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CreatorTitleDescriptionSubjectDate
126 Miller, Jan D.Selectivity considerations in the amine extraction of gold from alkaline cyanide solutionsIt has been discovered that gold can be extracted from alkaline cyanide solution with primary, secondary, and tertiary amines by adding certain Lewis base modifiers, such as organic phosphorus oxides. Under these circumstances, gold can be extracted at about pH 10, commensurate with the pH of cyani...Gold; Amines; Alkaline cyanide; Extraction1984
127 Miller, Jan D.Separation of bitumen from Utah tar sands by a hot water digestion-flotation techniqueTar sand deposits in the state of Utah contain more than 25 billion bbl of in-place bitumen. Although 30 times smaller than the well-known Athabasca tar sands, Utah tar sands do represent a significant domestic energy resource comparable to the national crude oil reserves (31.3 billion bbl). Based ...Tar sand; Utah; Bitumen; Hot water separation; Froth flotation1978
128 Miller, Jan D.; Wan, Rong YuSignificance of carbon properties in the enhanced ferric sulfate leaching of CuFeS2/C aggregatesAcid ferric sulfate solution has been used for heap and dump leaching of low-grade chalcopyrite ores and is being considered as a possible lixiviant for the hydrometallurgical processing of copper sulfide concentrates. For many years, researchers have attempted to explain the leaching behavior of ch...Ferric sulfate; CuFeS2; Particulate carbon1984
129 Miller, Jan D.Significance of electrokinetic characterization for interpreting interfacial phenomena at planar, macroscopic interfacesStreaming potential measurements provide valuable information for the validation and interpretation of interfacial phenomena that occur at flat macroscopic surfaces. Planar substrates have been extensively used for the interpretation of events, which occur at particulate surfaces; however, these fla...Interfacial phenomena; Surface charge2005
130 Miller, Jan D.Significance of graphitic structural features in gold adsorption by carbonThe nature of surface sites for the adsorption of gold from alkaline cyanide solutions has been investigated using samples of synthetic, highly-oriented pyrolytic graphite (HOPG). This HOPG material offers an idealized graphite structure enabling the independent study of the graphitic basal-plane ...Graphite carbons; Gold; Adsorption1992
131 Miller, Jan D.Solvent extraction reagents for gold recovery from alkaline cyanide solutionsThree different solvent extraction systems for the recovery of gold from alkaline cyanide solutions are reviewed. These include the modified amine extractants in which the basicity of simple alkyl amines, with respect to the aurocyanide anion, is controlled by the addition of alkyl phosphorous ester...Solvents; Extraction; Gold; Alkaline cyanide; Amine extractants; Solvating extractants; Substituted guanidines1993
132 Miller, Jan D.;Yu, QiangSolvent refining of coal resin concentratesCertain bituminous coals of the western United States are known to contain appreciable quantities of macroscopic resinite (fossil resin). Such resinous coals are found in the states of Arizona, Colorado, New Mexico, Utah, Washington, Wyoming, etc. Among these, the Wasatch Plateau coal field in ce...1994
133 Miller, Jan D.Spectroscopic analysis of passivation reactions for carbonaceous matter from carlin trend oresAbstract. Three different refractory carbonaceous gold ores from the Carlin operation in northeastern Nevada were investigated to characterize the effect of passivation treatments on the nature of the carbonaceous material. The carbonaceous material was chemically isolated from the ores and pass...Gold; Chlorine; Cyanidation1990
134 Miller, Jan D.Structure and composition of commercial copper chelate extractantsThe structure, properties, and composition of commercial chelating-type copper extractants are examined. Characterization of these extractants was accomplished using organic separation techniques and analytical tools such as NMR and infrared spectroscopy. Results indicate that only the trans isomer ...LIX® reagents; stoichiometry; reaction mechanism1973
135 Miller, Jan D.Study of particle-bubble interaction using atomic force microscopy: current possibilities and challengesStudy of interaction forces between mineral particles and air bubbles is a key to understanding flotation processes. Measurement of such interaction forces has only recently been made possible with the introduction of the atomic force microscope (AFM) and the colloidal probe technique. Using AFM, in...Particle-bubble interaction; Atomic Force Microscopy (AFM); Hydrophobic force; Contact angle; Hydrodynamic force2002
136 Miller, Jan D.Surface characterization and new tools for researchIn the selective separation of mineral phases by flotation, surface chemistry is the principal determinant of the average contact angle for a specific mineral phase in flotation pulp. The average contact angle is, in turn, the principal determinant of the bubble-particle attachment efficiency in th...Flotation; Minerals; Surface chemistry; Contact angle2007
137 Miller, Jan D.Surface chemistry of pulping and flotation for mixed office wastepaperThe effect of pulping reagents on the de-inking flotation of laser printed wastepaper was investigated with regard to the removal efficiency of toner and mineral filler particles at different pH values. These results show that caustic pulping causes the toner to be released from the fibers as larg...Pulping reagents; Deinking; Toner; Mineral fillers1997
138 Miller, Jan D.Surface phase transitions of adsorbed collector molecules as revealed by in-situ FT-IR/IRS spectroscopyIt has been shown by inspection of FT-IR/IRS spectra that the alkyl conformation of adsorbed collectors can be determined. The conformations of adsorbed collectors were interpreted in terms of bulk solution phases of the collectors. Such analysis was performed on the CaF2/oleate, A1203/SDS and KC1/...Oleates; Micellar; In situ analysis; Adsorption1993
139 Miller, Jan D.Surfactant adsorption density calculation from Fourier transform infrared external reflection spectroscopy (FTIR/ERS)An equation to calculate surfactant adsorption density from Fourier transform infrared external reflection spectra was established. The derivation and limitation of this equation are discussed in detail. The validation of the FTIR/ERS adsorption density equation was experimentally verified from t...Surfactant; Adsorption density; Solid film2003
140 Miller, Jan D.Synthesis of DME from CO₂/H₂ gas mixtureThe activity and durability of two hybrid bifunctional dimethyl ether (DME) synthesis catalysts: 6CuO-3ZnO-Al2O3/ƴ-Al2O3 and 6CuO-3ZnO-1Al2O3/HZSM-5, have been evaluated for the conversion of CO2/H2 to DME at 260oC, 5 MPa, and gas per hourly space velocity (GHSV) of 3000 mL gcat -1 h-1 in fixed-bed...2011-01-01
141 Miller, Jan D.Tar sand pretreatment with diluentImportant aspects of kerosene penetration into tar sand have been investigated. The natural tar sand porosity was measured and used to analyze the performance of the hot water process. Subsequently, pretreatment experiments, using 20-kg tar sand samples (Asphalt Ridge and Whiterocks, Utah) and ker...Tar sand; Kerosene; Porosity; Temperature1993
142 Miller, Jan D.Thermogravimetric/Mass spectrometric (TG/MS) characterization of toner particles from photocopied wastepaper and the impact of these features on flotation deinkingFlotation deinking of photocopies from office waste is known to be much more difficult than the flotation deinking of newsprint. In this regard, research has been undertaken to better understand the phenomena which account for the poor efficiency in the flotation deinking of such office waste. Durin...Photocopied paper; Recycling; Deinking; Flotation; Thermal decomposition; Thermogravimetry; Mass spectrometry; Differential scanning calorimeter; Toner particles1995
143 Miller, Jan D.Thiocarbonate collectors in pyrite flotation ? fundamentals and applicationsRecent results from electrochemical measurements demonstrate that trithiocarbonate (TTC) collectors are more readily oxidized to their corresponding dithiolates than the dithiocarbonate/xanthate (DTC) collectors. Based on the traditional analysis of collector adsorption, trithiocarbonates might then...Trithiocarbonate; xanthate; nitrogen2003
144 Miller, Jan D.Thiourea-thiocyanate leaching system for goldThe leaching of gold in thiourea-thiocyanate solutions has been studied by the rotating-disk technique using ferric sulfate as oxidant. The effects of initial concentrations of ferric, thiourea (Tu) and thiocyanate as well as temperature and pH values on gold leaching rates were studied. An initial ...2010-01-01
145 Miller, Jan D.Three dimensional analysis of particulates in mineral processing systems by cone beam X-ray microtomographyIn general, X-ray-computed tomographic (CT) techniques are capable of providing three-dimensional images of the internal structure of opaque materials in a nondestructive manner. The unique cone beam geometry allows acquisition of all two-dimensional projections with only one rotation of the sample,...Cone beam CT; X-ray microtomography; Liberation analysis; Particle shape; Heap leaching; Exposure analysis; Coal washability2004
146 Miller, Jan D.Toner ink particle morphology in air-sparged hydrocyclone flotation deinkingA series of pulping and flotation deinking tests were performed using a pilot-scale air-sparged hydrocyclone (ASH) flotation cell and a toner ink printed furnish. Microscopy studies indicate ink particles in both the flotation accepts and rejects are relatively flat. Many of the ink particles ap...Elongation; Cyclone; Particles1996
147 Miller, Jan D.Treatment of cyanide by using the Mexican modification of the Merrill-Crowe processCyanide consumption can be a major factor which contributes to operating cost for cyanidation. Also after extraction and recovery of precious metals substancial amounts of cyanide are delivered to tailings ponds which creates environmental problems due to the toxicity of cyanides. In this regard, th...Cyanidation; Merrill-Crowe process; Air-sparged hydrocyclone; Cyanide recovery; Cyanide destruction; Chlorine dioxide1999
148 Miller, Jan D.Trithiocarbonates for PGM flotationSmall replacements of C12-trithiocarbonate (C12-TTC) for dithiocarbonate DTC)/dithiophosphate (DTP) in a reagent suite for the flotation of platinum group metals (PGM) have significantly improved the rejection of gangue. Coupled to this is an improvement in kinetics, grade and recovery of PGMs. In ...2006
149 Miller, Jan D.Understanding the agglomeration behavior of nickel laterite and gold ores using statistical design of experimentsThe drum agglomeration of nickel laterite and gold ores has been optimized through the design of experiments (DOE) using a Taguchi L16 (45) orthogonal array to determine the optimum conditions for maximizing average agglomerate size and minimizing the amount of fines. The effects of controllable ope...2014-01-01
150 Miller, Jan D.Understanding the role of ion interactions in soluble salt flotationThere is anecdotal evidence for the significant effects of salt ions on the flotation separation of minerals using process water of high salt content. Examples include flotation of soluble salt minerals such as potash, trona and borax in brine solutions. Although some of the effects are expected, so...2011-01-01
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