[Application of enzymatic polymerization process for the removal of phenol from synthetic wastewater]

ABSTRACT

Phenolic compounds are presence in many industrial wastewaters, and have been classified as priority pollutants. Application of several conventional processes due to high cost and low efficiency has been limited. Thus, new methods such as enzymatic polymerization seem to be preferable and effective processes with high potential to substitute the conventional processes. This study was carried out to evaluate Raphanus sativus extract as a peroxides enzyme source for polymerization and removal of phenol from synthetic wastewater in the presence of hydrogen peroxide. The study was performed in batch reactor at room temperature. Peroxidase enzyme was extracted from Raphanus sativus plant roots. Primary concentration of phenol in wastewater was 1000 mgl[-1]. The concentration of phenol and enzymatic activity was been measured by photometric assay. The results show that Raphanus sativus extract is a suitable source of peroxidase enzyme. Mean enzymatic activities in this extract was 3.107 Uml[-1]. Also, our results showed that elevation of extract volume lead to high efficiency of phenol removal, in which the increase in the extract volume from 5 to 50 ml, resulted in the efficiency of processes increased from 7.6 to 98.2%. Also, sequencing addition of H2O2 and extract has improved the effects. The phenol removal efficiency of the reaction time after 3 h with single and three stages adding of reactants was 84.2 and 93.1%, respectively. Enzymatic polymerization can be used as an appropriate process for the removal of phenolic compounds from wastewaters. To meet the optimized condition in process, the ratios of phenol/ enzyme and H2O2/ phenol and sequences of the adding of reactants should be considered