Blogs
Mine Sampling Assays
Table of ContentsStatistical Techniques used for the InvestigationMean-Square-Successive-Difference TestCorrelationSource of Assay Data TestedClimax Molybdenum DepositMean-Square-Successive-Difference TestsCorrelationCebolla Greek Titaniferous Iron DepositMean-Square-Successive-Difference TestsCorrelationSan Manuel Copper DepositMean-Square-Successive-Difference TestsCorrelationDiamond-drill holesChurn-drill holesPiedra Hueca Copper DepositMean-Square-Successive-Difference TestsCorrelationButte Copper DepositMean-Square-Successive-Difference TestsCorrelation A continuing problem in mine evaluation, planning, operations, and production scheduling is the necessity of assigning some value for the grade of mineralization which occurs in
Recover Hydrofluoric Acid from Fluosilicic Acid Waste
Table of ContentsExperimental Procedures and ResultsDirect Hydrolysis of H2SiF6Hydrolysis of Lime-Neutralized H2SiF6 This report describes a preliminary investigation of methods for recovering hydrofluoric acid (HF) from waste byproduct fluosilicic acid (H2SiF6). Fluosilicic acid is generated by plants processing phosphate rock in the manufacture of fertilizer; most phosphate rock contains 3 to 5 percent fluorine in the form of the mineral
Calcium Vanadate Precipitation and Processing
Table of ContentsMaterials, Equipment, and ProcedurePrecipitation of Calcium Vanadate from Synthetic SolutionsPrecipitation With Calcium ChlorideEffect of pH on Precipitate CompositionEffect of pH and the Quantity of Calcium on Precipitate Composition and Vanadium RecoveryEffect of Vanadium Concentration on Completeness of PrecipitationPrecipitation With Milk of LimePrecipitation from Autoclave Leach SolutionProcessing Calcium VanadateDicalcium Vanadate Recovered From Synthetic SolutionLeaching in HCl and H2SO4 SolutionsLeaching
Iridium Electrodeposition
Table of ContentsElectrolysis of Fused Sodium Cyanide ElectrolytesCoatings of Pure IridiumAlloy Coatings of Iridium With Other Platinum-Group MetalsElectrolysis of Aqueous ElectrolytesEvaluation Adherent, coherent electro-deposits of iridium 15 mils thick and alloys of iridium 4 mils thick were formed in argon atmosphere from fused cyanide electrolytes. The use of pure iridium to prevent oxidation appears limited to temperatures under 1,000° C
Magnetic Separation of Pyrite
Table of ContentsPrevious Studies of Magnetic Separation of Pyrite from CoalsPublished WorkUnpublished Studies by the Bureau of MinesPresent Studies of Magnetic Separation of Pyrite from CoalsIntroductionSize Distribution of Pyrite Particles in CoalsMagnetic Susceptibilities of United States CoalsMagnetic Susceptibilities of Some Compounds of IronEnhancement of Magnetism of PyriteEffect of Storage on Sulfur FormsEffect of Pulverization of Coal and PyriteMagnetic Susceptibility and
Smelting low Pyrite Copper Concentrate
Table of ContentsRaw MaterialsEquipment and ProcedureResultsNonpyritic Smelting With Normal SulfurNonpyritic Smelting With Excess SulfurNonpyritic Smelting With Deficient SulfurDiscussion of ResultsGypsum as a Pyrite Substitute A laboratory smelting study was conducted on a copper ore containing chalcocite and native copper to test the technical feasibility of non-pyritic smelting (low pyrite). The results of this investigation led to the following conclusions, based
Columbium Alloys
Table of ContentsMicrostructureX-Ray DiffractionHardnessFabricationRecrystallizationStrengthOxidation ResistanceDiscussion of ResultsSummary As a continuing endeavor, the Bureau of Mines is developing columbium and tantalum alloys for high-temperature applications. This investigation was undertaken to improve the high-temperature properties displayed by the more common columbium alloys that are commercially available. In a previous investigation beneficial improvements were realized by alloying columbium with elements such as hafnium,
Columbium Tantalum Flotation
Table of ContentsContact-Angle StudiesEquipment, Materials, and Test ProcedureContact-Angle ResultsMicroflotationEquipment, Materials, and Test ProcedureMicroflotation ResultsAnionic ReagentsCationic ReagentsBatch Flotation StudiesOka Pyrochlore OreDark Star Ore The purpose of this investigation was to determine the flotation characteristics of important columbium / tantalum ore minerals as a guide for the practical concentration of low-grade columbium ores. Placer deposits amenable to gravity concentration have been the
How to Purify & Concentrate a Manganese Leach Solution
Table of ContentsExperimentPreparation of Leach LiquorTest Equipment and ProcedureResultsKinetic AnalysisKinetic Analysis of Ammonium-Manganese Sulfate Precipitation A temperature of 250° to 260° C was found to be satisfactory for simultaneous removal of iron and manganese from the pregnant leach liquor resulting from leaching of low-grade manganese ore. A holding time of about 15 minutes at this temperature was sufficient for maximum
How to Identify the Surface Texture of Rock
Table of ContentsThe Texture of SurfacesEquipmentProcedure Model studies, using rock, require carefully prepared specimens. Most preparation procedures use some form of grinding or polishing as the last of several steps. During these steps, particularly the final one, the surface formed acquires a configuration defined as texture. Texture is a composite term identifying the physical features called flaws, lay, waviness, and
Electrorefining Yttrium
Tests on electrorefining of yttrium were performed in LiCl-YCl3 electrolytes at 710° C, and the deposits were subjected to vacuum-distillation at 880°C to remove salt from the metal. A comparison of the analyses of the anode feed and the product metal indicates that all metallic impurities were substantially lowered, but oxygen was reduced appreciably only in metal produced from electrolytes
Chlorination Of Ferrochromium
Table of ContentsExperimental ProceduresApparatusPreparation of ChargeChlorination ProcedureLeaching ProcedureExperimental Results Low-temperature chlorination of three types of ferrochromium at 340° to 525° C chlorinated an average of 89 percent of the chromium and 95 percent of the iron contents of the feed materials. From 81.9 to 91.6 percent of the iron was removed by sublimation as FeCl3. The reactor product was a
Zinc Copper Titanium Alloys Cast
Table of ContentsCasting Experimental Ingots With the Semi-continuous Casting MachineIngot MicrostructureChemical AnalysisIngot HardnessSolidification Rate ExperimentsRolling of Slabs from Semicontinuous-Cast Ingots Sound ingots of Zn-Cu-Ti alloys can be semi-continuously cast under appropriate conditions. A modified mold design on a specially constructed, semi-continuous casting stand has permitted casting of ingots having adequate surface quality. With the experimental equipment described, pouring temperatures near
Ammonium Nitrate ANFO Electric Detonation
Table of ContentsDiscussion and Description of the ProblemsFiring of Electric Blasting CapsNature of Charging SourceNature of CapacitorsTime ConstantsSignificant Aspects of the Loader and Its OperatorCharge in the BoreholeExperimental Methods and ResultsRecommended Practices and Procedures for Minimizing Electrostatic Hazard Accidental firings of explosive initiators have occurred occasionally with some uncertain correlation to the pneumatic loading of ammonium nitrate-fuel oil (AN-FO) blasting
Determining Compressive Strength of Rock
Table of ContentsSample Preparation And Testing ProcedureSpecimen VariablesNonparallel EndsRoughened EndsExternal VariablesEnd Platen InfluenceSpherical Head Friction The major conclusion to be drawn from the four series of tests is that reasonable care in preparing specimens and conducting compression tests on a hydraulic machine will provide an acceptable compressive strength value for most applications. For normal uniaxial compression tests, nonparallel ends, end
How to Use Heat to Separate Copper from Steel Scrap
Table of ContentsExperimental Procedures and ResultsStatic Tests Above Melting Point of CopperDynamic Tests Above Melting Point of CopperThermal Treatment Below the Melting Point of CopperMagnetic Separation of Scale FractionsMiscellaneous Embrittlement Tests We initiated a program was concerned with the utilization and disposal of steel scrap, as the pollution and unsightliness caused by the accumulation of steel scrap in junkyards. Maybe
Electrowinning Neodymium
Table of ContentsCell Design and OperationElectrowinning Low-Melting Rare-Earth MetalsPreparation of Alloys by Direct ElectrolysisElectrowinning High-Melting Rare-Earth MetalsContinuous Electrowinning of Cerium and LanthanumProduct Quality Cells were designed and successfully operated on a laboratory scale for electrowinning high-purity neodymium, praseodymium, and didymium, as well as the higher melting-point metals, gadolinium, dysprosium, and yttrium. The elements were prepared from their oxides, dissolved in
Separate Nickel and Cobalt by Electrorefining
Table of ContentsEquipmentElectrolyteOperational ProcedureExperimental ResultsElectrolysis in a Helium Atmosphere CellFactors Involved in the Selective Deposition of NickelCobalt Concentration of the ElectrolyteAnode DissolutionComposition of Anode MaterialEffect of Cathode Current DensityRecovery of Cobalt from the ElectrolyteHigh-Purity Nickel PreparationElectrolysis in Normal Atmosphere CellComparison of Refining in Normal and Helium Atmosphere Cells The electrolytic separation of nickel and cobalt by electrorefining in a molten
Copper Hydrometallurgy
Table of ContentsChemistry of LeachingFactors for Successful LeachingUnderground LeachingConventionalProject SloopEstimated Costs for Nuclear Fracturing and In-Situ LeachingDump LeachingCementation EquipmentConsumption of Iron and Sulfuric AcidAcidSponge IronScrap IronCost Data for Conventional PracticesGeneralPeruvian Mine WatersIn-Situ Leaching in ArizonaCost of Marketable Copper from U.S. Dump LeachingSolvent Extraction of Leach SolutionsIdeologyCarboxylic Acids and Naphthenic AcidLIX-63 ReagentLIX-64 ReagentCost Estimates Using LIX-64 ReagentIon-Exchange Resins for Copper RecoveryMiscellaneous
Recover Copper from Oxides using Iron and Steel Scrap
Table of ContentsPrinciples of Ferrothermic ReductionExperimental ProceduresResults and DiscussionEffect of TemperatureEffect of Reactant ProportionsEffect of Physical Form of the ReductantEffect of Gaseous Environment For the past two decades, about one-third of the copper consumed in the United States has been imported. In order to meet the Nation’s demand, new and improved methods of copper extraction must be found. Ferrothermic extraction
Arsenic Assay Determination by Colorimetric Method
Table of ContentsProceduresISO Recommendation No. 601ReagentsWet Oxidation ProcedureColorimetric DeterminationMgO AshingNitric Acid ExtractionResultsComparison of Three MethodsArsenic in Float- and Sink-FractionsHigh-Temperature Ashing Tests Because of its poisonous qualities, the arsenic which is sometimes present in coal and in the atmospheric dust resulting from coal combustion can present a threat to health. As part of its continuing program to reduce health hazards in
Chrysoberyl Flotation
Table of ContentsMaterials and Test MethodsMaterialsMineralsReagentsTest MethodsResultsContact AngleAnionic SurfactantsSodium OleateSodium Isooctyl PhosphateSodium Heptadecyl SulfateSodium Dodecyl Benzene SulfonateSodium Dioctyl SulfosuccinateFatty Acid AmideCationic SurfactantsPrimary AminesOther Cationic SurfactantsAmphoteric and Nonionic SurfactantsMicroflotationAnionic SurfactantsSodium OleateSodium Isooctyl PhosphateSodium Heptadecyl SulfateSodium Alkyl SulfonateSodium Dioctyl SulfosuccinateCationic SurfactantsPrimary AminesDiamineTertiary Alkyl AmineQuaternary Amine In contact-angle research, 10 of the 17 surfactants evaluated proved to be collectors for Chrysoberyl Flotation. With
Copper Leaching Practices
Table of ContentsMineralogy of Raw MaterialsChemical ReactionsMethods of LeachingDump LeachingEmplacement of DumpsGround PreparationMethod of Dump EmplacementPhysical Nature of DumpsSize of Leach MaterialGeometry and Volume of DumpsSettling of DumpsLeaching OperationLeach SolutionMethods of Solution IntroductionDistribution of Solutions in DumpsTemperature of Leach SolutionsInfluence of BacteriaControl of Iron Salts in SolutionPregnant LiquorOperational Control During LeachingHeap LeachingEmplacement of HeapsGround PreparationMethod of Heap EmplacementPhysical Nature of
Amalgam Electrorefining of Zinc & Tin
Table of ContentsProcedure and EquipmentResults and Discussion The following conclusions are drawn from the results of the laboratory tests of amalgam electrorefining of zinc and tin: Amalgam electrorefining is a method by which these metals may be refined to total metal impurity concentrations of less than 5 ppm in zinc and 9 ppm in tin. The suitability of metal for