Common Mechanisms: Thermochemical Formation of Organohalogen Compounds in Environmental Heterogeneous Solid Phase

2019 Fiscal Year Final Research Report

• Project/Area Number: 17H04718
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Single-year Grants
• Research Field: Environmental risk control and evaluation
• Research Institution: Kyoto University
• Principal Investigator: Fujimori Takashi 京都大学, 工学研究科, 助教 (20583248)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 有機塩素化合物 / 有機臭素化合物 / 共通機構 / 焼却 / 野焼き / 化学形態 / その場観察

Outline of Final Research Achievements

In the present study, objective is to propose the “common mechanisms” of thermochemical formation of the organohalogen compounds (OCs) in environmental heterogeneous solid phase. Hypotheses of this study were (i) common mechanisms to promote OCs by metals and (ii) halogenation of carbon: Commonality between chlorine and bromine. Systematical model studies focusing on metallic copper revealed common halogenation mechanisms of carbon in between chlorine and bromine. To compare with results derived from model studies, real samples were collected from an open burning site of municipal solid waste (Zambia) and an electronic-waste open burning site (Ghana). Then we tested hypotheses by using dataset measured by real samples. Quantitative assessment of total amount of organic halogen was developed as advanced theme.

Free Research Field

環境化学、廃棄物工学、分析化学

Academic Significance and Societal Importance of the Research Achievements

本研究では、様々な熱プロセスを分断して考えるのではなく、互いに共通して潜んでいる支配機構（共通機構）を通じた現象理解を試みた。その結果、特定の条件が揃った場合に、塩素・臭素のハロゲン種に依らない有機ハロゲン化合物生成に関わる共通機構が明らかになった。熱プロセスは「都市ごみ焼却」、汚染質は「塩素化ダイオキシン類」という典型的な研究図式を超え、より一般的な条件に基づいた「熱プロセスからの有機ハロゲン化合物の生成機構」に関する本質的な反応理解に基づいた適切な汚染質制御・管理に繋がることが予想される。