Dimercaprol-modified mesoporous silica nanoparticles for efficient removal of toxic mercury ions from aqueous solution

Environ Geochem Health. 2024 Aug 28;46(10):401. doi: 10.1007/s10653-024-02169-y.

Abstract

A surface-modified mesoporous silica nanoparticle containing dimercaprol monomers was created utilizing the sol-gel condensation process, using tetraethyl orthosilicate (TEOS) as the silica source and poloxamer as the structure directing agent. To accomplish this synthesis, 3-glycidoxypropyl triethoxysilane (GPTS, 20 mol%) was incorporated into the silica walls during the sol-gel condensation process, along with TEOS. Furthermore, dimercaprol (DM) monomers were incorporated onto silica surfaces by a ring-opening reaction between GPTS epoxy groups, and dimercaprol hydroxyl groups. The prepared dimercaprol-modified silica adsorbent (MSN-DT NPs) material has been studied using a variety of instruments, including XRD, FT-IR, N2 adsorption-desorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric (TG) analysis, and zeta potential analysis. The MSN-DT NPs material selectively adsorbs mercury ions, with a high adsorption amount of 125 mg/g and a removal capability of roughly ~ 90% from the original metal ion mixture comprising other competing metals such as Pb2+, Ni2+, Fe2+, and Zn2+. The MSN-DT NPs adsorbent shows recyclable qualities for up to five cycles when treated with an acidic aqueous solution (0.1 M HCl). As a result, the MSN-DT NPs adsorbent may be regenerated and reused up to five times without losing its adsorption effectiveness. The experimental findings showed that the MSN-DT NPs adsorbent may be employed to selectively remove hazardous Hg2+ ions from an aqueous solution.

Keywords: Dimercaprol; Metal adsorption; Recyclability; Selective adsorption; Silica nanoparticles; Surface modification.

MeSH terms

  • Adsorption
  • Mercury* / chemistry
  • Microscopy, Electron, Scanning
  • Microscopy, Electron, Transmission
  • Nanoparticles* / chemistry
  • Porosity
  • Silicon Dioxide* / chemistry
  • Spectroscopy, Fourier Transform Infrared
  • Water Pollutants, Chemical* / chemistry
  • Water Purification* / methods
  • X-Ray Diffraction

Substances

  • Silicon Dioxide
  • Water Pollutants, Chemical
  • Mercury