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By D. S. Dinsmoor

Boron, estimated to comprise about 0.001 percent of the earth's crust (Fleischer 10), as an element is never found free in nature, although its compounds are found in many localities. the borates are the most important. Sassolite (B(OH)3) and boracite (Mg6C12B1406), non-borates, are-of-minor importance. The crystal structures of most natural borates are still unknown. A classification based solely on the ratio of boron to the total number of cations has been devised (Palache 28). This classification divides the borates into four, sub-groups; anhydrous borates, hydrated borates, borates containing hydroxyl or halogen and compound borates. Only four or five minerals of the hydrated borates group have ever been used commercially. In more recent years, the sodium borates have comprised all but a 'small fraction of all borates used. Borax, the hydrated borate compound, is the most important of all boron compounds. It has been used so long and so often that the layman often confuses borax and boron and, applies the terms synonymously.

Jan 1, 1958

By Robert B. Kistler, Ward C. Smith

The borate industry is one of the few sectors of the mining and mineral-processing industry which the United States still dominates. Since about 1927, the United States has supplied over half of the world's total boron and borate raw materials, and many of the chemical derivatives as well. Chiefly responsible for this record are companies producing sodium borates from two large deposits in southern California, at Boron (Kramer) and Searles Lake. The sodium borates, or products derived from borax and borax-containing brines, are the preferred borates for industry because they are soluble in water and combine readily with most other chemicals. Calcium borates (or sodium-free compounds) are required for certain end uses, but in general, nonsodium borates are used only where borax is not avail- able. During the past hundred years, the use of boron compounds throughout the world has risen from a few tons per year to the equivalent of about a million tons of B2O3. Leadership in supplying borates has shifted from country to country and from region to region during this period, generally as the result of the development of newly discovered deposits that were better in quality, more accessible, or more economically exploitable than previous sources (Table 1). Primary Products and End Uses The principal borate products offered by primary producers in the United States are listed in Table 2. In general, these products are utilized worldwide by almost all consumers, regardless of the original source of the primary borates. In the United States, the primary borates all originate in southern California. Colemanite is produced as crude or processed crude ore from the Death Valley area and is utilized by the fiber glass and ceramic industries without further treatment. Production from Searles Lake, Calif., is from brines that are processed in chemical plants where borax and other compounds are recovered and the principal borate products are produced. At Boron, Calif., the world's leading producer is mining a deposit of mineral borax and operating a chemical refinery. The mineral borax is mined together with included clay, and refined borax or "lo-mol" is one of the refinery products. The mineral and the chemical compound are identical, Na2B4O7- lOH2O. In addition to ship- ping all major refined borate products from Boron, the company ships semiprocessed ore concentrates to treatment plants elsewhere.

Jan 1, 1975

By Cahit Helvaci, Robert B. Kistler

Borates are defined as ' 'salts or esters of boric acid; a compound containing the radical B203" (Bates and Jackson, 1987). Borates are defined by industry as any compound that contains or supplies boric oxide. A large number of minerals contain boric oxide, but the three that are the most important from a worldwide commercial standpoint are: borax, ulexite, and colemanite. These are produced in a limited number of countries (Fig. 1), dominated by the United States and Turkey, which together furnish about 90% of the world's borate supplies (Lyday, 1991). Production in the United States originates in the Mojave Desert of California; borax and kernite are mined by US Borax from its large deposit at Boron. Borate containing brines are pumped from Searles Lake by North American Chemical Co., and a limited amount of colemanite is mined by Newport Mineral Ventures from Death Valley. Turkish production is controlled by Etibank, the national mining enterprise, which supplies most of the commercially traded ulexite and colemanite from mines in the Bigadic and Emet Districts, plus borax from the huge deposit at Kirka. Borate minerals have been employed in a wide range of uses for many centuries, dating from at least the 8th century when they were used primarily as a flux for assaying and refining gold and silver. Their valuable properties and relative rarity soon stimulated international trade in borates; Marco Polo claimed to have trans- ported Chinese borate minerals from Tibet to Europe, and his home port of Venice was the center for borate imports and use throughout the Middle Ages (Travis and Cocks, 1984). Borates were traded at relatively high prices for highly specialized applications into the late years of the 19th century. At that time they were being used for medicines, food preservatives, ceramic glazes, and in expanded applications as metal fluxes. It was in that era that borax was discovered in Clear Lake, CA, and more significantly, the playa deposits of western Nevada were found and exploited by F.M. "Borax" Smith and others. Research and development by Smith's company began the evolution of borates from a high priced commodity with a few specialized uses to the relatively low priced chemical raw material used in large tonnages on a worldwide scale today. Borates are often defined and sold by their boric oxide or B,03 content, and most statistical data are listed in tons of B203. Of the products sold by the industry, borax pentahydrate or 5 mol and boric acid are the most commonly traded commodities. Boric acid plants are operated by all of the major borate producers. Glass fiber insulation is the major end use in the United States followed by textile glass fiber and borosilicate glass, detergents, and ceramics. Detergent usage continues to be a major end use in Europe.

Jan 1, 1994

By Robert B. Kistler, Ward C. Smith

The borate industry is one of the few sectors of the mining and mineral-processing industry which the United States still dominates. Since about 1927, the United States has supplied over half of the world's total boron and borate raw materials, and many of the chemical derivatives as well. Chiefly responsible for this record are companies producing sodium borates from two large deposits in southern California, at Boron (Kramer) and Searles Lake. The sodium borates, or products derived from borax and borax-containing brines, are the preferred borates for industry because they are soluble in water and combine readily with most other chemicals. Calcium borates are required for certain end uses, and these are produced from smaller colemanite-ulexite-probertite bodies. Sodium-free borate compounds also are produced from boric acid, which can be manufactured from either sodium or nonsodium borate minerals. During the past hundred years, the use of boron compounds throughout the world has risen from a few tons per year to the equivalent of over a million tons of B2O3. Leadership in supplying borates shifted from country to country and from region to region during this period, generally as the result of the development of newly discovered deposits that were better in quality, more accessible, or more economically exploitable than previous sources (Table 1). Primary Products and End Uses The principal borate products offered by primary producers in the United States are listed in Table 2. In general, these products are utilized worldwide by almost all consumers, regardless of the original source of the primary borates, In the United States, the primary borates all originate in southern California. Colemanite is produced as crude or processed crude ore from the Death Valley area and is utilized by the fiber glass and ceramic industries without further treatment. Production from Searles Lake, CA is from brines that are processed in chemical plants where borax and other compounds are recovered and the principal borate products are produced. At Boron, CA, the world's leading producer is mining a deposit of mineral borax and operating a chemical refinery. The mineral borax is mined together with included clay, and refined borax or "10-mol" is one of the refinery products. The mineral and the chemical compound are identical, Na2B4O7 • 10H2O. In addition to ship¬ping all major refined borate products from [ ]

Jan 1, 1983

By James M. Barker

Jan 1, 1985

By Egil Krystad, Merete Tangstad, Kai Tang, Gabriella Trenell

"A new UMG-Si refining concept has been proposed in this paper. Liquid Si and another liquid metal phase (Me) were separated by the molten slag spontaneously based on their different physicochemical properties. Two metal/slag distribution reactions are able to occur in the system simultaneously. Experimental investigation on the B and P distribution equilibria among Si/slag/Me was carried out in the graphite resistance furnace under the inert atmosphere. The B and P doped silicon was in equilibrium with either the SiO2-CaO or SiO2-CaO-l0%CaF2 slags at 1600 and 1650°C, respectively. The pure Fe and Cu metals were used in order to ""capture"" B and P in the slag phases. B and P in samples were determined by the ICP-MS. B and P distribution coefficients for the Si/slag/Me equilibria were compared with the theoretical calculations. The possible kinetic barriers for the Si/slag/Me three-layer equilibria have been analyzed. The metal contaminations in the three-layer equilibria were also examined. The present study provides a new approach for the refining of MG-Si.IntroductionMost of the impurities in the metallurgical silicon (MG-Si) are rather ""dilute'', ranging from few to several thousand ppms. However, the target impurity levels for upgrade metallurgical silicon (UMG-Si) feedstock are often far below the level of ppm. In such extreme case, the conventional refining technologies face the great technical challenges. B removal by slagging has already been implemented industrially. Removal of Pis frequently carried out by the vacuum distillation. The separating treatments for B and P removals lead to increase refining cost, total CO2 emission and longer pay-back time of solar cell module.It is well known that the phosphate capacities of slags in equilibrium with liquid silicon are extremely lower. However, if we introduce another phase that possesses high ""phosphor capacity"" into the Si/slag system, one would expect to continuously remove P from Si through molten slag to the new ""phosphor capturer"". The so-called three-layer refming concept is thus proposed in the present study. Liquid Si and another liquid phase (Me) are separated by the molten slag spontaneously based on their different physicochemical properties. Two metal/slag distribution reactions are able to occur in the system simultaneously."

Jan 1, 2013

By Patrick R. Taylor

Sub-micron sized boron carbide powders have been synthesized in a non-transferred arc thermal plasma reactor. Precursors for this synthesis are boric acid or boron oxide powders and methane. The powders produced were characterized in terms of size, shape and purity. Methods to increase the purity of the product were evaluated and included hot water leaching to remove unreacted oxides and controlled temperature, air roasting to remove excess carbon. Theoretical results are also presented on the thermodynamics and mechanisms of the synthesis reactions.

Jan 1, 1994

By F. W. Libbey

Jan 1, 1985

By M. C. Udy, P. C. Rosenthal

THE use of minute boron additions to steel has been given considerable attention in recent years. Comparisons made between boron-free and boron-containing heats of otherwise identical analysis have indicated, beyond a doubt, the potent effect of boron for increasing hardenability. The actual hardenability increase has been expressed as a multiplying factor, or in terms of the percentage of other alloying elements boron might replace, The present study presents the results of a systematic survey of. the use of boron as an addition to two types of alloyed steels and as a replacement for various percentages of molybdenum in these steels, Both cast and wrought steels of the two basic compositions were prepared. Molybdenum, because of its scarcity at the time the investigation was started, was selected as the element to be replaced by boron. Attention was also given to the effects of boron on other properties of the steels, particularly their notched-bar toughness, to investigate other advantages or limitations of this element as an alloy addition. EXPERIMENTAL WORK Steels Investigated The two basic compositions used in this survey of boron as a replacement for molybdenum are given in Table I. The cast steels were higher than the wrought steels in silicon content to improve the casting quality. [ ] Each of these base steels, both cast and wrought, was made with molybdenum contents of o, 0.10, 0.20, 0.30, or 0.40 per cent, the total comprising 20 steels. In addition, each of these 20 compositions . was prepared with boron additions in amounts of 0.0015, 0.003, and o,006 per cent as ferroboron; and in amounts of 0.002 and 0.005 per cent as two com¬mercial intensifier alloys, designated alloys A and B. The boron-treated steels totaled 100, and the entire series 120, Test Procedure Each steel was melted as an individual heat in a 50-lb., magnesia-lined induction furnace. Ingot iron scrap or mixtures of ingot iron and steel scrap were used for melting stock. Deoxidation was carried out in the furnace with o.10 per cent aluminum. The aluminum addition was

Jan 1, 1946

By Takeshi Yoshikawa

For the development of low-cost silicon refining process for solar cells, the present authors have been studying the low temperature refining technique, ?solidification refining of Si with Si-Al melts at 1173 ? 1273K?. In the present work, we have investigated the B removal in that refining, utilizing the segregation effect and also the effect of Ti addition to the melt. Segregation ratio of B between solid Si and Si-Al melt was measured by the temperature gradient zone melting technique and it indicated the B removal fraction would be as much as 90%. Titanium addition to the melt was found to produce the TiB2 precipitation with soluble B in that melt and bring the effective B removal of refined Si to its content of 1ppma.

Jan 1, 2006

By K L. Avarmaa, M A. Rhamdhani, A D. P Putera, H T. B M Petrus, G A. Brooks

Multistage slag treatment was carried out to investigate boron removal from metallurgical grade silicon. Boron is known to be one of the most difficult elements to remove from silicon. Depending on boron initial concentration, boron can be removed from silicon into certain level; most previous studies have attained final 50–100 ppmw (parts per million weight) boron in the silicon using slag treatment. The term ‘multistage’ refers to a process where the resulting silicon from the initial slag treatment is further refined multiple times using a new slag. In this study, an initial slag composition of 45CaO-45SiO2-10Al2O3 (wt per cent) was utilised. Using this technique, boron level in the silicon was expected to be gradually lowered because the new slag will always have more capacity to reach the equilibrium distribution coefficient (LB = (ppmwB)slag/(ppmwB)Si). The current study was carried out through combined thermodynamic calculations (using FactSage™ ver 8.2, by Thermfact Ltd, thermochemical package) and high-temperature experimentation. The thermodynamic calculations were carried out for reactions at 1500, 1550, and 1600°C for three different scenarios: 1. Single stage refining with varied slag to Si ratio. 2. Multistage refining with slag to Si ratio of 1:1. 3. Multistage refining with slag to Si ratio of 2:1. The multistage experimental work was carried out at 1550°C under inert gas atmosphere each time for 2 hrs, with slag to Si ratio of 2:1. The simulation results indicate that the boron distribution coefficient stay essentially constant with varying slag to Si ratio and temperature, around 1.8 to 2, and the experimental results measured LB in the same range, between 1.5 and 2.5. By harnessing this feature, the simulation showed that boron can be removed by approximately 78 per cent in each stage. The experimental result confirmed that the boron concentration in the silicon was reduced by a total of 97.8 per cent from its initial value using four stages of slag treatment, from initial 270 ppmw down to 6 ppmw.

Aug 21, 2024

By James C. Norman

The boron review arrived too late to appear in the June issue. The US was the world's second largest producer and the largest consumer of boron compounds during 1990. Boron mineral concentrate and chemical production in the US totaled 1.13 Mt (1.2 million st), including 565 kt (662,800 st) of boric oxide (B2O3) in 1990, according to US Bureau of Mines estimates. Total value amounted to $404 million. This was slightly higher in production than 1989 but down in value, reflecting a softening in boron product prices. Total world production of boron mineral concentrate and chemical tonnage in 1990 was estimated at 3 Mt (3.3 million st), which corresponds to about 1.3 Mt (1.3 million st) of BO,. World production in 1990 was about the same as in 1989.

Jan 1, 1991

By J. C. Norman

The boron review arrived too late to appear in the June issue. The United States was the world's second largest producer and the largest consumer of boron compounds during 1991. According to the US Bureau of Mines, boron mineral concentrate and chemical production in the US totaled about 1.1 Mt (1.2 million st), yielding about 608 kt (670,000 st) of BO, in 1991. Total estimated value was $440 million. That level of production was equal to 1990 revised production figures. Value was greater by $37 million, however, reflecting a strengthening of boron product prices. The US continued to supply essentially all its own boron while maintaining a strong position as a source to foreign markets of sodium borate products and boric acid. Domestic employment in the mining and beneficiation of boron products in 1991 remained at 1100 people, about the same level as in 1989. The Bureau of Mines estimated total world production of boron in 1991 - mineral concentrate and chemical - at about 2.9 Mt (3.2 million st). That corresponds to about 1.2 Mt (1.3 million st) of BO ,. World production in 1991 was about equal to revised 1990 levels. US production Mines and processing operations in southern California were the only domestic sources of boron mineral concentrates and chemicals in 1991. US producers, in order of quantity of production, were US Borax and Chemical Corp., North American Chemical Co., and American Borate Co.

Jan 1, 1992

By J. C. Norman

The boron review did not arrive in time for publication in the June issue. The United States was the world's largest producer and consumer of boron compounds during 1992. The US Bureau of Mines estimated that boron mineral concentrate and chemical production in the United States totaled 1Mt (1.1 million st) in 1992, yielding 521 kt (574,000 st) of B203 for a total estimated value of $333 million. That was about 20% less than 1991 revised production figures, and less in value by $107 million. The United States continues to provide essentially all of its own boron supply while maintaining a strong position as a source of sodium borate products and boric acid to foreign markets. Domestic employment in the mining and beneficiation of boron products in 1992 was about 900 people, the same as in 1991. In 1988, 1250 people worked in the boron industry. The Bureau estimated that total world production of boron in 1992 was about 3 Mt (3.3 million st), or about 1.2 Mt (1.3 million st)of B2O3. World production in 1992 was about equal to revised 1991 levels. US production Mines and processing operations in southern California were the only domestic sources of boron mineral concentrates and chemicals. US producers, in order of quantity of production, included:

Jan 1, 1993

By J. C. Norman

The boron review arrived too late for the June issue. The United States was the world's largest producer and consumer of boron compounds during 1993. Boron mineral concentrate and chemical production in the United States totaled an estimated 958 kt (1.05 million st), yielding 526 kt (580,000 st) of B203, according to the US Bureau of Mines. Estimated value was $322 million. This level of production was about 5% less than 1992 revised production figures. The United States continued to provide essentially all its own boron while maintaining a strong position as a source of sodium borate products and boric acid to foreign markets. Domestic employment in the mining and beneficiation of boron products in 1993 was 900 people, about the same as in 1992. That was down from 1988 levels of 1250 people. Total world production of boron in 1993 was about 2.5 Mt (2.75 million st), yielding about 1.2 Mt (1.3 million st) of B203. World production in 1993 was about equal to revised 1992 levels. Production United States In 1993, mines and processing operations in southern California were the only domestic sources of boron mineral concentrates and chemicals. Domestic producers, in order of quantity of production, were: • US Borax and Chemical Corp., which operates an open pit kernite and tincal mine at Boron, CA, producing boric acid and borax products, • North American Chemical Co., which produces boric acid and borax products as coproducts from chemical operations at Searles Lake, CA and • American Borate Co., which produced small amounts of colemanite and shipped from inventories from its operation in Death Valley, CA.

Jan 1, 1994

By J. C. Norman

The United States was the world's largest producer and consumer of boron compounds during 1994. According to US Bureau of Mines (USBM) estimates, boron mineral concentrate and chemical production in the United States totaled about 1.05 Mt (1.15 million st), yielding 560 kt (617,000 st) of B203, for a total estimated value of $370 million. This production level was about 2% less than 1993 revised figures. The United States continued to provide nearly all of its own boron supply while maintaining a strong position as a source of sodium borate products and boric acid for export. Domestic employment in the mining and beneficiation of boron products during 1994 was 900 people, about the same as in 1993. USBM estimated total world production of boron of about 2.3 Mt (2.5 million st), yielding 1.1 Mt (1.2 million st) of B203. World production during 1994 was about the same as during 1993. USBM estimates US reserves to be about 210 Mt (231 million st) of ore and world reserves to be about 630 Mt (694 million st) of ore.

Jan 1, 1995

By J. C. Norman

The United States was the world’s largest producer and consumer of boron compounds during 1995. According to estimates from the US Geological Survey(USGS), boron mineral concentrate and chemical production in the United States totaled an estimated 1.1 Mt(1.2 million st) yielding 602 kt (663,000 st) of B2O3 for an estimated value of $462 million. This level of production exceeded 1994 revised production figures by about 9%. The United States continued to provide nearly all its own boron supply while maintaining a strong position as a source of sodium borate products and boric acid to foreign markets. During 1995, about 900 people worked in domestic boron mines and plants, about the same as in1994. USGS estimated total world production of boron during 1995 to be about 3 Mt (3.3 million st), yielding about 1.6 Mt (1.8 million st) of B2O3. World production in 1995 was about equal to revised 1994 levels.

Jan 1, 1996

By T. PH. D. Egleston

THE Boston and Colorado Smelting Works are situated in the town of Black Hawk, Gilpin County, Colorado, on the Clear Creek Narrow Gauge Railway, 55 miles from Denver, in the Rocky Mountains, at an altitude of 7800 feet. It was one of the first works erected for the metallurgical treatment of gold ores, and the only one established in Colorado on a large scale which has been uniformly successful. Both gold and silver ores are treated, and gold, silver, and copper produced. The lead is not separated from the ores nor paid for, if it exists, and is entirely lost in the residues. The works were planned and built by Professor Hill, formerly Professor of Chemistry in Brown University, Providence, R. I., and is still managed by him, assisted by Mr. Richard Pearce, formerly professor in the School of Mines at Truro, England. They are very advantageously situated with regard to the ore-producing regions, having Boulder County on the north, which produces, besides ordinary gold ores, a series of tellurium minerals, such as altaite, sylvanite, and hessite, which are very rich in gold and silver. They are associated with copper and iron pyrites, blende, galena, and the carbonate and oxides of iron. Gilpin County itself produces for the most part the pyrites of iron and copper rich in gold, with a small quantity of galena and blende, which is rich in silver. In * By consent of the council of the Institute, this paper was first published in London Engineering, from which the engravings are here reproduced.

Jan 1, 1876

By J. Robert Van Peli

IT was a strange but highly fruitful marriage-that union of hardy explorers, seeking the rich treasures of copper in the Lake Superior wilderness, with Boston's aristocracy of brains, capital, and enterprise. This historic wedlock, which has continued happily to the present day, was the means by which the wealth of Lake Superior's copper was won for the use and benefit of an expanding America. One branch of this family tree, the western branch, begins with prehistoric Indian miners, embraces the early French explorers of the Upper Lakes, and finally includes the British and American pioneers who reduced the vague rumors of copper to known fact and actually began the mining of copper in the wilderness. The other branch, the New England line, begins

Jan 1, 1948

Jan 1, 1883