Table of Contents Results of this investigation demonstrate that high-purity columbium and tantalum compounds can be obtained by application of the solvent extraction separation system: Hydrofluoric acid-sulfuric acid-methyl isobutyl ketone. This system is unique in that it not only separates columbium from tantalum, but separates these two metals from other metallic impurities. The system is … Read more
Table of Contents The experimental blast furnace has attracted increasing interest during the past decade as a practical means for investigating a broad range of blast-furnace smelting problems. Under experimental-furnace conditions, information can be obtained with less expenditure of time and raw materials and, therefore, at lower cost than comparable information could be obtained under … Read more
Table of Contents The precipitate method described herein is advantageous because of its rapidity and relative simplicity. This method eliminates the standardization of reagents, second filtration, washing of precipitate, and dissolving of ammonium phosphomolybdate precipitate, all of which are required in the titration step of the usual alkalimetric method. The precipitate method does not approach … Read more
Table of Contents Construction of a 250-p.s.i.g. helium-recycle system to operate with gas temperatures as high as 2,500° F. appears feasible. More development work is required, however, on heat exchangers and compressors. Many problems inherent in large nuclear systems are not present in the pilot-scale ISR system. Although the cooler in the ISR loop operated … Read more
Table of Contents A simplified, routine method for determining lithium in lithium-bearing rock is presented. The sample is decomposed by repeated treatments with nitric, hydrofluoric, and perchloric acids. Since this procedure does not appreciably dissolve beryl, interference by beryllium (the principal interfering cation) is minimized for most samples. The salts are brought into solution with … Read more
Table of Contents This is one of a series of reports prepared by the Federal Bureau of Mines on mining methods, performance, and costs at individual mines in the United States. The primary purpose of these papers is to promote development and conservation of our mineral resources by disseminating technological information on methods, practices, and … Read more
Table of Contents Because an economic method for preparing pure boron has not been developed, a program was started by the Bureau of Mines to evaluate existing techniques or to develop new methods for preparing the pure element. This report describes investigations directed toward the development of techniques for the preparation of pure boron by … Read more
Table of Contents Crude Minnesota taconite was charged in the Bureau of Mines experimental blast furnace so that smelting characteristics of such highly siliceous raw materials could be studied and smelting costs compared with those of a standard Mesabi ore. The Bureau recognized that the highly siliceous nature of the crude ore and its relatively … Read more
Table of Contents This report describes the preparation of tritium-labeled organic compounds to be used by the Federal Bureau of Mines in studying the role of certain gasoline constituents in gum-forming mechanisms. The gasoline constituents that have been investigated boil within a range of approximately 90 to 230° C. and can be classified as paraffins, … Read more
A spectrophotometry method for the determination of small amounts of copper in tungsten metal powder using the principle of solvent extraction has been developed. The metallic sample is dissolved in hydrogen peroxide, tartaric acid added, the pH adjusted, and the excess peroxide destroyed by boiling. Copper is reduced to the cuprous state, and the reagent … Read more