The speciation of copper and zinc in the incineration fly ash of a municipal solid waste in Taiwan was investigated in the present work. By the least-squares fitted X-ray absorption near edge structural (XANES) spectroscopy, we found that CuCO3, Cu(OH)2, and CuO (fractions of 0.09, 0.39 and 0.51, respectively) were the main copper species in the fly ash. Quantitative analysis of the extended X-ray absorption fine structural (EXAFS) spectra indicated that the bond distance of Cu-O in the fly ash was 1.96Å with a coordination number (CN) of 3.9 in the first shell of copper. In the second shell, the bond distance and CN of Cu-(O)-Cu were 2.91Å and 2.7, respectively. In addition, speciation of Zn was also examined in the same X-ray absorption energy (8780-9970eV). The bond distance of Zn-O and Zn-O-Zn were 1.97 and 2.94Å, respectively. However, the Zn-O-Cu structure was not found because of the physically unreasonable σ2 (Debye-Waller factor) values in the EXAFS data fitting process.
All Science Journal Classification (ASJC) codes
- Environmental Engineering
- Environmental Chemistry
- Waste Management and Disposal
- Health, Toxicology and Mutagenesis