Removal of methyl tertiary-butyl ether (MTBE) from water by polymer–zeolite composites

Methyl tertiary-butyl ether (MTBE), a semi volatile organic compound used as a gasoline additive, has been extensively detected in surface and groundwater and therefore became a major issue as an environmental pollutant. The removal of methyl tertiary-butyl ether (MTBE) from water by high-silica zeolite, high-silica zeolite composites, and by granular activated carbon (GAC) was investigated in suspension and by filtration. The Langmuir model yielded good simulation and prediction of MTBE removal. The removal of MTBE from water was more efficient by composites of polyacrylamide (PAM)-zeolite designed in this study than by untreated zeolite or GAC. Even in the presence of BTEX (benzene, toluene, ethyl-benzene and xylene) MTBE removal was very efficient by the PAM-zeolite composites, in comparison to its removal by the zeolite or GAC, reaching 2.5- and 75-fold higher removal, respectively. Filtration of MTBE solution through columns filled with GAC mixed with a PAM-zeolite composite (5:1 w/w ratio) demonstrated several-fold enhanced removal relative to a control which included only GAC. We suggest that the enhanced removal by the PAM-zeolite composite is attributed to (a) the displacement of water from the zeolite surface upon PAM adsorption, which promotes MTBE adsorption and (b) hydrogen binding between the polymer and MTBE.

MTBE (in red) adsorbed on granular activated carbon (in black), silicalite zeolite (in blue) and composite of PAM polymer (in green) adsorbed on silicalite zeolite.Figure optionsDownload as PowerPoint slideHighlights
► Methyl tertiary-butyl ether (MTBE) has been extensively used as a gasoline additive.
► Its occurrence in drinking water resources has become a major issue.
► This study demonstrates efficient removal of MTBE from water by polyacrylamide-high-silica zeolite composite.
► Efficient removal of MTBE was also achieved in the presence of BTEX (benzene, toluene, ethyl-benzene and xylene).