Development of water treatment technology with selectivity using sulfate radicals

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K04667
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 22060:Environmental systems for civil engineering-related
• Research Institution: Tokyo Metropolitan University
• Principal Investigator: Sakai Hiroshi 東京都立大学, 都市環境科学研究科, 准教授 (70533123)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 硫酸ラジカル

Outline of Final Research Achievements

In this study, we attempted to determine the effect of sulfate radical treatment on persistent organic matter by UV irradiation in the form of either persulfate or hydrogen peroxide. Compared to hydrogen peroxide, persulfate showed a higher reduction rate and efficiency at the same UV dose. The results of experiments with humic acid, amino acids, and various dyes showed differences in UV254 absorbance and NPOC reduction trends, with the absorbance reduction rate being greater than that of NPOC at the initial stage.
As a mechanism, it is thought that the difference in bond dissociation energy of persulfate compared to hydrogen peroxide causes a higher concentration of radicals and a higher decomposition rate.

Free Research Field

紫外線水処理

Academic Significance and Societal Importance of the Research Achievements

難分解性の有機物は、地表水や地下水でよく見られる有機化合物の複雑なマトリックスであり、飲料水処理に大きな影響を与える。その中でも疎水性NOMはNOMの主要な構成要素と考えられており、水中のDOCの半分を占めている。
本研究では、フミン酸を用い、過硫酸塩または過酸化水素を添加した形で紫外線照射を行うことで、難分解性有機物に対する硫酸ラジカル処理の効果を明らかにすることを試み、過酸化水素に代わる新たな処理として、硫酸ラジカル処理の効果を明らかにした。