Comparison of the lead and copper adsorption capacities of plant source materials and their biochars. (15th April 2019)

• Record Type: Journal Article
• Authors: Lee, Myoung-Eun; Park, Jin Hee; Chung, Jae Woo
• Is Part Of: Journal of environmental management. Volume 236(2019)
• Page Start: 118
• Page End: 124
• Publication Date: 2019-04-15
• Subjects: Biochar -- Gingko leaf -- Peanut shell -- Metasequoia leaf -- Lead -- Copper; Environmental policy -- Periodicals; Environmental management -- Periodicals; Environment -- Periodicals; Ecology -- Periodicals; 363.705
• DOI: 10.1016/j.jenvman.2019.01.100
• Languages: English
• ISSNs: 0301-4797

Abstract

Abstract: Lead (Pb) and Cu are the most common pollutants found in industrial effluents which affect ecosystem and human health. To remove Pb and Cu from aquatic system, cost-effective and environmentally friendly adsorbents are required. Therefore, the study evaluated the adsorption of Pb and Cu by waste plant materials and their biochars. The adsorption kinetics and isotherms were applied to compare the Pb and Cu adsorption capacities using the gingko (Spiraea blumei) leaf (GL), peanut shell (PS), and Metasequoia leaf (ML), and their derived biochars (GB, PB, and MB, respectively). The GB showed a significantly higher Pb adsorption capacity than the other adsorbents. Maximum Pb adsorption by GB was 138.9 mg/g followed by GL (117.6 mg/g). The highest Cu adsorption (59.9 mg/g) was also achieved by GB followed by GL (57.8 mg/g). The carbonates and the phosphate functional groups in the GB and higher affinity of Pb to the functional groups contributed to higher Pb adsorption. The Pb adsorption kinetics on the plant source materials and their biochars followed a pseudo-second order model. The Pb and Cu adsorption capacities, with the exception of the GL, ML, and GB, are better explained by Langmuir-isotherm models. The carbonization did not always lead to better heavy metal adsorption. The Pb and Cu adsorption significantly reduced with carbonization of ML because of disappearance of oxygen containing functional groups. Therefore, appropriate method to prepare metal adsorbent should be selected depending on feedstocks and metal removal mechanisms. The GL is the most-abundant fallen leaf in the streets of the Republic of Korea; therefore, the use of the GL biochar for heavy-metal adsorption will also reduce the cost for waste disposal. Highlights: Ginkgo leaf biochar adsorbed 138.9 mg/g of Pb and 59.9 mg/g of Cu. Concentrated P of ginkgo leaf after carbonization contributed to the removal of Pb. Carbonization of Metasequoia leaf reduced Pb and Cu removal. Effect of carbonization was different depending on metal removal mechanisms.