Adsorption of Selected Ions on Ferro-Precipitates from Aqueous Solutions

The main aim of the paper is to evaluate ferro-precipitate as an immobilization agent for various ions from aqueous solutions. Heavy metals, namely lead, copper and chromium were adsorbed as well as arsenate and phosphate. In addition, the adsorption of surfactants, sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CTAB) was carried out. Linear as well as non-linear regression of adsorption isotherms confirmed the Langmuir model applicability. Adsorption capacities (am) were calculated. The highest adsorption capacity was found for arsenate and phosphate respectively (am = 1.36 mmol g−1 for arsenate and 0.70 mmol g−1 for phosphate). Lower but still enough adsorption capacity was found for heavy metals (am = 0.76 mmol g−1 for lead, 0.58 mmol g−1 for copper, 0.38 mmol g−1 for chromium, and the lowest values were shown for surfactants (a = 0.38 mmol g−1 for CTAB and 0.21 mmol g−1 for SDS).