Castable cements to prevent corrosion of metals in molten salts

Journal Article · Fri Apr 22 00:00:00 EDT 2016 · Solar Energy Materials and Solar Cells

DOI: https://doi.org/10.1016/j.solmat.2016.04.009 · OSTI ID:1252170

Gomez-Vidal, Judith C. ^[1]; Morton, E. ^[1]

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1. National Renewable Energy Lab. (NREL), Golden, CO (United States)

Castable cements on metals form a protective barrier that is able to prevent permeation of molten salts towards metallic surfaces. Silica-based castable cements are capable of protecting containment metallic alloys from the corrosive attack of molten chlorides at temperatures as high as 650 °C. Boron nitride (BN) blocking the pores in the cured cement prevents permeation of the molten chloride towards the metal surface. The cements tested are not chemically stable in molten carbonates, because the bonding components dissolved into molten carbonates salt. The corrosion rate is 7.72±0.32 mm/year for bare stainless steel 347 in molten eutectic NaCl – 65.58 wt% LiCl at 650 °C, which is the baseline used for determining how well the cement protects the metallic surfaces from corrosion. In particular the metal fully encapsulated with Aremco 645-N with pores filled with boron nitride immersed in molten eutectic NaCl – 65.58 wt% LiCl at 650 °C shows a corrosion rate of 9E-04 mm/year. Here, the present study gives initial corrosion rates. Long-term tests are required to determine if Aremco 645-N with BN coating on metal has long term chemical stability for blocking salt permeation through coating pores.

• Research Organization: National Renewable Energy Lab. (NREL), Golden, CO (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Solar Energy Technologies Office (EE-4S)
• Grant/Contract Number: AC36-08GO28308
• OSTI ID: 1252170
• Report Number(s): NREL/JA--5500-64723
• Journal Information: Solar Energy Materials and Solar Cells, Journal Name: Solar Energy Materials and Solar Cells Journal Issue: C Vol. 153; ISSN 0927-0248
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English