Waste newspaper (WNP) is an abundant recyclable cellulose resource, which can be easily collected and purified to prepare high value-added bioadsorbents. In this study, a novel cellulosic filter paper (IMNP) was fabricated from WNP by ultrasonic deinking, wet-papermaking and chemical modification with a specific amino-based imidazolium salt. The prepared IMNP not only displayed good three-dimensional network interweaving structure, but also showed abundant imidazolium functional groups on its surface. Therefore, when IMNP was utilized to the treatment of the critical polluting agent Cr(VI) (hexavalent chromium), it could exhibit an excellent adsorption capacity of 129.3 ± 4.4 mg g⁻¹. Moreover, a high removal rate of 97.9% after three filtrations was achieved. Besides, the adsorption mechanism was investigated by model fitting method of kinetic and isotherm. Meanwhile, by combining with the characterization analysis of materials after adsorption, the results demonstrated the separation of Cr(VI) by IMNP involving complex multiple interactions as well as redox process of transforming Cr(VI) into low-toxic trivalent chromium. Consequently, the application of this high-efficiency filter paper bioadsorbent conforms to the trend and requirement of sustainable development and environmental protection.

废报纸（WNP）是一种丰富的可回收纤维素资源，可以轻松收集和纯化以制备高附加值的生物吸附剂。在这项研究中，由WNP通过超声脱墨，湿法造纸和用特定的氨基咪唑鎓盐进行化学改性，制造了一种新型的纤维素滤纸（IMNP）。制备的IMNP不仅表现出良好的三维网络交织结构，而且在其表面上还显示出丰富的咪唑官能团。因此，当IMNP用于处理关键污染剂Cr（VI）（六价铬）时，它具有129.3±4.4 mg g ^-1的优异吸附能力。。而且，在三个过滤之后，达到了97.9％的高去除率。此外，通过动力学和等温线模型拟合方法研究了吸附机理。同时，结合吸附后材料的表征分析，结果表明IMNP分离Cr（VI）涉及复杂的多重相互作用，并且氧化还原过程将Cr（VI）转化为低毒的三价铬。因此，这种高效滤纸生物吸附剂的应用符合可持续发展和环境保护的趋势和要求。