20 research outputs found
Removal of phenolic compounds in olive mill wastewater by silica-alginate-fungi biocomposites
This study aims to attempt a treatment strategy
based on fungi immobilized on silica-alginate (biocomposites)
for removal of phenolic compounds in olive oil
mill wastewater (OMW), OMW supplemented (OMWS)
with phenolic compounds and water supplemented (WS)
with phenolic compounds, thus decreasing its potential
impact in the receiving waters. Active (alive) or inactive
(death by sterilization) Pleurotus sajor caju was encapsulated
in alginate beads. Five beads containing active and
inactive fungus were placed in a mold and filled with silica
hydrogel (biocomposites). The biocomposites were added
to batch reactors containing the OMW, OMWS and WS.
The treatment of OMW, OMWS and WS by active and
inactive biocomposites was performed throughout 28 days
at 25 C. The efficiency of treatment was evaluated by
measuring the removal of targeted organic compounds,
chemical oxygen demand (COD) and relative absorbance
ratio along the time. Active P. sajor caju biocomposites
were able to remove 64.6â88.4 % of phenolic compounds
from OMW and OMWS and 91.8â97.5 % in water. Furthermore,
in the case of OMW there was also a removal of
30.0â38.1 % of fatty acids, 68.7 % of the sterol and 35 %
of COD. The silicaâalginateâfungi biocomposites showed
a high removal of phenolic compounds from OMW and
water. Furthermore, in the application of biocomposites to
the treatment of OMW it was observed also a decrease on
the concentration of fatty acids and sterols as well as a
reduction on the COD
Sequential treatment of olive oil mill wastewater with adsorption and biological and photo-Fenton oxidation
WOS: 000318175400033PubMed: 23054778Olive oil mill wastewater (OMWW), a recalcitrant pollutant, has features including high phenolic content and dark color; thereby, several chemical or physical treatments or biological processes were not able to remediate it. In this study, the treatment efficiencies of three treatments, including adsorption, biological application, and photo-Fenton oxidation were sequentially evaluated for OMWW. Adsorption, biological treatment, and photo-Fenton caused decreasing phenolic contents of 48.69 %, 59.40 %, and 95 %, respectively. However, after three sequential treatments were performed, higher reduction percentages in phenolic (total 99 %) and organic contents (90 %) were observed. Although the studied fungus has not induced significant color reduction, photo-Fenton oxidation was considered to be an attractive solution, especially for color reduction. Besides, toxicity of OMWW treatment was significantly reduced