Synthesis and Characterization of TiO₂Modified with Polystyrene and Poly(3-chloro-2-hydroxypropyl Methacrylate) as Adsorbents for the Solid Phase Extraction of Organophosphorus Pesticides

Abstract

Novel hybrid TiO2particles were developed and assessed as an adsorbent for solid phase extraction (SPE) of organophosphorus pesticides (fensulfothion, parathion methyl, coumaphos, and diazinon) from spiked water. The sol-gel method was used to synthesize TiO2particles, which were coated with free-radical polystyrene (PS) and poly(3-chloro-2-hydroxypropyl methacrylate) (PClHPMA) polymers. Particle structures were determined via Fourier transform infrared spectroscopy to confirm that the polymers were successfully anchored to the TiO2particles. Thermogravimetric analysis was conducted to determine organic and inorganic matter in TiO2-PS and TiO2-PClHPMA particles showing results of 20 : 80 wt/wt% and 23 : 77 wt/wt%, respectively. SEM-EDS and X-ray diffraction test were conducted to determine the morphology and semielemental composition of the particles showing amorphous characteristics. By observing the contact angle, particles coated with PClHPMA were determined to be more hydrophilic than TiO2-PS particles. The pore size distributions obtained from the N2adsorption-desorption isotherms were 0.150 and 0.168 cm3g−1. The specific surface area (BET) was 239.9 m2g−1for TiO2-PS and 225.7 m2g−1for TiO2-PClHPMA. The synthesized particles showed relatively high yields of adsorption in SPE. The pesticide recoveries obtained by high performance liquid chromatography ranged from 6 to 26% for TiO2-PClHPMA and 44 to 92% for TiO2-PS.

Preparation of TiO2-Poly(3-Chloro-2-Hydroxypropyl Methacrylate) Nanocomposite for Selective Adsorption and Degradation of Dyes

“…In the course of our study, TiO 2 -PCHPMA was synthesized and examined for removal of organophosphorus pesticides for comparison with TiO 2 modified with polystyrene [55]. However, this TiO 2 -PCHPMA showed weaker interaction with the examined pesticides than the polystyrene analogue.…”

Synthesis of block copolymers containing 3-chloro-2-hydroxypropyl methacrylate by NMP – a versatile platform for functionalization

“…42 A second approach to adsorbent materials based on PClHPMA is provided by Alejo-Molina via the homopolymerization of ClHPMA from vinyl-functionalized TiO 2 . 45 The obtained polymer-coated TiO 2 particles showed good suitability for the adsorption of organophosphorus pesticides. Further on, PClHPMA served as basis for the attachment of 5,5-dimethylhydantoin.…”

Detailed Study on Rapid Removal of Cationic Dyes Using TiO2-Poly(3-Chloro-2-Hydroxypropyl Methacrylate) Nanocomposite

“…The adsorption efficiency of TiO2-PCHPMA toward MB exceeded 99% within 5 min, while anionic methyl orange (MO) was not adsorbed at all. On the other hand, Alejo-Molina et al also examined TiO2-PCHPMA for removal of hydrophobic pesticides by adsorption, and found that TiO2-PCHPMA was less effective than TiO2 modified by polystyrene due to the negligible affinity (59). In this work, we investigated the availability of TiO2-PCHPMA for rapid and selective removal of various cationic dyes under various conditions, and the isotherm model for the adsorption.…”