Synthesis and adsorption properties of activated carbon from KOH-activation of Moroccan Jujube shells for the removal of COD and color from wastewater

Abstract

This study aimed to investigate the applicability of new low-cost activated carbons with a high surface area prepared by KOH chemical activation of jujube shells (denoted JSAC) as adsorbent of Chemical Organic Demand (COD) from wastewater. The prepared activated carbon is characterized by various physical-chemical methods to determine their morphological, textural and chemical characterization, including nitrogen adsorption-desorption isotherms, Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), Boehm titration method and the pH of the point of zero charge (pHPZC). Then they were used as an adsorbent for the removal of COD from wastewater collected from Fez area. Adsorption equilibrium and kinetic data were determined and fitted to several adsorption isotherms and kinetics models, respectively. The results showed that the Langmuir isotherm fitted well the equilibrium data of COD on JSAC adsorbent; whereas, the kinetic data were best fitted by the pseudo-second-order model. This adsorbent showed the highest removal efficiency for COD (72%) and the grey colour of the wastewater (83%) for an optimum dose of 0.5 gJSAC. L-1. Results from the study showed that JSAC activated carbon could be utilized as an effective and less expensive adsorbent for the removal of COD in wastewater.