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Introduction: Nowadays, application of MTBE due to its physical and chemical characteristics including high solubility in water has been increased, resulting in its release into the water resources. On other hand, waste activated sludge derived from municipal wastewater treatment plant (MWTP) contains high amount of carbon. Therefore, this study aimed to provide the activated carbon via sludge of MWTP as well as to evaluate its efficiency for MTBE removal.

Methods: The effect of some parameters such as kind of activator, pH (2-10), contact time (0-240min), adsorbent dose (2-6g/L) and initial concentration of MTBE (20-70mg/L) was investigated on MTBE adsorption via activated carbon, after preparation of coal from wastewater sludge and activation of this coal via 3 molar solution of H₂PO₄,  and KOH as well as 5 molar solution of ZnCl₂. MTBE concentration in solution was determined via Gas-Chromatography instrument. The obtained experimental data were modeled by adsorption model of Freundlich and Langmuir.

Results: The maximum adsorbed MTBE per gram of activated carbon was obtained when the ZnCL₂ was used as an activator; however, there was no statistically significant difference among different activators. In addition, maximum removal efficiency (about 50%) was obtained in acidic pH of 4, 6g/L of activated carbon and 20mg/L of MTBE concentration. Results of adsorption isotherm showed that Freundlich adsorption model had a better compliance with the experimental data.

Conclusion: Regarding the problems associated with sludge disposal of wastewater treatment plant, recycling of this sludge, as an adsorbent, can eliminate most of these problems. As a result, the economical features with respect to industrial scale application and the efficiency of this substance in removal of other pollutants are recommended to be investigated.