Abstract: A droplet impact sampler based upon the stain technique for measuring airborne droplets comprises a magnesium oxide coated, graphite target located within a cylindrical sampler head below a pneumatically operated shutter. The shutter is opened for a predetermined time period to expose the target to the specimen droplets which stain the target upon contact. Droplet size is determined by measuring the stain diameters and compensating for a flattening effect of the droplet that occurs upon impact as a function of several parameters, such as contact angle, water density and surface tension. Rate of deposition is determined by correlating the number of stains counted on the target with the operating speed of the shutter.

Abstract: Aluminum nitrate solutions are subjected to hydrolysis at elevated temperature and pressure, with the pressure being kept relatively low by continual bleeding of reactant gases from the reaction vessel. The resultant product is a noncrystalline alumina that may be readily converted to crystalline alumina by roasting.In addition, the discharged reactant gases are employed for leaching of clay to provide aluminum nitrate feed solution.

Abstract: AlCl.sub.3.6H.sub.2 O is decomposed at a temperature above about 700.degree. C. in the presence of hydrogen to form an alumina product having a very low residual chlorine content.

Abstract: To recover chromium from scrap such as superalloy scrap, the feedstock is melted, subjected to controlled oxidation to oxidize and slag off reactive metals, then subjected to sulfidation and slow cooling to produce a coarse-grained solid wherein the bulk of the chromium is present in a phase consisting predominantly of a chromium sulfide.

Abstract: There is disclosed a process for recovering nickel (II), copper (II) and cobalt (II) from an ammoniacal-ammonium sulfate leach liquor. This process includes the step of adjusting the pH of the leach liquor prior to co-extracting the nickel and the copper values. Cobalt is recovered as cobalt (II) by reduction of cobalt (III) to cobalt (II) following by an extraction step.

Abstract: A low cost, effective method for removing heavy metal ions from aqueous solution which utilizes a porous, high surface-to-weight ratio siliceous adsorbent comprises the steps of activating the siliceous adsorbent, which is preferably a kaolin clay leach residue, with a basic salt of an alkali metal to incorporate alkali ions into the siliceous adsorbent and contacting the heavy metal ion-containing solution with the activated adsorbent whereby the heavy metal ions exchange with the alkali ions to remove the heavy metal ions from solution. The heavy metal ion loaded adsorbent may be stripped for subsequent reuse or, alternatively, utilized for flux in base metal smelting and the like.

Abstract: A rapid, energy efficient, low cost, nonhazardous method for the selective removal of mercury from mercury-containing metal cyanide solutions, particularly the cyanide solutions resulting from the cyanidation of gold ore and the like, wherein a reactive sulfide is admixed with the solution for a time sufficient to form an insoluble mercuric sulfide precipitate. The mercuric sulfide precipitate is then separated from the metal cyanide solution by filtration or other conventional means.

Abstract: Percolation leaching of gold or silver ores, tailings or wastes is accomplished by a process comprising initial agglomeration of fines in the feed by means of a binding agent and cyanide solution, followed by aging and, subsequently, leaching to recover gold or silver values.

Abstract: Exhausted Cr.sup.+6 oxidizing solutions containing Cu.sup.+2 values are electrolyzed by placing an exhausted Cr.sup.+6 etching or oxidizing solution containing copper ion and Cr.sup.+3 ions in an electrolytic cell containing at least one pair of carbon particle electrodes, and forcefully flowing the exhausted solution through the electrodes and simultaneously impressing a direct current across the electrodes such that at the cathode divalent copper is reduced to copper metal and Cr.sup.+6 values are reduced to trivalent chromium and at the anode water is oxidized to oxygen.

Abstract: Highly active catalysts, suitable for use in hydrogenation and other reactions, are prepared from an alloy of one or more of the Group VIII transition metals with yttrium or a rare earth metal. The alloy is ground to the desired particle size and is thereafter reacted with a gas containing carbon monoxide and hydrogen to form an intimate physical admixture of the Group VIII metal or its corresponding carbide with the oxide of yttrium or the rare earth metal.

Abstract: A cement composition comprising a high calcium-content fly ash and calcium sulfate, and mortar and concrete compositions containing the cement.

Abstract: Percolation leaching of gold or silver ores, tailings or wastes is accomplished by a process comprising initial agglomeration of fines in the feed by means of a binding agent and water, followed by aging and, subsequently, leaching to recover gold or silver values.

Abstract: A chainless haulage system having at least three pairs of sprocket wheels, each pair disposed on a separate axle with opposed wheels on each axle aligned in a pair of parallel planes. Two pairs of sprocket wheels are disposed laterally offset from each other and serve as follower sprocket wheels, while a third pair is driven by conventional means. A pair of endless drive chains each having adjacent chain links in generally perpendicular planes respectively engage sprocket wheels disposed in the parallel planes to form a double strand of drive chain. The two endless drive chains are interconnected by a plurality of crossbars, each of which is formed of a pair of opposed chain links integrally connected by a connecting bar, the chain links of the cross bar inserted in series with the links of the endless drive chain. A hollow cylindrical roller is loosely disposed around the connecting bar of the cross bar.

Abstract: In an in situ uranium leaching process, a method of detecting presence or absence of leach solution escaping from a desired leaching zone involves monitoring the electrical impedance of a zone just outside the desired zone to detect high ionic concentration indicative of leach solution. Electrical impedance is measured by locating monitor wells just outside the leaching zone and positioning pairs of current and voltage probes within the monitor wells and closest injection wells. Low frequency, constant current is generated by each pair of current probes between corresponding injection and monitor wells to develop a zone impedance-dependent voltage drop that is measured by each set of voltage probes and correlated to presence or absence of escaping leach solution. In an alternative embodiment, electrical impedances are measured between a single, central recovery well and a series of distributed, monitor wells to reduce the total number of probes required.

Abstract: A method of augmenting the cutting operation of a cutter bit to reduce the cutting energy required and to reduce the respirable dust generated during the cutting operation. During the cutting operation of coal with a continuous mining machine greater than 90 percent of the primary respirable dust generated occurs in the crushing zone around the tip of bit. By applying a high pressure (2,500 to 5,000 psi) spray of water at or near the center of the cutting tip, as the tip touches the coal, tests have shown very substantial reductions in the airborne respirable dust generated and that there is lubrication and cooling at the cutter tip/mineral interface to provide for reduced sumping forces and lowered methane ignition potential.

Abstract: An improved method of in situ mining of a mineral bearing stratum. The method comprises drilling alternating rows of vertical injection and recovery wells to the depth of an aquiferrous mineral bearing stratum. Two horizontal branches are drilled at the bottom of each injection and recovery well. The horizontal branches are substantially parallel to one another and lie within the mineral bearing stratum. Leachant fluid is pumped under pressure into the injection wells to dissolve the minerals contained in the stratum. Leachant fluid containing the dissolved minerals is pumped out through the recovery wells. The method of the present invention requires substantially less drilling and pipe for extracting minerals from a given volume of a mineral bearing stratum and results in more constant mineral extraction rates than conventional techniques.

Abstract: An extensometer anchor for use in a mine borehole. The anchor has an anchor body that, when in an operative mode, is placed in the borehole. Extending at least partially around the outer surface of the body are one or more grooves whose major plane is generally perpendicular to the length of the borehole. Seated within each groove is a compressible resilient anchor member, like a ring, which remains loaded by a retaining device, such as a cotter pin, extending through it. Upon being pulled from outside of the borehole, the retaining device unloads the compressed anchor which then moves to expand outwardly in the borehole and firmly anchor the anchor body and attached extensometer within the mine borehole.

Abstract: There is disclosed, in a process for separating zirconium and hafnium, an improvement for the removal of sodium sulfate from a sulfate-containing sodium chloride solution. This improvement includes adding a water-miscible organic precipitant such as methanol, ethanol or acetone to the sulfate-containing sodium chloride solution. The precipitant is added in an amount sufficient to cause the removal of sulfate as sodium sulfate. The organic precipitant is removed and the substantially sulfate ion free sodium chloride solution is recycled. Also provided is a process for the recovery of sodium sulfate having a purity greater than 99.9%.

Abstract: An electrolytic stripping cell is provided which is particularly adapted for use in processing shredded, silver brazed, stainless steel honeycomb scrap. The cell comprises a mesh anode basket which rotates within a cathode cylinder to provide partial stirring of the cell electrolyte. The anode basket includes a central hollow shaft having holes therein through which the electrolyte continually circulates. The basket includes wiper blades for dislodging silver dentrites which grow between the anode and cathode and which, as they fall, are collected in a mesh basket located at the bottom of the cell housing.

Abstract: An 8-hydroxyquinoline-resorcinol-formaldehyde ion exchange resin, in bead form, is employed for sorption of tungsten from alkaline solutions such as brines.