The Sulfur-Iodine (S-I) thermochemical cycle is one of the baseline production methods that is being investigated under the Department of Energy's Nuclear Hydrogen Initiative (NHI). The current objective is to conduct an integrated lab scale (ILS) experiment in order to provide a technical basis for the assessment of the viability of the S-I cycle for nuclear hydrogen production.

The development of the S-I cycle ILS loop has been performed as an international effort involving the US Labs and Industry and the Commissariat à l'Énergie Atomique (CEA) of France. The S-I cycle consists of three reaction sections which are currently being developed by three different organizations. Sandia National Laboratory (SNL) is developing the high temperature sulfuric acid decomposition section, General Atomics (GA) is developing the HI decomposition (hydrogen generation) section, and the CEA is developing the primary Bunsen reaction section. Work has been ongoing in all three organizations for the past five years and has resulted in experiments on the initial stand-alone versions of the reaction sections. These three sections have been integrated into the ILS experiment at the General Atomics facility in San Diego. This paper will describe the status of the ILS system and experiments.