Ma Feng-Feng, Zheng Xu-Dong, Zhao Hao, Kang Hong-Bing, Li Qing, Jiao Ya-Xian, Zhang Jian
School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China.
Huan Jing Ke Xue. 2025 Jul 8;46(7):4349-4359. doi: 10.13227/j.hjkx.202406156.
Corn stalks were prepared into biochar （CSBC）， and modified biochar （MCSBC） was obtained by treatment with NaOH. The adsorption characteristics of phenol and ammonium nitrogen （NH-N） on CSBC and MCSBC were studied using a batch equilibrium method. The effects of dosage and solution pH on the adsorption of phenol and NH-N by MCSBC were investigated， and the adsorption mechanisms were explored based on the experimental results and characterization data. The results showed that the adsorption of phenol on CSBC and MCSBC was a diffusion process involving heterogeneous and multiple reaction synergistic effects. The adsorption of NH-N was mainly governed by chemical adsorption， and the adsorption processes of phenol and NH-N on CSBC and MCSBC were primarily monolayer adsorption. Isothermal adsorption data indicated that in the binary component system， the maximum adsorption capacities （） of MCSBC for phenol and NH-N were 415.81 mg·g and 287.73 mg·g， respectively， which increased by 361.55% and 11.67% compared with those in the single-component system. The adsorption of phenol by MCSBC was more effective under acidic conditions， while the adsorption of NH-N was more effective under alkaline conditions. When both components coexisted， the average pH value of 8 from coking wastewater could be adopted. The optimal dosage was 4 g·L， and MCSBC demonstrated good recycling and regeneration capabilities. The adsorption mechanisms of phenol by MCSBC included π-π interactions， hydrogen bonding， and pore-filling effects. The adsorption mechanisms of NH-N included pore filling， hydrogen bonding， ion exchange， and electrostatic attraction. In the binary component system， the preferential adsorption of NH-N could significantly enhance the adsorption of phenol on MCSBC through charge-assisted hydrogen bonding. In summary， MCSBC shows high potential for treating phenol and NH-N in coking wastewater.
将玉米秸秆制备成生物炭（CSBC），通过NaOH处理得到改性生物炭（MCSBC）。采用批量平衡法研究了CSBC和MCSBC对苯酚和氨氮（NH-N）的吸附特性。考察了投加量和溶液pH对MCSBC吸附苯酚和NH-N的影响，并根据实验结果和表征数据探讨了吸附机理。结果表明，CSBC和MCSBC对苯酚的吸附是一个涉及非均相和多反应协同效应的扩散过程。NH-N的吸附主要受化学吸附控制，CSBC和MCSBC对苯酚和NH-N的吸附过程主要为单层吸附。等温吸附数据表明，在二元体系中，MCSBC对苯酚和NH-N的最大吸附量（）分别为415.81 mg·g和287.73 mg·g，与单组分体系相比分别提高了361.55%和11.67%。MCSBC在酸性条件下对苯酚的吸附效果更好，而在碱性条件下对NH-N的吸附效果更好。当两种组分共存时，可采用焦化废水的平均pH值8。最佳投加量为4 g·L，MCSBC表现出良好的循环利用和再生能力。MCSBC对苯酚的吸附机理包括π-π相互作用、氢键和孔填充效应。NH-N的吸附机理包括孔填充、氢键、离子交换和静电吸引。在二元体系中，NH-N的优先吸附可通过电荷辅助氢键显著增强MCSBC对苯酚的吸附。综上所述，MCSBC在处理焦化废水中的苯酚和NH-N方面具有很大潜力。
