Sulfur. I - ACS Publications

San Angelo, Texas. “^^ULFUR is a fatty earth thickened in the mine by boiling until it has hardened and become dry; and when it has hardened it is c...
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SULFUR. I WILLIAM A. CUNNINGHAM, Chemical Engineer San Angelo, Texas

average man of 2000 years ago. He looks upon sulfur as a yellow powder to be readily obtained from the corner drug store; he knows that when it is burned there is produced an "evil-smelling" gas; he knows that it is useful as an insecticide when dusted on his rose bushes; he frequently bums it in the sick room as a none-too-effective fumigant; and sometimes he remembers that it is one of the essential plant foods. But the chances are that he does not know how sulfur is mined or that Texas produces annually about 2,500,000 tons of sulfur valued a t $45,000,000 and that this is approximately 85% of the world's sulfur production and over 95% of the United States sulfur production. The amount of sulfur in the earth's crust is estimated to be about one-tenth of one per cent. It occurs in a variety of mineral forms; those minerals of commercial importance are the sulfates, the sulfides or pyrites, and native or free sulfur. Of the sulfate minerals, the most abundant is the sulfate of calcium, commonly known as gypsum. As yet the sulfates are not important as a source of sulfur. A process has been patented by which calcium sulfate may be used as a raw material for the manufacture of portland cement, with a view to reclaiming the sulfur dioxide produced in the clinkering process for the manufacture of sulfuric acid. This process, however, has never been developed on a commercial scale. The sulfides of copper, lead, zinc, and iron were for many years a very important source of sulfur for the manufacture of sulfuric acid. The sulfides of antimony, arsenic, and selenium were not used because these elements are objectionable when present in the ores to be used in the manufacture of sulfuric acid. Probably the greatest sources of sulfide ores are the extensive deposits of iron pyrites which occur in Spain. However, in the United States large deposits of this mineral occur in the metamorphic rocks of the PreCambrian extending from New Hampshire to Alabama. Pyrite 31so occurs in commercial quantities in Indiana, Illmois, Ohio, and California and in the Canadian provinces of Ontario and Quebec. Prior to the discovery of native sulfur in Louisiana and Texas, iron pyrites was exported in large quantities from Spain to European ports and to the United States for the manufacture of sulfuric acid. In this process the mineral is roasted in furnaces to moderate temperatures. The roasting process converts the ore to the oxide, and the sulfur passes out of the furnace in the form of sulfur dioxide. This gas is then collected SOURCES OF SULFUR and used in the manufacture of sulfuric acid by either The average man of today has not much greater the contact or the chamber process. One of the adknowledge of sulfur and its properties than had the vantages of this mineral as a source of sulfur lies in the

"S

ULFUR is a fatty earth thickened in the mine by boilmg until it has hardened and become dry; and when it has hardened it is called sulfur. It has a very strong composition and is of uniform substance in all its parts because it is homogeneous; and therefore its oil is not removed by distillation as is the case of other substances possessing oil. . . . Sulfur can be calcined only with great loss. It is as volatile as a spirit. When calcined with sulfur, all metals increase in weight, in a manner which cannot be questioned, for all the metals can be combined with sulfur, excepting gold, which combines only with difficulty. Mercury combines with sulfur producing a sublimate of 'uzufur' or cinnabar, but it does not transmute mercury or silver as some philosophers imagine." The above description of sulfur and its properties appears in a twelfth-century Latin version of the Arabian Geber-"Semma fierj'ectionis magisterii"-and is probably a very good summary of the scientific knowledge of sulfur available to the world at that time. Records indicate that the ancients knew of and used sulfur in early historical times. It was used about 2000 B.C. in bleaching linens, and Egyptian paintings dating as far back as 1600 B.C. contain colors requiring sulfur compounds in their making. In the early times the word sulfur was practically synonymous with fire and hence sulfur was, and is even today, commonly spoken of as brimstone; it was so called in several places in the Bible. Most of the sulfur used in the early times probably was obtained by heating either iron or copper pyrites, although Pliny in some of his writings refers to sulfur which came from islands between Sicily and Italy. Many of the ancient uses of sulfur were either similar to or identical with present-day uses. F'finy regarded sulfur as a "most singular kind of earth and an agent of great power on other substances" and describes it as having fourteen "medicinal virtues," among which were included its use as an insecticide and as a fumigant in the sick room to drive out the "evil spirits." He also recognized four diierent kinds of sulfur, evidently differing in purity, and distinguished them by their uses as follows: (a) "live" sulfur, used in medicine; (b) fuller's sulfur, employed in the preparation of cloth; (6) egula, used in fumigating wool; and (d) that used in preparing lamp wicks for easy kindling. Other records show that sulfur was burned to generate "evil-smelling" gases of warfare about 490 B.c.-disproving the common fallacy that gas warfare tactics were first used in the World War.

fact that the residue from the roasting process may be used as a raw material for the smelting of iron. Lead and zinc sulfide ores occur in the Appalachian belt along the Atlantic seaboard, in the Virginia-Tennessee belt, in the Saucon Valley of Pennsylvania, and in the upper Mississippi Valley. Mixed ores of lead and zinc, together with gold, silver, copper, etc., are ~rominentin the Cordiieran section of Western United States. In a few instances the smelters in these regions are equipped to use the by-product sulfur dioxide in the rnmmfnrtnre of but this oradice is not .. s~jlfuricacid. ~~, general. With the discovery of native sulfur in the Gulf Coastal area of Texas and Louisiana, and the development of an economic method for mining these deposits, the use of pyrite ores as a source of sulfur has steadily decreased. While free sulfur is often found in the sedimentam ---rocks of the earth's crust, it is seldom found in sufficiedt concentration to be of commercial importance. Native sulfur may be formed in several ways. The type known as solfataric sulfur is often found in fissures of lava and tuff in the vicinity of active and almost extinct volcanoes. Since hydrogen sulfide and sulfur dioxide are known to be common constituents of volcanic gases, the formation of this type of sulfur can he explained by one of the following equations: ~~~

~~

~

~

+ 2501 = HISO, 4- 25.

(1) HxS (2) 2H2S (3) 3SOz

+ = 2H20 + 2 s + 2HsO = 2H2S04 + S 0 2

Deposits of this nature are rarely of commercial importance, but a few have been worked on a small scale in Japan. Sulfur of this type has also been found in the crater of Popocatepetl, in Mexico, and several other such deposits are said to occur in the volcanic regions of the Chilean and Argentine Andes. Native, or free, sulfur is also of common occurrence in the vicinity of some mineral springs. Its formation may be explained by the incomplete oxidation of the hydrogen sulfide according to equation (2) ibove, but there is considerable evidence that the sulfur in mch vicinities may be due to bacterial action. Deposits of this type occur throughout the Western States, and a few, namely, those which occur a t Cove Creek mine, Utah, and a t Cody and Thermopolis, in Wyoming, have been worked on a small scale. Such deposits, however, are of a superficial nature, and play an insignificant part in the world production. The "gypsum type" of sulfur is found throughout the world, and is so called because of its constant association with gypsum and anhydrite. Deposits of this nature are in no way connected with volcanic activity, and their close association with sedimentary formations has made the explanation of their mode of occurrence exceedingly difficult. Many hypotheses have been advanced, but none of them has been sufficiently proved to merit universal acceptance. The most generally accepted of these hypotheses is that the sulfur has been produced as a result of the reduction of gypsum by material of an organic nature. This theory,

however, is based upon certain reactions which are known to take place a t elevated temperatures hut which have not been produced experimentally under the conditions which are known to have existed in the formations. The Sicilian deposits of Europe and the sulfur which occurs in the Gulf Coast area of Louisiana and Texas are well-known examples of the gypsum type of sulfur. THE SICILIAN SULFUR INDUSTRY

For many years the Sicilian deposits constituted a world monopoly, and prior to 1903 they were producing approximately 95% of the world's sulfur; a t present they are producing about 12% of the sulfur used. It is said that sulfur has been mined in Sicily for a t least 300 years, during which time it is estimated that some 16,000,000 tons have been produced. Competent engineers estimate that there are a t least 30,000,000 tons of sulfur yet available in the deposits. The sulfur is found in the Miocene strata and is of the gypsum type. It is closely associated with mark, shales, and gypsum, and constitutes from 8% to40% of the sulfur-bearing formation; the average will run about 24%. Fuchs and Delaney (Traitt? des Gttes Mint?raux, p. 274) state that the sulfur produced by the reduction of gypsum would constitute about 24% of the deposit; hence the fact that the content of the Sicilian deposits averages that amount is regarded as strong evidence that the sulfur is the result of the reduction of gypsum or anhydrite by the bituminous matter Before the introduction of the Frasch Drocess. the methods of mining and refining the sulfur were very crude and inefficient. The ore.was'mined and brought to the surface by manual labor, much of it child labor, and piled into large circular piles 60 to 75 feet in diameter and 7 to 10 feet deep. These piles were known as "calcaroni." The heaps were provided with floors containing pits or compartments in. which the molten sulfur was collected. When sufficient ore had been piled up, the "calcaroni" were completed by being covered over with earth or wet ashes from previously burned ore. They were then fired by dropping blazing wood fuel through holes in the top until the sulfur itself became ignited and furnished sufficient heat to melt the remaining sulfur. The molten sulfur was then drawn off from the collecting compartments into blocks of the desired size. The efficiency of the entire process was very low, since only about 60% of the sulfur charged into the "calcaroni" was recovered and its purity ranged from 90% to 98%. Needless to say there was a large amount of sulfur dioxide produced by this process which, since no effort was made to recover it, caused very serious damage to the vegetation of the surrounding country. The mines now in operation range in depth from 150 to 650 feet, and the majority of them now use a t least semi-modern mining equipment. The "calcaroni" system of extraction has been largely superseded by modifications of the regenerative furnace in which re-

covery of SO% of the sulfur is obtained. Attempts have been made to mine the deposits by the use of superheated steam and they have been successful in that as high as 90% of the available sulfur has been recovered, but the high price of fuel makes the process too expensive for general use. Another difficulty has been the fact that the formation is so near the surface that sufficientpressure could not be maintained on the water to prevent its flashmg into steam and thus dissipating the heat before the melting point of the sulfur was reached. The history of the Sicilian sulfur industry is primarily the history of many changes in managerial policy. Before 1838 all sulfuric acid was made from elemental sulfur; hence all users of the acid were concerned with the price of sulfur. Attempts had been made to use pyrites in the manufacture of sulfuric acid, and an Englishman by the name of Hall was granted a patent in 1813 for a process of manufacture, but it was not immediately adopted. The Sicilian industry progressed very smoothly until 1838, when the King of Naples became too greedy and started the sulfur racketeering by granting a monopoly on the export of sulfur to M. M. Taix et Cie. of Marseilles. The price of sulfur jumped immediately from $25.00 a ton to nearly $70.00 per ton. As a result, Hall's process for the use of pyrite for sulfuric acid manufacture was perfected arid put into.commercial use. This occasioned such a radical slump in sulfur sales that the price of Sicilian sulfur dropped to a more reasonable level, but was still kept above its former price. The Hall process was so successful that only those manufacturers who had to make arsenic-free sulfuric acid continued to use the Sicilian sulfnr. The ultimate effect was to force the abolition of the monopoly and the restoration of the former price levels, which in turn made it profitable for the acid manufacturers to abandon the use of pyrite and to resume the use of sulfur. The industry then prbg~essed very well until about 1890, when the Chance-CJsus process for the recovery of sulfur from the calcium sulfide in alkali wastes was discovered. At 61st i t was believed that this method could be applied to reclaiming the sulfur in the huge waste heaps which had accumulated at the alkali plants, but about 189G97 it was found that the greater part of the sulfides in the waste had been oxidized to. sulfates and hence were not recoverable. In the meantime, a group of English capitalists had acquired a block of Sicilian sulfur interests and considerable friction developed between them and the Sicilian producers, resulting in a sharp decrease in the price of sulfur and a radical reduction of the wages of the workmen. However, in 1897 when it was discovered that the Chance-Claus process could account for only a relatively small proportion of the yearly consumption of sulfur, the price of sulfur was fixed by speculators a t about $30.00 per ton. The users of sulfur immediately objected, and a new price war started between the English and the Sicilian producers which created much

havoc in the entire industry. The price finally dropped to about $11.00 per ton delivered in England, which price included an export tax of some $2.00 per ton. The net income was then practically equal to the cost of production a t the mine. Wages were lowered to such a n extent that the entire business structure of Sicily was endangered and political rnination was near a t hand. The English and Sicilian producers were of course making no money and soon came to realize that price fixation by certain speculators was a t the root of all the trouble and that steps would have to be taken to rectify the condition of the Sicilian workmen and the mine owners. This resulted in the formation of the AngloSicilian Sulphur Company and the subsequent stabilization of the entire industry. Capital stock of the company was $5,000,000, most of which was subscribed in England. The company had the full sanction of the Italian government and reforms were promptly brought about. Wages of the workmen were raised, child labor was abolished, the high export and income taxes were removed and a very nominal export duty imposed. All existing stocks of sulfur were taken over by the Company a t a fair price and an agreement was made to pay the producers in Sicily about $16.00 per ton for future production. The Company controll'ed 75% of the Sicilian sulfur supply, which gave i t virtual control over the entire industry. It had the right to call for a decrease of as much as 18% in production in event the demand should fall off,although with each 3% of decrease the producers were to be paid 1%more for that sulfur which wasprodnced. Within a short time, all the readjustments had been made, and tbeilnglo-Sicilian Sulphur Company wa's functioning to the entire satisfaction of both the producers and the consumers. Later on, however, when the Frasch process was perfected the officials were unable to cope with the situation, and the Company quietly and systemati,cally disposed of the sulfur stocks on hand and then disbanded. AMERICAN SALT DOMES

In 1869 sulfur was discovered a t Calcasieu Parish, Louisiana, in a well being drilled for oil. The occurrence of this deposit was coincident with that of the geological structure known as a salt dome, a peculiar formation limited largely to the Gulf Coastal Plains. At the present time there have been almost 200 such domes located in Texas and Louisiana, from nine of which sulfur has been produced in commercial quantities. Essentially, a salt dome is an intrusion of a salt plug from underneath the ground and is usually, though not always, overlaid with a limestone, gypsum, or anhydrite caprock. In general, they are dome-shaped with sharply sloping or almost vertical sides, are round or elliptical in cross-section, and range from ' 1 s to l1/9 miles in diameter. Some of the domes are flat on top, some have a slight depression in them, and some, like

the one a t Barber's Hill in Texas, have a slight "mushroom" top in which the top of the salt is somewhat flattened and spreads out beyond the sides of the core underneath in mushroom or toadstool fashion. Some

Conn

FROM

SULFUR-BEARING STRATUM AT HOSKINS MOUND

T h e areas which appear dadt in the photograph are composed of sulfur; the matrix is limestone and gypsum.

domes have been discovered in which the top of the salt is 7000 feet below the surface of the ground, while others, like the one a t Avery Island, Louisiana, have the top of the salt above the nominal surface of the ground. The exact thicknesses of the salt plugs are more or less undetermined, although some of them have been penetrated for more than a mile without any indication that the bottom of the salt was being approached. The salt of the domes which have been examined is exceptionally pure, ranging from 98.0% to 99.9% pure NaCl. The total quantity of salt in the known salt domes is too great to inspire even semiintelligent guessing. R. A. Stainmayer [Chem. 6 Met. Emg., 39, 388 (1932)l says that it has been estimated that there are 2,000,000,000 tons of salt underlying Avery Island alone. @ I n spite of the value of the salt itself, the present value of the domes lies primarily in the fact that every dome is a potential source of oil or sulfur, or both. Many millions of dollars have been spent in prospecting the various domes for these two substances, and at the present time there are over sixty domes in Texas and Louisiana which are producing oil a t the rate of over 50,000,000 barrels per year, and nine of them have produced or are producing sulfur in commercial quantities. Other domes are being prospected constantly and no doubt there will be other discoveries of both oil and sulfur which will prove as important as have the discoveries already made. The sulfur found in these domes is of the gypsum type and is similar t o that of the Sicilian deposits. In both instances the gangue material is gypsum and a porous type of limestone. The native sulfur is disseminated through the gangue, with occasional pockets of massive sulfur occurring in cavities of the gangue.

The deposits are located a t depths varying from 100 to 2000 feet, and the superimposed strata consist of pack sands and loose clay formations. The loose and friable nature of the overlying formations, together with the poisonous gases which are encountered, make it impossible to sink a shaft and mine the sulfur by underground methods. Consequently, these deposits were for many years a potential but unobtainable re. . source. When the sulfur deposit a t Calcasieu Parish was discovered, numerous attemvts were made t o sink a shaft to the level of the sulfurIbearing stratum in order to mine and refine the sulfur in a manner similar to that used in Sicily. Several American companies, an Austrian company, and a French company made numerous attempts t o obtain the sulfur, but all they did was to spend several million dollars and to kill a number of workmen. Finally Herman Frasch became interested in the matter, and in 1891, as a result of his investigations, was granted a patent on his famous hot-water process for mining sulfur.

..

:.

HERMAN FRASCH

Although the world knows him now primarily as the man who invented the sulfur-mining process, Herman Frasch was a highly successful hgineer, chemist, and inventor before he became interested in sulfur. (American Druggist, Oct., 1931, p. 64.) He was born in Germany in 1852, but came to the United States when he was only sixteen years old to continue his work as a pharmacist. For a while he worked with John M. Maisch, Director of the United States Army Laboratory during the Civil War, but later bought his own drug store in Philadelphia. Frasch paid very little attention to the actual operation of kiis drug store--he let his assistant run the store while he spent his time in the laboratory in the back of the store just "piddling around" as he himself described it. However, his "piddling" was not at all trivial because in a few years, when he was only twentyfour years old, he was granted his first patentprocess for refining paraffin wax. The oil companies then in operation had been attempting, unsuccessfully, t o refine paraffin wax for some time, rnd when Frasch's patent was announced they immediately became interested in both the man and his process. The result

was that he sold his drug store to his assistant and went to work for the Standard Oil Company. This first period of work with the Standard Oil Company lasted from 1876 to 1885. During these nine years he applied for and was granted about twenty patents, all of which had a real monetary value to both the inventor and his company. Naturally some of the patents were concerned with improvements in the refining of petroleum, but not all of them were of this character. Among other things, his patents included a process for making waxed paper, a process for making white lead directly from galena, improvements in the process of salt manufacture, improvements in the ammonia process of making sodium carbonate, a process for making elements for thermal electric generators, and several processes for the manufacture of arc-light carbons. In 1885, when his contract with the Standard Oil Company expired, Frasch decided that it was time for him to go into business for himself. Consequently he moved to Canada and organized the Empire Oil Company. At that time the Canadian oil industry was having much trouble with the odors produced by the sulfur compounds in the crude oil and the distillates therefrom. Despite very 'careful refining procedure, the kerosene, gasoline, etc., which were produced hecame known as "skunk oil" because of their nauseating and very penetrating odor. The odor was so very offensive that there is a case on record in which a boat load of flour and bacon was mined simply because it was anchored near a cargo of the Canadian oil. A short time later the courts virtually declared the oil to be a public nuisance, and the Canadian oil industry was practically put out of business. Frasch immediately started to work to find some way to remove these objectionable sulfur compounds. His first patents in this connection were applied for in February, 1887; and between that date and January 1, 1895, he applied for and was granted twenty patents relating to the refining of Canadian and similar Getroleum oils. Essentially, his refining process consisted of mixing the crude oil with certain metallic oxides, usually copper oxide, and then removing the different distillates in the usual manner. The sulfur compounds reacted with the copper oxide to form copper sulfide, leaving the distillates sweet and odorless and comparatively free from sulfur. The cost of the process was not very high, because the inventor also perfected a process in which the copper sulfide could be filtered off from the residuum and roasted, producing it again as the oxide ready for re-use. Within a year the Empire Oil Company had the process in operation on a large scale, and was producing petroleum products which were comparable with the corresponding derivatives of the purest of Pennsylvania oils. Some time before this an oil very similar to the Canadian oil had been discovered in Ohio and was being produced there in large quantities. The Standard Oil Company bought up large interests in the field, and started to refine the oil in the same manner in which

they were refining the Pennsylvania oils of low sulfur content. The burning oils were put on the market hut were soon returned to the company as being unfit for use because of the odor and the soot produced in hurning. For two years the company had their engineers and chemists a t work trying to develop a suitable refining process, but finally gave it up and decided that the oil could be sold only as fuel oil. A pipe line was built to Chicago and long-time contracts were entered into whereby the oil was sold for 14 cents per barrel. When Frasch began to have such phenomenal sucoess in rehing the Canadian oils, the Standard Oil Company made thorough investigations and then proceeded to buy the entire stock of the Empire Oil Company. Frasch was paid with stock of the Standard Company and was again placed in the research department of that company. Soon afterward large refineries operating under the same patent rights were established in the Ohio fields. As a direct result of the application of the new process, the hundred million dollar stock of the Standard Oil Company increased within a few years from $168 per share paying 7% dividends to $820 per share paying 40% dividends. In addition to this, the crude oil price jumped to $1.00 per barrel and the total production of the field was tripled. All this was due directly to the inventive and engineering ability of Herman Frasch. The inventor's successin the improvement of the oil refining process apparently did not materially decrease his efforts. During the next five years he was granted some fifteen or twenty patents exclusive of his sulfur mining patents. These patents covered fields ranging from oil refining to gold mining. During the period 1889-9 1. Fi&h became interested in the sulfur deposits in Calcasieu Parish, Louisiana, and on October 23, 1890, he made application for the basic patent on the process which has made him famous and which has proved so important that his other work, great as i t was, is almost forg~tten. His proposed mining method was so radically new that it met with ridicule and sarcasm on every hand. At that time a New York company owned the land on which the sulfur was known to exist, so Frasch, assuming that all the land in that vicinity was underlaid with sulfur, bought some land about a mile and a half away and started to develop it. He then spent much time and money sinking four wells on his land only to find that no sulfur deposit existed on it. About that time the New York company went broke, and he bought the land which this company had abandoned. Frasch's own description of his first attempt to pump sulfur is quite vivid. It is quoted direct from his acceptance speech when he was presented with the Perkin Medal in 1912. [ J .Ind. Eng. Chem., 4, 135 (1912).] I drilled a well through the alluvial deposits to the rock with a 10' pipe, then continued through the sulfur deposit, which was about 200 feet thick, with a 9" drill, and immersed a 6" pipe from the surface to the bottom of the well. The 6" pipe had a strainer only 6" long at the very bottom and a seat to receive the 3" pipe through which we expected to lift the sulfur to the surface.

The 6" pipe, directly above the seat for the 3 ' pipe, was perforated for a distance of three feet. This melting fiuid consisted of water superheated t o 335' Fahrenheit. The porosity of the rock in which the melting had t o be done seemed t o furnish an almost insurmountable obstacle to success, as I feared that the wild waters in the rock would break into the melting zone I expected to create and reduce the temperature of the fluid with which I expected to melt below the temperature necessary to fuse the sulfur. I had supplied a large number of boilers t o furnish the heat necessary to maintain a temperature higher than that required for the fusion of the sulfur. The water was superheated in columns in which 100 pounds per square inch pressure was maintained, and the apparatus which I had constructed to accomplish this proved very efficient. We used twenty 150-h.p. boilers for a well, which represents experimentation on a ponderous scale. When everything was ready t o make the first trial, which would demonstrate either success or failure, we raised steam in the boilers, and sent the superheated water into the ground without a hitch. If for one instant the high temperature required should drop below the melting point of sulfur, it would mean failure, consequently intense interest centered in the first attempt. After permitting the melting fluid t o go into the ground for twenty-four hours, I decided that sufficient material must have been melted t o produce some sulfur. The pumping engine was started on the sulfur line, and the increasing strain against the engine showed that work was being done. More and mare slowly went the engine, more steam was supplied, until the man a t the throttle sang out a t the top of his voice, "She's pumping." A liquid appeared on the polished rod, and when I wiped it off I found my finger covered with sulfur. Within five minutes the receptacles under pressure were opened, and a beautiful stream of the golden fiuid shot into the barrels we had ready to receive the product. After pumping for about fifteen minutes, the forty barrels we had supplied were seen t o be inadequate. Quickly we threw up embankments and lined them with boards to receive the sulfur that was gushing forth; and since that day no further attempt has been made to provide a vessel or mold into which to put the sulfur. When the sun went down we stopped the pump t o hold the liquid sulfur below until we could prepare t o receive more in the morning. The material on the ground had t o be removed, and willing hands helped t o make a clean slate for the next day. When everything had been finished, the sulfur all piled up in one heap, and the men had departed, I enjoyed all by myself this demonstration of success. I mounted the sulfur pile and seated myself on the very top. It pleased me t o hear the slight noise caused by the contraction of the warm sulfur which was like a greeting from below-proof that my obgct had been accomplished. Many days and many years intervened before financial success was assured, but the first step towards the ultimate goal had been achieved. We had melted the mineral in the ground and had brought it t o the surface as a liquid. We had demonstrated that it could be done. This was especially gratifying as the criticisms I had received from technical papers and people who had heard of what I was attempting t o do had been very adverse Everyone who expressed an opinion seemed t o be convinced that this thing could not be done, one prominent man offering t o eat every ounce of sulfur I ever pumped. A fair illustration of public opinion is the remark of the mail boy who drove me to the railroad the morning after our first pumping. He said, "Well, you pumped sulfur sure, but nobody believed it but the old carpenter, and they say he is half crazy." This severe criticism, while not agreeable, did not carry very much weight with me. I felt that I had given the subject more thought than my critics, and I went about my work as best I could, thoroughly convinced that he who laughs last, laughs best.

Although the first pumping of sulfur had demoustrated beyond a doubt that his fundamental idea was sound, Frasch still had many financial and mechanical

EARLY PRODUCTION MBTIIODS Note that the wells discharge directly into the vat. Note also the cone of solid sulfur built up a t point of discharge. The interiors of such cones remained molten for several months after cessation of pumping into the vat.

difficulties to overcome. The actual pumping was for a while a most annoying source of trouble. The ordinary pumps were subject to such rapid corrosion that the valves were unfit for use after only a few days' pumping. Since zinc and aluminum were about the only two metals unaffected by the molten sulfur, special valves of these metals were made up and tried. They were not corroded, hut they were too soft to withstand the constant pounding to which they were subjected a t every change of stroke of the pump. Finally, the air-lift principle was tried, and i t proved so successful that even today i t is the,one3accepted method for removing the-liquid sulfur from the wells. As the sulfur was melted and pumped out from within the vicinity of a well, the earth above the sulfur stratum settled down into the vacant space left by the sulfur. This shifting frequently proved disastrous t o the wells by pulling the 10" c&ng completely in two, and the well would have to be abandoned. After several such experiences this situation was remedied by surrounding the 10" pipe with a flexible casing of 12" pipe equipped with stuffing boxes in such a manner that they would "give" as the earth shifted. Later it became necessary to pump into some of the wells huge quantities of sawdust and mud in order to seal off the cold water which was seeping in and cooling the dome below the melting point of the sulfur. This procedure helped to some extent but did not entirely stop the influx of cold water. A NEW SULFUR INDUSTRY

Despite these difficulties-and the large-scale and high-priced experimentation required to remedy themthe Union Sulphur Company, which was organized by Frasch, finally began to show a profit on its investment. 35,000 tons of sulfur were produced in 1903, while in 1904 enough sulfur was mined to supply the entire de-

mand of the United States, and, in addition, to ship the first cargo of American sulfur abroad. The shipment of the first sulfur to France, in 1904, brought about the culmination of a series of negotiations between Frasch and the Anglo-Sicilian Sulphur Company, a holding company which controlled at that time about 80% of the output of Sicilian sulfur. At the outset the English company had investigated the new process but had pronounced it fantastic and utterly unworkable. Later, along ii 1903 and 1904. the western agents of the company complained of competition caused by the sale of "sulfur furnished from a mine which was no mine a t all, but where the sulfur came out of the ground ready to ship." Nevertheless the company persisted in denouncing the th'mg as "impossible" and another "American swindle." By that time the production of the Union Sulphur Company was rapidly exceeding the domestic demands. Frasch, in his acceptance speech [J. Ind. Eng. Chem., 4, 139 (1912)], describes the situation as follows: I was very anxious to get all the business possible, as our stock pile was much larger than our hank account, and I was surprised to hear that the Anglo-Sicilian Company had accepted a contract for 20,000 tons t o be delivered in America. very much below the price they generally quoted, and not far above their cost. I decided to go t o London and have a talk with them in order t o find out if it would be necessary for us to put the price below their cost in order to maintain the American business which we needed very badly. I was perfectly frank and explained our positidn fully. I met with a great lack of enthusiasm for the "American humbug." and was told that they would go their own way, and I could go mine. I did. I had arranged for the sale of our sulfur in the various European countries, and knowing the production cost of my competitors, I succeeded very shortly in demonstrating that Louisiana sulfur was not a swindle. I found out afterwards that the lesson had cast the Anglo-Sicilian Company 285,000 pounds sterli-but then we were friends. Their attitude changed greatly, and they decided t o go out of business and let the Sicilians and Americans take care of themselves.

Soon after the Anglo-Sicilian Sulphur Company had disbanded, Frasch and his associates sawrthat if they

continued to undersell the Sicilian sulfur in the European market, there would undoubtedly be war and revolution in Sicily. Consequently, an agreement was entered into with the Sicilian government which proved so successful that it is still in effect. Essentially this agreement permits the Sicilian mines to operate at practically full capacity and to maintain a price level which assures the miners of a fair return for their labor and investment. By this time Frasch was again recognized as one of the outstanding industrial leaders of the world-instead of the "fanatic" and "American humbug" that he had been labeled only a few years previous. He had been granted ten patents relative to the apparatus for and process of mining sulfur. He had proved himself to be a man who was willing to finish an undertaking despite criticisms, ridicule, disappointments, and high costs of experimentation. He had given to his adopted country a supply of one of the raw materials necessary to the industrial growth of the nation and he had made available within the country one of the raw materials most essential to the national defense. In 1912, as a result of the success which Frasch had attained with his many and varied endeavors, the Society of Chemical Industry bestowed upon him the highest professional honor which could be grantedthe Perkin Medal for Distinguished Service in the Field of Applied Chemistry. The opinion of his professional associates a t the time was appropriately, though humorously, expressed by Capt. A. F. Lucas at the time of the presentation of the medal: Since the advent of sulfur no serious attempt has been made to explore the sources of heavy oil that still flows from the upper Layer of some old test w e l l ~ a n dI am of the opinion that if Mr. Frasch were to make a serious &.tempt he would succeed not only in getting the oil in gushers, but also little Chinamen with &-crackers from the nether regions.

Frasch died two years later, with the full knowledge that his process was a success mechanically and financially and that his ability as a chemical engineer was fully recognized by the other men in Eis profession.