Tian Kun, Li Chunping, Liu Huiming, Wang Lianchun
Key Laboratory for Forest Resources Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Southwest Forestry University, Kunming, 650224, Yunnan, China.
College of Forestry, Southwest Forestry University, Kunming, 650224, Yunnan, China.
Sci Rep. 2025 Feb 28;15(1):7199. doi: 10.1038/s41598-025-91229-z.
To enhance the adsorption capacity of biochar (BC), herein a novel multifunction modified biochar (SDMBC) was prepared by directly crosslinking of the nanomicelle of sodium dodecyl sulfate/sapindus-saponin (SDS/SAP) composite system onto the BC through a simple, environmental friendly approach. Result showed that the adsorption performance of SDMBC has been greatly improved, compared with BC or using alone SDS and SAP, adsorption ability increased by 48.83%, 29.50%, 36.44%, respectively, the best modified effect was appeared when the concentration of SAP to SDS was 0.8 and 0.8 CMC. SDMBC exhibited high adsorption abilities of 130.23, 108.43, 277.09 125.27, 112.78 mg/g for heavy metal ions lead Pb(II), Cadmium Cd(II) and organic pollutants with different chemical properties bisphenol A(BPA), Methylene blue (MB), P-nitrophenol (PNP), respectively, higher than most previously reported adsorbents, importantly, SDMBC can still efficient removal capabilities even in the binary competition. Subsequently, the SDMBC and BC was characterized by Fourier Transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), Zeta potential (Zeta), it found SDMBC has a more layered structure, richer functional groups and more amorphous structure compared with BC, which are closely related with improving its adsorption capacity. The adsorption behavior of SDMBC for MB show that process was found to be spontaneous, propitious, endothermic, the adsorption isotherms fitted Freundlich models well, pseudo-second-order best describes kinetics adsorption, suggesting that the process is multi-layer chemical adsorption. The little affected by ionic strength and coexisting substances, could remained removal rate over a wide pH range, SDMBC still keep high removal rates even after 5 reuses. Based on FT-IR analysis, plausible adsorption mechanism proposed, including hydrogen bond, electrostatic attraction and π-π bonding. Cost analysis manifests that the SDMBC are high efficiency and cheap eco-adsorbents compared with commercial activated carbon, and the SDMBC dosage required for the removal of 99% of a fixed amount of MB in different volumes of effluent was predicted. Seven machine learning (ML) models were used to predict the MB (60 mg/L) adsorption of the SDMBC, using Shapley Additive Explanations (SHAP) for model interpretation. Finding Extreme Gradient Boosting (XGBoost) exhibited best performance, the order of feature importance as time> Ratio> pH> concentration> temperature. Thus, SDMBC as a new cheap and eco-adsorbents, can be used to effectively remove various types of pollutants, has a great application potential in sewage treatment, while the accurate ML prediction model presented a valuable advice for designing efficient adsorbents and optimization operating conditions in the future.
为提高生物炭（BC）的吸附能力，本文通过一种简单、环保的方法，将十二烷基硫酸钠/无患子皂苷（SDS/SAP）复合体系的纳米胶束直接交联到BC上，制备了一种新型多功能改性生物炭（SDMBC）。结果表明，与BC或单独使用SDS和SAP相比，SDMBC的吸附性能有了很大提高，吸附能力分别提高了48.83%、29.50%、36.44%，当SAP与SDS的浓度为0.8和0.8 CMC时，改性效果最佳。SDMBC对重金属离子铅Pb(II)、镉Cd(II)以及具有不同化学性质的有机污染物双酚A(BPA)、亚甲基蓝(MB)、对硝基苯酚(PNP)的吸附能力分别为130.23、108.43、277.09、125.27、112.78 mg/g，高于大多数先前报道的吸附剂，重要的是，即使在二元竞争中，SDMBC仍具有高效的去除能力。随后，通过傅里叶变换红外光谱（FT-IR）、X射线衍射（XRD）、扫描电子显微镜（SEM）、Zeta电位（Zeta）对SDMBC和BC进行了表征，发现与BC相比，SDMBC具有更层状的结构、更丰富的官能团和更多的无定形结构，这与提高其吸附能力密切相关。SDMBC对MB的吸附行为表明，该过程是自发、有利、吸热的，吸附等温线很好地拟合了Freundlich模型，伪二级动力学最能描述吸附过程，表明该过程是多层化学吸附。该过程受离子强度和共存物质的影响较小，在较宽的pH范围内仍能保持去除率，SDMBC即使经过5次重复使用仍能保持较高的去除率。基于FT-IR分析，提出了合理的吸附机理，包括氢键、静电吸引和π-π键合。成本分析表明，与商业活性炭相比，SDMBC是高效且廉价的生态吸附剂，并预测了在不同体积的废水中去除99%固定量MB所需的SDMBC用量。使用七种机器学习（ML）模型预测SDMBC对MB（60 mg/L）的吸附，并使用Shapley Additive Explanations（SHAP）进行模型解释。结果发现极端梯度提升（XGBoost）表现最佳，特征重要性顺序为时间>比例>pH>浓度>温度。因此，SDMBC作为一种新型廉价的生态吸附剂，可有效去除各类污染物，在污水处理中具有巨大的应用潜力，而精确的ML预测模型为未来设计高效吸附剂及优化操作条件提供了有价值的建议。
