BORAX TO BORANES

Development of the

Borax

and

Present

Status

Industry

Downloaded by CORNELL UNIV on October 3, 2016 | http://pubs.acs.org Publication Date: June 1, 1961 | doi: 10.1021/ba-1961-0032.ch003

W. A. GALE American Potash and Chemical Corp., Whittier, Calif.

The borax industry in the U. S. may be divided into four periods: discovery of borax in California in 1856 and the recovery of borax from Borax Lake in Lake County from 1864 to 1868; starting in 1872, recovery of borax from surface crusts of playa (marsh) deposits in Nevada and California; underground mining of colemanite (Ca B O .5H O) in the Calico Mountains of California starting in 1887; and direct recovery of sodium tetraborate from the brines of Searles Lake starting in 1919, and from the borate ores of the Kramer deposit of Kern County, California, starting in 1927, to supply the major portions of the world's borax requirements. South America was a major producer of borate ores from 1881 to 1887, but in recent years mining has been very limited. Italy and Turkey have their own domestic industries, while the development of the Inder deposits in Russia in 1936 has seemingly made that country also self-sufficient in this regard. 2

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The element boron is widespread in nature and is estimated to constitute about 0.001% of the earth's crust (5). Besides being present to the extent of a few parts per million in sea water, it occurs as a trace element in most soils and is an essential constituent of several rock-forming silicate minerals such as tourmaline and datolite (9). The presence of boron in extremely small amounts seems to be necessary in nearly all forms of plant life, but in larger concentrations it becomes toxic to vegetation. However, in only a limited number of localities are high concentrations of boron or large deposits of boron minerals found in nature, and the more important of these seem to be primarily of volcanic origin. Usually spring waters, issuing from the depths of the earth, ultimatelyfindtheir way into streams and rivers to be carried away to the oceans. However, in many arid areas, soluble minerals brought to the surface by hot springs are not always continually removed. These waters may soon be evaporated, either in the immediate vicinity of the springs, or after subsequent accumulation as lakes in closed basins without overflow. This latter situation apparently occurred in certain localities on a large scale during past ages of intensive volcanic activity, particularly in Tertiary and Quaternary times. Large quantities of boron-bearing waters from subterranean sourcesflowedfrom hot springs in these areas for long periods. At least a portion of such waters became entrapped in landlocked depressions and was subsequently evap13 BORAX TO BORANES Advances in Chemistry; American Chemical Society: Washington, DC, 1961.

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orated. The borates carried b y these waters, following probable reaction with surface minerals such as carbonate rocks and the salines of such basins, gradually accumulated as beds of alkali and/or alkaline earth borates. Subsequently, various changes and alterations may have occurred i n these borate deposits down through the ages, but the important factor has been the continuation of conditions of very hmited rainfall. Of necessity, this had to be insufficient to wash away the more soluble borate minerals into rivers destined to reach the oceans, or to cause the more or less complete removal by erosion of former deposits of the less soluble calcium borate minerals such as colemanite. Thus, the gradual accumulation of large deposits of borate minerals on the surface of the earth i n previous geologic eras and their subsequent survival down through the ages, even with partial protection by burial under other sedimentary or alluvial deposits, have been possible only i n extremely arid regions. A s a result, the world's important commercial deposits of borates are to be found only i n such localities as the barren wastes of south-central and southwest Asia, portions of Asia M i n o r , the pampas of South America, and the desert areas of the southwestern United States, all of which are immediately adjacent to regions of former intensive volcanic activity.

Borax in Early Times I t is not known when borax was first discovered, but legend has i t that the ancient Babylonians more than 4000 years ago sent emissaries to bring strange crystals from across the Himalayas for use i n the working and welding of gold {16). T h e Egyptians are believed to have been familiar with borax and i t is said that, during the first century A . D . , the Roman emperors Caligula and Nero used to scatter "borax" on the ground after gladiator combats. However, this may have been a calcium borate, because there is evidence that the early Romans had stumbled upon the pandermite deposits i n Asia M i n o r and had done some mining there. Some time before 300 A . D . , borax glazes made their appearance i n China. About 400 years later an Arabian alchemist, named Geber, used the word "baurach," the arabic name for borax, i n his manuscripts. However, i t was seemingly M a r c o Polo who brought the first authentic specimens of borax to Europe from Mongolia i n the late 13th century. This material had the Sanskrit name of "tincana," from which we have obtained the mineral name tincal. B y the middle of the 16th century, according to Agricola i n his " D e R e M e t a l l i c a " (1), the use of borax as a flux had become well known throughout Europe, although there was still considerable confusion as to its nature. Except for the small amounts of borate materials from Asia M i n o r , most of the ancient trade i n borax seems to have come from the L a d a k h district of Kashmir, and to the east from the desert regions of Tibet. I n these areas, the borax occurs as masses of opaque crystals and surface crusts on the beds of several dry lakes at elevations up to about 15,000 feet. The source of the borax is said to be the waters of hot springs at numerous locations i n this area (19). Crude borax from these Tibetan sources is said to have been gathered by natives and transported to Lhasa to be bartered for cowrie shells and other commodities. Traders then carried the borax 500 miles over the Himalayas to Calcutta i n packages of 20 to 40 pounds each, lashed to the backs of sheep. F r o m Calcutta, caravans and later sailing vessels distributed the product to the west along the various trade routes from the Orient. Refineries were established first i n Venice and later i n other European cities.

Italian Borate Industry I n 1777, the presence of boric acid, then known as " s a l Sedativum," was noted i n the waters of some of the hot springs, "soffioni," of Tuscany, and about 1818, Francois BORAX TO BORANES Advances in Chemistry; American Chemical Society: Washington, DC, 1961.

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Borax Industry

de Larderel, a Frenchman living i n Italy, began recovering boric acid by evaporating these waters. B y 1827, this source was supplying most of the European borax and boric acid markets and continued to do so for approximately 45 years, until about 1872, when borax from the Western Hemisphere began to take over much of the trade (7).


Discovery of Borax in California On January 8, 1856, John A . Veatch found that the waters of a spring i n Tehama County, about 8 miles east of R e d Bluff, Calif., contained small amounts of borate. D u r i n g the months that followed, he found traces of boron i n a number of other springs i n various parts of northern California. This lent encouragement for further search, and i n September of the same year, he found crystalline borax i n the muddy bed of a small shallow lake, now known as Borax Lake, i n Lake County, about 75 miles north of Petaluma. A second visit to this lake the following year disclosed the possibility of recovering commercial quantities of borax from this source. As a result of D r . Veatch's discoveries, the California Borax C o . was formed under the direction of W . 0 . Ayers, and i n 1864 the commercial recovery of borax from Borax L a k e was started. The mud was taken from the lake bottom through cofferdams, which could be moved from place to place and then bailed out. The crystals of borax were separated from the m u d , washed, dissolved i n hot water, and r e crystallized (21). F o r the next four years these operations produced an average of about 150 tons per year and supplied the limited borax needs of the United States. However, a rise i n water level i n 1868 made the operations unprofitable.

Playa (Marsh) Deposits About 1870 or 1871, small amounts of ulexite were found i n Nevada a few miles east of M o n o Lake. However, this attracted little attention, and the real U . S. borax industry may be said to have actually started in 1872, with the discovery of crystalline borax (tincal) at TeeFs marsh, i n the same locality. This was the first commercially profitable borax deposit i n the U . S., and may be regarded as the beginning of the second period i n the borax industry of the West (21). About the same time similar playa deposits were discovered at nearby Rhode's marsh, at Columbus marsh, and i n Fish Lake Valley, all i n Esmeralda County, Nevada. I n California, John W . Searles began operations on the mud flats surrounding a dry lake, now known as Searles Lake, i n northwestern San Bernardino County, and a few years later, borax recovery also began i n Saline Valley i n Inyo County. The method of recovery used i n most of these marsh operations was relatively simple, although crude. The incrustations on the surface of the m u d flats were harvested and leached with hot water i n dissolving tanks, and the mud was allowed t o settle. The clear solution was then run to cooling vats, where borax crystals formed slowly on the bottom and sides, to be later removed, recrystallized, and packed for shipment. I n most cases, the product had to be hauled by mule teams, either a l l the way to the coast, or many miles to the nearest railroad. Similar operations began about 1882 i n Death Valley and i n nearby Amargosa Valley. However, the surface crusts of these deposits, together with most of those being worked i n Nevada, contained numerous lumps of a fibrous form of ulexite, known as "cotton b a l l . I n fact, i n many of the deposits the borate present was entirely i n this form. A t first this was discarded b y the average prospector, but i t was soon found that this material could be treated with soda i n the boiling and leaching operations, to give a moderate yield of borax. Also, i t was soon recognized that the borate content of these salt crusts was secondary i n nature, having been formed by evaporation of borate-bearing waters (3). The search for the primary sources of the borate soon led prospectors to the mountains east of Death Valley, where a small deposit of bedded ulexite was found i n place i n the Tertiary lake ,,

BORAX TO BORANES Advances in Chemistry; American Chemical Society: Washington, DC, 1961.


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sediments that constituted many of the rock formations of that region. Here also in October 1882 a new mineral, colemanite ( C a B O - 5 H 0 ) , was discovered (12). 2

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Colemanite Mining I n the following year the discovery of a large and more readily accessible bedded deposit of colemanite i n the Calico Mountains near Daggett, Calif., resulted i n 1887 i n the transfer of borax mining activities to that locality, which was soon providing the greater part of the world's requirements. This discovery was the beginning of the third, or colemanite, period of the borax industry which thus became revolutionized. These deposits were much more extensive, more easily accessible, and i n purer state than the marsh (playa) deposits. M o s t of the latter i n Nevada and Death Valley were gradually abandoned as no longer economical. I n California, the playa operations at Searles Lake ceased i n 1896, but those i n Saline Valley continued to about 1908. I n handling the major portion of the colemanite i n the Calico District, the mined ore from underground workings was first crushed and then calcined i n a roasting operation sufficient to dehydrate the colemanite and cause i t to fall away to a powder, thus permitting it to be separated from the coarser gangue material by simple screening (21 ). These concentrates were then shipped to refineries to be converted to borax by digesting with hot sodium carbonate solutions, followed b y filtration and crystallization. After these deposits began to approach exhaustion a few years later, colemanite mining operations were transferred i n 1903 to the mountains immediately east of Death Valley, where additional deposits of calcium borates had meantime been found in the Furnace Creek area and i n the nearby district around R y a n . These proved to be extensive and far excelled those previously worked i n the Calico Mountains. A t first, all mining operations were by means of shafts and underground drifts, but i n the years that followed, several "glory hole" type of mines were developed. The ore was mainly colemanite, but lesser amounts of other borates were present which did not decrepitate on roasting. This necessitated the modification of the concentration methods originally used. This was done by incorporating gravity separation methods, such as Wilfley tables, on the recrushed residue from the roasting and screening operations (21). Although these mines supplied the greater part of the world's requirements of borate ores during this period, the operators were not alone i n the field. Several other bedded deposits of calcium borates, mainly colemanite, had been discovered i n the southwest, and were mined on a fairly large scale.

Direct Recovery from Sodium Borate Deposits However, the industry was due for another revolution, with the discovery of an enormous ore body of sodium borate, buried beneath the sands of the Mohave Desert in the K r a m e r District in southeastern K e r n County, California, i n 1925 (18). This deposit came into production i n 1927, marking a new era i n the California borax industry. This has since become the world's largest single source of borax. A l l colemanite operations i n Death Valley and elsewhere in this country were soon closed down because they could no longer compete with the more economical direct production of sodium borates at K r a m e r , and at Searles Lake. This huge deposit at Kramer, or Boron as it is now called, is about one mile wide and four miles long, with an ore body varying from 80 to about 250 feet i n thickness (10). The run-of-mine ore averages about 2 5 % shale and 7 5 % hydrated sodium tetraborate i n the form of both the decahydrate (tincal) and a previously unknown compound, the tetrahydrate (kernite, N a B 0 - 4 H 0 ) . Underground mining methods have been used b y the Pacific Coast Borax C o . (now a division of U . S. Borax and 2

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Chemical Corp.) for the past 30 years, but at present, open-pit mining is being developed. However, this necessitates a herculean task of removing from 300 to 400 feet or more of overburden. A variety of ore-dressing methods are used i n processing the ore, depending primarily upon the type of concentrates desired, whether for domestic use as such, for direct refining b y recrystallization, or for export as a crude product. M u c h of the shale can be removed b y high intensity magnetic separation, while calcining, screening, tabling, air classification, etc., all find their place in the various beneficiation steps (6,16).


Searles Lake Brines Following the abandonment of John Searles' operations at Searles Lake i n 1896, no borax was recovered from that source until 1919, when borax became a by-product of potash recovery. Starting i n 1916, potassium chloride was recovered from the brines of the main salt body of Searles Lake. This deposit extends over an area of between 30 and 40 square miles, with a depth of 60 to 130 feet. The salt body is porous and the interstices contain a saturated brine which makes up over 4 0 % of the volume of the deposit. This brine is pumped from wells sunk into the lake bed, and is evaporated to produce a hot concentrated liquor which can be cooled to crystallize crude potassium salts. However, these salts were soon found to be seriously contaminated with borax and i t became obvious that this impurity would have to be separated as a necessary by-product (17). Late i n 1918 i t was found that rapid cooling would cause the potassium chloride to crystallize free of borax, which would remain i n solution i n a supersaturated state to be recovered later as a separate crop. This could then be recrystallized as refined borax. Since that time the American Trona Corp., and its successor, the American Potash and Chemical Corp., have been producing a substantial proportion of the world's supply of borax (20). I n addition, another type of process for the recovery of borax is now in operation at two plants on Searles Lake, the West E n d Chemical Co. (a division of the Stauffer Chemical Co.), and the carbonation plant of the American Potash and Chemical C o r p . I n general, this method (13) consists i n carbonating the alkaline brine with carbon dioxide gas to precipitate sodium bicarbonate as a means of sodium carbonate r e covery. A t the same time the borax content of the brine becomes partially acidified to form the highly soluble sodium pentaborate ( N a B O ) . After the bicarbonate crop has been filtered off, a portion of fresh raw brine is added to adjust the alkalinity back to that of the tetraborate. The mixture is then cooled to bring about the crystallization of a substantial crop of borax. These methods now contribute greatly to the total output of borax from Searles Lake. A small amount of borax has also been recovered at times as a by-product of sodium carbonate operations on Owens Lake, but this quantity has been insignificant and the major portion of the world's supply is now coming from the two localities i n the Mohave Desert, the K r a m e r deposits and Searles Lake, about 50 miles apart. 2

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The Borate Industry in Other Countries The Italian operations in Tuscany have been mentioned. Besides recovery of i n creased amounts of boric acid, ammonium salts, and carbon dioxide from the steam vents, considerable electric power has been developed i n recent years. The plants were destroyed during W o r l d W a r I I , but have since been rebuilt and are now operating on a sufficient scale to supply most of Italy's domestic borate needs (8) while the power output is in excess of 100,000 k w . (14). Little authentic information is available concerning the present status of the borax industry in the U.S.S.R. Prior to 1936, all the borax and boric acid were made from imported materials, but the development of the borate deposits of the Inder Lake }




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region in western Kagakstan (north of the Caspian Sea) resulted in the country's becoming more or less self-sufficient in this regard (2). However, some boric acid was imported during and immediately after World War II. The Inder deposits contain a whole series of calcium and magnesium borates, and considerable work has appeared in the Russian chemical literature in recent years on the phase relations involved. Officialfiguresare lacking, but an estimate (4) made in 1940 indicated a production of 25,000 to 30,000 tons of boron compounds annually. In addition to the borate minerals, the so-called "deep brines" which permeate the 36-meter thickness of salt bed of Inder Lake, also contain recoverable amounts of boron (11). The occurrence of boron minerals has been reported from time to time in various parts of Siberia, but there are no indications that any of these have commercial possibilities. The original sources of borax in Tibet are now available to the Russians through Red China. The Turkish deposits in Asia Minor were worked since ancient times. Modern mining began in 1865 and has been carried on more or less continuously, ever since. The principal mineral has been pandermite, but considerable colemanite and other calcium borates have been found by recent drilling operations. The U. S. Bureau of Mines Minerals Year Book shows the production of 13,730 metric tons of ore for the year 1953. In South America the mining of borate ores began in Chile in 1852, but did not develop on a large scale until 1881, when for a while South America was the principal source of world supply, prior to the colemanite developments in California. Peru also produced ulexite for many years, but since 1917 output has been very limited. The salt pans or dry lakes of northwestern Argentina were also a source of borates in years past; however, an interesting deposit has been developed in this locality in recent years (15) : the Tincalayu borax mine, in the province of Salta. In addition to massive tincal, this deposit also contains kernite, together with a new sodium borate mineral, ezcurrite (Na B 0i7-7H 0). Small amounts of magnesium borate minerals occur in Korea, and in oceanic salt deposits, such as the Stassfurt deposits in Germany, where the mineral boracite (Mg B O -MgCl ) has been a minor commercial source of borates since the early days of the German potash industry. Small borate deposits have been worked in a very limited manner from time to time in various other countries; however, the complex and usually poor quality of the ores and the remote and usually inaccessible locations have rendered these operations unprofitable in comparison with the rich and easily accessible deposits of California, which now produce the greater part of the world's boron requirements. 4

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Literature Cited (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) (14) (15) (16) (17) (18)

Agricola, Georg, "De Re Metallica," Basileae, 1556. Berlin, L. E., J. Chem. Ind. (U.S.S.R.) 16, 3-7 (1939). Campbell, M. R., U. S. Geol. Survey, Bull. 200 (1902). Chem. Ind. (Düsseldorf) 1940 (Nos. 42, 43), 623-4. Clarke, F. W., Washington, H. S., Proc. Natl. Acad. Sci. U. S. 8, 108-15 (1922). Connell, G. A., Abstracts, 106th Meeting, A C S , Pittsburgh, Pa., September 1943, p. 1F. Conti, Ginori, Chem. Markets 32, 520 (1933). Coppa Zuccari, G., Chim. & ind. (Paris) 63, 382-4 (1950). Dana, E. S., "The System of Mineralogy," 6th ed., Wiley, New York, 1899. Gale, H. S., Calif. J. Mines Geol. 42, 325-78 (1946). Grushvitskiĭ, V. E., Byull. Inst. Halurgii 1939, (3), 47-64; Khim. Referat. Zhur. 2 (6), 89. Hanks, H. G., Calif. State Mines Bur. 3rd Ann. Rept., pp. 1-102, 1883. Hightower, J. V . , Chem. Eng. 58, No. 5, 162-3 (1951). Keller, W . D . , Valduga, Adriano, J. Geol. 54, 327-34 (1946). Muessig, Siegfried, Allen, R . D., Econ. Geol. 52, 426-37 (1957). Pacific Coast Borax Co. "Story of the Pacific Coast Borax Co.," Ward Ritchie Press, Los Angeles, 1951. Ropp, Alfred de, Jr., J. Ind. Eng. Chem. 10, 839 (1918). Schaller, W . T., Am. Mineralogist 12, 24-5 (1927).


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(19) Schlagintweit, H. von, München Acad. Sitzber. 8, 518 (1878). (20) Teeple, J. E., "Industrial Development of Searles Lake Brines," A.C.S. Monograph 49, Chemical Catalog Co., New York, 1929. (21) Ver Planck, W. E., Calif. J. Mines Geol. 52, 273-91 (1956).


BORAX TO BORANES

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