Investigation of Chromium (III) Adsorption on Acid‑Treated Bentonite Evaluation of Kinetic/Thermodynamic Data

Çınar Acar B., Yüksekdağ Z.

WATER, AIR AND SOIL POLLUTION : AN INTERNATIONAL JOURNAL OF ENVIRONMENTAL POLLUTION, sa.234, ss.716-735, 2023 (SCI-Expanded)

  • Yayın Türü: Makale / Tam Makale
  • Basım Tarihi: 2023
  • Doi Numarası: 10.1007/s11270-023-06727-5
  • Dergi Adı: WATER, AIR AND SOIL POLLUTION : AN INTERNATIONAL JOURNAL OF ENVIRONMENTAL POLLUTION
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, ABI/INFORM, Agricultural & Environmental Science Database, Aqualine, Aquatic Science & Fisheries Abstracts (ASFA), Artic & Antarctic Regions, BIOSIS, Biotechnology Research Abstracts, CAB Abstracts, Chemical Abstracts Core, Chimica, Compendex, Environment Index, Geobase, Greenfile, Pollution Abstracts, Veterinary Science Database, Civil Engineering Abstracts
  • Sayfa Sayıları: ss.716-735
  • Gazi Üniversitesi Adresli: Evet

Özet

Sorption studies were carried out in a batch system using Cr(III) solution on non-treated and acid-treated white-colored calcium-bentonite (WCa-B). WCa-B, which has the highest cation exchange capacity (119 meq/100 g), was treated with 2 dif-ferent acids (H2SO4 and HCl) at various concentra-tions. The surface area was increased approximately 5 times (493 m2/g) without causing deterioration in the crystal structure of bentonite with 1.0M H2SO4 activation. To determine the chemical and mineral-ogical composition of the adsorbent, which was char-acterized with XRD, XRF, Surface Area and Porosity, TG/DTA, FT-IR, SEM, and EDX. For Cr(III) uptake experiments, a batch method was applied. The highest Cr(III) monolayer adsorption capacity was specified as 219.8mg/g. To Cr(III) adsorption, ΔH°, ΔS°, and ΔG° were designated onto adsorbent and it was found that adsorption is coherent with Langmuir monolayer isotherm, adsorption has an endothermic character, and has spontaneously occurred. By using pseudo-second-order and Lagergren kinetic models, Cr(III) adsorptions kinetic experiments were determined, it was designated that the adsorption was exhibited to be proper for the pseudo-second-order kinetic model.