Removal of Th(IV) from aqueous solution with modified silica gel by 4-hydroxy-N '-((thiophen-2-yl) methylene)benzohydrazide schiff base


KIRKAN B. , Demirhan M. N.

SEPARATION SCIENCE AND TECHNOLOGY, 2022 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Publication Date: 2022
  • Doi Number: 10.1080/01496395.2022.2073236
  • Title of Journal : SEPARATION SCIENCE AND TECHNOLOGY
  • Keywords: Th(IV), silica gel, solid phase extraction, schiff base, removal, SOLID-PHASE EXTRACTION, GRAFTED TH(IV)-IMPRINTED POLYMERS, LIQUID-LIQUID MICROEXTRACTION, CLOUD-POINT EXTRACTION, SELECTIVE SEPARATION, SORPTION PROPERTIES, WATER SAMPLES, TRACE AMOUNTS, THORIUM, PRECONCENTRATION

Abstract

In this study, SiCPMS@L solid adsorbent was prepared using 4-Hydroxy-N '- ((Thiophen-2-yl)methylene)benzohydrazide Schiff base for thorium(IV) removal from aqueous solution, and the structure of the solid adsorbent was characterized by FTIR, SEM, elemental analysis, and BET surface analysis methods. Solution pH, initial thorium concentration, contact time, adsorbent dose, and temperature parameters affecting the adsorption of Th(IV) ions with SiCPMS@L adsorbent were examined, and optimum uptake conditions were determined. The effective initial pH for adsorption was found to be 4.0. The binding sites on SiCPMS@L solid adsorbent were saturated using an initial Th(IV) concentration of 16.0 mg/L. 30 minutes was determined as the optimum contact time when the adsorption equilibrium was established. The optimum adsorbent dose for SiCPMS@L was determined as 1.0 g/L. At optimum conditions, adsorption efficiency and adsorption capacity values for SiCPMS@L adsorbent were respectively; 97.4% +/- 0.1 and 15.6 +/- 0.1 mg/g were obtained. The calculated thermodynamic parameters increment S degrees, increment G degrees and increment H degrees showed that the Th(IV) sorption process is thermodynamically advantageous, spontaneous and endothermic. Langmuir, Freundlich and Dubinin-Radushkevich adsorption isotherms for removal of Th(IV) ions with SiCPMS@L solid adsorbent were investigated and found to be compatible with Langmuir isotherm.