'A method for the prevention of corrosion and hydrogen - embrittlement prepared from tantalum devices in which hot concentrated sulfuric acid is handled'

摘要

PURPOSE:To prevent the corrosion of apparatus made of Ta and usable for handling hot concd. sulfuric acid and remarkably prevent the hydrogen embrittlement thereof in particlular by adding an oxidizing agent soluble in hot conc. sulfuric acid to the acid. CONSTITUTION:An oxidizing agent soluble in hot concd. sulfuric acid is added to the acid of 200-300 deg.C used for decomposing radioactive resin or org. matter-contg. radioactive sludge discharged especially from nuclear powr facilities, thus preventing the corrosion and hydrogen embrittlement of apparatus such as towers, vessels, heat exchangers, piping and instruments made of Ta. Nitric acid, gaseous nitric acid or metal (II) ion of Fe, Cu, Sn or Pb is used as the oxidizing agent. When nitric acid is used as the agent, the acid is required to exist 0.001- about 4wt% in concd. sulfuric acid at all time.