Adsorption of ni (II) from aqueous solution onto citric acid modified aloe vera (Barbadensis miller) leaf powder / Rohaizan Abdullah

This research investigated the application of biosorbent derived from citric acid modified Aloe Vera (Barbadensis miller) powder (CAALVP) to adsorb cations Ni(II) from aqueous solutions. The biosorbent were characterized by spectroscopic and quantitative analysis. Chemical treatment had successfully changed the physicochemical characteristics of biosorbent such as pHslurry and pHpzc. Elucidation of chemical characteristics of biosorbent surface by Fourier Transfer Infrared (FTIR) spectroscopy reveal different types of functional groups. The performance of biosorbent was affected by pH, biosorbent dosage, initial concentration of the adsorbent and contact time. The adsorption of Ni(II) on biosorbent were best fitted to pseudo-second order kinetic models (R2 > 0.98) and Freundlich isotherm model (R2 > 0.98). However, for Langmuir isotherm, there was only slightly differences between adsorption capacities experimental and calculated which were 37.774 and 48.648 respectively. Meanwhile, for Freundlich there was huge differences between adsorption capacities experimental and calculated which were 39.938 and 8.79 respectively. The best pH and adsorbent dosage for this system were pH 6 and 0.10 g respectively.