A study on enrichment and volume reduction of tritiated water in a fusion reactor using photocatalysis

为了促进聚变反应堆的安全和公众的接受，建立一个浓缩或减少氚水体积的安全程序是很重要的。在容器中临时储存氚水不是最后的措施。水蒸馏需要很大的能量，而且有一个经济问题。光催化二氧化钛(锐钛矿型)有望分解空气污染物，将水分解为氢和氧。由于轻水和重水或氚水的离解能可能有微小的差异，因此利用光催化剂对聚变反应堆排放的废水中氚的浓缩进行了实验研究。在本研究的第一年，我们采用非电解镀金的方法在不同的温度和浓度条件下制备了光催化剂。在二氧化钛表面镀镍制成催化剂，然后在玻璃池中浸泡在水中的光催化材料置于…下氙灯发出更多的紫外光。部分氚水在锐钛矿光催化作用下解离为氢和氧，并在氧化镍上复合。氚水和轻水的解离和复合速率不同，使未解离水中的氚有一定的富集性。由于光催化富集氚水的关键是制备高效的催化剂，因此在不同的镀膜条件下对多种催化剂进行了测试。虽然钛的氧化物和镍的氧化物是有效的，但产量相对较小。因此，在本研究的第二年，在氯化钯溶液中进行了另一种非电解镀金的试验。在紫外光下研究了锐钛矿钯催化剂对氚的富集性。产率提高，同位素分离因子在1.1左右。为了将本方法应用于工业规模，必须使固体(催化)、液体(水)和气体(蒸汽、氢气和氧气)之间有良好的接触。为了保持良好的接触，我们发现滴流床系统是最佳的。得出的结论是，在下一步的研究中应对滴流系统进行研究。部分结果已在科学期刊上发表，其余结果将在不久的将来公布。较少

It is important to establish a safety process of enrichment or volume reduction of tritiated water for promoting safety of a fusion reactor and public acceptance.Tentative storage of tritium water in a vessel is not final measures. Water distillation needs a large energy and has an economical problem. Titanium oxide (anatase) of photocatalysis is expected to decompose air pollutantor to dissociate water into hydrogen and oxygen. Since there may be a small difference in dissociation energy between light water and heavy or tritiated water, enrichment of tritium in waste water expected to be exhausted from a fusion reactor was experimentally investigated by using a photocatalysis.In the first year of the present research, we manufactured photocatalyses by means of nonelectrolysis gilding under different conditions of temperature and concentration. The catalysis was manufactured by plating nickel oxide on titanium oxide.Then the photocatalysis dipped in water in a glass cell was put undera … More n ultraviolet light from a xenon lamp. Part of tritiated water dissociated to hydrogen and oxygen on the anatase photocatalysis, and they recombined on nickel oxide. A difference in rate of dissociation and recombination between tritiated water and light water brought a certain enrichment of tritium in non-dissociated water. Since a key to enrich tritiated water by photocatalysis is to manufacture a high-efficient catalyst, many catalyses were tested under various plating conditions. Although.titanium oxides and nickel oxides were working, the yield was comparatively small.So, in the second year of the present research, another nonelectrolysis gilding in palladium chloride.solution was tested. Tritium enrichment by anatase-palladium catalysis was investigated under ultraviolet light. The yield increased and the isotope separation factor was around 1.1. In order to apply the present method to industrial scale it is necessary to make contact well among solid (catalysis), liquid (water) and gas (vapor, hydrogen and oxygen). A trickle bed system was found to be optimum for maintaining the good contact. It was concluded that the trickle system should be investigated in the next study. Part of the results was presented in scientific journals and the rest will be presented in the near future. Less