TY - JOUR
T1 - Surface complexation of nickel on iron and aluminum oxides
T2 - A comparative study with single and dual site clays
AU - Rajapaksha, Anushka Upamali
AU - Vithanage, Meththika
AU - Weerasooriya, R.
AU - Dissanayake, C. B.
PY - 2012/7/5
Y1 - 2012/7/5
N2 - Ni adsorption on various single and dual site clays (gibbsite, goethite, natural red earth and leterite) was determined using batch experiments as a function of pH, background electrolyte concentration and adsorbate loading. The experimental data was quantified by 2-pK surface complexation modeling using monodentate and bidentate surface reactions. Gibbsite and laterite showed higher retention of Ni compared to natural red earth (NRE) and goethite indicating high affinity to AlOH surface sites of all clays. The maximum adsorption density of 9.0×10-5molm-2 was reported for gibbsite. All four sorbents showed a negligible variation with ionic strength. The Ni adsorption capacity, i.e., ΓNi, varied with the type of sorbents used in accordance with the following order: ΓGibbsite Ni>ΓLaterite Ni>ΓNRE>ΓGoethite Ni. In all cases, the estimated Gibb's free energy parameter showed that the Ni(II) adsorption was spontaneous.
AB - Ni adsorption on various single and dual site clays (gibbsite, goethite, natural red earth and leterite) was determined using batch experiments as a function of pH, background electrolyte concentration and adsorbate loading. The experimental data was quantified by 2-pK surface complexation modeling using monodentate and bidentate surface reactions. Gibbsite and laterite showed higher retention of Ni compared to natural red earth (NRE) and goethite indicating high affinity to AlOH surface sites of all clays. The maximum adsorption density of 9.0×10-5molm-2 was reported for gibbsite. All four sorbents showed a negligible variation with ionic strength. The Ni adsorption capacity, i.e., ΓNi, varied with the type of sorbents used in accordance with the following order: ΓGibbsite Ni>ΓLaterite Ni>ΓNRE>ΓGoethite Ni. In all cases, the estimated Gibb's free energy parameter showed that the Ni(II) adsorption was spontaneous.
KW - Diffuse double layer model
KW - Gibbsite
KW - Goethite
KW - Laterite
KW - Natural red earth
UR - http://www.scopus.com/inward/record.url?scp=84861697255&partnerID=8YFLogxK
U2 - 10.1016/j.colsurfa.2012.05.001
DO - 10.1016/j.colsurfa.2012.05.001
M3 - Article
AN - SCOPUS:84861697255
SN - 0927-7757
VL - 405
SP - 79
EP - 87
JO - Colloids and Surfaces A: Physicochemical and Engineering Aspects
JF - Colloids and Surfaces A: Physicochemical and Engineering Aspects
ER -