Irreversible ammonia adsorption on asphaltite bottom ash: A thermodynamic approach

Kosan I., Ustunisik G., ÖNAL M., Sarikaya Y., Bozkurt P. A.

COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS, cilt.626, 2021 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 626
  • Basım Tarihi: 2021
  • Doi Numarası: 10.1016/j.colsurfa.2021.126933
  • Dergi Adı: COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Biotechnology Research Abstracts, Chemical Abstracts Core, Chimica, Compendex, EMBASE, INSPEC
  • Anahtar Kelimeler: Adsorption, Asphaltite ash, Enthalpy, Entropy, Isostere, Isotherm, MINERAL MATTER, SE ANATOLIA, PYROLYSIS, BEHAVIOR, CARBON, COAL, SULFUR, CHARS
  • Ankara Üniversitesi Adresli: Evet

Özet

Surface area (20 m(2)g(-1)) and pore volume (0.015 cm(3)g(-1)) estimate for the bottom ash of an asphaltite from Sirnak/Turkey deposit, were determined using the nitrogen adsorption/desorption isotherms at 196 degrees C. The shape and location of the adsorption/desorption isotherms of ammonia on the ash at 0, 50, 100, and 200 degrees C revealed that the irreversible chemical adsorption was more effective than the accompanied physical one. The overall and chemical adsorption capacities increased with the increasing temperature, whereas the physical adsorption capacity decreased. Data obtained from the isotherms, adsorption isosteres, and corresponding Van't Hoff graphs were evaluated thermodynamically to estimate the isosteric enthalpy (Delta H) and entropy changes (Delta S) for the overall ammonia adsorption. Decrease in Delta H and Delta S is caused due to a drop in the endothermic chemical adsorption, whereas increasing exothermic physical adsorption is correlated to the progression of the reaction.