R&D of Co-free hydrogen production technology using thermochemical water-splitting iodine-sulfur process

Kubo, Shinji  ; Takegami, Hiroaki ; Tanaka, Nobuyuki ; Noguchi, Hiroki  ; Kamiji, Yu; Myagmarjav, O.  

A thermochemical water-splitting iodine-sulfur (IS) process offers the potential for the mass production of hydrogen at high levels of efficiency. A test facility for producing hydrogen was constructed from corrosion-resistant chemical reactors. In this paper, engineering solutions for stable hydrogen using this facility are describes. Technical issues hindered stable hydrogen production included the unstable operation of the HI-I solution pump, leakage of corrosive solution owing to the breakage of glass lining equipment, pipe clogging owing to solid iodine precipitation in the HI-I solution, and unstable plant conditions in startup operation to make the closed-cycle. These technical issues were solved and were incorporated into the test facility, the entire process was successfully operated for 150 h at the rate of ca. 30 L/h.