Adsorption interaction between natural adsorbents and textile dyes in aqueous solution

Agricultural wastes from maize culture fields were prepared and activated yielding the natural absorbents designated as SOMAP SOMAP 1, SOMAP2, HELAP, HELAP1, SAGAP, and SAGAP1. The samples were further characterized using microscopy, FTIR spectroscopy, titration, and adsorption from solution. The dry and wet methods of analysis confirmed the presence of functional groups (hydroxyl, carboxylic, phenolic, and lactonic) in the bulk and on the surface, respectively. Each prepared solid sample was tested for adsorption ability using aqueous dye solutions of basic blue 41 (131341), acid blue 74 (AB74), and reactive black 5 (RB5). The adsorption affinity decreased according to BB41>AB74>RB5. For BB41 the relative adsorbent saturation followed the series: SOMAP2