Olive pomace as a low-cost adsorbent for the removal heavy metals

Doil industry waste was investigated. The parameters that affect the heavy metal adsorption such as pH (2-6), contact time (2-120 min.), and initial heavy metal concentrations (5-100 mg/L) were studied in batch experiments at a temperature of 20oC, 0.5 g adsorbent dose and, particle size of between 0.5 and 2.0 mm. The maximum removal efficiencies were obtained 98.8% and 93.2% for Cr(VI) and Cu(II), respectively by using activated olive pomace (AP), at a pH 4, contact time of 15 min. and initial heavy metal concentration of 5 mg/L. The maximum adsorption capacity was determined 0.988 and 0.932 mg/g onto AP for Cr(VI) and Cu(II), respectively. Following this preliminary study, the same optimum conditions were applied to the battery industry wastewater and high removal efficiency was obtained. Moreover, kinetic and isotherm studies were carried out by applying pseudo second order kinetic and Langmuir isotherm model, observing good agreement between theoretical and experimental results at the optimum operation conditions. Various active functional groups were identified by FTIR analysis and SEM images showed that the AP has a porous structure. The study results show that AP has proven its suitability for use in various fields as a low-cost adsorbent in adsorption.