Extrapolation of world energy consumption from 1990 to 2008 will result in the complete exhaustion of world reserves of oil, natural gas, uranium and coal until 2040, 2046, 2048 and 2054, respectively. For the survival of all people in the whole world, intermittent and fluctuating electricity generated from renewable energy should be supplied in the form of usable fuel to all people in the whole world. We are proposing global carbon dioxide recycling for the use of renewable energy in the form of methane via electrolytic hydrogen generation using carbon dioxide as the feedstock. We created energy-saving cathodes for hydrogen production, anodes for oxygen evolution without chlorine formation in seawater electrolysis and catalysts for methanation of carbon dioxide and built the pilot plants of industrial scale. Recent advance in materials is described. The industrial application is in progress.
In secondary systems of several pressurized water reactor (PWR) plants, operation conditions under a high pH in the presence of ammonia or ethanolamine (ETA) have been used, and the suppression of corrosion has been reported. In PWR secondary systems, Cu alloys have been used for some of the structural components. Accordingly, it is necessary to investigate the corrosion behavior of these Cu alloys under high pH conditions. In the present paper, the corrosion behavior of Cu alloys in NH3 and ETA solutions was investigated under conditions simulating the condensate water, feed water, and main steam systems. The effects of corrosion on the integrity of the alloys were determined by a tensile test. The corrosion of the copper alloys was accompanied with the formation of oxide in the solution containing dissolved oxygen at 70°C. On the other hand, the selective dissolution of additional elements was observed in the solution without dissolved oxygen at 220 and 280°C. There was no apparent difference in the corrosion behavior of Cu alloys in NH3 solution and ETA solution. The corrosion rate of the Cu alloys increased with the Pb content in the alloys. Effects of the corrosion during the immersion test on tensile properties of Cu alloys were not observed.