Research on Phetoreduction System for Supercritical Carbon Dioxide

超临界二氧化碳光还原系统的研究

• 批准号: 13650912
• 负责人: HIROSE Takuji
• 金额: $ 2.37万
• 依托单位: Saitama University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13650912/
• 关键词: Ruthenium Polypyridine Complex; Cobalt Polypyridine Complex; Visible Light; Photoreduction of CO_2; Cation Exchange Polymer; Supercritical CO_2; Two phase system; 超臨界二酸化炭素; 光還元; 光触媒; ルテニウム錯体; コバルト錯体; 一酸化炭素; ターンオーバー数; CO; H_2選択性

In order to develop the molecular system, which can efficiently and practically reduce CO_2 to CO as a chemical resource using visible light, new ruthenium (Ru) and cobalt (Co) polypyridine complex-system was investigated from the following three points.1. Development of efficient metal complex catalystsIn order to develop efficient photo-induced electron transfer metal complex systems, Ru and Co complex units were connected by conjugated carbon chain and the new bimolecular complex was investigated. As a result, fast electron transfer was observed but back electron transfer was also accelerated and no improvement of CO_2 reduction efficiency was attained.2. Improvement of metal complex life time and development of solid catalytic systemCationic Ru and Co complexes were fixed to ion exchange polymer and its photo-induced CO_2 reduction ability was investigated. As a result, the followings were found : 1) Solid catalytic system is easy to handle and recover the metal complexes ; 2) Although the efficiency was not improved for each photoirradiation, the life time of the complex system became long and the total amount of CO produced was increased.3. Development of supercritical CO_2 reaction systemIn order to establish a reaction system under high pressure or supercritical CO_2, a reaction vessel was developed and reaction conditions were investigated for photo-reduction. As a result, high CO_2 reduction rate was obtained under organic solvent-supercritical CO_2 two phase system. Now the reproducibility is examined in detail and investigation of a new system under supercritical CO_2 phase is also on going.

为了开发一种能够在可见光下高效、实用地将CO_2还原为CO的分子体系，本论文从以下三个方面对钌（Ru）和钴（Co）多吡啶配合物体系进行了研究.高效金属配合物催化剂的开发为了开发高效的光诱导电子转移金属配合物体系，本文将Ru和Co配合物单元通过共轭碳链连接起来，研究了新型的双分子配合物。结果表明，电子转移速度较快，但电子反向转移速度加快，CO_2还原效率没有提高.金属配合物寿命的提高与固体催化体系的发展将阳离子Ru、Co配合物固定在离子交换聚合物上，考察了其光诱导CO_2还原能力。结果表明：1）固体催化体系易于处理和回收金属配合物; 2）虽然每次光照射的效率没有提高，但配合物体系的寿命变长，CO生成总量增加.超临界CO_2反应体系的研究为了建立超临界CO_2或高压下的反应体系，我们研制了一种光还原反应器，并对反应条件进行了研究。结果表明，在有机溶剂-超临界CO_2两相体系中，CO_2的还原率较高。目前，对超临界CO_2萃取体系的重现性进行了详细的考察，并对超临界CO_2萃取新体系进行了研究。

项目成果

広瀬卓司, 前野義人, 姫田雄一郎: "Photocatalytic carbon dioxide photoreduction by Co(bpy)_3^<2+> sensitized by Ru(bpy)_3^<2+> fixed to cation exchange polymer"Journal of Molecular Catalysis A : Chemistry. 193. 27-32 (2003)

Takuji Hirose、Yoshito Maeno、Yuichiro Himeda：“Co(bpy)_3^<2+> 敏化的 Co(bpy)_3^<2+> 光催化二氧化碳光还原固定在阳离子交换聚合物上”《分子催化杂志 A：化学》 . 193. 27-32 (2003)

Takuji Hirose, Yoshihito Maeno, Yuichiro Himeda: "Photocatalytic carbon dioxide photoreduction by Co(boy)_3^<2+> sensitized by Ru(bpy)_3^<2+> fixed to cation exchage polymer"Journel of Molecular Catalysis A : Chemistry. 193. 27-32 (2003)

Takuji Hirose、Yoshihito Maeno、Yuichiro Himeda：“Co(boy)_3^<2> 敏化的 Co(boy)_3^<2> 光催化二氧化碳光还原被 Ru(bpy)_3^<2> 固定到阳离子交换聚合物上”《分子催化杂志 A：化学》。