caa a22 4500 388021284 CHVBK 20180307124925.0 cr unu---uuuuu 161130e199801 xx s 000 0 eng 10.1557/JMR.1998.0010 doi S0884291400042473 pii (NATIONALLICENCE)cambridge-10.1557/JMR.1998.0010 Alternative reagent to mercuric nitrate catalyst for dissolution of aluminum-clad nuclear fuels in nitric acid [Elektronische Daten] A substitute additive, HBF4, has been discovered that will replace Hg(NO3)2 catalyst for dissolving aluminum spent nuclear fuels in nitric acid for recovery of usable materials. The catalyst or substitute is necessary to penetrate a protective oxide film that continuously forms on the Al surface in the oxidizing acid. A penetration rate of alloy Al-6061 T6 of 40 mg/cm2-h can be achieved in a continuous dissolution process at 100 °C using a dissolvent of 0.15 M HBF4 in 7 M HNO3 that achieves a steady-state composition of 1.0 M Al3+ and 3.3 M HNO3, while maintaining a corrosion rate of a type 304L stainless steel dissolver vessel of 0.015 mm/mo. The penetration rate of aluminum is correlated with the equilibrium concentration of HF in the system. The postulated mechanism involves dissolution of the alumina film by approximately 0.006 M HF in equilibrium with the HBF4 and complexed aluminum fluoride species in nitric acid, which provide a large semi-buffered supply of HF. This allows the HNO3 to attack the aluminum metal. The small concentration of HF does not compete favorably with HNO3 for reaction with and consumption by Al. Copyright © Materials Research Society 1998 Anderson Philip A. Lockheed Martin Idaho Technologies Company, Idaho National Engineering and Environmental Laboratory, Idaho Falls, Idaho 83415 Christian Jerry D. Lockheed Martin Idaho Technologies Company, Idaho National Engineering and Environmental Laboratory, Idaho Falls, Idaho 83415 Journal of Materials Research Cambridge University Press 13/1(1998-01), 68-76 0884-2914 13:1<68 1998 13 JMR https://doi.org/10.1557/JMR.1998.0010 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1557/JMR.1998.0010 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Anderson Philip A. Lockheed Martin Idaho Technologies Company, Idaho National Engineering and Environmental Laboratory, Idaho Falls, Idaho 83415 NATIONALLICENCE 700 1- Christian Jerry D. Lockheed Martin Idaho Technologies Company, Idaho National Engineering and Environmental Laboratory, Idaho Falls, Idaho 83415 NATIONALLICENCE 773 0- Journal of Materials Research Cambridge University Press 13/1(1998-01), 68-76 0884-2914 13:1<68 1998 13 JMR CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-cambridge