, since they tend to render the alloys more brittle. If either tungsten or molybdenum is added to a cobalt-chromium alloy containing 2 5 per cent. of the latter metal, the hardness of the alloy is rapidly increased. When the percentage of tungsten, for example, reaches 5 per cent., the alloy can be readily forged, and forms a n excellent combination for woodcutting tools, such as chisels, pocket knives, etc. When molybdenum is added t o the same mixture of chromium and cobalt, much the same effect is produced, though, generally speaking, a smaller quantity of molybdenum is required t o produce a given increase in hardness. I n some instances I have found i t advisable t o add both molybdenum and tungsten t o the cobalt-chromium alloys. Generally, the color and
191
luster of these alloys, after polishing, are magnificent, and they seem t o resist atmospheric influences equally as well as the binary alloy of cobalt and chromium. KOKOMO, ISDIANA
T H E RELATION O F T H E PRODUCTION O F ALUMINA TO T H E FIXATION OF NITROGEN’ B y SAMUEL A . TCCKER
The connection of nitrogen fixation and the production of alumina is t o be found in the Serpek process and probably in this process only. The Serpek process is primarily one for the fixation of nitrogen, but necessarily involves the production of alumina as a by-product and this by-product is all important to the success of the process commercially. Briefly the Serpek process takes alumina and carbon in the proportions t o form aluminium nitride in a strongly heated atmosphere of nitrogen, or A1,0, 3C 3 , + 2A1N $0. The range of temperature necessary for this reaction is from 1600~--2000~ C . according t o Serpek. The product obtained contains about 30 per cent. nitrogen in the form of aluminum nitride, and is thus considerably richer in fixed nitrogen than calcium cyanamid which rarely runs over 2 0 per cent. This reaction appeared so important to me that I thought i t was worth while to investigate i t and in conjunction with Mr. H . L. Read, the process was tried on a small scale. The results of this work have been read a t the recent Congress of Applied Chemistry,” and i t will be unnecessary $0 repeat them here, excepting t h a t we found t h a t the reaction worked satisfactorily on a small scale, the product contained 30 per cent. of nitrogen, and t h a t bauxite was the best material with which to supply the aluminium. The temperature is important; below 1600’ C. practically no nitrogen is fixed; above z o o o o C. decomposition is likely to occur. I would like t o know more as t o the influence of temperature, and I had expected t o conduct some experiments on this point so t h a t I might give you this information now, but a n accident t o the electric furnace prevented i t . The commercial product must be nearly pure aluminium nitride, and a t first sight seems t o consist of two forms, the blue and the yellow. Professor Luquer has examined these specimens microscopically, and while his examination has not yet been completed he tells me that the internal structure is the same: both are strong double refracting and show uni-axial structure. With our present information, it would be difficult t o figure the cost of production of this material, and even the power necessary for its manufacture is probably not generally known. The question of the necessary time t o convert t h e charge is important and in our experiments we found that i t had a great influence on the nitrogen content of the product. I t therefore seems necessary t h a t
+
+
+
1 Presented a t the Joint meeting of American Electrochemical Society, Society of Chemical Industry and American Chemical Society, Chemists’ Club, New York City, F e b r u a n i, 1913. 2 See also .Vel. Chem. E?tg., 9, 7 4 5 .
