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By M. M. Wong, J. E. Klosterman

Scrap beryllium chips ( nominally 96 to 97 percent Be ) were electrore fined in a prototype cell with 408 lb of electrolyte composed of 52.4 mole - percent LiCl , 36.3 mole - percent KC1 , and 11.3 mole - percent BeCl2 . The cell temperature was 500 ° C. In a typical 10-3 /4 - hour deposition cycle , 0.415 pound of metal was produced ; the metal contained impurities in parts per million as follows : C , 700 ; 0 , 610 ; Al , 34 ; Ca , 32 ; Cu , 20 ; Fe , 25 ; Mg , 9 ; and Mn , 23 . Operation of the prototype cell for 2 years demonstrated that adapting the electrorefining process to an enlarged scale of operation presented few difficulties in mechanical functions , maintenance of optimum operating conditions , and control of product purity . After the spent anode feed was leached in a 5 - percent nitric acid solution and the fine - sized particles were removed , it was recycled in some tests . The metal produced was somewhat higher in impurities than metal from the fresh scrap chips .

Jan 1, 1964

By A. W. Henderson

This investigation was performed to develop chlorination methods for extracting tungsten from scheelite and from an ore concentrate containing a mixture of scheelite and wolframite. On a laboratory scale with proper temperature control using elemental chlorine, over 90 percent extraction of tungsten is achieved. Carbon and sulfur dioxide were studied as reducing agents. The effects of salts such as calcium fluoride and sodium chloride were studied as additives to increase extraction and to reduce impurities in the volatile tungsten chloride product. Sodium chloride reacts with ferric chloride to form a nonvolatile double salt; whereas the chlorides and oxychlorides of tungsten are volatile and consequently condense free of iron. Separation of tungsten from molybdenum from an equal molar mixture was successful by fractionally distilling the oxygen-free chlorides and by selectively condensing the oxychlorides. Yields of 60 and 80 percent, respectively, were achieved for separating the less volatile tungsten chlorides containing less than 0.5 percent molybdenum.

Jan 1, 1965

By Charles W. Huggins

To determine the nahcolite and dawsonite content in oil shales, the Bureau of Mines compared X-ray diffraction, infrared spectroscopy, thermal methods, and a previously published method by Smith and Young based on the selective solubility of sodium compounds. The Smith and Young method and a new method based on the weight of carbon dioxide produced by thermal decomposition are recommended for determining nahcolite. X-ray diffraction and the Smith and Young method are recommended for determining dawsonite. X-ray diffraction, infrared spectroscopy, and differential thermal analysis were useful for identifying other minerals in the samples.

Jan 1, 1973

By E. A. Sondreal

The Bureau of Mines investigated the use of lignite char for producing carbon disulfide; CS2 production rates were as high as when wood charcoal was used as raw material. The maximum space velocity for CS2 produced in the bench-scale study was 9,280 hour-1, reacting sulfur and lignite char at 792° C. The reaction temperature and the temperature at which the char was carbonized were the two most important factors in determining CS2 production rates. Increasing the carbonization temperature in nitrogen from 400° to 900° C advanced the temperature at which carbon disulfide was first produced from 550° to 850° C. The average activation energy for reacting chars with sulfur was 44,000 cal/g mole. The reaction was first order with respect to the partial pressure of sulfur. Increasing the rate of sulfur admission caused a decrease in rate of production at otherwise similar conditions. Rates were not affected by either char size or sodium carbonate catalysis. High space velocities at moderate temperatures using inexpensive lignite chars could offer an economic advantage in the manufacture of carbon disulfide provided that yields were attractive.

Jan 1, 1967

By M. P. Dalton

This paper which describes the milling practice at the Morning concentrator of the Federal Mining and Smelting Co., Mullan, Idaho, is one of a series being prepared by the Bureau of Mines. ACKNOWLEDGMENT The author wishes to acknowledge the assistance given by H. G. Washburn, general manager of the Federal Mining and Smelting Co., and by C. S. Price, assistant mill superintendent, in the preparation of this paper.

Jan 1, 1932

By Frank E. Federspiel

In 1992, the Bureau of Mines conducted a mineral resource investigation of the 78,000-acre Garns Mountain study area in southeastern Idaho. The area had been proposed for Wilderness. It is underlain by Paleozoic to Mesozoic-age sedimentary rocks about 11,000 feet thick. Rocks have been faulted, offset, and folded as part of the northerly-trending Idaho-Wyoming Overthrust Belt. Study area mineral occurrences are: phosphate in the Permian Phosphoria Formation; coal in the Cretaceous Frontier end Bear River Formations; and uranium in carbonaceous and phosphate-bearing shales and coal of these formations. Four zones of phosphate are estimated to contain about 528 mitt ion tons of rock with over 10% P205; samples of phosphate-rich rock also contained as much as 3950 ppm chromium, 3280 ppm vanadium, 23 ppm gallium, and 5540 ppm zinc. Fragments of poor-quality coal and carbonaceous shale were found in the area; coal was mined near the northeast border. Uranium content up to 0.016% U3O8 is in carbon-rich shales. Oil and gas were drilled for, with minimal success, in folded sedimentary rocks (frontier and Nugget Sandstone) in the Horseshoe anticline, near the east border. Examined workings included 12 dozer cuts, 4 trenches, 2 prospect pits, and 2 caved adits. No production is known, and no leases or claims are held for the area.

Jan 1, 1992

By Everett A. Sondreal

Data are presented on the characteristics of lignites with emphasis on the composition and fusion properties of the ash. Differences in the analyses of commercial-grade lignites are related primarily to variations in moisture and ash contents. Lignite ash is generally characterized by high concentra¬tions of alkaline earth oxides and a greater tendency for retention of sulfur in the ash than higher-rank coals. Composition of ash varies significantly within and between mines. The differences within mines are significant for short distances and may be eliminated under certain circumstances by normal mixing occurring during mining. The sulfur in lignite averages 0.6 percent and is found primarily in the organic or pyritic forms with only a trace of the sulfate. During the stan¬dard laboratory asking procedures, from 60 to 100 percent of the original sul¬fur is retained in the lignite ash. Trace elements, such as uranium and germanium, in the ash from commercial¬-grade lignites are present in low concentrations, but others, primarily copper and silver, are present in specific samples in concentrations approaching those found in some commercial ores.

Jan 1, 1968

By Steven J. Schatzel

Prior research has suggested that the source of respirable silica dust in underground coal mines is typically the immediate top or bottom lithology adjacent to the mined seam, not mineral matter bound within the mined coal bed. Geochemical analyses were applied in an effort to identify the specific source rock of respirable quartz dust in coal mines. The analyses also demonstrate the compositional changes that take place in the generation of the respirable dust fraction from parent rock material. All six mine sites were mining coal with relatively low mineral matter content, although two mines were operating in the Fire Clay coal bed which contains a persistent tonstein. Interpretations of Ca, Mg, Mn, Na, and K concentrations strongly suggest that the top strata above the mined seam is the primary source of mineral dust produced during mining. One site indicates a mixed or bottom source, possibly due to site specific conditions. Respirable dust compositional analyses suggest a direct relationship between the quantity of mineral Si and the quantity of quartz Si. A similar relationship was not found in either the top or bottom rocks adjacent to the mined seam. An apparent loss of elemental Al was noted in the respirable dust fraction when compared to potential parent rock sources. Elemental Al is present in top and bottom rock strata within illite, kaolinite, feldspar, and chlorite. A possible explanation for loss of Al in the respirable dust samples is the removal of clays and possibly chlorite minerals. It is expected that removal of this portion of the Al bearing mineral matter occurs during rock abrasion and dust transport prior to dust capture on the samplers.

Jan 1, 2009

By K. K. Kelley

This report contains heat-content values for hexagonal crystalline germanium dioxide between 298.15° and 1,350° K., and for germanium dioxide glass between 298.15° and 1,800° K. experimentally determined by the Federal Bureau of Mines. No similar data for these substances are to be found in the literature. The heat-content and corresponding entropy-increment data are presented both in tabular form and by equations. Free energy of formation values are estimated for germanium dioxide glass at 298.15° and 1,800° K.

Jan 1, 1961

By S. P. Kinney, P. H. Royster, T. L. Joseph

An investigation of the production of iron in the blast furnace is obviously not an easy subject for research . Enough is known of the mechanical , thermal and chemical conditions existing inside the furnace to say certainly that they are complicated. Furnace operators have found that the process is sensitive to a number of known and to many unknown operating conditions . In order to form any conclusions of value , it seems necessary to collect a large amount of data taken with considerable care and accuracy. These facts make a blast furnace research difficult but not impossible . The most serious obstacle in attacking the problem comes from the fact that it is useless in the design and operation of the blast furnace to use the method of " trial and error , which has proved valuable in so many other industrial problems . The variables are so interrelated and are so dependent one on the other that the number of experimental combinations to be tried is enormous . There are certainly not less than twenty factors in furnace operation and design that are known to influence the results . This is apparent if it is remembered that a phrase like " size and shape of the furnace" includes height of the furnace , height , diameter and angle of the bosh , inwall batter , stockline diameter , and furnace volume ; and that a phrase like " chemical and physical properties of the fuels charged " includes size and shape of the lumps , density, porosity and strength of the coke , in addition to its chemical analysis . Let us suppose that we need choose for each of twenty factors one of two values , for example , suppose we must say only that the furnace shall be " tall " or " short , " that the bosh angle shall be " flat " OF "steep , that the ore shall be " coarse " or " fine , " or that the blast has to be "hot" or " cold , " the number of resulting combinations is more than one million . In putting twenty pennies on the table , either heads up or tails up, the number of permutations possible is the twentieth power of two , slightly more than one million. It is obvious , therefore , that some sort of mathematical relationship , a set of rules of thumb , laws , curves or the like , are needed . Whether the relationships , curves or formulas are derived from experiment , from theory, or from mere guess -work, makes no difference provided they agree with the known facts . If they do not agree with known facts , they are worthless no matter what their origin or how weighty the " authority" vouching for them. Few such relationships have appeared in blast- furnace literature , and it may be doubted whether such formulas can be discovered .

Sep 1, 1923

By William A. Beck

"The Piedmont Manganese Belt extends from Taliferro County, Georgia, 70 miles in a northeasterly direction through Greenwood County, South Carolina, and conforms with the trend of the Piedmont Province. The total area of the belt is reported to be about 1,000 square miles, and the maximum-width is about 24 miles.Manganese has been known to exist in the belt since 1845. M. Tuomey mentioned a deposit in the Edgefield district on Hard Labor Creek in South Carolina in a report on the geology of South Carolina published in 1848.Ore was first mined about the time of the first World War, when the Colley mine, near Lincolnton, Ga., was. Opened. The only operation in the area at present is that of the Abernathy & Kehaya Mining Co., at McCormick, S. C.The geographical position of the belt is from west longitude 82° 57’, north latitude 33° 39' to west longitude 82° 06', north latitude 34° 08'. The towns of Washington and Lincolnton, Ga., and McCormick and Greenwood, S. C., are in or near the belt.An exploratory project of the Bureau of Mines was started on the McCormick, S. C., deposit in April 1944, and trenching, test pitting, and hand-auger drilling-were done on a small scale until early in October 1944. (Fig. 1.) In November 1944 work was begun on a property 12 miles north of McCormick, known as Parsons Mountain, which is leased to M. H. McKnight by the United States Forest Service. From March 15 to March 24, 1945, work was done on the property of Mrs. H. B. Ross, which is known as the Morgan farm.The Abernathy & Kehaya manganese mine contains what is locally known as the Dorn gold mine; mineral rights on the property were owned by M. G. & J. J. Dorn, Inc."

Apr 1, 1946

By H. Kenworthy

Small batches of fluorspar flotation concentrates were made into nodules and pellets on a laboratory scale. Several of these were rated acceptable by laboratory evaluation methods. The most satisfactory pellets were produced by mixing fluorspar with about 12.5 percent of water, by weight, and 4 percent of organic binders. These binders) for the most part) originated from petroleum and wood-pulp industries. They were generally difficult to handle and were not easily incorporated with the fluorspars tested. Most of them seemed to have an aversion for damp fluorspar and had to be forcibly mixed with the fluorspar; which was then formed into pellets by pressure. Substitution of fuel oil in varying amounts in the binders enhanced the mixing and penetrating qualities of these binders but at the same tire tended to make the pellets more porous. Tall oils performed the same function to a lesser degree and usually decreased the water absorbency of the finished pellets. Heat-treating temperatures to set up these binders were moderate -about 5000 F. for 30 to 50 minutes was usually enough for both drying and heat treating. Nodules made with 1-1/2 to 2 percent of bentonite as a binder were easily mixed and formed. They required a high degree of heat (about 1,500° F.) to develop their strength and were quite water-absorbent when finished. Two fluorspars were examined for weight and fluorite loss after heat treatment at similar temperatures. Both showed a definite wej.ght and analytical loss of fluorite. Bentonite was used also as a binder to successfully nodulize finely ground oxides of iron, manganese, and nickel.

Jan 1, 1951

By Raghoottma S. Pandurangi, Mohindar S. Seehra

"The interaction of amorphous 1ilica particles with several hydrogen bonding agents (H2O, C2H5OH, C7H2NO) was investigated by monitoring the changes in the bulk and surface IR vibrational modes of silica using photoacoustic spectroscopy. It is argued that the intensity of the silanol band at 3747 cm-1 provides (an inverse) quantitative measure of the interaction or surface groups, along with the shift in the broad hydroxyl band, the interaction following the order C7H2NO > C2H5OH > H2O. Index Headings: Silica; Surface vibrational modes; Photoacoustic spectroscopy; Hydrogen bonding agents.INTRODUCTIONThe use of m spectroscopy to study the adsorption on solid surfaces is well documented in the literature.1 2 For example, hydroxylation of a clean silica surface results in the formation of the free silanol group Si-OH, with a sharp IR band near 3747 cm-1• Further hydroxylation produces a broad band near 3500 cm-1, which is believed to result from various hydrogen-bonded silanol bands leading to a multilayered surface structure of few nm.3-5 Earlier studies had indicated a relationship between the surface silanol band and various chemical activities of silica such as cytotoxicity, 7- 9 catalysis, 10-12 and others.13 Recent studies from our group14-in which the intensity of the silanol band and cytotoxicity of silica, heat-treated at various temperatures up to 1095°C, were investigated have provided a strong correlation between cytotoxicity and intensity of the silanol band.Coating of silica by PVPNO (polyvinyl-2-pyridine N-oxide with the empirical formula C7H8NO), a strong hydrogen bonding agent, is known to reduce the cytotoxicity of silica, presumably by chemically blocking the silanol groups from phospholipids.15 This interaction of the hydrogen bonding agents with the silica can be studied by m spectroscopy, and Knozinger16 and Rouxlet and Semples11 have used transmission m spectroscopy to study the effect of various chemicals on the surface IR modes of silica. However, one of the major disadvantages of transmission IR spectroscopy is that the sample preparation (grinding and mixing with KBr and pelletizing) usually distorts the surface modes (see, e.g., Ref. 14) and there is always a doubt about the effect of the sample preparation on the measured properties. In recent years, photoacoustic (PA) spectroscopy has become the technique of choice for studying the IR spectra of samples in their natural state, since no sample preparation is necessary.18•19 Moreover, according to a recent paper, 20 the relative intensity of the surface modes in PA spectroscopy of silica particles is much higher than that in transmission FT-IR spectroscopy. Consequently PA spectroscopy is ideal for studying the surface chemistry. In this work, we have used PA spectroscopy to investigate the interaction of three hydrogen bonding agents (C7H8NO, C2H50H, and H20) with the silica surface by monitoring changes in the surface m modes. Our results show that the surface IR modes get perturbed to a larger extent than the bulk IR modes in interaction with the hydrogen bonding agents. Moreover, whereas in the earlier studies, the shift of the broad silanol band near 3500 cm-1 was used as a measure of the interaction with hydrogen bonding agents,16•17 here we show that the relative decrease in the intensity of the sharp silanol band near 3747 cm-1 also serves as a quantitative parameter for the relative surface coverage and surface modification. Details of this work are given below."

Jan 1, 1990

By H. E. Powell

The magnetic susceptibilities of 57 minerals containing titanium, zirconium, vanadium, columbium, tantalum, chromium, molybdenum, and tungsten were determined. The source and petrographic analysis of each sample are given. Included are values for isomorphous series of minerals showing wide ranges of composition and for a few high-purity synthetic minerals.

Jan 1, 1968

By Peter H. Toepfer

This report presents the factual data obtained by the Bureau of Mines during diamond-drilling investigation of the Sunset copper deposit in the Index mining district, Snohomish County, Wash. The Sunset mine, first produced copper ore in 1902, but its main period of activity was from 1923 through 1930, The mine has produced 263,500 tons of ore, from which 1,500 ounces of gold, 156,000 ounces of silver, and 12,912,000 bounds of copper-were recovered. The mine has, been idle since 1946

Jan 1, 1953

By James P. McGee

Preliminary calculations show an economic advantage in using nuclear energy to supply the endothermic heat required for gasifying coal. It should be noted that the various assumptions used in preparing these calculations must undergo further evaluation through additional engineering design and research. The proposed system for gasification is the indirect process cycle with helium heated in a nuclear reactor and passed through an exchanger-type gasifier for the reaction of coal and steam to form CO (carbon monoxide) and H2 (hydrogen gas).

Jan 1, 1960

By Paul Hatmaker

Pumice and pumicite are siliceous volcanic substances quite similar in chemical composition , but somewhat different in physical properties , manner of formation , and mode of occurrence . Production in the United States has increased from 23,271 tons valued at $ 94,943 in 1910 , to 56,843 tons valued at $336,099 in 1930. Both pumice and pumicite are included in these figures as it has been impractical to collect statistical data on the separate commodities .

Mar 1, 1932

By J. G. Kirby, F. S. LOTT

The mmber of petroleum refineries in the United States decreased during 1949 from 375 to 367 while the total crude-oil charging capacity of refineries continued to increase. A gain in the through-put capacity of 257,305 barrels daily raised the total to a new high level 6,696,300 as of January 1, 1950. The capacity of the average refinery to process crude-oil increased during 1949 from 17,171 barrels daily to 18,246. The four coastal refinery districts accounted for 178,900 barrels or 70 percent of the total capacity increase and the Illinois-Indiana- Kentucky district 57,950 barrels, or 23 percent. Slight declines in capacity were reported in the Texas Inland and the Arkansas-Louisiana Inland districts. The capacity building on January 1, 1950, 145,600 barrels daily, was less than half the amount under construction a year earlier. Most of the new construction involved enlargement of existing refineries and was confined to the East Coast and Indiana-Illinois-Kentucky districts. Two new refineries, however, were under construction, one in Oklahoma and the other in Texas. The shut-down capacity increased for the first time since 1946, and the 473,302 barrels daily reported on January 1, 1950, was the largest recorded since January 1, 1938. The only refining district showing a decline in the shut-down capacity was the Appalachian No. 2 district. The largest increases were reported in the Texas Gulf, Indiana-Illinois- Kentucky, California, and East Coast districts. The operating ratio of the petroleum refining industry, as indicated by dividing the January 1950 runs to stills of 5,483,000 barrels daily by the total installed capacity January 1, 1950, was 81.9 percent, compared with a ratio of 87.8 percent at the beginning of 1949.

Aug 1, 1950

By R. E. Siemens

The Bureau of Mines sought to correlate the variation of structure-sensitive superconducting properties with microstructure in selected Cb-Hf alloys and to compare the experimental results with those predicted by the GLAG theory. Alloys in wire and rod form were evaluated by critical temperature, critical current, magnetization, resistivity measurements, and optical and electron microscopy. In the absence of an external magnetic field, the current carrying capacity of columbium was greatly reduced with addition of up to 85 wt pct Hf, but a large increase in Ic occurred for Cb-90 wt pct Hf. Favorable Ic-H behavior was observed in cold-drawn alloys containing 25 and 57 wt pct Hf. Correspondingly, a maximum in Tc occurred at 10-25 and 90 wt pct Hf. Four- or five-hour heat treatment at 600° C resulted in maximum Ic values and maximum hysteresis in magnetization. Dislocation pileup, polygonization, and fine precipitates, responsible for flux pinning, are listed in order of their effectiveness as pinning sites. Sites having an average separation of 1,500 to 3,000 A and a diameter of 1,000 A or less were most effective in influencing Ic-H and M-H behavior. The resistive critical fields increased smoothly to a maximum of 80 k0e between 60 and 65 wt pct Hf. Highfield, mixed state, reversible paramagnetism was observed in some alloys; however, the GLAG theory was in good agreement with experimental results for the majority of the composition range studied.

Jan 1, 1969

By William D. Mayercheck

The U.S. Bureau of Mines is conducting research aimed at providing technology for a low-cost, high-recovery, environmentally acceptable mining system to recover the vast thin-seam coal reserves existing in the mountainous areas of the Appalachian region in the Eastern United States. As part of this research, the Bureau is evaluating new techniques to address these coal resources. This report summarizes the results of a worldwide technical search on thin-seam coal mining, the formulation of various methodologies for mining mountaintop thin seams, and the implementation and status of a physical model test program to validate and further develop the most promising concept-the "roof-fall-tolerant" mining system.

Jan 1, 1990