Urtica dioica leaves-calcium alginate as a natural, low cost and very effective bioadsorbent beads in elimination of dyes from aqueous medium: Equilibrium isotherms and thermodynamic studies.

A very effective and low cost bioadsorbents derived from Urtica dioica leaf powder (UDL) and composite beads UDL encapsulated with calcium alginate (UDL/A) were used in removal of cationic dye crystal violet (CV) from aqueous medium. The new adsorbents were characterized by Fourier transform infrared spectroscopy (FTIR) and isoelectric points (pHpzc). Adsorption was studied in batch system according to initial CV concentration (30-150 mg/L), contact time, pH (2-11), temperature (10 to 40 °C) and adsorbent mass (10 to 200 mg).

Preparation and characterization of new low cost adsorbent beads based on activated bentonite encapsulated with calcium alginate for removal of 2,4-dichlorophenol from aqueous medium.

This study explored the potential of composites organo-bentonite/alginate beads as adsorbents for the removal of 2,4-dichlorophenol (2,4DCP) from aqueous solution. Bentonite was firstly modified with cationic surfactants octadecyltrimethylammonium, hexadecyl trimethylammonium and phenyltrimethylammonium, then encapsulated with calcium alginate to form adsorbent composite beads. X-ray diffraction was used to study the change in the structural properties of the samples.