Synthesis of grafted natural pozzolan with 3-aminopropyltriethoxysilane: preparation, characterization, and application for removal of Brilliant Green 1 and Reactive Black 5 from aqueous solutions

Environ Sci Pollut Res Int. 2017 Sep;24(27):21807-21820. doi: 10.1007/s11356-017-9825-4. Epub 2017 Aug 3.

Abstract

Natural pozzolan is an amorphous silicate-based material of volcanic origin. In this work, the natural pozzolan was modified by using 3-aminopropyltriethoxysilane (APTES) as a grafting agent. This material was characterized by pHpzc, N2 adsorption/desorption curves, FTIR, TGA/DTG, DRUV, SEM, and elementary analysis. The functionalized materials were used for the removal of Reactive Black 5 (RB-5) and Brilliant Green 1 (BG-1) dyes from aqueous solutions using batch-contact adsorption. The characterization of modified pozzolan by FTIR, TGA/DTG, BET, and DRUV-vis revealed the effectiveness of grafting of amine functional group on pozzolan structure. The kinetic adsorption data were better fitted with general order for both dyes while for equilibrium models were better fitted by the Liu isotherm model. The maximum sorption capacities Q max (at 50 °C) obtained with the modified pozzolan were 350.6 and 300.9 mg g-1 for BG-1 and RB-5, at pH 9.0 and 2.0, respectively. The thermodynamic parameters show that the removal of dyes was spontaneous and endothermic. The modified material was also tested for the treatment of simulated dye house effluents showing very high efficiency.

Keywords: 3-Aminopropyltriethoxysilane (APTES); Adsorption; Dyes; Natural pozzolan; Nonlinear fitting; Thermodynamic of adsorption.

MeSH terms

  • Adsorption
  • Coloring Agents / chemistry
  • Hydrogen-Ion Concentration
  • Kinetics
  • Naphthalenesulfonates / isolation & purification*
  • Propylamines / chemistry*
  • Quaternary Ammonium Compounds / isolation & purification*
  • Silanes / chemistry*
  • Solutions
  • Thermodynamics
  • Water
  • Water Pollutants, Chemical / chemistry

Substances

  • Coloring Agents
  • Naphthalenesulfonates
  • Propylamines
  • Quaternary Ammonium Compounds
  • Silanes
  • Solutions
  • Water Pollutants, Chemical
  • Water
  • brilliant green
  • amino-propyl-triethoxysilane
  • Remazol black B