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By William Hurst

This is a presentation of the diffusivity theory for the calculation of the water drive on an oil reservoir in which the history of reservoir pressure with time are the essential parameters for the determination of the rate and cumulative water encroachment into a field. The main body of the paper is essentially the application of the principles underlined here to actual field data. It consists of the work plots of the radial-flow case, and includes a discussion of an illustrated problem for which the water-drive calculations are treated in conjunction with the volumetric-balance equation. The appendix is a mathematical treatment of the linear, radial, and spherical cases of water influx into a reservoir. Introduction The evaluation of oil reserves and the prediction of pressure behavior with different rates of production are related to the volumetric balance of the fluids entering and leaving the space occupied by the oil and gas originally present in the formation; that is to say, important information can be gleaned from a volumetric study of the oil, gas, and water produced from a formation as it affects the extent of change in volume of oil zone, the gas cap, and the amount of water influx from the adjoining water sands. It is not the purpose of this paper to enter into a discussion of the equation of volumetric balance, in which such pertinent information as subsurface sampling and the measurement of reservoir pressures play a predominant part, as this has been discussed in detail by others.1,2 However, there is an inherent difficulty that has limited the general application of this equation to a study of oil reservoirs; that is, the insufficient knowledge of the analytics for expressing the water drive on a field as a function of reservoir pressure. This to a large degree has been overcome and it is the purpose of this paper to present this theory in such form as to be applicable for reservoir calculations. Water Drive If the amount of oil originally in place and the gas space are known, it is a relatively simple matter to determine, by the volumetric equation, the cumulative water influx into a reservoir from the adjoining water sands. Often, however, the oil reserve as well as water influx must be 'determined, and in order to be able to make this calculation it is essential to assign a mathematical relationship for the varying water term that is compatible with conditions known to exist in the formation and gives an accuracy acceptable for engineering calculations. Various equations have been employed empirically by different investigators in making reservoir studies of water drive. One form used by Schilthuis2 expresses the rate of water influx into a reservoir at any time as proportional to the pressure

Jan 1, 1943

By R. T. Webber, R. B. Owen

The vapor phase deposition of molybdenum and tungsten from the hexacar-bonyls has been thoroughly investigated by Lander and Germerl, and shown to yield well-bonded coatings on a variety of hot metallic surfaces. They also demonstrated that chromium coatings2'3 could be similarly deposited, but did not investigate this metal extensively. Recently, conditions have been described by which this compound can be prepared in quantities sufficient for laboratory scale plating experiments, and it is the purpose of the present communication to outline the results of preliminary experiments upon the plating of chromium from its carbonyl. Apparatus and Technique The apparatus used in these experiments is shown in Fig I. At one end, connected by a short length of rubber tubing, is a Cenco Hypervac 20 pumping continuously. At the opposite end is a needle valve which allows a small stream of purified hydrogen to flow through the apparatus. Connected in series are a trap T1, maintained at the temperature of dry ice and acetone, the plating chamber, and two traps T² and T3 containing crystals of the carbonyl. T² is kept in a constant temperature bath (not shown), while T³ is at room temperature. Stopcock S6 allows the hydrogen flow to by-pass the carbonyl traps. A McLeod gauge is connected so that it can measure the pressure at the pump through Se, or the pressure at the plating chamber through S9 and S6. The standard (12 liter) volume connected by Sb is used to determine the volume included by S4, S6, SB, Slot the needle valve and the McLeod gauge. Knowledge of this volume allows calibration of the flow of hydrogen. The apparatus* is built entirely of pyrex, except for the needle valve, the rubber connection to the Hypervac, and the cover of the plating chamber. The plating chamber is water-jacketed, with a large brass top allowing insertion of the specimen to be plated. Set into the brass top is a ground glass stopper through which thermocouple leads are sealed. The thermocouple wires (pure Pt, and 87 pct Pt-13 pct Rh) serve the double purpose of measuring the specimen temperature and suspending it in the chamber. Surrounding the chamber is the coil of an induction heater, H. The apparatus is designed to allow variation of the following conditions: (I) the specimen temperature, from room temperature to about 1000°C, (2) the carbonyl vapor pressure, from 40 to 220 microns, and (3) the hydrogen flow. In several runs, 0.8 to 1.8 PCt of hydrogen sulfide was introuced through a needle valve that replaced S4. The vapor pressure of the carbonyl is

Jan 1, 1949

By William Hurst

This is a presentation of the diffusivity theory for the calculation of the water drive on an oil reservoir in which the history of reservoir pressure with time are the essential parameters for the determination of the rate and cumulative water encroachment into a field. The main body of the paper is essentially the application of the principles underlined here to actual field data. It consists of the work plots of the radial-flow case, and includes a discussion of an illustrated problem for which the water-drive calculations are treated in conjunction with the volumetric-balance equation. The appendix is a mathematical treatment of the linear, radial, and spherical cases of water influx into a reservoir. Introduction The evaluation of oil reserves and the prediction of pressure behavior with different rates of production are related to the volumetric balance of the fluids entering and leaving the space occupied by the oil and gas originally present in the formation; that is to say, important information can be gleaned from a volumetric study of the oil, gas, and water produced from a formation as it affects the extent of change in volume of oil zone, the gas cap, and the amount of water influx from the adjoining water sands. It is not the purpose of this paper to enter into a discussion of the equation of volumetric balance, in which such pertinent information as subsurface sampling and the measurement of reservoir pressures play a predominant part, as this has been discussed in detail by others.1,2 However, there is an inherent difficulty that has limited the general application of this equation to a study of oil reservoirs; that is, the insufficient knowledge of the analytics for expressing the water drive on a field as a function of reservoir pressure. This to a large degree has been overcome and it is the purpose of this paper to present this theory in such form as to be applicable for reservoir calculations. Water Drive If the amount of oil originally in place and the gas space are known, it is a relatively simple matter to determine, by the volumetric equation, the cumulative water influx into a reservoir from the adjoining water sands. Often, however, the oil reserve as well as water influx must be 'determined, and in order to be able to make this calculation it is essential to assign a mathematical relationship for the varying water term that is compatible with conditions known to exist in the formation and gives an accuracy acceptable for engineering calculations. Various equations have been employed empirically by different investigators in making reservoir studies of water drive. One form used by Schilthuis2 expresses the rate of water influx into a reservoir at any time as proportional to the pressure

Jan 1, 1943

DEVELOPMENT of a chemical process for the extraction of pure metals from mill concentrates or metal scrap has progressed beyond the pilot plant stage and may prove an important adjunct to present smelting and refining methods if initial commercial operations prove economically successful. Developed by the Chemical Construction Corp., the new process involves the treatment of oxide and sulphide ore concentrates by chemical methods, instead of the usual smelting and refining techniques. Several of the many applications are now scheduled for commercial use. Refiners using the new process will prepare ore concentrates by standard flotation methods, introduce the concentrate as a slurry into an autoclave along with water and an acid or ammonia. From the resulting leach solution, recovery of individual metals is made by use of suitable reducing agents. By varying conditions during treatment, different metals in the ore are produced separately as pure powders, which may be pressed into forms ready to market, or in the case of copper, extruded as rods or pipe. The reagents are generally recovered. By manipulating the variables during reduction, selective separation of nickel, and/or cobalt, and/or copper can be made simultaneously. The separation is a continuous operation. Low metal prices are not immediately in view because of the tremendous demand at this time. However, reduced metallurgical treatment costs will allow economical mining of orebodies with lower metal content, permitting increased production to meet demand. Although the practical horizon for use of the new process appears to be limitless, one factor may enter into its employment. Just how low grade a concentrate can be economically used is unknown. In addition, for present practical considerations, only metal below zinc in the electromotive series may be processed. Each commercial application requires specific technique adaptation and pilot-plant data for engineering design. A nickel-cobalt-copper process has been researched and piloted in collaboration with Sherritt Gordon Mines, Ltd., for the firm's Lynn Lake properties. In addition, processes were tailored for cobalt concentrates of Howe Sound Mining Co., and National Lead Co., in view of the urgent need for this specific metal. Major General William N. Porter, president of Chemical Construction, says of the new process, "piloting experience has shown that production cost, from ore concentrates to pure metals should be considerably below current costs." Other savings may be realized by cutting transportation and personnel costs, and by reducing the time lag between mining and pure metal from months to a matter of hours. First commercial use of the process will start sometime this summer. Chemico is slated to finish building a $2.5 million cobalt refinery for Howe Sound Mining near Salt Lake City. The plant is expected to raise world cobalt production by 40 pct. The plant will process 35 tons of 20 pct cobalt concentrates from Howe Sound's Blackbird mine near Cobalt, Idaho, daily. Yearly production is expected to reach 2000 tons of pure metal, about one half of U. S. consumption in 1950. Steps in the Howe Sound application of the process are: 1. Acid oxidation leach. 2. Filtration (residues thrown away are insoluble compounds-gangue, iron, arsenic). 3. Cementation (for Cu removal because Cu content is too low for recovery). 4. Reduction from ammoniacal solution. 5. Separation of Co and Ni as mixed metals (95 pct Co and 5 pct Ni). 6. Recovery of ammonium sulphate. Under construction at the Fredericktown, Mo., mine of National Lead is a $5 million refinery sched- [ ]

Jan 1, 1952

By K. L. Komarek, P. F. J. Landler

Synthetic polycrystals of wustite were reduced ilz H2-H2O mixtures over limited roncentration ranges wiltun the wustite. field and the weight changes were continuously followed with a McBain quartz spiral balance. The reduction was. found to be controlled by a combined surface plus solid-state diffusion reaction. The solid-state diffusion had an activation energy of 38 kcal. Self--diflusioities of iron decreased with itzcreasing vacancy concentration. The activation energy of. the surface reaction runs different tor- different samples. The surface reaction-rate constan increased with increasirzg vacancy concentration. THE reduction of the oxides of iron has been studied for many years. Edstroem' has summarized the early work and has provided much information on the reduction of magnetite and hematite by hydrogen and carbon monoxide. More recent summaries are those by smeltzer2 and Themelis and Gauvin.3 Most investigators have reported that the iron metal which forms the outer layer during gaseous reduction is rather porous. According to Kohl and Engel14 the formation of such a porous iron layer depends on the properties of the underlying wiistite layer, on the reaction of the gas with the wustite surface, and on the transport of matter through the wustite layer. McKewan, Quets, Wadsworth, and Lewis, and Knacke 10 have found that, if a porous iron layer is formed, a surface reaction between gas and wustite at the bottom of the pores controls the rate of reaction. Seth and ROSS 11 and Warner 12 have pointed out that the influence of the gaseous pore diffusion through the porous iron layer cannot be neglected. It has further been shown that the wiistite layer formed during reduction is dense and that transport of matter across the layer occurs only by solid-state diffusion of iron ions.13,14 The solid-state diffusion rates observed by Edstroem and Bitsianis 14 and the surface reaction rates observed by Quets eta1.' show that an interaction of the two steps in controlling the reaction rate has to be considered. In this investigation the reduction of wustite was studied with respect to the interaction of the two steps, isolated from any other effects, by reducing wustite within the wustite field from higher to lower oxygen concentrations with H2-H2O gas mixtures. A similar study with CO-CO2 mixtures has been performed by Levin and wagner.15 Fused synthetic wustite polycrystals were reduced in steps of 0.4 wt pct from 24.4 to 23.2 wt pct 0 and over a temperature range from 700" to 1050°C. A few tests were also conducted with reduction steps from 24.4 to 23.6 wt pct 0 and 24.5 to 23.2 wtpct0. The Fe-O phase diagram is shown in Fig. 1 where the composition of the gas phase in equilibrium with the condensed phases is plotted as pct H2 vs the temperature. A careful study of the literature led to the conclusion that the fully drawn equicomposition curves (in wt pct O) in the wustite field used by Edstroem 1,16 and other authors needed some correction. Based on results by Darken and Gurry17 (shown as open circles) and on some of our own data, four corrected curves for 23.2, 23.6, 24.0, and 24.4 wt pct O were calculated (drawn as dashed lines in Fig. 1) which should replace the fully drawn equicomposition curves. MATERIALS AND APPARATUS Materials and Specimen Preparation. Wustite was prepared from iron sulfate (Fisher Scientific Co., New York) which had a purity of over 99.92 pct, with small amounts of manganese, copper, and zinc adding up to 0.03 pct. From the aqueous solution iron oxalate was precipitated and decomposed to magnetite according to Economos. 18 The magnetite powder was pressed into cylinders and sintered in vacuum at 900°C for several hours. The sintered compacts were placed in a platinum crucible of 2.5 cm diam which was fitted into a high-purity alumina crucible and then inserted into the center of the graphite heating element of an electric resistance furnace.lg The furnace was evacuated to below 1 p Hg and the magnetite sample was slowly heated. The evolution of gases during heating deter-

Jan 1, 1967

By E. T. Knight, John D. Gill

Much has been written and said concerning the alleged wasteful and uneconomic use of natural gas and petroleum. Espccially condemned has been the use of natural gas for the production of carbon black and the use of heavy fuel oil under steam boilers.' The critics of these usages of gas and oil have sought to make effective their verbal attacks on the industry by the repetitive expression of the words "inferior" and "superior" uses2 of petroleum. Thus, to employ natural gas for residential heating was to use it in a superior way; to use it for the production of carbon black was to use it in a wasteful and uneconomic way. To use petroleum for the production of automotive fuel was to use it in a superior way; to employ it as a residential fuel and as the prime source of power in an industrial plant was to use it in an inferior and uneconomic way. No doubt the objections to such employment of gaseous and liquid natural hydrocarbons originated in the belief that natural gas and petroleum are limited, nonregenerative mineral resources, and that the functions they perform can be just as well performed by other natural resources like coal13 of which practically unlimited reserves are known. The generations that have dominated each of the last four decades have counted reserves4 of petroleum in terms of a few years supply. Meanwhile, domestic demand for motor fuel rose spectacularly from a few million barrels in 1900 to more than 500,000,000 bbl. last year.5 The more imaginative and vocal critics drew startling word pictures of the catastrophe of 25,000,000 motor vehicles made useless and of the great automotive manufacturing and allied industries brought to an untimely end, and millions of workers left hopelessly unemployed by what they called the deplorably rapid depletion of the petroleum reserve. Many of the critics have been sincere advocates of the conservation of natural resources; many others, and in recent years probably the majority, have espoused the doctrine of conservation to promote their own self-interest rather than that of the public. The latest advocate of severe restriction in the use of petroleum for the alleged purpose of conserving the petroleum resource proposes to achieve that end by a bill,6 now before

Jan 1, 1938

Improved safety, economy, and flexibility-which translate into increased productivity-promote the case for greater utilization of diesel-powered equipment in underground coal mines. On the other hand, opponents of diesel use say that the alleged health hazards are not worth it. Who's right? The continuing debate was the focus of a special "Diesels in Underground Coal Mining" session held during the SME-AIME Fall Meeting in Lake Buena Vista, Fla., last September. Looking at the record to date, there are more than 20,000 diesel-powered units operating in underground mines throughout the world; more than 1000 are in Western European coal mines and 10,000 such units are in North American mines. Surprisingly, of the 10,000 North American units, only 200 are utilized in US underground coal mines.

Jan 4, 1979

Jan 1, 1888

By Henry S. Rawdon

The relation between the course, or path, of the fracture of metals and alloys, produced in service or as a result of certain laboratory tests, and the crystalline units of which such materials are composed is of utmost importance. The fracture of normal material is, in general, intracrystalline, i.e., it consists of a break across the grains rather than of a separation between them. An interorystalline fracture indicates either that the metal is of very inferior quality or that the break occurred under very unusual conditions, e.g., at a very high temperature. The usual mechanical tests, when applied to metals of the type that breaks with an intercrystalline fracture, merely measure the coherence of adjacent grains for one another and reveal little as to the real properties of the metal itself. Even such a soft plastic substance as lead, under suitable conditions, may be rendered so weak and brittle that the metal can be easily crumbled into powder by the fingers although the constituent grains have lost none of the intrinsic properties of lead. Various erroneous explanations of this behavior of lead have appeared in the scientific literature, the change being described usually as an allotropic one. The importance, in an industrial sense, of a proper explanation of this type of the corrosion of lead justifies the description of the type of metal deterioration that follows. Corroded Lead Sheathing In Figs. 1 and 2 are shown two typical specimens of corroded lead sheathing selected from materials submitted to the Bureau of Standards for examination. Fig; 1 shows a section of the sheathing of an aerial cable; Fig. 2, that of the lead covering of a subterranean feeder-line of an electric light system. In this case the deterioration had proceeded to a much great'er extent than in the case shown in Fig. 1 so that certain portions of the metal could easily be crumbled into a coarse gray powder by the fingers. This was particularly true of those portions of the sheathing

Jan 1, 1921

By J. W. Hickman, E. A Gulbransen

The physical and chemical structure of the oxide films formed on metals and alloys is of interest in our understanding of their protective properties. According to Pilling and Bedworth,¹ if the specific volume of the oxide is equal to or greater than that of the metal, a compact or continuous structure results; if the volume of the oxide is less, a cellular or porous structure forms. With the cellular type of coating the surface layer of oxide offers no impedance to oxidation; at a given temperature the rate of oxidation is quite constant. On the other hand, the compact type of coating acts as an effective barrier to oxygen and the rate of oxidation will follow a parabolic law. The recent work of Gulbransen2 and of Leontis and Rhines3 on the oxidation of magnesium indicates that it is not necessary for the volume of the oxide to be greater than that of the metal in order that the oxidation may follow a parabolic rate law. One exception to the rule of Pilling and Bedworth¹ is noted by Scheil;4 namely, tungsten. At 500° and 700°C long-time oxidations indicate a linear rate law with time. However, Dunn's6 0xidation measurements from 700°to 1000°C indicate that a parabolic rate law is followed. The oxide is mainly yellow WO a with a thin layer of the blue oxide. Preliminary results on the oxidation of tungsten6 in the temperature range 400° to 500°C indicate that the oxidation does proceed according to a parabolic rate law. Irrespective of the actual rate law that tungsten may obey, it is of interest to compare the results obtained on the oxidation of tungsten in the thin film region with those found when the metal is scaling. A time-temperature study of the oxides formed on both molybdenum and tungsten may indicate whether there exist any peculiarities in the oxide structures of the thin film region compared with those of the scaling region of oxidation. In a recent paper the authors7 presented an investigation of the structures of the oxide films formed on the metals iron, cobalt, nickel, chromium and copper. The results of these studies are presented in graphical form as existence diagrams of the oxides on a time-temperature scale. The existence diagrams of the oxides occurring on some of the metals are simple and show few chemical transitions, but there are many cases in which the physical state of the oxide surface changes as a function of time and temperature, as evidenced by the appearance or disappearance of orientation effects and sharpness of patterns. In general an increase in temperature results in an increase in

Jan 1, 1947

By E. A. Gulbransen, J. W. Hickman

The physical and chemical structure of the oxide films formed on metals and alloys is of interest in our understanding of their protective properties. According to Pilling and Bedworth,¹ if the specific volume of the oxide is equal to or greater than that of the metal, a compact or continuous structure results; if the volume of the oxide is less, a cellular or porous structure forms. With the cellular type of coating the surface layer of oxide offers no impedance to oxidation; at a given temperature the rate of oxidation is quite constant. On the other hand, the compact type of coating acts as an effective barrier to oxygen and the rate of oxidation will follow a parabolic law. The recent work of Gulbransen2 and of Leontis and Rhines3 on the oxidation of magnesium indicates that it is not necessary for the volume of the oxide to be greater than that of the metal in order that the oxidation may follow a parabolic rate law. One exception to the rule of Pilling and Bedworth¹ is noted by Scheil;4 namely, tungsten. At 500° and 700°C long-time oxidations indicate a linear rate law with time. However, Dunn's6 0xidation measurements from 700°to 1000°C indicate that a parabolic rate law is followed. The oxide is mainly yellow WO a with a thin layer of the blue oxide. Preliminary results on the oxidation of tungsten6 in the temperature range 400° to 500°C indicate that the oxidation does proceed according to a parabolic rate law. Irrespective of the actual rate law that tungsten may obey, it is of interest to compare the results obtained on the oxidation of tungsten in the thin film region with those found when the metal is scaling. A time-temperature study of the oxides formed on both molybdenum and tungsten may indicate whether there exist any peculiarities in the oxide structures of the thin film region compared with those of the scaling region of oxidation. In a recent paper the authors7 presented an investigation of the structures of the oxide films formed on the metals iron, cobalt, nickel, chromium and copper. The results of these studies are presented in graphical form as existence diagrams of the oxides on a time-temperature scale. The existence diagrams of the oxides occurring on some of the metals are simple and show few chemical transitions, but there are many cases in which the physical state of the oxide surface changes as a function of time and temperature, as evidenced by the appearance or disappearance of orientation effects and sharpness of patterns. In general an increase in temperature results in an increase in

Jan 1, 1947

By C. A. Queener, W. L. Mitchell

In recent years bismuth telluride has received considerable attention, primarily due to its value as a thermoelectric material. Since there seems to be little dependence of thermoelectric effect upon crystal orientation1 many of those who have previously worked with this material have been unconcerned with knowing its crystallographic angles to any degree of accuracy. However, when one studies deformation modes, lattice stresses, or the aniso-tropy of mechanical properties of a material, knowledge of the interplanar angles and their relationships as depicted in a stereographic projection becomes essential. Lange2 originally published crystallographic data which described the structure of bismuth telluride as rhombohedral with the space group A more recent work by Francombe3 presented data which corroborated and refined the original findings of Lange. In addition, Francombe established that there is no coexistence of rhombohedral and hexagonal lattices in bismuth telluride as was suggested by Vasenin and Konovalov,4 and that the structure can be treated as a pseu do hexagonal structure with an axial ratio, c/a, of 6.95 for convenience of presentation and study. The interplanar angles and standard projections for several unalloyed hexagonal metals have been previously published,5-9 but the present work appears to be unique in that it presents data for a rhombohedral compound in pseudohexagonal form. As a pseudohexagonal structure, this material has an extremely large axial ratio as compared to the usual range of approximately 1.5 to 1.9 for the hexagonal metals. Since the interplanar angles are a function only of c/a, the angular relations between various planes for Bi,Te3 will be grossly different

Jan 1, 1965

By D. S. Flett, A. W. Fletcher

Equilibrium studies on the extraction of nickel and cobalt with kerosine solutions of naphthenic acid have shown that an exchange extraction reaction occurs at pH 5.5. The nickel/cobalt separation factor is constant at 1.8 for constant total metal molarity and varying nickel/cobalt ratios. The separation factor decreases with increasing total metal molarity in the organic phase beyond 0.2 M and also decreases with increasing temperature. From the equilibrium data, it has been possible to derive a mathematical model for the separation of nickel from cobalt by exchange extraction in multistage systems. Experimental data from a continuously operated multistage mixer/settler apparatus has shown a reasonable correspondence with computer-calculated data. The effective separation of nickel and cobalt in sulfate solution remains a problem in hydrometallurgy and the hope that this would be solved by solvent extraction has not yet been fulfilled. With chloride solutions, advantage may be taken of the ability of cobalt to form anionic complexes with the chloride ion. It can then be readily separated from nickel, which does not form stable chloro complexes, by extraction with a suitable long chain amine. However, in hydro metallurgical operations, sulfate solutions are generally obtained in which no extractable anionic species are present. Thus, the possibility of using cationic extractants must be considered, and in this paper attention is directed to the use of carboxylic acids. The method of separation studied has been termed exchange extraction, which involves replacement of a metal in the organic phase with a more acidic metal in the aqueous phase. Thus, (BR2).+ (Az+)aqt=(AR,).+ (B2+)aq (I) where metal A is more acidic than metal B, R represents the acidic radical derived from the acid RH, and the subscripts e and aq refer to the organic and aqueous phases, respectively. Ashbrook and Ritcey' have used this method for the separation of cobalt from nickel using the sodium salt of di-2 ethyl hexyl phosphoric acid, which preferentially extracts cobalt. Some nickel is coextracted, and this is removed by exchange with cobalt ions in the feed solution by suitable countercurrent operation in a pulsed column. Much work has been carried out by a number of workers in Russia on the general use of exchange extraction for the separation of metal ions using car-boxylic acids. Gindin et aL a have demonstrated that this technique could be applied to the separation of nickel from cobalt using a C--C. carboxylic acid and have applied the technique to the production of high purity cobalt solutions for electrolysis. Further worka was concerned with the development of a process for the separation of nickel from cobalt in a pulsed column. This system permitted the separation of iron and copper from nickel and cobalt in one system. The procedure involved center feeding with acid backwashing at the top and alkali addition lower down the column. Thus the system operated under a pH gradient and the metals were distributed in the column in the order of their basicities. A similar application was studied by Gel'perin et al,4,5 for the removal of copper and iron impurities from a nickel anolyte by means of a C10-C,12 fatty acid fraction. Ginden et al,' and Fletcher and Wilson' have studied the effect of pH on the extraction of a number of metals with carboxylic acids. These studies showed that metals such as iron, copper, lead, zinc, nickel cobalt, and manganese are extracted at pH values close to the pH of hydroxide precipitation. Nickel is extracted at a slightly lower pH than cobalt and thus the nickel/cobalt separation factor has a value not much greater than 1. More basic work on complex identification has been reported by Fletcher and Flett: by Tanaka; and Jay-cock and Jones." These studies have suggested that at low loadings in the organic phase, the nickel and cobalt carboxylates appear to be dimeric and solvated by free carboxylic acid molecules. As the concentration of metal in the organic phase increases, the complex changes and larger polymeric species are formed. In order to permit assessment of the potential of carboxylic acids as extraction reagents for separation of

Jan 1, 1971

By R. P. Carreker

ONE of a series, this report is concerned with the experimental documentation of the deformation behavior of pure metals over a wide range of temperature. Previous reports in the series describe the creep behavior of platinum1 and aluminum2 and the tensile behavior of copper,&apos; silver,& and molybdenum.5 Subsequent reports will describe the creep behavior of copper and silver and the tensile behavior of platinum, thus providing extensive creep and tensile data on four face-centered-cubic metals tested under comparable conditions. Material Two lots of high-purity aluminum were used in this investigation. One lot, designated AC, was obtained direct from the Aluminum Co. of America as high-purity aluminum in notch-bar form. A typical analysis of this type of aluminum is 0.006 pct Si, 0.015 pct Cu, 0.006 pct Fe, and 99.975 pct Al. Lot BS was obtained from J. I. Hoffman of the Bureau of Standards as a portion of the Aluminum A described in his report of the redetermination of the atomic weight of aluminum.6 Lot BS originated with the Aluminum Co. of America also, and was received in the standard notch-bar form. A detailed chemical and spectroscopic analysis of lot BS has been published.6 Principa1 impurities were 0.006 pct Si, 0.003 pct Fe, 0.002 pct Cu, and >99.987 pct Al. Samples were processed identically by room-temperature swaging and drawing to 0.030 in. diam wires from approximately ½ in. diam rods that were machined from the notch-bar pigs. Samples were cut from the cold-drawn wire, placed in a grooved graphite block in groups of thirteen, and annealed in air for 1 hr at each of several temperatures, with the results shown in Table I. The two lots of aluminum responded quite differently to annealing, the behavior of aluminum AC suggesting that its grain growth was controlled by impurities. The recrystallization texture of aluminum of similar purity comparably treated has been reported as predominantly <111> fiber with some <100> fiber present.7 Testing Procedure The testing procedure and method of analyzing the data have been described previously.2,3 Annealed specimens of 5 in. gage length were tested in an Instron tensile testing machine at a constant head motion corresponding to a strain rate of 0.04 min-&apos; at a number of temperatures. Instantaneous tenfold rate changes were employed in some tests to deter-

Jan 1, 1958

By E. A. Gulbransen, W. S. Wysong

The behavior of tungsten and its surface oxides in oxidizing and reducing atmospheres and in high vacua at elevated temperatures is a question of considerable technical importance. The use of tungsten as a a Or as an important component in alloys in high temperature Oxidizing atmospheres has been limited because of the unprotective nature of its oxide film and the volatility of its oxide. This paper will present results of a micro-balance study of the following problems: (1) the oxidation behavior in the ternperature range of 25 to 550°C (&apos;) the reduction with pure hydrogen Of thin Oxide films formed On tungsten, and (3) the volatility Of thin Oxide films On tungsten. Tungsten is an interesting metal to study for the following reasons: (1) although the Oxide to to ratio is greater than one, the oxide is not considered protective, (&apos;1 the meta1 readily Oxidizes at temperatures from 30" to 55o°C (3) the oxides WO² and WO³ are reduced at temperatures as low as 500°C. by hydrogen, and (4) the Oxide WO3 is volatile at temperatures from 800 to 1100°C. Literature The oxidation of tungsten in its thin film range has not been studied critically. In the thick film range Dunn3 has made the only systematic study. He found the oxidation rate to obey the parabolic rate law in the temperature range of 700 to 900°c. The temperature variation of the oxidation rate constant was found to follow an exponential law of the Arrhenius type. An inflection was noticed in the temperature plot of the rate law constant at 850 to 900°C. This was attributed to a phase change in the oxides, Schei14 has studied the oxidation rate at 500 and 700°C over long periods of time and found a linear rate law. This result was interpreted as evidence for the presence of a nonprotective film. Pilling and Bed-worth&apos;s5 analyses of the oxide volume to metal volume ratio would indicate that a compact protective film should form. McAdam and Geil6 have studied the oxidation of tungsten in the thin film range using the interference color method. A parabolic rate law was found. Their curves showed that tungsten oxidizes faster than nickel but more slowly than iron. The lattice structures found in the oxidation of tungsten surfaces have been studied by Hickman and Gulbransen.? They have reported that WO3 is the stable oxide in contact with the metallic substrate up to approximately 600°C while wo³ forms first at 7oo°c. Hagg and Magneli8 have recently reported a study of the lattice structures . observed in the tungsten oxidcs using the X-ray diffraction method. In addition to an a-phase WO3 and a &apos;-phase WO2, they reported the existence of two new phases. A 8&apos; phase, homogeneous between

Jan 1, 1949

By C. L. Meyers, J. L. Lytton, T. E. Tietz

The recovery of tensile flow stress of 99.995-pct Al and Al-1 pct Mg alloy was investigated using a fractional recovery parameter. Tensile strainirg was conducted at room temperature, and recovery treatments were made in the range from 80° to 200°C. Equal values of fractional flow stress recovery were found to result in equivalent structural states. Identical recovery treatments were found to produce constant values of fractional flow stress re covery, independent of prestrain. The activation energy for recovery of the 99.995-pct A1 between 80" and 200°C was found to be 23,000 +2000 cal per mole, and the activation energy for the Al-1 pct Mg alloy was 27,500 cal per mole. 1 HE degree of recovery of a cold-worked metal may be studied by measuring the changes which take place in any of a number of properties. Some of the properties which have been used by past investigators include X-ray diffraction phenomena, electrical resistivity, hardness, creep strength, elastic limit, and flow stress. Despite the apparent preponderance of such studies, little is known concerning the effect of recovery on the strength of metals except as deduced from changes in various types of hardness measurements. Furthermore, little information is avail- able concerning the effects which specific solute atoms have on the recovery process. Limited studies have indicated that in some cases solid-solution additions greatly decrease the rate of recovery,&apos; whereas in at least the case of magnesium additions to alluminum an increase in the rate has been reported.2 The purpose of this investigation was to determine the effect of a 1 pct Mg addition on the recovery of high-purity aluminum. Because of the particular interest in the effect of solute additions on the recovery behavior as related to mechanical properties, the degree of recovery was evaluated in terms of tensile flow stress. For the purposes of this study, a recovery process shall be defined as any process, short of recrystallization, whereby the properties, of work-hardened metals tend toward their values ill the unstrained state. EXPERIMENTAL PROCEDURE Test Materials. The materials used in this study were a 99.995-3 A1 and an Al-1 pct Mg alloy made from high-purity base metal. The high-purity aluminum contained the following wt pct impurities: 0.001 pct Cu, 0.002 pct Fe, 0.001 pct Si, and 0.0004 pct Mg. The Pil-1 pct Mg alloy contained 0.001 pct Cu, 0.002 pct Fe, 0.003 pct Si, and 0.99 pct Mg. Both materials were obtained in the form of as-rolled 0.125-in.-thick sheets, from the Alcoa Research Laboratories, New Kensington, Penn. Tensile specimens were cut from these sheets with the longitudinal axis in the rolling direction. Both materials were recrystallized in a molten salt bath; the high-purity aluminum at 450° C for 20 min and

Jan 1, 1962

By William C. Waldbieser

Webster&apos;s Third New International Dictionary defines new in part as "having been seen or known but for a short time although perhaps existing before." It has recently become fashionable to talk about the new life for old "King Coal," and how we will have to double or even triple our coal production by 1985, or how the US will become energy-independent by 1980. Since coal represents over 80% of our proven energy reserve, the nation will turn to coal as a savior in our time of energy crisis, so goes the argument.

Jan 10, 1974

By P. D. Bush, E. H. Gates, M. D. Vijayaraghavan, L. F. Engle

The process developed over the last few years by Republic Steel Corporation in conjunction with Colorado School of Mines Research Institute has been used as a basis for the conceptual engineering of full size plants. The paper will cover the equipment design criteria, equipment design itself, and the integration of the complex unit operations. There are unique features of agitation and use of gas media through- out. The paper will provide an illustrative example of the process requirements for a variety of raw material feeds. It will discuss the materials of construction approach required.

Jan 1, 1973

By J. M. Hassler

Nowhere can there be found a more misleading statement than the old one that "Iron can be manufactured cheaper in the South." During the past decade ironmakers and users of iron have heard varied and sundry stories of the wonderful resources of the Birmingham district, including abundant ore and coal fields, cheap labor, a wonderful climate and similar industrial Utopian statements. Birmingham represents the major portion of the iron business in the South, and as Birmingham fares so goes the iron business of the South. The intent of this paper is to shed some light on the actual conditions surrounding ironmaking in the South, especially in the Birmingham, or North Alabama, district. By a presentation of facts it is desired to point out that the "cheap iron" of the industrial South is a thing of the past, primarily because of increased labor cost and because labor is radically different in performance to what it was years ago. Also, because most of the raw materials needed in ironmaking that would be classed better than inferior are gone. Important Factors The several important factors that have been responsible for this change are : 1. Shrinkage of the iron business in the South. 2. Increased labor cost. 3. The development of the South, with an industrial trend, without a substantial increase of its own iron-consuming market. 4. Increased freight rates, which has narrowed the market that might be reached from this district. 5. Depletion of the better grades of raw materials, both ore and coal. Shrinkage of Iron Business in South.—Table 1 was prepared in early 1936 and revised in 1937, of blast-furnace units in the North Alabama district, considering the year 1936 compared with a maximum number of furnace units of previous years, the peak point being very near the year

Jan 1, 1937

By J. B. Shannon, J. D. Grenia

The Buick Mine is a joint venture of American Metals Climax, Inc. and Homestake Mining Company located 120 miles by road southwest of St. Louis, near the village of Boss, in the `New Missouri Lead Belt&apos;. Since start-up in 1969, over four million tons of lead-zinc ore have been mined and milled at Buick. Situated 1100 ft below the surface at an elevation 270 ft above sea level, the flat lying sinuous orebodies are up to 250 ft wide, 85 ft high and several thousand feet long. Mineralization is galena, sphalerite and chalcopyrite in dolomite.

Jan 7, 1973