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By Glenn L. Cook

Correlations between mass spectra and molecular structures of 186 organic sulfur compounds are discussed. The olefinic ions, the alkyl ions, the CnE2n+1 ions, the m/e 61 ions, and the m/e 35 ions in the spectra of thiols are related to molecular structure. In the spectra of sulfides, the olefinic ions, the m/e 61 ions, the m/e 35 ions, the CnH2n+1S+ ions, and the CnH2n+1SH+ ions are correlated with molecular structure. For disu1fides, the correlations relate HSSF+& and RSSH+ ions to molecular structure. Base peaks of alkylthiophenes are correlated to their molecular structures. Some unimolecular reactions of sulfur compounds in the mass spectrometer are considered. A cyclic intermediate is suggested for the reaction which produces m/e 47, CH3S+, and m/e 48, CH4S+, ions in the spectra of sulfides. An expanded ring is suggested as a possible intermediate in the reactions of thiophenes. Heats of formation of sulfur-containing ions and their appearance potentials are presented in tabular form. Ionization potentials for sulfur-containing radicals and molecules are also given. Discussion of the spectra, tabulated in the appendixes, provides an insight into the relationship of the molecular structure of a compound to the mass-to-charge ratios and the intensities of the ions in its mass spectrum. Correlations of the mass spectra with molecular structures are empirically developed by observing regularities in the spectra of the reference compounds. Correlations extend the usefulness of mass spectra because they can be employed to determine the molecular structure of an unknown compound.

Jan 1, 1965

By A. E. Lindquist

This Bureau of Mines publication identifies areas having sufficient coal reserves to support synthetic natural gas (SNG) development and summarizes those areas having the highest potential. Capital requirements, mining and coal cost factors, water availability, and coal-quality data pertinent to SNG production are presented. Evaluation of individual coal reserve blocks was based upon coal and water requirements of the Bureau of Mines Synthane coal gasification process.

Jan 1, 1977

By Emory Smith

The preface of the United States Bureau of Mines Manual of First Aid Instruction contains the following paragraphs: One of the most important inquiries that Congress has authorized the Bureau of Mines to conduct relates to health condi- tions among those engaged in the mineral industries. Investigations made early with a view to bettering these conditions demonstrated the need of prompt care of injured miners, as, under the difficulties inherent to mining and other mineral industries; wounds seemingly unimportant, if not treated promptly, may become infected and possibly cause permanent crippling or even death of the porach. In the past many seriously injured persons have been treated by fellow workers ignorant of approved means of treatment and transportation and have been handled in such a manner as to cause suffering and to accentuate injuries to such a degree as to bring about permanent disablement. Accordingly, the need of general instruction in first aid became apparent. It must be recognized that the conditions in and about the mines, mills, smelters, quarries, oil fields, etc., usually present difficulties not found in large industrial centers where experienced surgeons are available and hospitals close at hand. Many mines are isolated and, when an accident occurs several miles underground, there may be a serious lapse of time before the injured person can be brought to the surface and taken to the hospital or given attention by a sur- geon who may have to come a long distance. Under such conditions it has been frequently demonstrated that, if effective first aid is not given, the injured person may die or become permanently crippled... First-aid instruction has been found to be an excellent aid3in pre- venting accidents. In addition to the immediate relief of injured persons, it has been found that most persons while in the act of practicing dressings for

Apr 1, 1931

By A. E. Petersen

To reduce U.S. dependence on imports of titanium, the U.S. Bureau of Mines has investigated the recovery of titanium from perovskite (CaTi03). Domestic perovskite deposits represent a significant, but untapped, titanium resource. An acid sulfation method was developed that will extract about 97 pct of the titanium and the columbium and 70 to 90 pct of the rare-earth byproducts from perovskite concentrates. A flow-sheet for recovering titanium as pigment-grade titanium dioxide (Ti02) is discussed. Test work performed in developing each unit operation is described. The first three unit operations have been demonstrated using laboratory-scale continuous methods of operation: acid sulfation of perovskite concentrates, leaching sulfation residue to dissolve metal values, and precipitation of titanium oxysulfate monohydrate (TiOS04?HP) from the resulting leach flltrate. Batch testing of other unit operations was performed: TiOS04?H20 redissolution and iron reduction, precipitation of Ti02 by hydrolysis, and regenerating recoverable acid with rare-earth byproduct recovery. Cost evaluation results are provided, indicating that processing perovskite concentrates by acid sulfation may be an economically viable means of producing Ti02.

Jan 1, 2010

By Michael T. Nigbor

This Bureau of Mines publication identifies the significant environmental issues associated with the potential development of strategic and critical minerals in the Stillwater Complex, MT. The Stillwater Complex contains deposits of Cr, platinum-group metals (PGM), and Ni. Issues that must be addressed prior to minerals development include the effects mining, milling, and smelting will have on the land, water, and air, and methods of minimizing the environmental impacts.

Jan 1, 1985

By J. W. Thompson

A mining company for a period of 12 years bad been selling its ore to a certain smelting company for the purpose of obtaining a continuous and steady market for its ore and for the purpose on the part of the smelting company of obtaining a continuous and steady supply of ore for smelting; an agreement was entered into by which the mining company agreed to eell and the smelting company agreed to purcshase at ruling prices all the ore produced by the mining company of certain' stated grades, and to this end the mining company agreed to actively operate its mines. It is no longer the rule that a suit will not lie for the specific performance of a contract relating to personal property ; but the question for determination in such a case is whether the complainant has a plain, speedy and adequate and complete remedy at law, and if he has no such remedy, specific performance will be granted. In an action by a smelting company for the specific performance of a contract of sale it appeared that the ore produced by the mining company bad a peculiar value for smelt. i.ng purposes and was not readily obtainable elsewhere, and it would be practically impossible to measure the value for determining the loss the complainant would sustain· if the smelting company were not ,able ,to obtain the ore under the contract. It is comparatively simple for a court of equity to enforce the agreement as it pertains to the normal product of the mine and there is no plausible reason why a court may not require a performance on the part of the mining company where the mining company obligated it:Belf to operate all its mines. There is no delicate or complex condition involved in the production or delivery of the ore 'or in obtaining_ the stipulated prices agreed upon, and there is nothing apparent that will necessitate supervisory· control in requiring performance on the part of the mining company. A decree for specific perfoi:m,ance would require no supervision by the court either for the operation of the mines or for ascertaining and fixing the prices the mining company is to receive for its ore.

Jan 1, 1919

By G. L. Humphrey

Although silicon carbide has been an important manufacture refractory for many years, knowledge of its thermodynamic values has been seriously lacking. In fact, some of the very properties that make it a useful substance, particularly chemical inertness, obstruct determination of its heats of formation and reaction. This paper reports the results of new measurements of the heats of combustion and formation, low-temperature heat capacity, entropy at 298.16°K., and heat-content and entropy increments between 298° and l,800°K. Two varieties of silicon carbide were studied -the common, hexagonal (type II) and cubic. The data are combined to obtain heat and free-energy-of-formation functions, which are given in tabular form. It is shown that the cubic variety is the more stable at temperatures to at least 1,800°K but, because of the inherent difficulties and errors in the heat-of-formation determinations at 298°K, it was not found possible to specify the free-energy difference accurately. The mechanism of silicon carbide formation from silica and carbon is not known and is not ascertainable from thermodynamic data. It appears improbable, however, that it can be a single-step reaction. Some reactions involving silicon monoxide gas and metallic Silicon, as possible intermediates in silicon carbide formation, are considered and shown to be thermodynamically feasible.

Jan 1, 1952

By R. L. Beatty

IN INDUSTRIAL and domestic daily life carbon monoxide is the most frequently encountered toxic gas. hazardous concentrations of carbon monoxide may be present in the vicinity of many industrial operations, such as metallurgical processes, coke ovens, and fuel- and synthesis-gas producers, and may be encountered in confined spaces, such as dwellings, garages, workshops, vehicular tunnels, and mining operations, in connection with the use of heaters, boilers, internal-combustion engines, after blasting operations, and after fires and explosions. Evaluation and control of the health and safety hazard caused by carbon monoxide depend primarily on the analytical detection of the presence of carbon monoxide and determination of its concentration in air and in various gaseous mixtures. The choice of method of analysis in any particular situation depends on such factors as required accuracy, range of concentration involved, convenience, speed of analysis required, quantity of sample available, qualitative composition of sample or atmosphere to be analyzed, and possible effects of interfering gases. Some of the methods described require only adequate understanding of operational techniques, whereas others require thorough appreciation and skill in applying the principles involved. The instruments and analytical procedures commonly used for detecting and determining carbon monoxide are described in detail, and reference is made to more specialized methods:

Jan 1, 1955

By J. C. Gerdeen

A new analytical model for the shear stiffness at a joint of the fully-grouted resin roofbolt is developed using the Theory of Elasticity and an analogy to a beam on an elastic foundation, Gerdeen [2]. The model developed in this study treats the elastic foundation modulus of the resin as being composed of both an elastic rock and an elastic resin. All previous attempts have neglected the elasticity of the rock and treated only the resin. A three dimensional finite element model of the bolt-resin-rock system is developed also and comparisons are made between the predictions made by it and the analytical solution. It is found that the agreement between the two representations ranges between 1.2% and 10.5%, with the greater differences being observed for systems of very large or very small bolt diameters and resin annulus thicknesses. Since such configurations are not the rule in practice parameter studies are performed using the analytical solution with the finite element solution being used as a check. For a 0.75 in. bolt, a resin annulus thickness of 0.1375 in., a resin with E = 7 x 105 psi and -1) = 0.210, and a rock of modulus E = 6.8 x 106 psi and V = 0.159 the shear stiffness is found to be 1.220 x 106 lb,/in, from the analytical solution and 1.245 x 106 lb,/in, from the finite element model. Applying the finite element model to the problem of the axial stiffness of the fully-grouted resin roofbolt a value of 6.002 x 106 lb./in. is obtained which proves to be at least 50% higher than any of the now existing analytical predictions.

Jan 1, 1976

By James A. Wasson

Because of the danger to life and property in a coal mine if an oil or natural gas well should be accidentally intersected during mining operations, certain precautionary measures should be carried out prior to entering previously unmined areas. The locations of all wells both at the surface and at the depth of the coalbed should be accurately determined. The condition of the well should be learned from surface observations, and more importantly, from subsurface examination by geophysical logging devices where possible. It is also desirable to learn the physical properties of the hydrocarbon-bearing rock formation and the hydrocarbon fluids. The major hazard presented by oil or natural gas wells to mining operations is that of explosion and fire due to the rapid release of gas into the mine atmosphere. Wellbore pressure, the principal index of danger, should be determined by one or more of the methods described and by a service company such as those listed in the appendix. Because of high pressures involved and the consequent hazard, much emphasis has been placed on underground storage of natural gas in areas containing minable coalbeds. Maps are shown of the principal coal producing areas and the locations of currently active gas storage reservoirs. A checklist has been included of factors to be considered when mining coal in an area where oil or gas wells exist.

Jan 1, 1973

By R. S. Lang, C. C. Merrill

The recovery of zinc from oxidized zinc minerals by the caustic soda leach and electrolytic or chemical precipitation was investigated . With the exception of willemite ( 2 ZnO • Si0₂ ) oxidized zinc minerals were readily soluble in 180 to 240 g / 1 NaOH solutions . A high- grade zinc flake was recovered electrolytically from solutions which had been treated with zinc powder to precipitate copper and lead . Solutions were recycled to the leach stage with a recovery of about 85 percent of the zinc from an ore containing 21.2 percent zinc . Electrolysis was conducted at a current density of 120 amp / ft2 with a power consumption of about 1.5 kwhr /lb zinc . Zinc was also recovered from leach solutions by dilution of the solutions , carbonation of the solution , or the addition of sulfur to boiling solutions . A dilution ratio of 5 : 1 precipitated 59 percent of the zinc in 9 days . Carbonation of the solutions precipitated the zinc as zinc oxide ( ZnO ) and solutions could be recausticized for recycling . Zinc precipitated as the sulfide with sulfur was easily filtered and washed . Approximately half of the sulfur added to solutions was lost in the form of sodium thiosulfate ( Na S₂03 ) .

Jan 1, 1965

By S. L. May

Procedures for separating columbium and tantalum have been developed by the Bureau of Mines as part of a broad research program on the utilization of low-grade ores of columbium and tantalum, Columbium and tantalum compounds of greater than 99 percent purity have been obtained by application of the solvent extraction separation system: Hydrofluoric acid-sulfuric acid-methyl iso-butyl ketone. This system is unique in that it not only separates columbium from tantalum, but also separates these two metals from other metallic impurities. The system is effective for separating the metals irrespective of the tantalum and columbium ratio of the starting materials. Investigations in which the spent feed obtained from the initial coextraction step was recycled to the system indicated that efficiency was increased, and cost was reduced without impairing product purity. Continuous tests demonstrated that this solvent extraction system could be used in large-scale equipment without loss in efficiency or in purity of products. The separation of columbium and tantalum has been difficult because of the similarity in their chemical bahavior. Many methods have been proposed for separating these two elements, but most methods either did not achieve satisfactory separation or were tedious and time consuming. The Marignac process (3, 4)4 developed in 1866 was the only method used commercially until recently. This separation procedure is based on the difference in solubility in aqueous solution of potassium tantalum fluoride and potassium columbium oxyfluoride. Current commercial practice appears to favor solvent extraction as a method for separating tantalum from columbium (1). Several efficient methods for separating columbium from tantalum by solvent extraction (2, 9, 8) were reported earlier from this laboratory.

Jan 1, 1961

By A. B. Hooker

Nineteen of the installations were on rental contracts 1.L."'1der whtch the lamps belong to the lamp company and are rented by t.½em to the mine operatj.nt; company. · The other nine installations had been upon an O\Vnership-rental basis, by which the lamps had become the property of the renter at the end of 5 years. Five of t.11e rentec installations were en a special contract calling for a guaranteed light output. These contr2.cts were based upon certified . initial performance, with the provision that the lamps be replaced whenever periodic tests of fully charged lamps, taken at random from t..h.e charge racks, showed a light output of less than 80 percent of the certified performance.

Jan 1, 1942

By Jr. Frank Parrish

This report describes the performance of 17 selected water-injection projects producing from Pennsylvanian-and Permian-age reservoirs. Illustrations depict reservoir structure and thickness, and production and injection history. A selected bibliography of publications pertaining to area oil recovery and geology is included. Tabulations of field and reservoir data reveal marked differences in the projects. Increased oil recovery resulted from injecting water in most cases; however, seven projects recovered less oil than the operators anticipated. Oil recovery by water injection ranged from 0.2 to 262 bbl per acre ft, or 0.1 to 22.5 pct of the initial stock-tank oil in place. Major reasons suggested for poor performance include: (1) Adverse directional horizontal permeability, (2) channeling of injected water through fractures or zones of high permeability, and (3) lack of containment of injected water. One 330-foot-deep project is among the first successful shallow water-floods in north Texas. Another project is the first successful Canyon sand-stone waterflood reported in the area. Previous gas injection in two Cisco sandstone projects did not prevent the reservoirs from responding favorably to waterflooding.

Jan 1, 1965

By S. C. Rhoads

The Bureau of Mines is investigating low-chromium alloy substitutes for type 304 stainless steel (type 304 SS). The purpose of the research is to reduce the chromium content in austenitic stainless steels used for corrosion-resistant applications. Nine Fe-9Cr-12Ni alloys containing additions of 0 to 5 pct Mo, 0 to 2 pct V, and 0 to 2 pct Cu were selected for evaluation. All of the experimental alloys containing 5 pct Mo and an alloy containing 2Mo-2V-2Cu possessed structure and tensile strengths similar to those of type 304 SSe Alloys containing SMo-2V and SMo-2V-2Cu had ac-ceptable welding properties as measured by the Varestraint test. Alloys containing at least 2 pct Mo had cQrrosion resistance comparable to that of type 304 SS in solutions of nitric acid, phosphoric acid, acetic acid, and citric acid. In chlorides, all the experimental alloys were susceptible to localized corrosion and stress corrosion cracking similar to that of type 304 SSe The corrosion properties were established by weight-loss tests, electrochemical polarization tests, and stress-corrosion cracking tests. An Fe-9Cr-12Ni-SMo-2V alloy and an Fe-9Cr-12Ni-SMo-2V-2Cu alloy had a combination of welding properties, tensile properties, and corrosion resistances that were most comparable to those of 304 SS.

Jan 1, 1984

By H. J. Kelly

[This investigation of the refractory properties of seven Pacific Northwest chrome ores and concentrates has shown that five of the ores and one of the concentrates are suitable for making refractories and that all may be used in combination with high-grade chromite. The specific objectives of the investigation were to determine the inherent physic al and chemical characteristics, to shapes using each of the chrome ores and concentrates, to compare the refractory qualities of the laboratory-prepared with commercial chrome refractories. As far as possible, standard tests were used as criteria.]

Jan 1, 1952

By R. A. Busch, R. R. Backer, R. W. McKibbin

The Bureau of Mines conducted laboratory tests to determine the slur- ry transport and deposition properties of coal waste. A 188.5-ft pipe test loop was constructed with instruments to measure density, flow, and power and discharge, suction, and differential pressures. A 20-ton sample of Western coal waste was crushed and screened to 100 pct minus 1/2 in. Eight loop tests using this graded waste were run at slurry densities ranging from 1.15 (25 wt-pct solids) to 1.46 (60 wt-pct sol- ids). The resultant friction-pressure gradients ranged from 0.06 to 0.24 ft of water per foot of 4-in standard steel pipe. Particle-size degradation was significant. In a typical loop test lasting 25 min, the minus 200-mesh fraction increased from 19 pct to 34 pct. Deposi- tion tests showed that without the use of a flocculant, the slurries would not dewater when left to stand for 1 week. With flocculant, ad- ditional water was released; however, the settled slurries remained thixotropic. Further testing is necessary to determine their suitabil- ity for use as backfill material in active mines.

Jan 1, 1965

By A. C. Burr

This progress report summarizes operating results on the gasification of natural lignite from five runs of the commercial-scale pilot plant at Grand Forks, N. Dak., during December 1946 and calendar years 1947 and 1948, when the plant was operated for 1,996 hours. A primary specific objective was to determine the useful life of the outer metal retort tube as it is influenced by corrosion and other factors under a wide range of operating conditions. A secondary objective was to develop the technology of production when generating gas with a high ratio of hydrogen to carbon monoxide in both the divided and continuous annuli. Results are summarized in graphs and tables that show hydrogen-carbon monoxide ratios from 2.3 to 9 at gas-production rates from 6 to 12 M cu. St. per hr. (thousand cubic feet per hour), or approximately 30 to 60 cu, ft. per square foot of heated retort-wall surface per hour. Gas yields ranged from 36 to 54 M cu, ft. per ton of natural lignite or 63 to 91 M cu. ft. per ton of moisture- and ash-free lignite, Production rates were higher in the divided annulus, but these represent the maximum capacity of the plant only at high hydrogen-carbon monoxide ratios when the high concentration of excess steam and low furnace temperature limit gas production. A ratio of 6 was the highest produced in the continuous annulus because mechanical Limitations of the auxiliary equipment prevented attainment of higher ratios. The lignite feed rate appears to influence the production rate more than any other individual operating variable. Heat balances for four periods when gas with ratios from 2.3 to 7.2 was produced with a lignite feed rate of about 325 pounds per hour suggest that the potential heat in the gas is lower at higher ratios, owing to increased heat losses in the excess steam. Heat-transfer rates through the retort tube in these four tests were between 1,500 and 3,000 B.t.u. per square foot per hour. These rates are much lower than those reached in many earlier tests, but no attempt was made to achieve maximum rates of heat transfer.

Jan 1, 1953

By Oliver Bowles

In 1943 the Bureau of Mines began a review of trends in consumption and prices of the more important nonmetallic minerals. The first report covering building materials4/ appeared in December of that year. The present paper, which deals with chemical raw materials and fertilizers, is the second of the series. The 34 years from 1910 to 1943, for which statistics are presented herein, comprise periods of uneventful peace, unparalleled prosperity, industrial depression almost to the point of stagnation, and two wars of world proportions.

Jan 1, 1945

By Bertrand L. Johnson

Before 1914 , Chile , because of her extensive resources of natural nitrates , practically monopolized the world markets for one of the leading fertilizer materials . Since nitrogen also is an important war material , constituting in fact the principal ingredient in many high-powered explosives , the World War and the widespread insistence upon national self- sufficiency for war materials brought about the development of nitrogen fixation plants in all of the larger countries . The production of by- product ammonia from gas and coke plants was likewise stimulated . As a result , Chile , even after the ocean lanes were reopened , was forced to fight for her lost markets . Since the world capacity to produce is still far in excess of annual consumption , the competition between natural and synthetic supplies has been keen and prices have fallen below pre-war levels . Chile has recently succeeded in unifying her industry , utilizing the most efficient process now in operation, and the Government is a partner in the new company that will take over all of the present producing companies . These developments place Chilean nitrate of soda , in a much more favorable position among the markets of the world . More intense competition will undoubtedly follow and , in order that those interested may become familiar with the fields upon which the nitrogen conflicts of the near future may be waged , the following general summary of the nitrogen industry has been prepared .

Jan 1, 1931