Removal of rhodamine B (a basic dye) and thoron (an acidic dye) from dilute aqueous solutions and wastewater simulants by ion flotation.

The present work deals with removal, by ion flotation, of two dyes: a basic dye (rhodamine B (RB)) and an acidic one (thoron (TH)) from dilute aqueous solutions and simulated wastewaters. These dyes are widely used for analytical and biological staining purposes. Besides, RB is commonly used in dyeing of various industrial products.

Removal of catechol from aqueous solutions by adsorption onto organophilic-bentonite.

Organophilic-bentonite, produced by exchange of cetyltrimethylammonium cation for metal cations on the bentonite, was exploited as adsorbent for removal of catechol from aqueous solutions using batch technique. The dependence of removal on various physico-chemical parameters, such as contact time (1-250 min), concentration (0.8-15.

Adsorption of Co2+ and Zn2+ Ions on Hydrous Fe(III), Sn(IV), and Fe(III)/Sn(IV) Oxides.

Thermal analysis has shown that contrary to the case of Zn2+, considerable amounts of water enter in HFO (hydrous ferric oxide), HSO (hydrous stannic oxide), and HMO (hydrous mixed oxide) when Co2+ is adsorbed. A large amount of Co2+ and Zn2+ in all the oxides cannot participate in isotopic exchange, seemingly because of being trapped inside the micropores, a fact hindering oxide capacity determination by isotopic dilution. The % adsorption-pH curves for tracer and 10(-3) M transition metal chloride solutions show a general preference to Zn2+ over Co2+ by all the oxides, in agreement with thermal analysis data.