Ji Yuanhuo, Wang Xiwen
School of Light Industry Science and Engineering, South China University of Technology, No. 381 Wushan Road, Tianhe District, Guangzhou, 510641, Guangdong, China.
Environ Sci Pollut Res Int. 2023 Feb;30(9):23372-23385. doi: 10.1007/s11356-022-23833-9. Epub 2022 Nov 2.
A heavy metal ion adsorbent (HFPANF) with high surface area was obtained from polyacrylonitrile fibers with fibrillation and alkali hydrolysis, and an activated carbon fiber filter was prepared by using HFPANF as the binder. The surface area of polyacrylonitrile was 48.64 m/g due to fibrillation, which also led to the carboxyl content of the HFPANF up to 3.4 mmol/g. Batch adsorption experiments on Cu and Pb showed that the adsorption capacities of HFPANF for Cu and Pb were 47.5 mg/g and 54.3 mg/g. The adsorption kinetics showed that the adsorption reached equilibrium at 90 min and that the adsorption followed the pseudo-second order model. It indicates that the adsorption process is chemisorption. HFPANF formed a single tooth chelate with Cu and a double tooth chelate with Pb. HFPANF-ACF filter was prepared by wet molding technique. When the HFPANF content was 30%, the filter reached a compressive strength of 15.37 MPa and its maximum flux was 180 L/h. 2.5 mg/L of Cu and Pb were used for dynamic adsorption experiments and the heavy metal removal rate was still above 95% after filtering 600 L. The pressure drop of HFPANF-ACF filter was much smaller compared with that of GAC filter due to the combined effect of fibrillated nanofibers and ACF, which can improve the filtration efficiency of the filter.
通过对聚丙烯腈纤维进行原纤化和碱水解，获得了具有高比表面积的重金属离子吸附剂（HFPANF），并以HFPANF为粘结剂制备了活性炭纤维过滤器。由于原纤化，聚丙烯腈的比表面积为48.64 m²/g，这也使得HFPANF的羧基含量高达3.4 mmol/g。对铜和铅的批量吸附实验表明，HFPANF对铜和铅的吸附容量分别为47.5 mg/g和54.3 mg/g。吸附动力学表明，吸附在90分钟时达到平衡，且吸附遵循准二级模型。这表明吸附过程是化学吸附。HFPANF与铜形成单齿螯合物，与铅形成双齿螯合物。采用湿成型技术制备了HFPANF-ACF过滤器。当HFPANF含量为30%时，过滤器的抗压强度达到15.37 MPa，最大通量为180 L/h。使用2.5 mg/L的铜和铅进行动态吸附实验，过滤600 L后重金属去除率仍高于95%。由于原纤化纳米纤维和ACF的共同作用，HFPANF-ACF过滤器的压降比GAC过滤器小得多，这可以提高过滤器的过滤效率。
