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By F. G. Schwartz

The Bureau of Mines developed a rapid and precise method for predicting storage stability of motor gasolines. This method resulted from the investigation of many analytical techniques as well as a study of fuel composition and fuel component gum-forming mechanisms. The first section of this bulletin discusses the development of the prediction test through its several phases, including revision of the standard 110° F storage test; attempts to develop a modification of the ASTM D525 induction bomb test; and the ultimate abandonment of this procedure with the adoption of the 16-hour oven test that was both precise and rapid. The second section comprises a discussion of further studies of fuel com- position, including the reactivity of certain sulfur compounds and hydrocarbons to form gum. The compositions of various gums and inorganic deposits are reported in terms of elemental analysis and spectroscopic examinations. The reactions of tetraethyllead with selected hydrocarbons are also reported.

Jan 1, 1972

By W. D. Mcmillan

Preliminary examination of the north-central Kansas clay deposits was made by the junior author during March 1943. He was accompanied by Norman Plummer, ceramist of the State Geological Survey of Kansas. Three areas Nacre selected for further investigation. Detailed field investigation by the Bureau, consisting of hand auger drilling, trenching, anti. test pitting to obtain representative samples of the clays was carried on from April to June 1943. Field .work was under the direction of Edgar B. Butte and Richard L. Schumacher, former Bureau of Mines engineers. The samples taken were analyzed at the Bureau of Mines laboratory at Rolla, Mo. Factual data obtained from the field investigation and laboratory work are set forth in this report.

Jan 1, 1948

By Douglas C. Corner

This is the first of a series of papers dealing with modern tunnel-driving methods, compiled in accordance with an outline prepared by engineers of the United States Bureau of Mines and to be published in a series of information circulars by the bureau. This series will supplement a similar and earlier series of papers dealing with mining methods and costs. ACKNOWLEDGMENTS The author desires to express hiss appreciation, of the assistance of A. C. Dennis, manager for the West Construction Co. Contractors, and Franc: E. Winsor, chief engineer for the Boston Metropolitan District mater Supply Commission who furnished much of the data and detailed description of operation appearing in the following pages. C. F, Jackson, mining engineer, United States Bureau of Mines, collaborated in the preparation and arrangement of the text.

Jan 1, 1931

By N. S. Dalal, X. Shi

"Electron spin resonance (ESR) spectroscopy has been employed to· examine the role of tetraperoxochromate( V) ions (Cro:-) and other Cr(V) species in the generation of hydroxyl (OH) radicals in the reaction of Cr(VI) with H2O 2 in biological media. In contrast to earlier suggestions, the present ESR studies using crystalline K3CrO8 as a source of Cro:- show that decomposition of Cro:- in water or in H2O 2 does not generate significant amounts of OH radicals. Addition of NADH to a solution containing Cro:- yields a Cr(V)-NADH complex, which readily reacts with H2O 2 to generate OH radicals. Similar results obtained from several other biological reductants, including vitamin B2 , indicate that a vacant coordination site on a Cr(V) complex facilitates its reaction with H2O 2 to generate ""OH radicals. We thus suggest that in biological media, reaction [3] instead of [1] or [2] is the major pathway for the OH radical generation: While the carcinogenic potential of Cr(Vl)-based compounds has been well established via epidemiologic and animal studies (1), the underlying biochemical mechanism is still not well understood (2). In a recent development, however, Kawanishi et al. (3) have reported that hydroxyl (OH)2 radicals might be the key species in the mechanism of Cr(VI) toxicity. As to the mechanism of the ""OH radical formation they suggest that Cr(VI) reacts with cellular hydrogen peroxide (H2O 2) to form the tetraperoxochromate(V) (Crog-) ions, which decompose to produce hydroxyl radicals. It was also suggested (3) that the ""OH radicals thus produced cause genotoxicity via DNA base modification and deoxyribose phosphate backbone alterations. More recently Aiyar et al. (4) reported the detection of OH radicals in the reaction of Cr(VI) with H2O 2 in biological media, including the reaction of ""OH radicals with deoxyguanosine to generate 8-hydroxydeoxyguanosine adducts, confirming that ""OH radicals could indeed play a significant role in the mechanism of Cr(VI) toxicity. However, the mechanism for the ""OH generation was not clarified, although the role of Crog- ions as possible precursors was mentioned, somewhat along the lines suggested by Kawanishi et al. (3). The possibility of the participation of Crog- in the ""OH generation has also been indicated by Sugiyama et al. (5), since they mention that vitamin B2 enhances the formation of""OH radicals in the reaction of Cr(VI) with H2O 2 because of the generation of Crog- in the reaction."

Jan 1, 1990

By S. Vennos

As a result of Synopsis 73-16 Dynadyne responded with an unsolicited proposal offering the Bureau of Mines to develop an ultra-low volume coal mine dust personal sampler. In the ensuing technical discussions the choice of a desirable volumetric rate became a focal point. While, the initial proposal was based on a volumetric rate in the area of 50 cc/min the Government expressed interest in a variety of mass flow rates ranging from 50 cc/min to 2000 cc/min. The physical characteristics such as weight, volume and configuration of a personal sampler are to a large extent - dependent on the operating volumetric rate. It became readily apparent that the optimum size of such an instrument as a function of volumetric rate was not known and that a study of the choice of optima was essential prior to beginning the development, Hence, the Government authorized a two phase approach to this project. Phase I was to include a Technical Evaluation Study of optimum characteristics in the range between 0. 1 to 2. 0 lpm. Based on these findings and in consultation with MESA personnel, the Bureau of Mines was to authorize the second phase that is, the development. Phase II, was to include the drawing of a set of performance specifications stating among others the desired operating volumetric rate. In this report, every effort was made not only to present the actual work done over the course of this development, but to reflect also our engineering "thinking" providing answers as to the "why" we preferred certain solutions over others. We believe that this added dimension is not only useful for the Government official evaluating this report, but also that the Government is entitled to it providing the official with an educational content useful in avoiding future costly repetitions of similar situations.

Jan 1, 1975

By B. W. Gandrud

The upper part of the Alabama deposits of crystalline graphite consists of an oxidized ore derived from the underlying unoxidized ore through prolonged Weathering. The degree of oxidation in different sections and at different depths within the bed is not uniform. The original ore is hard and blue-gray; the weathered product is soft and brown and is the only part that has been mined to any extent. Samples of both oxidized and unoxidized ores were obtained from two of the large graphite deposits of Clay County. Three additional samples of oxidized ore were obtained from different portions of a third property in the same region. In this report, ores 1 to 5 are of oxidized material and ores 6 and 7 of unoxidized.

Jan 1, 1934

By R. L. Soderberg

This paper is one of a series on mining methods and costs being published by the Bureau of Mines. It describes briefly the mining methods employed since the start of operations in 1937, with emphasis on the diamond-drill blast-hole method of ore breaking and slusher-drift method of ore drawing at the Holden mine of the Howe Sound Co., Chelan Division, Holden, Wash. The Holden mine is in the north-central part of the Cascade Range, 11 miles up Railroad Creek from Lake Chelan. The nearest railroad is at Chelan Falls, 40 miles by boat and 4 miles by highway from the mine. All freight comes into the mine and all concentrates are shipped out via Chelan Falls. The altitude of the main haulage level is 3,500 feet. Railroad Creek Valley is covered with a dense growth of fir and spruce, while most of the surrounding mountains are rocky, with sparse timber growth.

Jun 1, 1948

By A. C. Fieldner, SIDNEY GOTTLIEB

This report summarizes the research and technologic work of the Bureau of Mines on coal and coal products from July 1, 1947, to July 1, 1948. It is the thirteenth of a series presenting resumes based largely upon publications issued during the year . In some instances , research and testing results , not otherwise available in published form , are presented . The individual publications given as footnote references herein will provide further detail to the interested reader . The period covered by this report was marked by an ever -mounting concern for the adequacy of the Nation's fuel resources and for fuel shortages arising from an increasing demand for fuels at home and abroad . Several reports appeared which delineated the place of synthetic liquid fuels in the future fuel technology and economy of the Nation , emphasized the fact that eventually the principal raw material for the production of such fuels will bet,5,6 coal, and described the progress made by the Bureau of Mines in developing processes for the production of synthetic liquid fuels . heard testimony along similar lines . Increased awareness of the fuels problems confronting the Nation led to an authorization by the 80th Congress for the erection of an anthracite research laboratory at Schuylkill Haven , Pa . , to house expanded Bureau of Mines research on anthracite . Design of the structure was well under way by the end of the fiscal year . ( See fig . 1. ) Looking forward to expansion of Bureau research on lignite , the 80th Congress heard testimony on the problems and programs of lignite research10, 11 as a prelude to authorizing the construction of a lignite research laboratory in North Dakota .

Aug 1, 1949

By J. D. Brown

The electron optics, vacuum system, and sample stage assembly for the Bureau of Mines? electron probe X-ray spectrograph were purchased. Four scanning curved-crystal spectrometers, two reflection- and two transmission-type, were designed and constructed by the authors. The reflection spectrometers are placed in a vacuum chamber for measurement of long-wave-length X-radiation. Detection, pulse-amplitude discrimination, and recording circuits are provided for the simultaneous measurement of four X-ray spectral lines. Minimum spot size is approximately 2 microns in diameter at 30 kilovolts and a sample-to-ground current of 5 x 10-8 ampere. At this voltage and current the limit of detection with reflection spectrometers is less than 0.05 weight-percent for most elements. The limit of detection for elements determined by transmission-type spectrometers, evaluated at 35 kilovolts and 5 x 10-8 ampere, is approximately 0.1 weight--percent for all elements having excitation voltages below 20 kilovolts. In general, reflection spectrometers exhibited satisfactory but poorer resolution than the transmission type, resolution of the spectrometers being limited primarily by crystal imperfections, with greater mosaic structure being introduced by the grinding process for the reflection crystals. Several applications of the electron probe X-ray spectrograph are described. Analysis of a uranium-steel is discussed in detail to illustrate calculation of composition from measured X-ray intensities.

Jan 1, 1962

By Thomas F. Anderson

(Measurements of stable isotopic variations (sulfur, carbon, and oxygen), supplemented by chemical, mineralogical, and petrographic analyses have been used to investigate the processes responsible for : (1) the incorporation of sulfur in coal, and (2) the (development of permineralized peat zones ("coal balls"). Sulfur isotopic results indicate that there are two principal sources of sulfur in the Pennsylvanian coals from the Illinois Basin: (1) "primary" sulfur assimilated by plants (low-sulfur coals), and (2) "secondary" sulfur produced by reactions involving H2S that was produced by the anaerobic reduction of sulfate in seawater which permeated the peat during post-depositional marine transgressions (the dominant source of sulfur in high-sulfur coals). Sulfur isotopic compositions of low-sulfur coals in Several Tertiary basins of Wyoming are consistent with a plant sulfur source. However, the inverse correlation between content and isotopic composition of sulfur observed in coals from the Powder River Basin suggest some "secondary" additions to these low-sulfur coals. Seveeral Quaternary (freshwater pears which were submerged by sea-Level rises during deglaciation over the past 30 ka have sulfur contents and isotopic compositions similar to high-sulfur coals. Carbon and oxygen isotopic compositions of calcareous coal balls from North America and Europe suggest that (1) the carbonate was derived from variable proportions of oxidized plant matter (typically predominant) and inorganic carbonate, and (2) the carbonate minerals were precipitated from fresh-to-brackish waters. Local geochemical and hydrological conditions were apparently more important than regional depositional environments in controlling the source of carbonate and the development of coal balls.

Jan 1, 1983

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 E. W. Parsons

Permanent support of the back is an important economic factor in maintaining a tunnel or other underground opening in condition to render the service for which it was driven. Timber has been most commonly used for support in tunneling and drifting because of its strength and ease of installation. Even when treated for decay, however, timber is subject to deterioration and, over a long period of time, should not be considered a permanent support. Concrete support or lining is permanent and has been used in tunnels of every size for many years but has been almost exclusively cast in place, a difficult, costly process. This report deals with the design and installation of precast concrete supports to combine the best features of both methods.

Jan 1, 1958

By R. J. Campbell

[The steady increase of aluminum production means a corresponding increase of carbon consumption in the alumina-reduction cells. Improved petroleum techniques constantly reduce the amount of byproduct petroleum-coke production. These, trends threaten the alumina-reduction works with possible shortages of carbon, which must be supplied from some other source. In anticipation of this shortages, an investigation into the possibility of using coal as an alternative source of carbon was begun at the Northwest Experiment Station of the Federal Bureau of Mines. The investigation lit has developed bench-scale methods that produce carbon of higher purity than is required by specifications for anode carbon. Additional work will b required to bring these processes to pilot-plant seals and to prove the suitability of the carbons, produced or aluminum-anode consumption.]

Jan 1, 1956

By Harold M. Smith

This report presents a complete qualitative picture of knowledge of the composition of petroleum as of April 1965. The material is presented in detail on two imaginative maps--one, the Hydrocarbon Hemisphere, depicts the hydrocarbons that have been identified in petroleum; the other, the Heterogeneous Hemisphere, shows the sulfur, nitrogen, and oxygen compounds that have been found. All compounds are placed on the maps according to boiling point. The accompanying text illustrates by structural formulas the several types of hydrocarbon and nonhydrocarbon compounds identified, presents some quantitative data, and points out the possible geochemical significance of a number of the compounds. The possibilities of the Petroleum World of the future are discussed as a function of needed research,

Jan 1, 1966

By Harold M. Smith

This report presents a complete qualitative picture of knowledge of the composition of petroleum as of April 1965. The material is presented in detail on two imaginative maps--one, the Hydrocarbon Hemisphere, depicts the hydrocarbons that have been identified in petroleum; the other, the Heterogeneous Hemisphere, shows the sulfur, nitrogen, and oxygen compounds that have been found. All compounds are placed on the maps according to boiling point. The accompanying text illustrates by structural formulas the several types of hydrocarbon and nonhydrocarbon compounds identified, presents some quantitative data, and points out the possible geochemical significance of a number of the compounds. The possibilities of the Petroleum World of the future are discussed as a function of needed research,

Jan 1, 1966

By B. W. Gandrud

[The Bureau of Mines is conducting an extensive investigation of coal preparation in the Alabama coal fields in cooperation with the University of Alabama coal-mine operators. In this investigation the drainage characteristics of typical coals from the Warrior and Cahaba fields were studied]

Jan 1, 1941

By L. A. Haas

S02 reduction with CO was studied in an integral flow reactor at a nominal flow of 0.5 liter per minute. Reactant gas contained 3 percent SO2, 6 percent CO, and the balance He. SO2 conversion was determined for three different types of catalysts. The first consisted of 16 commercial catalysts used for various chemical syntheses. Only the commercial catalysts which contained transition metals in alumina removed more than 30 percent 80a at temperatures below 510° C. Two other types of catalysts were prepared in the laboratory either by pelletizing equal amounts of powdered alumina and transition metal oxides or by impregnating commercial alumina tablets with transition metal ions. Regardless of preparation techniques, Cr and Fe in alumina were the two best catalysts. The observed results suggest that an intermediate (SCO) is formed by the interaction of surface metal sulfides and carbonyls. Alumina then catalyzes the interaction of SCO with S02 to form the end products (sulfur and carbon dioxide). Over 80 percent S02 was removed at 460° C with 2 grams alumina impregnated with 2.5 percent iron.

Jan 1, 1972

By G. L. Humphrey

Although thermodynamic data for ferrous oxide are among the most important in extractive metallurgy, adequate values have not been available until quite recently. The older data suffered not only from the usual experimental difficulties but especially from lack of the knowledge that ferrous oxide of stoichiometrical composition does not exist as a single, thermodynamically stable crystalline phase under any circumstances. This paper reports new experimental data on the heat of formation of ferrous oxide by two methods (combustion calorimetry and solution calorimetry), employing material of unequivocal composition. The results are compared with values obtained from data for the hydrogen reduction, carbon monoxide reduction, and disproportionation reactions of ferrous oxide, and a best value is selected. A table of heat and free energy of formation values of ferrous oxide to 2,000°K is given. These values are combined with available data for water, carbon monoxide, and carbon dioxide to obtain theoretical heats and free energies of reduction corresponding to the selected heat of formation. Hydrogen and carbon monoxide reduction equilibria are compared, and the differences in trend with temperature and the percentage utilization of the reductants are considered.

Jan 1, 1952

By William Seymour, L. D. Schmidt

"FOREWORDAmong many problems created by World War II, the question of supplies and distribution of raw materials is of outstanding importance. One of the most critical of these raw materials is fuel, and of the fuels coal is of primary importance. The normal consumption of coal has increased greatly owing to the increased tempo of industry in general. It has been necessary to divert much of the fuel oil, gasoline, etc., ordinarily used for industrial and domestic purposes, to supply the enormous demands of mechanized warfare. Coal must be provided to replace this fuel. Furthermore, the enormous increase in the production of steel has increased the demand for coking coals to a critical point.The Solid Fuels Administration for War is encouraging the use of anthracite fines in the production of byproduct coke for blast furnaces for three reasons. First, the production of anthracite for domestic use; is hampered by the inability to find a market for the fines incidental to the production of domestic sizes. Second, the shortage of low-volatile coking coal is acute, and any action that will decrease the quantity of low-volatile coal required will relieve the situation. As will be seen in this report, there is some promise that use of anthracite fines in coke-oven mixes will lower the amounts of low-volatile coal required. Third, utilization of those anthracite fines will tend also to alleviate the general fuel shortage. It has been the privilege of the Bureau of Mines to cooperate with the Solid Fuels Administration in the technical problems involved."

Apr 1, 1945

By A. W. Deurbrouck

This report describes the washability characteristics of 18 coal samples taken from 11 drill hole cores from the San Juan Basin area of New Mexico and Colorado. The ash content of these coals could generally be substantially reduced by removing the heavy impurities. The coals were characteristically low in sulfur content; only one sample contained more than 1 percent sulfur after removing the sink-I.50 specific gravity material. The coals ranged in rank from subbituminous C to high volatile C; 11 of the samples were subbituminous A. Many of these core samples came from areas where very little fieldwork has been done; consequently, an outgrowth of this work has been an increase in known coal reserves of the San Juan Basin area.

Jan 1, 1972