Fuente: Polymers Polymers, Vol. 18, Pages 150: Cadmium Removal from Synthetic Waste-Water Using TiO2-Modified Polymeric Membrane Through Electrochemical Separation System
Polymers doi: 10.3390/polym18020150
Authors:
Simona Căprărescu
Roxana Gabriela Zgârian
Grațiela Teodora Tihan
Alexandru Mihai Grumezescu
Eugenia Eftimie Totu
Daniel Costinel Petre
Cristina Modrogan

In this paper, a new polymeric membrane including polymers (cellulose acetate, polyethylene glycol 400), copolymer poly(4-vinylpyridine)-block-polystyrene, and TiO2 nanoparticles were synthesized by the phase inversion method. In order to investigate the presence and the influence of the TiO2 nanoparticles on the membrane matrix, a polymeric membrane without TiO2 nanoparticles was prepared by the same preparation method. The structure of the polymeric membranes was characterized by several techniques, such as Fourier transform infrared spectroscopy and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy, thermogravimetric analysis, and impedance spectroscopy. Also, the water contact angle, water retention, and porosity were determined. The results showed that the TiO2 nanoparticles were incorporated into the pores and onto the surface of the polymeric membrane, which resulted in a more uniform structure. In addition, these polymeric membranes were tested for the removal of cadmium ions from synthetic waste-water using a laboratory-scale electrochemical separation system with a custom-built setup. The results showed that the polymeric membrane with TiO2 nanoparticles showed a high cadmium ions removal rate (95.53%), compared to the polymeric membrane without TiO2 nanoparticles (85.29%), after a 1.5 h electrochemical separation test. The final results indicated that the polymeric membranes prepared with TiO2 nanoparticles had excellent thermal stability and exhibited the best ionic conductivity. The electrochemical separation system proved that the obtained polymeric membranes effectively remove cadmium from the synthetic waste-water.