Abstract
In this study, biochar was prepared via hybrid doping of N, O, and S by applying one-pot pyrolysis of poplar wood and S-containing urea formaldehyde at 900 °C. Different doping ratios were adopted, and the contents of O, N, and S were in the ranges of 2.78 – 5.56 %, 2.16 – 4.92 %, and 1.42 – 4.98 %, respectively. This hybrid doping significantly enhanced the efficiency of the removal of tetracycline (40 mg/L) from wastewater to 71.84 % in comparison with that attained by using normal poplar biochar (29.45 %). The adsorption kinetics and isotherms indicated that the adsorption process was favorable and was dominated by chemisorption instead of physisorption; the dominant adsorption process may be justified by the existence of abundant functional groups. The adsorption capacity was barely related to the surface area (R2 = 0.478), while it was closely related to the concentration of graphitic N (R2 = 0.985) because graphitic N enhanced the π–π interactions. The adsorption capacity was also highly related to the proportion of oxidized N and oxidized S owing to hydrogen bonding, which may have overlapped with the contribution of O-containing functional groups. This study presents a simple hybrid doping method for biochar modification and provides fundamental insights into the specific effects of O-, N- and S-containing functional groups on the performance of biochar for tetracycline removal.
Keywords
adsorption, biochar, functional groups, hybrid doping of N, O, and S, poplar, tetracycline
Document Type
Journal Article
Date of Publication
11-1-2022
Volume
15
Issue
21
Publication Title
Energies
Publisher
MDPI
School
School of Engineering
RAS ID
54077
Funders
Natural Science Foundation of Jiangsu Province (Grant No. BK20200794) / National Natural Science Foundation of China (Grant Nos. 52106249 and 51876093) / China MOST (Grant No. 2018YFE0183600) / Start-up Fund for Scientific Research of Nanjing Forestry University (Grant No. GXL2020002)
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Comments
Gao, W., Lin, Z., Yan, S., Gao, Y., Zhang, H., Hu, X., ... & Zhang, S. (2022). Preparation of N-, O-, and S-tri-doped biochar through one-pot pyrolysis of poplar and urea formaldehyde and its enhanced removal of tetracycline from wastewater. Energies, 15(21), 8081. https://doi.org/10.3390/en15218081