Composite polyester membranes with embedded dendrimer hosts and bimetallic Fe/Ni nanoparticles: synthesis, characterisation and application to water treatment

• Published in: Journal of nanoparticle research : an interdisciplinary forum for nanoscale science and technology 2013-06, Vol.15 (6), p.1-15, Article 1698
• Main Authors: Malinga, S. P., Arotiba, O. A., Krause, R. W. M., Mapolie, S. F., Diallo, M. S., Mamba, B. B.
• Format: Article
• Language: English
• Subjects: Byproducts; Characterization and Evaluation of Materials; Chemistry and Materials Science; Chlorophenol; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Dechlorination; Dendrimers; Electron, ion, and scanning probe microscopy; Exact sciences and technology; Inorganic Chemistry; Iron; Lasers; Low-dimensional structures (superlattices, quantum well structures, multilayers): structure, and nonelectronic properties; Mass spectrometry; Materials Science; Membranes; Methods of nanofabrication; Nanocrystalline materials; Nanoparticles; Nanoscale materials and structures: fabrication and characterization; Nanotechnology; Nanotechnology for Sustainable Development; Nickel; Optical Devices; Optics; Phenols; Photonics; Physical Chemistry; Physicochemical properties; Physics; Pollutants; Porosity; Research Paper; Scanning probe microscopy: scanning tunneling, atomic force, scanning optical, magnetic force, etc; Structure of solids and liquids; crystallography; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Synthesis; Ultraviolet spectroscopy; Water pollution; Water treatment
• ISSN: 1388-0764; 1572-896X
• DOI: 10.1007/s11051-013-1698-y

This study describes the preparation, characterization and evaluation of new composite membranes with embedded dendrimer hosts and Fe/Ni nanoparticles. These new reactive membranes consist of films of cyclodextrin–poly(propyleneimine) dendrimers (β-CD–PPI) that are deposited onto commercial polysulfone microporous supports and crosslinked with trimesoyl chloride (TMC). The membranes were subsequently loaded with Fe/Ni nanoparticles and evaluated as separation/reactive media in aqueous solutions using 2,4,6-trichlorophenol as model pollutant. The morphology and physicochemical properties of the composite membranes were characterised using high-resolution transmission electron microscopy (HR-TEM), atomic force microscopy and measurements of contact angle, water intake, porosity and water permeability. The sorption capacity and catalytic activity of the membranes were evaluated using ion chromatography, atmospheric pressure chemical ionisation-mass spectrometry and UV–Vis spectroscopy (UV–Vis). The sizes of the embedded Fe/Ni nanoparticles in the membranes ranged from 40 to 66 nm as confirmed by HR-TEM. The reaction rates for the dechlorination of 2,4,6-trichlorophenol ranged from 0.00148 to 0.00250 min −1 . In all cases, we found that the reaction by-products consisted of chloride ions and mixtures of compounds including phenol ( m / z  = 93), 2,4-dichlorophenol ( m / z  = 163) and 4-chlorophenol ( m / z  = 128). The overall results of this study suggest that β-CD–PPI dendrimers are promising building blocks for the synthesis of composite and reactive membranes for the efficient removal of chlorinated organic pollutants from water.