Formation Mechanism and Emission Control of Persistent Organohalogen Compounds at Low Temperatures

2019 Fiscal Year Final Research Report

• Project/Area Number: 17H01891
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Environmental engineering and reduction of environmental burden
• Research Institution: Hokkaido University
• Principal Investigator: TSUBOUCHI Naoto 北海道大学, 工学研究院, 准教授 (90333898)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 環境技術 / 環境対応 / 有害化学物質 / 表面・界面物性

Outline of Final Research Achievements

To understand the formation mechanism of organic chlorides by the reaction of HCl with carbonaceous particles, we used molecular orbital calculations for three carbon active site models (Armchair, Zigzag, and Tip types) to examine the effect of Zn doping on HCl adsorption. The molecular models of the carbon materials with or without Zn doping showed that the presence of Zn element increased the number of carbon active sites available for the chemical adsorption of HC. Furthermore, Zn doping changed the electronic state of the activesite of the carbon particle in the direction in which HCl was readily adsorbed. We also examined the HCl removal performance of cheap natural soda ash loaded on a honeycomb support as a hot gas cleanup method. The honeycomb-supported soda ash improved HCl removal extent at the 1-ppm breakthrough time compared to the result without the support. Under the present conditions, the removal extent was maximized at 500℃.

Free Research Field

環境化学

Academic Significance and Societal Importance of the Research Achievements

本研究では、分子軌道計算法を用いＺｎをドープした炭素のモデル構造の電子状態を調べ、Ｚｎにより電子が局在化する部分を特定する一方、ＨＣｌ吸着種の安定性を明らかにし、また、有機塩素種の塩素源の１つであるＨＣｌの除去を目的に、安価で資源量が豊富な天然ソーダ灰をハニカムに担持したＮａベース吸収剤を製造し、その高いＨＣｌ除去性能を見出した。本成果により、ＨＣｌによる未燃炭素粒子からの有機塩素化合物の発生を防止する手法の開発や有害化合物を発生させない添加剤などの開発が可能となり、学術的にも社会的にも意義の高い研究と言える。