## 4 Conclusions  
This study reported the use of the electrospinning technique to combine and incorporate silica-supported 2-aminomethylpyridine (SiAMPy) into polyethylene terephthalate (PET) and waste plastic bottles (WPET) polymer solutions to produce composite nanofibres (PET-SiAMPy and WPET-SiAMPy) for the first time to our knowledge. The PET and WPET nanofibres were robust with very fine dimensions and a high surface area-to-volume ratio, which makes them ideal for active adsorbent support. In batch adsorption experiments, PET-SiAMPy or WPET-SiAMPy composite nanofibres achieved Cu\({}^{2+}\) adsorption equilibrium within 60 s of contact time with 0.98 mmol/g (89.87%) or 1.24 mmol/g (96.04%) Cu\({}^{2+}\) adsorption capacity. WPET-SiAMPy composite nanofibres were found to be effective adsorbents for the recovery of Cu\({}^{2+}\) ion from aqueous solution, as the WPET-SiAMPy composite nanofibres carried sufficient Cu\({}^{2+}\) adsorption active sites. The rapid kinetics and high Cu\({}^{2+}\) recovery was credited to the high surface area and the porosity of the PET-SiAMPy or WPET-SiAMPy composite nanofibres, which resulted in more adsorption sites being available for the Cu metal ion adsorption from the solution. The application of the WPET-SiAMPy composite electrospun nanofibres for Cu\({}^{2+}\) adsorption with very fast kinetic provides high-performance Cu\({}^{2+}\) adsorbent that is distinctive to this research. The regeneration of WPET-SiAMPy composite nanofibres allowed replicable high Cu\({}^{2+}\) readsorption proving the reusability of the WPET-SiAMPy composite nanofibres, compared to the silica-supported 2-aminomethylpyridine resin (AMPy). The deteriorating limit of the WPET-SiAMPy composite nanofibres should be studied to establish the extent of the regeneration of WPET-SiAMPy composite nanofibres in future studies. [PERSON], [PERSON] and [PERSON] conceptualized, validated, and formally analysed the manuscript. [PERSON] drafted the methodology, investigated, performed the data curation, and prepared the original draft. [PERSON] and [PERSON] reviewed and edited the manuscript. [PERSON] administered the project, organized resources, reviewed, edited, visualized, supervised, and acquired funding for the research project. All authors have read and agreed to the published version of the manuscript. The study was supported by Environmental and Nano Sciences Research Group, University of the Western Cape, South Africa; Research Foundation of the Lappeenranta-Lahti University of Technology LUT; and Academy of Finland. Not applicable. The data presented in this study are available within the article. A.J. * [PERSON] et al. (2019) [PERSON]; [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON] Fabrication and characterisation of novel nanofiltration polymeric membrane. _Mater. Today Commun._**2019**, _20_, 100580. [CrossRef]
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