Decomposition Characteristics of Organics Dissolved in Water under Irradiation of Diffuse Light Including Far UV Light and Excimer Light

远紫外光和准分子光漫射光照射下溶解于水中的有机物的分解特性

• 批准号: 07455311
• 负责人: SUGAWARA Takuo
• 金额: $ 4.42万
• 依托单位: Akita University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07455311/
• 关键词: far UV light; excimer light; UV oxidation; total organic carbon; photoreactor; annular flow photoreactor; ultrapure water; low-pressure mercury lamp; 全有機体炭素; 内部フィルター効果; 資源循環; 紫外線; エキレマ-光

In line with the research on process developments of recycle use of ultrapure water for cleaning semiconductor elements, we firstly examined the possibilities of a process which could decompose a trace amount of organics dissolved in oxygen-free water by irradiating far UV (ultaviolet) 185nm light, and UV 354nm light with a low-pressure mercury lamp. We secondly tried evaluating the effect of far UV light by comparing the above-mentioned results to the one with far UV 172nm excimer light irradiation. Complete decomposition of TOC has been achieved even in the absence of oxygen with methanol as an initial reactant. Direct decomposition of organics is dominant here in comparison with the case of irradiation in the presence of oxygen where a hydroxyl radical plays an important role.We thirdly aimed at modelling kinetics of far UV degradation of TOC in the presence of oxygen, a far (vacuum) UV oxidation process, because a quantitative interpretation of decomposition characteristics in the presence of oxygen is also important from a practical point of view. As described in the present report, precise data have been accumulated with good use of a TOC analyzer and an excimer lamp respectively purchased under the grant-in-aid ; especially the sole effect of far UV light was clearly evaluated with the excimer lamp. Simulation of the decomposition hehavior observed is now being conducted with reaction-rate equations based on the stoichiometric equations governing methanol, formaldehyde, and formic acid decomposition to form hydrogen peroxide. Results will soon be reported.

结合半导体元件清洗用超纯水循环利用工艺开发的研究，首先考察了用低压汞灯照射远紫外（ultaviolet）185 nm光和紫外354 nm光，可以分解溶解在无氧水中的微量有机物的工艺的可能性。我们第二次尝试通过比较上述结果与远紫外172 nm准分子光照射的结果来评估远紫外光的效果。即使在没有氧气的情况下，用甲醇作为初始反应物，也实现了TOC的完全分解。直接分解的有机物是占主导地位的，在这里与照射的情况下，在氧的存在下，羟基自由基起着重要的作用。我们第三次的目的是在建模动力学的TOC在氧的存在下，远（真空）紫外线氧化过程中，远紫外线降解，因为在氧的存在下的分解特性的定量解释也是重要的，从实用的角度来看。如本报告所述，通过充分利用分别在补助金下购买的TOC分析仪和准分子灯，积累了精确的数据;特别是利用准分子灯明确评估了远紫外光的唯一影响。现在正在进行模拟的分解异构体或观察到的反应速率方程的基础上的化学计量方程甲醇，甲醛和甲酸分解形成过氧化氢。结果将很快报告。