KINETICKS AND ISOTHERMS OF ACID ORANGE 7 ADSORPTION FROM AQUEOUS SOLUTIONS BY NANOSIZED IRON OXIDE IMMOBILIZED ON PERLITE

In this work, the iron oxide immobilized on perlite (NIO-P) as an adsorbent was prepared. Adsorption kinetics of acid orang 7 (AO7) at different amount ofNIO-P (m), initial concentration of AO7 (C0), pH and temperature (T) were studied over 90 min adsorption periods. The obtained data were treated according totow various rate models. Our results showed the pseudo second order model was the most suitable on the all conditions. Our results showed that theadsorption rate constants for pseudo second order model decreasing order: m=0.8>0.6>0.4>0.2>0.1g, T=15>20>25>30>35 ◦C, pH=5>6>7>8>9 and C0=15>20>25>30=35 mg.l-1. However, the isotherm data were treated according to Langmuir andFreundlich models. The adsorption data at 25 oCwere found to fit almost equally well to Freundlich model.