Quaternary-nitrogen functionalized carbonaceous adsorbent derived from coffee grounds for nitrate removal from
Li-Han Luo1, Yoshimasa Amano2,3, Motoi Machida2,3
1Graduate School of Science and Engineering, Chiba University, Chiba, Japan.
Summary
Nitrate contamination is a growing problem. Researchers developed a novel nitrogen-doped carbon material from coffee grounds that effectively removes nitrate from water, even under varying pH conditions, showing promise for water treatment applications.
Area of Science:
- Environmental Science
- Materials Science
- Chemistry
Background:
- Nitrate contamination from agriculture and industrialization is a significant global environmental concern.
- Effective and sustainable methods for nitrate removal from water are urgently needed.
Purpose of the Study:
- To synthesize and characterize a novel nitrogen-doped porous carbon material for nitrate adsorption.
- To evaluate the nitrate adsorption capacity and stability of the developed material.
Main Methods:
- Synthesis of nitrogen-doped porous carbon (Cf-U1Z1-450) from coffee grounds using urea-assisted doping.
- Structural characterization to confirm the incorporation of quaternary nitrogen (N-Q) species.
- Batch and fixed-bed column adsorption experiments to assess nitrate removal efficiency and material stability.
Main Results:
- The synthesized Cf-U1Z1-450 material effectively incorporated N-Q groups, enhancing adsorption performance.
- Maximum nitrate adsorption capacity of 0.62 mmol/g was achieved at pH 3, with significant uptake observed across a wide pH range (3-11).
- The material demonstrated excellent regeneration ability and stability, maintaining adsorption capacity over five cycles in fixed-bed experiments.
Conclusions:
- Quaternary nitrogen functional groups play a critical role in enhancing nitrate removal.
- Biomass-derived carbon materials modified with N-Q groups show significant potential for practical application in treating nitrate-contaminated water.
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