File(s) under permanent embargo
Functionalisation of mesoporous silica gel with 2-[(phosphonomethyl)-amino]acetic acid functional groups. Characterisation and application
journal contribution
posted on 2023-05-18, 02:32 authored by Caldarola, D, Mitev, DP, Marlin, L, Nesterenko, EP, Brett PaullBrett Paull, Onida, B, Bruzzoniti, MC, De Carlo, RM, Sarzanini, C, Nesterenko, PNA new complexing adsorbent was prepared by chemical modification of mesoporous silica Kieselgel 60 (dp = 37–63 μm, average pore size 6 nm, specific surface area 425 m2 g−1) with 3-glycidoxypropyltrimethoxysilane and 2-[(phosphonomethyl)amino]acetic acid (PMA), commonly known as glyphosate. The prepared adsorbent was fully characterised using elemental analysis, thermal gravimetric analysis (TGA), acid–base potentiometric titration, Fourier Transform Infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), nitrogen adsorption isotherms at 77 K (BET), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS). The concentration of bonded PMA groups calculated from the nitrogen content was 0.38 mmol per gram. The adsorption of transition metal ions on PMA functionalised silica (HEPMAS) was studied from aqueous solutions having different pH and the following selectivity was established, Zn(II) < Co(II) < Cd(II) < Mn(II) < Ni(II) < Cu(II). The calculated values of distribution coefficients D for the adsorption of ecotoxic metal ions on HEPMAS are 5.0 × 104, 4.9 × 105 and 2.6 × 104 for Zn(II), Pb(II) and Cd(II), respectively.
History
Publication title
Applied Surface ScienceVolume
288Pagination
373-380ISSN
0169-4332Department/School
School of Natural SciencesPublisher
Elsevier Science BvPlace of publication
PO Box 211, Amsterdam, Netherlands, 1000 AeRights statement
Copyright 2013 Elsevier B.V.Repository Status
- Restricted