Removal of phenolic compounds in olive mill wastewater by silica–alginate–fungi biocomposites

Abstract

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 64.6-88.4 % of phenolic compounds from OMW and OMWS and 91.8-97.5 % in water. Furthermore, in the case of OMW there was also a removal of 30.0-38.1 % of fatty acids, 68.7 % of the sterol and 35 % of COD. The silica-alginate-fungi 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.

Performance and dynamic modeling of a continuously operated pomace olive packed bed for olive mill wastewater treatment and phenol recovery

“…Currently, many researchers use beads with alginate coatings on several kinds of sorbent materials or functionalize them to be more efficient and teste the obtained composites for OMWW PCs or synthetic effluent (Jodra and Mijangos 2007;Kim et al, 2008;Siva Kumar et al, 2009;Duarte et al, 2014). Duarte et al (2014) The objective of this study is to carry out a cycle of olive mill waste treatment in which OP is first converted into a highly porous AC to be used for the treatment of OMWW by adsorption.…”

Degradation of Phenolic Compounds in Palm Oil Mill Effluent by Silica‐Immobilized Bacteria in Internal Loop Airlift Bioreactors

“…Silica alone removed only small amounts of phenolic compounds (Tab. ) because only the adsorption/diffusion phenomena were expected . The degradation efficiency of the silica‐immobilized bacteria varied for different compounds (tested at the same concentrations).…”

Alginate/porous silica matrices for the encapsulation of living organisms: tunable properties for biosensors, modular bioreactors, and bioremediation devices

“…Regarding industrial waste treatment, Duarte et al probed the efficient removal of phenolic compunds of olive oil mill wastewater [20] and organic content from a bleached kraft pulp mill e uent [61] by means of silicaalginate-fungi composites, which were prepared based on our previous development of modular bioremediation devices at a laboratory scale [55]. These treatments take advantage of the natural degrading properties of the strains Rhizopus oryzae, Pleurotus sajor caju and Trametes versicolor to mitigate industrial contaminants such as long chain organic acids, aromatic and fenolic compounds, and the e uent's color, which may be harmful for photosynthetic organisms if released directly to natural watercourses [20,61].…”