改性壳聚糖 /纳米 TiO ₂微球的制备及其对磷酸盐的吸附研究

Preparation of Modified Chitosan/Nano-Tio ₂ Microspheres and Their Adsorption of Phosphate

摘要

过量的磷酸盐会导致水体富营养化。本文以壳聚糖为原料，在壳聚糖氨基上引入季铵阳离子，并负载纳米TiO ₂，通过凝胶包埋法制备壳聚糖季铵盐/纳米二氧化钛复合微球MTHAC，研究其对水中磷酸盐的吸附性能。对微球进行FTIR、XRD、Zeta等表征分析，通过响应面法优化吸附条件以及对吸附动力学和吸附等温线模型进行拟合，研究MTHAC对磷酸盐的吸附性能。结果表明，MTHAC表面呈颗粒状，TiO ₂均匀分布在表面，颗粒间富含氨基活性位点。MTHAC 在pH 为2-8 间保持正电性。响应面法优化的最佳吸附条件为pH3、磷酸盐初始浓度50.0 mg·L ⁻¹、吸附时间20 h，复合微球对磷酸盐的吸附量为48.7 mg·g ⁻¹，去除率为97.3%。吸附过程符合准二级动力学模型和Langmuir等温模型，揭示了吸附为以配体交换和静电作用为主的单层吸附。MTHAC对磷酸盐具有良好的可循环吸附性能，并对大肠杆菌与金黄色葡萄球菌表现出显著的抑菌作用，有望作为一种兼具抑菌与吸附双功能的除磷材料应用于污水处理领域。

Abstract

Excessive phosphate can lead to eutrophication of water bodies. In this study, chitosan is used as the raw material to introduce quaternary ammonium cations onto the amino groups of chitosan, and nano-TiO ₂ is loaded to prepare Microsphere Titanium dioxide Hydroxypropyltrimethylammonium Chloride Chitosan (MTHAC) via a gel-embedding method. The adsorption performance of MTHAC for phosphate in water is investigated. The microspheres are characterized by FTIR, XRD, and Zeta. The adsorption conditions are optimized using response surface methodology, and the adsorption kinetics and isotherm models are fitted to study the adsorption mechanism. The results indicate that the MTHAC surface exhibits a granular structure, with TiO₂ uniformly distributed across it, and abundant amino active sites between particles. The MTHAC maintains a positive surface charge within a pH range of 2 – 8. Under optimized conditions (pH 3, initial phosphate concentration of 50.0 mg·L ⁻¹, and adsorption time of 20 h), the maximum adsorption capacity of the composite microspheres reaches 48.7 mg·g ⁻¹ with a removal efficiency of 97.3%. The adsorption process follows the pseudo-second-order kinetic model and the Langmuir isotherm model, revealing a monolayer adsorption mechanism dominated by ligand exchange and electrostatic interactions. MTHAC shows favorable recyclable adsorption capacity for phosphate and exhibits significant bacteriostatic activity against Escherichia coli and Staphylococcus aureus. It holds promising potential as a dual-functional phosphorus-removing material integrating bacteriostatic and adsorption properties for application in wastewater treatment.

关键词

壳聚糖 / 二氧化钛 / 吸附 / 磷酸盐

Key words

Chitosan / titanium dioxide / adsorption / phosphate

参考文献

[1] Wang Y, Chen L, Zhu Y, et al. Research status, trends, and mechanisms of biochar adsorption for wastewater treatment: a scientometric review[J]. Environmental Sciences Europe, 2024, 36: 1-25.

[2] Zong E, Zhang C, Wu S, et al. Titanium dioxide nanoparticles functionalized chitosan toward bio-based antibacterial adsorbent for enhanced phosphate capture[J]. International Journal of Biological Macromolecules, 2023, 241: 124511.

[3] Zhang X, Sun S, Han X, et al. Phosphorus recovery from urban wastewater treatment in China: Current status, future potential and a roadmap for sustainable development[J]. Journal of Water Process Engineering, 2025, 69: 106806.

[4] Carrilo V, Castillo R, Magri A, et al. Phosphorus recovery from domestic wastewater: A review of the institutional framework[J]. Journal of Environmental Management, 2024, 351: 119812.

[5] Costigan E M, Oehler M A, Macrae J D . Phosphorus recovery from recirculating aquaculture systems: Adsorption kinetics and mechanism[J]. Journal of Water Process Engineering, 2022, 49: 102992.

[6] Cheng F, Zhang Z, Zhao C, et al. Interception of internal phosphorus release from sediments by lanthanum-modified shrimp shell biochar in two application modes[J]. Journal of Cleaner Production, 2024, 471: 143450.

[7] Mi F L, Chen W Y, Chen Z R, et al. Sequential removal of phosphate and copper (II) ions using sustainable chitosan biosorbent[J]. International Journal of Biological Macromolecules, 2024, 266: 131178.

[8] Eltaweil A S, Omer A M, Ei-aqapa H G, et al. Chitosan based adsorbents for the removal of phosphate and nitrate: A critical review[J]. Carbohydrate Polymers, 2021, 274: 118671.

[9] Makay S E, Malherbe F, Eldridge D S . et al. Quaternary amine functionalized chitosan for enhanced adsorption of low concentration phosphate to remediate environmental eutrophication[J]. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2022, 653: 129984.

[10] Liu X, Zhao X, Liu Y, et al. Review on preparation and adsorption properties of chitosan and chitosan composites[J]. Polymer Bulletin, 2022, 79(4): 2633-2665.

[11] Khodaverdi K, Mozafari M, Naghib M S, et al. Chitosan/Bioglass nanocomposites for bone tissue engineering and regenerative medicine: An overview of promising biomaterials[J]. Current Organic Chemistry, 2024, 28(18): 1437-1451.

[12] Nuryono N, Sukamto S, Kunarti E S, et al. Magnetically separable silica-chitosan hybrids for efficient phosphate adsorption in aqueous solution[J]. Case Studies in Chemical and Environmental Engineering, 2025, 11: 101100.

[13] Chauhan I, Mohanty P . In situ decoration of TiO ₂ nanoparticles on the surface of cellulose fibers and study of their photocatalytic and antibacterial activities [J]. Cellulose, 2015, 22(1): 507-519.

[14] Manyatshe A, Cele Z E, Balogun M O, et al. Chitosan modified sugarcane bagasse biochar for the adsorption of inorganic phosphate ions from aqueous solution[J]. Journal of Environmental Chemical Engineering, 2022, 10(5): 108243.

[15] Zhang Y, Gao T, Liu A, et al. Deep removal of phosphate from electroplating wastewater using novel Fe-MOF loaded chitosan hydrogel beads[J]. Journal of Environmental Management, 2024, 357: 120725.

[16] Mahaninia M H, Wilson L D . Cross‐linked chitosan beads for phosphate removal from aqueous solution[J]. Journal of Applied Polymer Science, 2016, 133(5).

[17] Koh K Y, Chen Z, Zhang S, et al. Cost-effective phosphorus removal from aqueous solution by a chitosan/lanthanum hydrogel bead: Material development, characterization of uptake process and investigation of mechanisms[J]. Chemosphere, 2022, 286: 131458.

[18] Eitaweil A S, Ibrahim K, Abd Ei-monaem E M, et al. Phosphate removal by Lanthanum-doped aminated graphene oxide@ aminated chitosan microspheres: Insights into the adsorption mechanism [J]. Journal of Cleaner Production, 2023, 385: 135640.

[19] 国家环境保护局. GB/T11893-1989 水质总磷的测定钼酸铵分光光度法[S]. 北京: 中国环境出版社, 1989.

[20] Mahmoud G, Abdel Khalek M, Shoukry E, et al. Removal of phosphate ions from wastewater by treated hydrogel based on chitosan[J]. Egyptian Journal of Chemistry, 2019, 62(8): 1537-1549.

[21] Xushan C, Huimin Z, Xin Y, et al. Preparation and application of quaternized chitosan- and AgNPs-base synergistic antibacterial hydrogel for burn wound healing[J]. Molecules, 2021, 26(13): 4037- 4037.

[22] Anaya-esparza M L, Ruvalcaba-gomez M J, Maytorena-verdugo I C, et al. Chitosan-TiO ₂: A versatile hybrid composite [J]. Materials, 2020, 13(4): 811.

[23] Karthikeyan P, Banu H A T, Meenakshi S . et al. Synthesis and characterization of metal loaded chitosan-alginate biopolymeric hybrid beads for the efficient removal of phosphate and nitrate ions from aqueous solution[J]. International Journal of Biological Macromolecules, 2019, 130: 407-418.

[24] Saslow S A, Cordova E A, Escobedo N M, et al. Accumulation mechanisms for contaminants on weak-base hybrid ion exchange resins[J]. Journal of Hazardous Materials, 2023, 459: 132165.

[25] Zhan Y, Zhang H, Lin J, et al. Role of zeolite's exchangeable cations in phosphate adsorption onto zirconium-modified zeolite[J]. Journal of Molecular Liquids, 2017, 243: 624-637.

[26] Niroshika K P , Sok K , Deshani A I , et al. Fe(III) Loaded chitosan-biochar composite fibers for the removal of phosphate from water[J]. Journal of Hazardous Materials, 2021, 415: 125464.

基金资助

江苏省海洋资源开发技术创新中心海洋科技项目(LWKJ-02)

江苏省海洋科技创新专项项目(HY2018-10)

江苏省“333 工程”高层次人才资助项目(BRA2014111)

连云港市“521 高层次人才培养工程”资助项目(LYG52105-2018028)