Meet CMI Researcher Scott Herbst

CMI researcher Scott Herbst is the deputy lead of Focus Area 1 Diversifying Supply. In this role, he assists Dr. Moyer with these important projects that will expand the variety of source materials, increase processing efficiency, and find new uses for the abundant non-critical rare earths. Dr. Herbst is a Chemical Engineer at the Idaho National Laboratory (INL) and has well over 20 years experience in nuclear fuel reprocessing, separation process chemistry and engineering, and development of new separation methods based on solvent extraction and ion exchange. With well over 100 publications and several patents in the field of chemical separations and nuclear waste processing, he is a recognized separation expert in the DOE, industrial, university, and international communities with extensive experience in the development of separation technologies for the treatment of radioactive wastes, spent nuclear fuel, hazardous and mixed wastes.

Dr. Herbst has been, or currently is, the Principle Investigator on numerous national and international research and development projects in solvent extraction. Synergistic activities include providing technical support for the nuclear Fuel Cycle R&D (FCR&D) program, primarily in the areas of actinide, lanthanide, and fission product chemistry and separations from Generation IV reactor fuel. His separations expertise has covered a diverse group of elements such as uranium, plutonium and other actinides, the fission products, hazardous metals such as Hg, Cr, and Pb, transition metals Zr and Fe, the lanthanide elements, and the difficult separation of boron isotopes. He has a broad background in developing and designing separations flowsheets via the combination of experimental and computer modeling techniques.  In addition, he has a great deal of experience in testing flowsheets in laboratory and pilot-scale separations equipment including centrifugal contactors. Recent efforts have focused on separation flowsheets in conjunction with the industrial separation and purification of the lanthanide elements.

Expertise in selective radionuclide partitioning has been applied to an R&D program to develop selective partitioning strategies and flowsheets for recovery of select isotopes in accord with the US efforts in the former Advanced Fuel Cycle Initiative. This work resulted in demonstration of numerous technologies, including the cobalt dicarbollide/PEG-400 process for selective removal and recovery of the fission products Cs-137 and Sr-90. Flowsheets were developed and tested in counter-current mode using centrifugal contactors on samples of actual and simulated solutions of dissolved spent nuclear fuel.

Experience includes electrochemical reprocessing of spent nuclear breeder reactor fuels at Argonne National Laboratory, where he developed multi-component material balance methodologies for portions of the electrorefining process and participated in the metallurgy, casting, blending, and accountability portions of the flowsheet preparing the highly enriched uranium (HEU) product from the electrorefining operation for final disposal as low enriched uranium product.

Dr. Herbst received his bachelor of science degree in chemistry from Idaho State University in 1984 and his master of science and doctorate degrees in chemical engineering from Montana State University in 1989 and 1992, respectively. Currently, he is a contributor on a wide range of Department of Energy and other U.S. government programs.