Dispersion Strengthened Copper
In accordance with a program for developing new materials required for emerging technologies, an investigation was undertaken to determine the properties of dispersion-strengthened copper. The copper contained either alumina or yttria as a dispersoid and was prepared by coprecipitation-a potential method for commercial production. Although the coprecipitation method had been used previously to prepare dispersion-strengthened […]
Solvent Extraction of Nickel and Zinc
Solvent extraction of a waste solution from the phosphating of automobile bodies led to the following conclusions: Separate zinc, nickel, and phosphate products, essentially free of each others were produced. Zinc was 99 percent extracted by di-2-ethylhexyl phosphoric acid in kerosene, and nickel was 99 percent extracted by dinonyl naphthalene sulfonic acid in butyl ether. […]
Scrap Tire Distillation
Destructive distillation was demonstrated to be a technically feasible method of disposing of and obtaining potentially valuable products from scrap automobile and truck tires. The relative amounts of the various products were shown to be highly dependent on the temperature of carbonization. Highest yields of liquid products were obtained at 500° C and highest yields […]
How to Stabilize Uranium Tailings
An environmental radiological survey was conducted on the El Paso Natural Gas Co. uranium tailings pile at Tuba City, Ariz., in May 1967, by the South-western Radiological Health Laboratory of the Public Health Service, U.S. Department of Health, Education, and Welfare (HEW). As the abstract of the reports of the survey summarizes the pertinent facts […]
Silver Chloride & Silver Bromide Thermodynamic
Adequate values for the standard heats and entropies of formation of silver chloride and silver bromide are available. However, thermodynamic calculations involving these substances have been hampered by the lack of accurate high-temperature enthalpy and entropy data. The enthalpy and heat capacity results reported in the literature are fragmentary and conflicting. As part of a […]
Recover Metals from Electroplating Wastes
The waste-plus-waste treatment method can be successfully used on a variety of acid and alkaline electroplating wastes. The method is economically attractive because of the low cost of the waste-plus-waste addition step: No additional reagents are necessary, and the metal values are concentrated. In the five waste-plus-waste combinations investigated, combination of the two wastes caused […]
Convert Hydrous Calcium Sulfate to Hydrogen Sulfide
During the period 1960-65 sulfur consumption in the United States rose 40 percent to 7.96 million long tons. Since 1963, while demand has exceeded production, withdrawals from producer stocks have met the deficit. An assured steady supply of sulfur is essential for the national interest. Its applications are so diverse that the quantity used is […]
How to Measure Surface Tension of Molten Metals
We been performing research on soft soldering with the objective of improving the strength of solder joints at elevated temperatures and pressures. Surface or interfacial phenomena and the factors affecting these phenomena are of major importance in soldering and brazing. A knowledge of the surface tension of the molten materials involved, such as the filler […]
Chalcocite Oxidation Roasting
The Bureau of Mines Twin Cities Metallurgy Research Center is engaged in a study to uncover a cleaner, more direct pyrometallurgical process for winning copper from sulfides. The .initial target is low-sulfur concentrates containing primarily chalcocite (Cu2S). Development work, still in progress, points to a new and, perhaps, improved smelting procedure in which the following […]
How to Evaluate Face Respirator Fit
For the past few years there has been increasing interest among respirator users in determining quantitatively the degree of protection afforded by protective respiratory devices. Overall protection depends on both the efficiency of filters and/or sorbents used and the tightness of seal around the edges of the facepiece. The Bureau of Mines first introduced quantitative […]