TY - JOUR
T1 - Adsorption studies on the removal of Malachite Green from aqueous solutions onto halloysite nanotubes
AU - Kiani, Gholamreza
AU - Dostali, Mohammad
AU - Rostami, Ali
AU - Khataee, Ali R.
PY - 2011/11
Y1 - 2011/11
N2 - Halloysite nanotubes (HNTs) were used as nano-adsorbents for removal of the cationic dye, Malachite Green (MG), from aqueous solutions. The adsorption of the dye was studied with batch experiments. The natural HNTs used as adsorbent in this work were initially characterized by FT-IR and TEM. The effects of adsorbent dose, initial pH, temperature, initial dye concentration and contact time were investigated. Adsorption increased with increasing adsorbent dose, initial pH, and temperature. Equilibrium was rapidly attained after 30min of contact time. Pseudofirst-order, pseudo-second-order and intraparticle diffusion models were considered to evaluate the rate parameters. The adsorption followed pseudo-second-order kinetic model with correlation coefficients greater than 0.999. The factors controlling adsorption process were also calculated and discussed. The maximum adsorption capacity of 99.6mgg-1 of MG was achieved in pH=9.5. Thermodynamic parameters of δG°, δH° and δS° indicated the adsorption process was spontaneous and endothermic.
AB - Halloysite nanotubes (HNTs) were used as nano-adsorbents for removal of the cationic dye, Malachite Green (MG), from aqueous solutions. The adsorption of the dye was studied with batch experiments. The natural HNTs used as adsorbent in this work were initially characterized by FT-IR and TEM. The effects of adsorbent dose, initial pH, temperature, initial dye concentration and contact time were investigated. Adsorption increased with increasing adsorbent dose, initial pH, and temperature. Equilibrium was rapidly attained after 30min of contact time. Pseudofirst-order, pseudo-second-order and intraparticle diffusion models were considered to evaluate the rate parameters. The adsorption followed pseudo-second-order kinetic model with correlation coefficients greater than 0.999. The factors controlling adsorption process were also calculated and discussed. The maximum adsorption capacity of 99.6mgg-1 of MG was achieved in pH=9.5. Thermodynamic parameters of δG°, δH° and δS° indicated the adsorption process was spontaneous and endothermic.
KW - Halloysite nanotubes
KW - Kinetic model
KW - Nano-adsorbent
KW - Textile dye
KW - Thermodynamic parameter
UR - http://www.scopus.com/inward/record.url?scp=80053308519&partnerID=8YFLogxK
U2 - 10.1016/j.clay.2011.07.008
DO - 10.1016/j.clay.2011.07.008
M3 - Article
AN - SCOPUS:80053308519
SN - 0169-1317
VL - 54
SP - 34
EP - 39
JO - Applied Clay Science
JF - Applied Clay Science
IS - 1
ER -