Mn3O4/g-C3N4催化臭氧降解聚乳酸微塑料研究
Study on the Degradation of Polylactic Acid Microplastics by Mn3O4‑C3N4 Catalytic Ozonation
摘要: 为探究可生物降解聚乳酸微塑料(PLA-MPs)的高效去除方法，本研究通过构建石墨相氮化碳复合四氧化三锰(Mn3O4/g-C3N4)催化臭氧(O3)体系，对比分析了其与单独O3对PLA-MPs的降解效能及表面性质影响。样品经不同氧化时间(1、3、5、8 h)处理后，利用扫描电子显微镜、傅里叶变换红外光谱、Zeta电位、接触角、溶解性有机碳及三维荧光光谱等手段进行系统表征。结果表明，Mn3O4-C3N4显著提升O3降解效率，氧化8 h后PLA-MPs失重率达18.685% (单独O3为13.075%)；催化氧化导致PLA-MPs表面形貌严重破损、羰基指数升高至15.253、亲水性增强(接触角从72.1˚降至45.8˚)且表面电荷负向移动(Zeta电位由−25.523 mV降至−38.833 mV)。浸出液分析显示，该体系不仅生成更多可溶性有机物(DOC浓度最高达24.847 mg/L)，同时促进了浸出有机物的进一步氧化转化。研究证明Mn3O4/g-C3N4催化O3体系通过催化产生羟基自由基，有效断裂PLA分子链并改变其表面性质，为评估可生物降解微塑料在高级氧化工艺中的环境行为提供了实验依据。
Abstract: To investigate effective removal methods for biodegradable polylactic acid microplastics (PLA-MPs), this study constructed a graphitic carbon nitride composited manganese tetraoxide (Mn3O4/g-C3N4) catalytic ozonation system and compared its degradation performance and surface property changes with ozone (O3) alone. The samples were systematically characterized after being treated with different oxidation times (1, 3, 5, and 8 hours) using scanning electron microscopy, Fourier transform infrared spectroscopy, zeta potential measurement, contact angle analysis, dissolved organic carbon determination, and three-dimensional fluorescence spectroscopy. The results showed that Mn3O4-C3N4 significantly enhanced the degradation efficiency of O3, with a weight loss of PLA-MPs reaching 18.685% after 8 h (compared to 13.075% for O3 alone). Catalytic oxidation caused severe surface damage, increased the carbonyl index to 15.253, improved hydrophilicity (contact angle decreased from 72.1˚ to 45.8˚), and shifted the surface charge negatively (Zeta potential changed from −25.523 mV to −38.833 mV). Leachate analysis reveals that this system not only produces a greater quantity of soluble organic matter (with a maximum DOC concentration of 24.847 mg/L), but also promotes the further oxidative transformation of the leached organics. The study demonstrates that the Mn3O4/g-C3N4/O3 system effectively cleaves PLA molecular chains and alters its surface properties through hydroxyl radicals produced by catalytic ozonation, providing experimental evidence for evaluating the environmental behavior of biodegradable microplastics in advanced oxidation processes.
文章引用：李浩宇, 葛建华, 杨心茹, 程晶晶, 李渊博, 回志扬, 王静. Mn3O4/g-C3N4催化臭氧降解聚乳酸微塑料研究[J]. 环境保护前沿, 2026, 16(8): 1431-1443. https://doi.org/10.12677/aep.2026.168144

参考文献

[1] Lamberti, F.M., Román-Ramírez, L.A. and Wood, J. (2020) Recycling of Bioplastics: Routes and Benefits. Journal of Polymers and the Environment, 28, 2551-2571.
https://doi.org/10.1007/s10924-020-01795-8
[2] 冯琴霜, 张丽雪, 唐炳然, 等. 聚乳酸塑料在淡水沉积物中的降解过程[J]. 中国环境科学, 2024, 44(11): 6228-6240.
[3] Fan, P., Yu, H., Xi, B. and Tan, W. (2022) A Review on the Occurrence and Influence of Biodegradable Microplastics in Soil Ecosystems: Are Biodegradable Plastics Substitute or Threat? Environment International, 163, Article 107244.
https://doi.org/10.1016/j.envint.2022.107244
[4] Wi, J., Choi, J. and Lee, S.H. (2025) PLA-Based Biodegradable Polymer from Synthesis to the Application. Polymers, 18, 121.
https://doi.org/10.3390/polym18010121
[5] Ma, L., Fan, Z.Y., Lian, W.Q., Wei, X.F., Bao, R.Y. and Yang, W. (2025) Nanoplastics and Microplastics Released from an Enzyme-Embedded Biodegradable Polyester during Hydrolysis. Journal of Hazardous Materials, 489, Article 137640.
https://doi.org/10.1016/j.jhazmat.2025.137640
[6] Payanthoth, N.S., Kim, C., Ralte, L., Mut, N.N.N., Tiwari, D. and Jung, J. (2026) Aerobic Microbial Degradation of PLA, PHB, and PBAT Microplastics in Freshwater: Different Structural Changes and Byproduct Formation. Journal of Environmental Chemical Engineering, 14, Article 121387.
https://doi.org/10.1016/j.jece.2026.121387
[7] 李梦梦. 环巢湖污水处理厂微塑料赋存特征及去除规律研究[D]: [硕士学位论文]. 合肥: 合肥大学, 2025.
[8] 刘文佳, 邢琳琼, 杨梦鑫, 等. 非均相金属催化剂催化臭氧氧化难降解有机废水研究进展[J]. 应用化工, 2025, 54(11): 2952-2957.
[9] Faria, P.C.C., Monteiro, D.C.M., Órfão, J.J.M. and Pereira, M.F.R. (2009) Cerium, Manganese and Cobalt Oxides as Catalysts for the Ozonation of Selected Organic Compounds. Chemosphere, 74, 818-824.
https://doi.org/10.1016/j.chemosphere.2008.10.016
[10] 李旭芳, 沈鹏飞, 马鲁铭. 污水深度处理中常见固相臭氧催化剂及其催化机理综述[J]. 净水技术, 2024, 43(3): 16-28.
[11] Rocha, G.F.S.R., da Silva, M.A.R., Rogolino, A., Diab, G.A.A., Noleto, L.F.G., Antonietti, M., et al. (2023) Carbon Nitride Based Materials: More than Just a Support for Single-Atom Catalysis. Chemical Society Reviews, 52, 4878-4932.
https://doi.org/10.1039/d2cs00806h
[12] 陈怡, 何银宁, 汪达, 等. 碳氮掺杂Mn3O4催化臭氧氧化降解水中2, 3-二甲基吡嗪[J]. 中国环境科学, 2025, 45(3): 1251-1259.
[13] Duan, L., Wang, Z., Hou, Y., Wang, Z., Gao, G., Chen, W., et al. (2016) The Oxidation Capacity of Mn3O4 Nanoparticles Is Significantly Enhanced by Anchoring Them onto Reduced Graphene Oxide to Facilitate Regeneration of Surface-Associated Mn(III). Water Research, 103, 101-108.
https://doi.org/10.1016/j.watres.2016.07.023
[14] 葛建华, 刘丹, 张万, 等. O3促进聚乙烯(PE)和聚苯乙烯(PS)与联苯胺的相互作用[J]. 环境化学, 2025, 44(4): 1424-1436.
[15] 何子阳, 宋小宇, 邹海明. 磁性Fe3O4/Mg-藻渣生物炭复合材料活化过硫酸盐处理甲基橙染料废水的应用[J]. 安徽科技学院学报, 2024, 38(4): 38-43.
[16] Wu, X., Zhang, H., Chen, J., Tan, F., Cai, R. and Wang, Y. (2025) Photoaging Promotes Toxic Micro/Nanoplastics Release from PLA/PBAT Biodegradable Plastic in Gastrointestinal Condition. Environment & Health, 3, 446-457.
https://doi.org/10.1021/envhealth.4c00209
[17] Easton, T., Koutsos, V. and Chatzisymeon, E. (2023) Removal of Polyester Fibre Microplastics from Wastewater Using a UV/H2O2 Oxidation Process. Journal of Environmental Chemical Engineering, 11, Article 109057.
https://doi.org/10.1016/j.jece.2022.109057
[18] 张妮妮, 李亮, 包睿敏, 等. 掺杂银纳米粒子的钴基金属-有机框架纳米复合材料对土霉素的光催化降解[J]. 安徽科技学院学报, 2024, 38(5): 92-98.
[19] Zhou, W., Chen, S., Liu, Y., Liang, F., Lü, M., Liang, X., et al. (2025) Study on the Effect of Acid-Aged PS and PLA on the Adsorption Characteristics of Cd2+, Cu2+ and Zn2+. Journal of Environmental Chemical Engineering, 13, Article 120355.
https://doi.org/10.1016/j.jece.2025.120355
[20] Romera-Castillo, C., Pinto, M., Langer, T.M., Álvarez-Salgado, X.A. and Herndl, G.J. (2018) Dissolved Organic Carbon Leaching from Plastics Stimulates Microbial Activity in the Ocean. Nature Communications, 9, Article No. 1430.
https://doi.org/10.1038/s41467-018-03798-5
[21] Wang, X., Chen, J., Jia, W., Huang, K. and Ma, Y. (2024) Comparing the Aging Processes of PLA and PE: The Impact of UV Irradiation and Water. Processes, 12, Article 635.
https://doi.org/10.3390/pr12040635
[22] 王华印. PET纤维紫外光降解研究[J]. 广西轻工业, 2009, 25(8): 23-24, 28.
[23] 王小娟. 水中微塑料的光老化对其浸出物及吸附抗生素性能的影响研究[D]: [硕士学位论文]. 山西: 中北大学, 2023.
[24] Lee, Y.K., Murphy, K.R. and Hur, J. (2020) Fluorescence Signatures of Dissolved Organic Matter Leached from Microplastics: Polymers and Additives. Environmental Science & Technology, 54, 11905-11914.
https://doi.org/10.1021/acs.est.0c00942
[25] 谢彬, 白茸茸, 孙华山, 等. 聚乳酸塑料合成、生物降解及其废弃物处置的研究进展[J]. 生物工程学报, 2023, 39(5): 1912-1929.
[26] 常潇, 刘倩, 孙梦瑶, 等. 微/纳米塑料的降解机制与微生物治理研究进展[J]. 应用生态学报, 2025, 26(11): 3535-3548.
[27] Dutta, M., Kumar, S., Bhimireddi, R., Shukla, M., Koparkar, A.R., Sharma, K.P., et al. (2026) Advanced Photocatalytic Materials for Micro/Nanoplastic Degradation: A Comprehensive Review. Environmental Surfaces and Interfaces, 4, 152-189.
https://doi.org/10.1016/j.esi.2026.02.001