Characteristics and phytotoxicity assay of biochars derived from a Zn-rich antibiotic residue
Document Type
Article
Publication Date
5-1-2015
Abstract
Abstract The disposal and utilization of antibiotic residues (ARs) are a serious concern and have been identified as "a hazardous material" in China because of the residual antibiotic. However, little attention was paid to the potential environmental risk of the persistence of toxic heavy metals in those residues. Pyrolysis is an effective technology that used to reduce solid waste. Thus, in order to systematically investigate the influence of pyrolysis temperature and residence time on physicochemical characteristics, heavy metal speciation and bioavaibility in ARs derived biochars, ARs was pyrolyzed at different temperatures (300-700 °C) and residence time (1 and 2 h). The residue and biochar characteristics were characterized with a thermogravimetric analyzer, element analyzer, scanning electron microscopy, and Brunauer-Emmerr-Teller (BET) methods. Zn species in the biochars were determined with modified BCR sequential extraction procedure. The bioavailability of Zn in biochars and the resulted phytotoxicity were measured through a phytotoxicity test. Results indicated that both temperature and residence time have effects on biochar physiochemical properties, Zn speciation and bioavailability. Residual antibiotic was eliminated, and Zn was enriched and stabilized through pyrolysis. Zn bioavailability and phytotoxicity decreased with the increasing temperature and residence time. A temperature at 500 °C was optimal for this residue disposal. The results obtained in this study would enhance our knowledge on heavy metal transformation in pyrolysis and would be useful in designing an environment friendly approach to utilize this Zn-rich AR or other biowaste with similar characteristics.
Publication Source (Journal or Book title)
Journal of Analytical and Applied Pyrolysis
First Page
575
Last Page
583
Recommended Citation
Xiao, R., Sun, X., Wang, J., Feng, J., Li, R., Zhang, Z., Wang, J., & Amjad, A. (2015). Characteristics and phytotoxicity assay of biochars derived from a Zn-rich antibiotic residue. Journal of Analytical and Applied Pyrolysis, 113, 575-583. https://doi.org/10.1016/j.jaap.2015.04.006