Adsorptive Removal of Nitrate from Aqueous Solution Using Nitrogen Doped Activated Carbon

• Machida Motoi

  Safety and Health Organization, Chiba University Graduate School of Engineering, Chiba University

• Goto Tatsuru

  Graduate School of Engineering, Chiba University

• Amano Yoshimasa

  Safety and Health Organization, Chiba University Graduate School of Engineering, Chiba University

• Iida Tatsuya

  Graduate School of Engineering, Chiba University

抄録

Activated carbon (AC) has been widely applied for adsorptive removal of organic contaminants from aqueous phase, but not for ionic pollutants. In this study, nitrogen doped AC was prepared to increase the adsorption capacity of nitrate from water. AC was oxidized with (NH₄)₂S₂O₈ solution to maximize oxygen content for the first step, and then NH₃ gas treatment was carried out at 950°C to aim at forming quaternary nitrogen (N-Q) species on AC surface (Ox-9.5AG). Influence of solution pH was examined so as to elucidate the relationship between surface charge and adsorption amounts of nitrate. The results showed that Ox-9.5AG exhibited about twice higher adsorption capacity than non-treatment AC at any initial nitrate concentration and any equilibrium solution pH (pH_e) investigated. The more decrease in pH_e value, the more adsorption amount of negatively charged nitrate ion, because the surface charge of AC and Ox-9.5AG could become more positive in acidic solution. The oxidation and consecutive ammonia treatments lead to increase in nitrogen content from 0.35 to 6.4% and decrease in the pH of the point of zero charge (pH_pzc) from 7.1 to 4.0 implying that positively charged N-Q of a Lewis acid was created on the surface of Ox-9.5AG. Based on a Langmuir data analysis, maximum adsorption capacity attained 0.5–0.6 mmol/g of nitrate and adsorption affinity was 3.5–4.0 L/mmol at pH_e 2.5 for Ox-9.5AG.

収録刊行物

• ＣＨＥＭＩＣＡＬ　＆　ＰＨＡＲＭＡＣＥＵＴＩＣＡＬ　ＢＵＬＬＥＴＩＮ

  ＣＨＥＭＩＣＡＬ　＆　ＰＨＡＲＭＡＣＥＵＴＩＣＡＬ　ＢＵＬＬＥＴＩＮ 64 (11), 1555-1559, 2016

  公益社団法人 日本薬学会

キーワード

• nitrate
• adsorption
• activated carbon
• quaternary nitrogen
• oxidation
• ammonia

詳細情報

• CRID: 1390282679155281408
• NII論文ID: 130005268071
• NII書誌ID: AA00602100
• DOI: 10.1248/cpb.c16-00368
• ISSN: 13475223
• ISSN: 00092363
• NDL書誌ID: 027684510
• PubMed: 27803467
• Web Site: http://id.ndl.go.jp/bib/027684510
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I027684510
• Web Site: https://www.jstage.jst.go.jp/article/cpb/64/11/64_c16-00368/_pdf
• 本文言語コード: en
• データソース種別:
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  • NDL
  • Crossref
  • PubMed
  • CiNii Articles
  • KAKEN
• 抄録ライセンスフラグ: 使用不可