Effect of treating a PVC/Aliquat-336 polymer adsorbent with sodium hydroxide on chromium (VI) adsorption

ABSTRACT

A PVC adsorbent doped with Aliquat-336 was prepared with the phase inversion method for application to hexavalent chromium adsorption. Scanning electron microscopy (SEM) and BET analysis were used to identify its morphology and texture. SEM images revealed an asymmetrical structure with a macro-porous interior layer and a thin micro-porous top layer. BET analysis showed that the adsorbent had a low specific surface area. The polymer adsorbent was treated with a sodium hydroxide solution. Both treated and untreated adsorbents were utilised to adsorbate hexavalent chromium from an aqueous solution. The adsorption was carried out under different experimental conditions. Adsorption takes 48 h to reach equilibrium. The intraparticle diffusion mechanism controls adsorption kinetics, while the Langmuir model describes the adsorption isotherm. The treatment of the PVC adsorbent with sodium hydroxide enhances its maximum adsorption capacity from 47.3 mg g⁻¹ to 69.05 mg g⁻¹.

KEYWORDS:

• Polymer adsorbent
• NaOH treatment
• chromium (VI)
• adsorption

Disclosure statement

No potential conflict of interest was reported by the author(s).