Application of Clay Minerals and Polymeric Resins to Remove Dissolved Microcystin-LR from Water

Document Type : Original Research Paper


Departamento de Ciências Naturais, Instituto de Biociências, Universidade Federal do Estado do Rio de Janeiro - UNIRIO, Avenida Pasteur 458, 22290-240 Rio de Janeiro, Brazil


This study aimed to develop techniques for purification of cyanotoxins dissolved in water -
particularly those produced by Microcystis aeruginosa species - using natural clay, chemically modified
natural clay, commercial clay and ion exchange and adsorbent resins. Except for natural clay, chemical pretreatment was required to increase the adsorption capacity of the treatment materials. All the clays were
exposed to microcystin solutions of 0.5x10-3, 1.0x10-3 and 10.0x10-3 ?g/mL in batch purification processes. The same solutions were used in purification processes with polymeric resins packed in columns. The microcystin- LR samples were quantified using ELISA immunoassay and removal capabilities and saturation of the treatment materials were evaluated. The modified clays showed a microcystin-LR removal efficiency rate between 82.90% and 99.86%, while the resins a rate between 87.6% and 99.74%. This study shows that the materials have technologically and economically promising properties for the removal of microcystins from water.