Novel Submerged Photocatalytic Membrane Reactor for Treatment of Olive Mill Wastewaters

Abstract

A new hybrid photocatalytic membrane reactor that can easily be scaled-up was designed, assembled and used to test photocatalytic membranes developed using the sol-gel technique. Extremely high removals of total suspended solids, chemical oxygen demand, total organic carbon, phenolic and volatile compounds were obtained when the hybrid photocatalytic membrane reactor was used to treat olive mill wastewaters. The submerged photocatalytic membrane reactor proposed and the modified membranes represent a step forward towards the development of new advanced treatment technology able to cope with several water and wastewater contaminants.

Solvent-Free Process for the Development of Photocatalytic Membranes

“…In addition, the membranes produced in this work (without using solvents) proved to have a similar morphology and filtration performance when compared to photocatalytic membranes produced using solvents [19]. Since the photocatalytic membranes produced using solvents proved to be effective to treat wastewaters generated by the olive oil industry [20], the membranes detailed in this work are also expected to be effective to achieve high removals of total suspended solids, chemical oxygen demand, total organic carbon, and phenolic and volatile compounds.…”

“…The savings of ethanol achieved with this new method to produce photocatalytic membranes were calculated. The photocatalytic membrane (produced with ethanol) was already tested with real olive mill wastewaters with extremely promising results [20]. In this work, an average flux of 10 L/(m 2 h) was obtained at 0.2 bar with a membrane with 0.029 m 2 of area.…”

“…Extremely high removals of total suspended solids, chemical oxygen demand, total organic carbon, phenolic and volatile compounds were obtained when these hybrid photocatalytic membranes were tested in a new hybrid photocatalytic membrane reactor to treat olive mill wastewaters [20].…”

Towards a Novel Combined Treatment Approach Using Light-Emitting Diodes and Photocatalytic Ceramic Membranes

“…The only difference in the modification was the deposition method (dip coating was used in this study while drop casting was used in the previous study [17]). Dip coating (previously described by Fraga et al [18]) was the selected method because, if the results of this paper are promising, larger membranes will need to be modified using this technique. The characterization of the membranes used in this study is provided in the Supplementary Material section.…”

“…A hybrid reactor that allows combined treatment using membranes and photocatalysis [18] was recently assembled and tested for the combined treatment of wastewaters, achieving removals of total organic carbon, chemical oxygen demand and phenolic compounds of approximately 90% in the first 20 min of treatment [18]. Even though the submerged photocatalytic membrane reactor and the modified membranes represent a step forward towards the development of new advanced treatment technologies able to cope with several water and wastewater contaminants, it implies the use of large membranes and large photolysis systems (either UV mercury lamps or LED panels) that can irradiate the surface of the membranes.…”