State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, PR China; Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, PR China.
State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, PR China; Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, PR China.
J Colloid Interface Sci. 2020 Sep 1;575:78-87. doi: 10.1016/j.jcis.2020.04.079. Epub 2020 Apr 20.
Simultaneous enhancement in water flux and removal efficiency during the filtration process remains a big challenge for separation membranes. The porous structure of the filter paper can provide many channels for water transportation, but the separation performance is generally poor. The purpose of this study is to develop a new kind of filter paper consisting of ultralong hydroxyapatite (HAP) nanowires, cellulose fibers (CFs) and double metal oxide (LDO) nanosheets, and to achieve the simultaneous enhancement of both water flux and removal efficiency for high-performance dye separation. In this work, a novel kind of LDO/HAP/CF nanocomposite filter paper consisting of ultralong HAP nanowires and CFs and LDO nanosheets has been developed for rapid water filtration and highly efficient dye adsorption. Positively charged LDO nanosheets can adsorb on the surface of negatively charged ultralong HAP nanowires and embed in the porous networked structure of the LDO/HAP/CF nanocomposite filter paper, which can provide a porous structure for rapid water transportation and can adjust the pore size of the nanocomposite filter paper. As a result, the pure water flux of the LDO/HAP/CF nanocomposite filter paper can be adjusted. The optimized pure water flux of the LDO/HAP/CF nanocomposite filter paper can reach 783.6 L m h bar, which is 1.51 times that of the HAP/CF filter paper without LDO nanosheets (518.6 L m h bar). More importantly, the adsorption capacity of LDO nanosheets is high for dye molecules, the rejection percentage of Congo red (CR) by the as-prepared HAP/CF filter paper is only 59.8%, and its water flux is 534.7 L m h bar. The optimized rejection percentage and water flux of the LDO/HAP/CF nanocomposite filter paper for CR are significantly enhanced (98.3% and 736.8 L m h bar, respectively) compared to those of the HAP/CF filter paper. The size of LDO nanosheets has a significant effect on the water flux and dye rejection percentage of the LDO/HAP/CF nanocomposite filter paper. The as-prepared LDO/HAP/CF nanocomposite filter paper is promising for the applications in highly efficient purification of wastewater containing dye molecules.
在过滤过程中同时提高水通量和去除效率仍然是分离膜面临的一大挑战。滤纸的多孔结构可为水的输送提供许多通道，但分离性能通常较差。本研究的目的是开发一种由超长羟基磷灰石（HAP）纳米线、纤维素纤维（CF）和双金属氧化物（LDO）纳米片组成的新型滤纸条，以同时提高水通量和去除效率，从而实现高性能染料分离。在这项工作中，开发了一种由超长 HAP 纳米线和 CF 以及 LDO 纳米片组成的新型 LDO/HAP/CF 纳米复合滤纸，用于快速水过滤和高效染料吸附。带正电荷的 LDO 纳米片可以吸附在带负电荷的超长 HAP 纳米线表面上，并嵌入 LDO/HAP/CF 纳米复合滤纸的多孔网络结构中，这为快速水输送提供了多孔结构，并可以调节纳米复合滤纸的孔径。因此，可以调节 LDO/HAP/CF 纳米复合滤纸的纯水通量。优化后的 LDO/HAP/CF 纳米复合滤纸的纯水通量可达 783.6 L m h bar，是没有 LDO 纳米片的 HAP/CF 滤纸（518.6 L m h bar）的 1.51 倍。更重要的是，LDO 纳米片对染料分子具有高的吸附能力，所制备的 HAP/CF 滤纸对刚果红（CR）的截留率仅为 59.8%，其水通量为 534.7 L m h bar。与 HAP/CF 滤纸相比，优化后的 LDO/HAP/CF 纳米复合滤纸对 CR 的截留率和水通量分别显著提高（分别为 98.3%和 736.8 L m h bar）。LDO 纳米片的尺寸对 LDO/HAP/CF 纳米复合滤纸的水通量和染料截留率有显著影响。所制备的 LDO/HAP/CF 纳米复合滤纸有望在高效净化含有染料分子的废水方面得到应用。
