Corrosion tests were run concurrently at Location A and Location B to determine the effects of ferric ion \[Fe(III)\] content on inhibiting general corrosion of titanium Grades 2 (UNS R50400), 7 (UNS R52400), 12 (UNS R53400), 16 (UNS R52402), 27 (UNS R52254), and 28 (UNS R56323) in hydrochloric acid (HC1) solutions at 66-282°C. Tests were conducted at Location A with 1,000 and 10,000 ppm Fe(III) additions to boiling HCI solutions to establish 5 mpy isocorrosion diagrams as an extension of previous work (~). Location A tests also assessed the effects of higher temperatures (282°C) on the corrosion performance of titanium Grades 2 and 7 in HCI solutions with 10,000 ppm Fe(III) additions. Location B tests were performed to evaluate the corrosion resistance in 66°C, 82°C, and boiling HC1 solutions at concentrations up to 35 wt.% and Fe(III) additions up to 28,000 ppm. The comprehensive alloy corrosion database developed is applicable to many chemical process streams such as hydrometallurgical acid ore leaching (2), acid cleaning of deep wells and other chemical processes involving Fe(III) and other multivalent metal ions.
Keywords: Titanium, ferric ion, corrosion inhibition, hydrochloric acid