(181v) Removal of Hg2+ from Polluted Water Using Molecularly Ion-Imprinted Silica Particles (MIIP) As Fibrous Composite with Polysulfone Matrix

Wastewater containing mercury is still improperly released in large amounts by different industrial facilities. A more attractive way to remove mercury ions (Hg²⁺) from aqueous water is through the preparation of molecularly ion imprinted particle (MIIP), which introduces ion-recognition sites into the polymeric materials to have high selectivity with the target metal ion. However, most of the prepared MIIP sorbents are in powder form that can lead to poor regeneration, thus, limiting their application for continuous and recyclable adsorption process.

Herein, Hg-MIIP composite nanofiber (NF) was prepared by incorporating MIIP from dithizone (DTZ)-Hg²⁺ complex in polysulfone (PSf) as polymeric support. Hg-MIIP was synthesized via sol-gel process by chelating DTZ with Hg²⁺followed by growth of silica phase (SiO­₂), which serves as the bulk material for the templated structure. Dope solution of Hg-MIIP/PSf was then electrospun to produce the nanofibers. Hg²⁺ was acid-leached to prepare the activated MIIP immobilized in the PSf NF. The MIIP/PSf NF adsorbent was evaluated using different characterization techniques such as SEM-EDS, BET, thermogravimetric analysis, capillary flow porometry, and mechanical testing. Results showed that the static adsorption of Hg²⁺ on MIIP/PSf NF adsorbent was Langmuir-type while its rate of adsorption is adequately described by pseudo-second order rate model. Moreover, it presents excellent selectivity towards Hg²⁺, good stability, and reusability, which demonstrates its practical application for Hg²⁺ sequestration for wastewater treatment.

This research was supported by the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT (No. 2017R1A2B2002109 and No. 2018R1D1A1B07047503) and by the Ministry of Education (No. 22A20130012051(BK21Plus)).