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The cost reduction of hydrogen stations is a must in order to spread fuel cell vehicles. Generally, the PSA device in the hydrogen station occupies 30% of the construction cost. We have already proposed the cost reduction by replacing the PSA and CO shift converter with a membrane reactor to which CO2 selective facilitated transport membrane is built in 2011. Although the CO2 facilitated transport membrane achieved the CO2/H2 selectivity of 100 or more even if the operation temperature was 160°C, the durability was poor. Therefore, it is necessary to improve the heat resistance and the rate of reaction between carrier and CO2 furthermore so that it can be adopted for the membrane reactor. In order to improve the membrane performance at 160°C by keeping high water content of membrane, graphite rubbish was added to the membrane as it was expected to function as grain for water absorption. As a result, the CO2 selectivity of the membrane improved more than that of the previous membrane by 3 times.

The hydrogen station in Japan is only 17 points though Toyota began to sell FCV from 15th November, 2014. The main reasons for which the spread of HS is late are a high construction cost and the indefinitely of spread prospect of FCV. However, it became clear that FCV in Japan spreads surely because the order for FCV exceeded 1000 from release in one week. The remaining problem is to reduce the cost of construction of 300 million yen. Therefore, we proposed membrane reactor composed of the reformer and the CO2 facilitated transport membrane to reduce the construction cost. It is necessary to achieve heat resistance of 160°C so that it is adopted for the membrane reactor. Therefore, we aim to optimize the operating condition (humidity, partial pressure of CO2 and differential pressure) of NDP to obtain the indicator of the heat resistance improvement at first. As a result, it is clear that the optimum operating condition of NDP is 80% of relative humidity, 200kPaG of the differential pressure and 40kPaG of the CO2 partial pressure.