The U.S. Department of Energy (DOE) is seeking Expressions of Interest (EOI) for the Molten Salt Reactor Experiment (MSRE) secondary side coolant salt, targeting universities, companies, or organizations interested in its applications in nuclear reactor technology. The DOE aims to gather insights on potential uses of the FLiBe salt, which was produced during the MSRE operations from 1965 to 1969, and is now available for experiments or reactor operations, emphasizing the importance of advanced reactor technology and molten salt reactors (MSRs). Interested parties must submit their proposals via email, detailing their intended uses, benefits to the U.S. nuclear industry, and any technical challenges, while noting that the DOE will not provide funding for material acquisition or processing. For inquiries, contact the Department of Energy at EOIMSRESecondarySaltQuestions@doe.gov.