有機鉱物の生成機構およびナノ鉱物の表面構造と反応性に関する研究

• 越後 拓也

  秋田大学大学院国際資源学研究科

書誌事項

タイトル別名

• The genesis of organic minerals and surface structures and reactivity of nanominerals
• 日本鉱物科学会研究奨励賞第22回受賞者 受賞記念研究紹介 有機鉱物の生成機構およびナノ鉱物の表面構造と反応性に関する研究
• ニホン コウブツ カガクカイ ケンキュウ ショウレイショウ ダイ22カイ ジュショウシャ ジュショウ キネン ケンキュウ ショウカイ ユウキ コウブツ ノ セイセイ キコウ オヨビ ナノ コウブツ ノ ヒョウメン コウゾウ ト ハンノウセイ ニ カンスル ケンキュウ

抄録

Organic minerals are natural organic compounds with both well-defined chemical composition and crystallographic properties; their occurrences show traces of the high concentration of certain organic compounds in natural environments. Thus the origin and formation process of organic minerals will lead us to understand the fate and behavior of the organic molecules in the lithosphere. All of each organic mineral can be classified into the one of following two groups: ionic organic minerals in which organic anions and various cations are held together by ionic bonds, and molecular organic minerals in which electroneutral organic molecules are bonded by weak intermolecular interactions. Karpatite, a natural crystal of coronene (C₂₄H₁₂), is the most typical molecular organic minerals and its crystal/molecular structures and carbon isotopic composition suggests that this mineral was crystallized from PAHs (polycyclic aromatic hydrocarbons)-rich hydrothermal petroleum by hydrothermal activity. In the process of formation of organic minerals, the formation of structural units, such as organic acid anion and PAH molecules, precedes their migration and concentration. The first stage includes the formation or cleavage of C-C bonds, but the latter stage does not. In addition, we have investigated the influence of size, morphology, surface structure, and aggregation state on the reductive dissolution of hematite with ascorbic acid using two types of nanoparticles with average diameters of 6.8 ± 0.8 nm and 30.5 ± 3.5 nm, referred to as Hem-7 and Hem-30, respectively, in this paper. TEM (transmission electron microscope) observation revealed that previous to dissolution, Hem-7 is present as both dispersed particles and as aggregates. Dispersed particles dissolve initially before aggregates, which influences its dissolution rate. The Hem-30 hematite has nanoscale surface steps and internal defects, and its dissolution initiates from the steps, defects, or sharp edges of the crystals. This study directly shows the importance of size, surface roughness, defects, crystal morphology and aggregation states on dissolution rates of nanoparticles.<br>

収録刊行物

• 岩石鉱物科学

  岩石鉱物科学 47 (1), 34-42, 2018

  一般社団法人　日本鉱物科学会

キーワード

• Organic minerals
• Polycyclic Aromatic Hydrocarbons
• Karpatite
• Crystal structure
• Carbon isotopic composition
• Hematite
• Ascorbic acid
• Grain size
• Crystal morphology
• Surface structure
• Aggregation state
• Dissolution rate

詳細情報

• CRID: 1390001206526061824
• NII論文ID: 130006516911
• NII書誌ID: AA1146088X
• DOI: 10.2465/gkk.180115
• ISSN: 13497979
• ISSN: 1345630X
• NDL書誌ID: 028928857
• Web Site: http://id.ndl.go.jp/bib/028928857
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I028928857
• Web Site: https://www.jstage.jst.go.jp/article/gkk/47/1/47_180115/_pdf
• 本文言語コード: ja
• データソース種別:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
  • KAKEN
• 抄録ライセンスフラグ: 使用不可