Removal of selected metal ions from aqueous solution using modified corncobs
T Vaughan1, C W Seo, W E Marshall
1Department of Human Environment and Family Sciences, North Carolina A&T State University, Greensboro 27411, USA.
Bioresource Technology
|May 3, 2001
Summary
Chemically modified corncobs effectively remove metal ions from wastewater, matching commercial adsorbents for certain metals. This agricultural waste offers a sustainable solution for water purification.
Area of Science:
- Environmental Science
- Materials Science
- Chemical Engineering
Background:
- Wastewater treatment requires efficient metal ion adsorbents.
- Agricultural waste like corncobs presents an underutilized resource.
- Developing cost-effective and sustainable adsorbents is crucial.
Purpose of the Study:
- To convert corncobs into effective metal ion adsorbents for wastewater treatment.
- To evaluate the adsorption efficiency of chemically modified corncobs for various metal ions.
- To compare the performance of modified corncobs against commercial adsorbent resins.
Main Methods:
- Corncobs were ground and chemically modified using citric acid or phosphoric acid.
- Adsorption efficiency was tested for individual and mixed metal ion solutions (Cd, Cu, Pb, Ni, Zn).
- Performance was benchmarked against commercial resins: Amberlite IRC-718, Amberlite 200, Duolite GT-73, and CMC.
Main Results:
- Modified corncobs demonstrated comparable adsorption to Duolite GT-73 for Cd, Cu, Ni, and Zn.
- Adsorption of Ni and Zn by modified corncobs exceeded that of CMC.
- For mixed metals, modified corncobs matched Duolite GT-73 for Cd and Cu, and Amberlite IRC-718 for Pb.
- Commercial resins generally showed higher capacities, but modified corncobs were equivalent to Duolite GT-73 for Cu and Pb.
Conclusions:
- Chemically modified corncobs exhibit significant potential as metal ion adsorbents in wastewater treatment.
- Their performance is comparable to commercial cation exchange resins for specific metal ions and conditions.
- Utilizing corncobs offers a sustainable and potentially economical alternative for water remediation.
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