Simultaneous adsorption of copper ions and humic acid onto an activated carbon

Adsorption of Polycarboxylate-based Superplasticizer onto Natural Bentonite

“…8, the increase in the concentration of NaCl from 0.00-0.10 mol/L caused the increase in adsorption amount of PC from 80.0 to 94.3 mg/g. The increase of adsorption amount with the increase in ionic strength can be explained by several mechanisms: (1) the decrease of molecular size of PC, caused by the increase of ionic strength due to minimalization of the electrostatic repulsion between ionized carboxyl groups, facilitated the adsorption (Chen 2004); (2) ionization of NaCl in the aqueous dispersion binds water molecules and the competition between PC molecules and water molecules for adsorption sites occurred at lower level (Seki 2006); (3) the significant increase in adsorption amount of PC at high ionic strength may be due to loss of the colloidal stability, leading to coagulation and precipitation of the PC and further co-sedimentation with the bentonite particles during the intense centrifugation (Abate 2003); (4) in addition, at higher ionic strength the solubility of PC was lower, favoring the mass transfer of PC from the solution phase to the solid phase of bentonite (Zhou 1994). …”

Adsorption of lead, ethylenediaminetetraacetic acid and lead-ethylenediaminetetraacetic acid complex onto granular activated carbon

“…Krishnan et al (2003) also reported that lead adsorption in the presence of chelating agent was reduced in pH range 6-8. Typically, the granular activated carbon surface is known to have several acidic functional groups including carboxylic, lactonic, hydroxyl, etc., which can be generalized by reaction 1 and reaction 2 as shown below (Barton et al, 1997;Corapcioglu and Huang, 1987;Chen and Wu, 2004):…”

Electrochemically Modified Viscose-Rayon-Based Activated Carbon Cloth for Competitive and Noncompetitive Sorption of Trace Cobalt and Lead Ions from Aqueous Solution

“…However, correlation coefficients for Freundlich isotherm model were higher than those for UO. Freundlich models have been used in modelling metal ions isotherms by several researchers (13,(22)(23)(24)(25). capacities for UO, respectively.…”