INVESTIGATING THE REMOVAL OF METHYL TERTIARY BUTYL ETHER (MTBE) FROM WATER USING RAW AND MODIFIED FLY ASH WASTE MATERIALS

摘要

There are a number of classical remediation techniques that have been tested for the removal of methyl tertiary butyl ether (MTBE) from contaminated water source such as air stripping, adsorption by activated carbon (AC), bio-treatment and chemical oxidation. However, each remediation technique is characterized by inherent limitations due to the special physical and chemical characteristics of this compound, making further researches on MTBE remediation promising. Fly ash (FA), which is a waste material derived from the combustion of coal or heavy liquid fuel has been reported to show favourable results in its application for adsorption of selected heavy metals, dyes and some organics in aqueous solution. In this study, raw FA, acid treated FA and metal oxide (silver, iron and aluminium) impregnated FA were assessed on a bench scale, for their adsorption efficiencies for MTBE treatment in contaminated water system and benchmarked against AC. Results revealed that only silver oxide (Ag_2O) impregnated FA showed about 24% removal of MTBE in aqueous solution, while the other tested adsorbent materials showed less than 10%. MTBE optimum adsorption was attained after 120 min of contact, and 50mg dosage of adsorbent. On the other hand, results showed that silver oxide impregnation of AC brought about a drop in the MTBE removal efficiency of AC from an optimum MTBE removal efficiency of 71% to 53%. Also, the Langmuir isotherm model best represented the MTBE adsorption behaviour of both the Ag_2O impregnated FA and AC, having R2 of 88.75% and 89.92% respectively.