Comparison of a Modified Kjeldahl and vacuum Fusion Techniques for Determination of Nitrogen in Tantalum Alloys

Abstract

This report compares results obtained for the determination of nitrogen in the tantalum-base alloys T-111 and T-222 by Kjeldahl and vacuum fusion procedures. The Kjeldahl method used consists of a rapid decomposition with HF-H3PO4-K2CrO4 followed by the highly sensitive colorimetry of nitroprusside-catalyzed indophenol. The vacuum fusion procedure described uses a platinum-tin bath, platinum flux technique. In the 5 to 25 ppm range, the relative standard deviation was 3 to 9 percent by the Kjeldahl procedure and 4 to 8 percent by vacuum fusion. The agreement of the nitrogen results by the two techniques is considered satisfactory.

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Document Details

Document Type
Technical Report
Publication Date
Jul 01, 1970
Accession Number
ADA277724

Entities

People

  • Emery J. Merkle
  • Judson W. Graab
  • Warren F. Davis

Organizations

  • National Aeronautics and Space Administration

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Acid-Base Indicators
  • Acids
  • Air Pollution
  • Alloys
  • Boric Acids
  • Chemical Laboratories
  • Cold Water
  • Materials
  • Measurement
  • Metals
  • Niobium
  • Refractory Metal Alloys
  • Refractory Metals
  • Rings
  • Sodium Compounds
  • Tantalum
  • Tantalum Alloys

Readers

  • Analytical Chemistry
  • Surface Engineering/Surface Coating Technology.