The adsorption kinetics of the cationic dye, methylene blue, onto clay

Gurses A., Dogar C., Yalcın M., Acıkyıldız M., Bayrak R., Karaca S.

JOURNAL OF HAZARDOUS MATERIALS, cilt.131, ss.217-228, 2006 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 131
  • Basım Tarihi: 2006
  • Doi Numarası: 10.1016/j.jhazmat.2005.09.036
  • Dergi Adı: JOURNAL OF HAZARDOUS MATERIALS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.217-228
  • Anahtar Kelimeler: adsorption kinetics, dye, clay, pseudo-first-order kinetics, pseudo-second-order kinetics, intraparticle diffusion, MONOVALENT ORGANIC CATIONS, AQUEOUS-SOLUTION, ACID DYE, COMPETITIVE ADSORPTION, CONTAINING EFFLUENTS, NATURAL ADSORBENTS, ACTIVATED CARBON, BASIC-DYES, FLY-ASH, REMOVAL
  • Atatürk Üniversitesi Adresli: Evet

Özet

In this study, adsorption kinetics of a cationic dye, methylene blue, onto clay from aqueous solution with respect to the initial dye concentration, temperature, pH, mixing rate and sorbent dosage were investigated. In order to understand the adsorption mechanism in detail, zeta potentials and the conductivities of clay suspensions at various pH (1-11) and cation exchange capacity (CEC) were measured. Porosity and BET surface area of clay studied were determined. The results showed that the adsorption has been reached to equilibrium in 1 h. It was found that the amount adsorbed of methylene blue increases with decreasing temperature and also with increasing both sorbent dosage and increasing initial dye concentration. Adsorption capacity decreases with increasing pH, except for the natural pH (5.6) of clay suspensions. The adsorption kinetics of methylene blue has been studied in terms of pseudo-first-order, pseudo-second-order sorption and intraparticle diffusion processes thus comparing chemical sorption and diffusion sorption processes. It was found that the pseudo-second-order mechanism is predominant and the overall rate of the dye adsorption process appears to be controlled by the more than one-step. (c) 2005 Elsevier B.V. All fights reserved.