the evaluation of removal efficiency of phenol from aqueous solutions using moringa peregrina tree shell ash

background and purpose: phenol is one of prevalent contaminants found in many industrial wastewaters. the combination with special features, such as high toxicity, carcinogenic properties, vitality gathering ability, low biodegradation potentiality and others, based on the u.s environmental protection agency, classified as a priority pollutant. the purpose of this study was to determine the efficiency of moringa peregrina tree shell ash for the removal of phenol from aqueous solutions. materials and methods: this study is experimental and pilot scale. to determine the efficiency of moringa peregrina tree shell ash for the removal of phenol from aqueous solutions the examination was carried out in a batch system. to achieve the aim of this study, the effect of each of the parameters affecting the adsorption process, such as initial ph of solution, contact time, adsorbent dose and initial concentration of phenol in solution were studied. results: the results showed that the highest percentage of phenol removal by the ash occurred at ph 6, initial concentration100 mg.l-1and adsorbent dose 0.4 g/l in which the 79.96% phenol was removed. for the analysis of the absorption constant, the freundlich and langmuir isotherm were used. the results showed that the experimental data fit the langmuir (r2=0.9833) much better than the freundlich model (r2=0.9373). conclusion: according to the results of this study, it was found that the moringa peregrina tree shell ash is not only a low-cost adsorbent but also has a high performance in the removal of phenol from aqueous solutions.