The investigation of single ozonation process, catalytic ozonation process and single adsorption on activated carbon efficienciesfor removal of furfural from aqueous solution

Furfural is a toxic chemical، so، to avoid its effects on humans and the environment، furfural-containing wastewater must be treated with an appropriate method prior to dispose in the environment. In this study، advanced oxidation methods based on ozone was used to removal of various concentrations of furfural in laboratory scale. This study is an applied research and the required samples was taken in desired times. The effects of single ozonation process (SOP)، catalytic ozonation process (COP)، and single adsorption on activated carbon (SAP) on furfural removal efficiency in different conditions were studied. In this study، the influence of some important parameters such as pH، activated carbon dosage and reaction time on the efficiency of SOP، SAP and COP was studied. In the case of pH، the results showed that the efficiency of all three processes in very acidic and very alkaline conditions were higher than the other pH. By increasing activated carbon dosages، the removal efficiency was also increased. Finally، the removal efficiency for the processes studied، increased by increasing reaction time. The higher removal efficiency of furfural in acidic conditions can be due to direct and catalytic oxidation of furfural by ozone. Higher efficiency in the alkaline pH may be due to indirect oxidation because of hydroxyl radicals generation. About the effect of reaction time، the removal efficiency of COP indicates that there was a synergistic effect in catalytic ozonation processes. The increase of reaction surfaces available for ozone-activated carbon-furfural reactions could be the reason of increased efficiency with increasing dosages of activated carbon