Ding Jiazheng, Liang Jiahao, Wang Qinghong, Tan Xiang, Xie Wenyu, Chen Chunmao, Li Changgang, Li Dehao, Li Jin, Chen Xiaoqing
Key Laboratory of Petrochemical Pollution Control of Guangdong Higher Education Institutes, Guangdong Engineering Technology Research Center of Petrochemical Pollution Control, School of Environmental Science and Engineering, Guangdong University of Petrochemical Technology, Maoming 525000, China.
State Key Laboratory of Heavy Oil Processing, State Key Laboratory of Petroleum Pollution Control, China University of Petroleum-Beijing, Beijing 102249, China.
Toxics. 2024 Sep 25;12(10):691. doi: 10.3390/toxics12100691.
Antibiotic pollution poses a serious environmental concern worldwide, posing risks to ecosystems and human well-being. Transforming waste activated sludge into adsorbents for antibiotic removal aligns with the concept of utilizing waste to treat waste. However, the adsorption efficiency of these adsorbents is currently limited. This study identified KOH modification as the most effective method for enhancing tetracycline (TC) adsorption by sludge biochar through a comparative analysis of acid, alkali, and oxidant modifications. The adsorption characteristics of TC upon unmodified sludge biochar (BC) as well as KOH-modified sludge biochar (BC-KOH) were investigated in terms of equilibrium, kinetics, and thermodynamics. BC-KOH exhibited higher porosity, greater specific surface area, and increased abundance of oxygen-based functional groups compared to BC. The TC adsorption on BC-KOH conformed the Elovich and Langmuir models, with a maximum adsorption capacity of 243.3 mg/g at 298 K. The adsorption mechanisms included ion exchange, hydrogen bonding, pore filling, and electrostatic adsorption, as well as π-π interactions. Interference with TC adsorption on BC-KOH was observed with HCO, PO, Ca, and Mg, whereas Cl, NO, and SO ions exhibited minimal impact on the adsorption process. Following three cycles of utilization, there was a slight 5.94% reduction in the equilibrium adsorption capacity, yet the adsorption capacity remained 4.5 times greater than that of unmodified sludge BC, underscoring its significant potential for practical applications. This research provided new insights to the production and application of sludge biochar for treating antibiotic-contaminated wastewater.
抗生素污染是全球范围内严重的环境问题，对生态系统和人类福祉构成风险。将废弃活性污泥转化为去除抗生素的吸附剂符合以废治废的理念。然而，目前这些吸附剂的吸附效率有限。本研究通过对酸、碱和氧化剂改性的比较分析，确定氢氧化钾改性是提高污泥生物炭对四环素（TC）吸附效果的最有效方法。从吸附平衡、动力学和热力学方面研究了未改性污泥生物炭（BC）和氢氧化钾改性污泥生物炭（BC-KOH）对TC的吸附特性。与BC相比，BC-KOH具有更高的孔隙率、更大的比表面积以及更多的含氧官能团。BC-KOH对TC的吸附符合Elovich和Langmuir模型，在298 K时最大吸附容量为243.3 mg/g。吸附机制包括离子交换、氢键、孔隙填充、静电吸附以及π-π相互作用。HCO、PO、Ca和Mg对BC-KOH吸附TC有干扰，而Cl、NO和SO离子对吸附过程影响极小。经过三个循环利用后，平衡吸附容量略有下降，降低了5.94%，但其吸附容量仍比未改性污泥生物炭BC高4.5倍，凸显了其在实际应用中的巨大潜力。该研究为污泥生物炭处理抗生素污染废水的生产和应用提供了新的见解。
