In this study, we prepared 3-aminopropyl-triethoxysilane (APTEOS) functionalized sodium alginate (SA)
porous membrane adsorbent (APTEOS/SA) and tested its adsorption performance for removing of Cr(III)
ions. The physico-chemical properties of the pristine and Cr(III) ions loaded APTEOS/SA were investigated
by FT-IR, SEM-EDX, TG, AFM, and contact angle goniometer methods. To investigate the adsorption
kinetics of Cr(III) ions onto this newly developed APTEOS/SA, we performed a batch of experiments under
different adsorption conditions: solution pH, adsorbent dose, initial Cr(III) ion concentration, adsorption
temperature, and contact time. The APTEOS/SA exhibited an encouraging uptake capacity of 90.0 mg/g
under suitable adsorption conditions. To study the mechanism of adsorption process, we examined
the Lagergren pseudo-first-order and pseudo-second-order kinetic model, the intra-particular diffusion
model, and the Crank model. Kinetics experiments indicated that the pseudo-first-order model displayed
the best correlation with adsorption kinetics data. The Crank model showed that the intra-particle solute
diffusion was the main rate-controlling step. Furthermore, our adsorption equilibrium data could be
better described by the Freundlich equation. We also carried out consecutive adsorption–desorption
experiments eight times to show that the APTEOS/SA has encouraging adsorption–desorption efficiencies.
The results indicates that the prepared adsorbent is promising for using as an effective and economical
adsorbent for Cr(III) ions removal.


Jian Hua Chen,Hai Tao Xing,Hong Xu Guo,Guo Ping Li,Wen Weng,Shi Rong Hu.


Journal of Hazardous Materials,248-249,285-294(2013)