Catalytic ozonation of metolachlor under continuous operation using nanocarbon materials grown on a ceramic monolith

Restivo, João; Órfão, J.J.M.; Armenise, Sabino; García‐Bordejé, Enrique; Pereira, M.F.R.

doi:10.1016/j.jhazmat.2012.08.073

Cited by 48 publications

(22 citation statements)

References 41 publications

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“…These authors verified a slight improvement when ozone was aided by hydrogen peroxide. Restivo et al (2012) tested multiwalled carbon nanotubes as catalyst in the continuous ozonation of metolachlor verifying that the presence of the catalyst and the increase on contact time improved the herbicide mineralisation. Rodríguez et al (2012)) treated urban wastewater spiked with emerging pollutants by continuous ozonation and was able to remove these compounds within the range 67-98 %.…”

Section: Responsible Editor: Bingcai Panmentioning

confidence: 92%

Ozonation and ultrafiltration for the treatment of olive mill wastewaters: effect of key operating conditions and integration schemes

Martins

Ferreira

Gando-Ferreira

et al. 2015

Environ Sci Pollut Res

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With the objective of reaching suitable techniques for olive mill wastewater treatment, ozonation and ultrafiltration were studied individually and combined. A continuous reactor was run for the treatment of a phenolic mixture mimicking an actual olive mill wastewater (OMW) by ozonation. The effect of the main operating parameters was analysed (pH, liquid flow rate and ozone inlet concentration). The increase of pH and ozone dose improved ozonation efficiency. As expected, the highest residence time led to higher steady-state degradation (35 % of chemical oxygen demand (COD) abatement). Even if the rise on ozone inlet gas concentration was able to remove COD in a higher extent, it should be taken into consideration that with the lowest oxidant load (15 g O3/m(3)), the maximum steady-state biochemical oxygen demand (BOD5)/COD ratio was reached which would reduce the process costs. These operating conditions (pH 9, 1 mL/min of liquid flow rate and 15 g O3/m(3)) were applied to an actual OMW leading to 80 % of phenolic content abatement and 12 % of COD removal at the steady state. Regarding ultrafiltration, it was concluded that the best total phenolic content (TPh) and COD abatement results (55 and 15 %) are attained for pH 9 and using a transmembrane pressure drop of 1 bar. Among the integration schemes that were tested, ultrafiltration followed by ozonation was able to reach 93 and 20 % of TPh and COD depletion, respectively. Moreover, this sequence led to an effluent with a BOD5/COD ratio of about 0.55 which means that it likely can be posteriorly refined in a municipal wastewater treatment plant.

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Section: Responsible Editor: Bingcai Panmentioning

confidence: 92%

Ozonation and ultrafiltration for the treatment of olive mill wastewaters: effect of key operating conditions and integration schemes

Martins

Ferreira

Gando-Ferreira

et al. 2015

Environ Sci Pollut Res

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“…1k and m), were placed perpendicularly to each other, irradiating the stream (distance of 5 cm) passing through the loop column, by setting a recirculation flow rate of 60 mL min -1 ( Fig. 1g), as performed in a previous work dealing with catalytic ozonation (Restivo et al, 2012b). The wavelength around 382 nm was chosen considering a compromise between the cost of LEDs (increasing when the emission wavelength decreases) and the possibility to achieve an overlapping between the LEDs main emission wave-length and the TiO2 absorption spectrum.…”

Section: Chemicals and Materialsmentioning

confidence: 99%

“…For this reason, preliminary studies on hydraulic retention time (HRT) were performed using NaCl as tracer (inlet concentration of 2000 mg L -1 ) and uncoated Raschig glass rings were placed randomly inside the loop column, measuring the conductivity with a conductimeter Crison GLP 31 (Barcelona, Spain). The gas and liquid streams were maintained at 15 Ncm 3 min -1 and 15 mL min -1 , having into account preliminary ozonation experiments with different ozone flow rates (using oxalic acid as prove molecule) and that these conditions were optimized for catalytic ozonation in a previous work (Restivo et al, 2012b). The HRT studies allowed to determine the time needed to achieve the steady state and the time spent by the fluid inside the reactor (retention time).…”

Section: Experimental Set-up and Proceduresmentioning

confidence: 99%

Photocatalytic ozonation of urban wastewater and surface water using immobilized TiO2 with LEDs: Micropollutants, antibiotic resistance genes and estrogenic activity

et al. 2016

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Photocatalytic ozonation was employed for the first time in continuous mode with TiO2-coated glass Raschig rings and light emitting diodes (LEDs) to treat urban wastewater as well as surface water collected from the supply area of a drinking water treatment plant (DWTP). Different levels of contamination and types of contaminants were considered in this work, including chemical priority substances (PSs) and contaminants of emerging concern (CECs), as well as potential human opportunistic antibiotic resistant bacteria and their genes (ARB&ARG). Photocatalytic ozonation was more effective than single ozonation (or even than TiO2 catalytic ozonation) in the degradation of typical reaction by-products (such as oxalic acid), and more effective than photocatalysis to remove the parent micropollutants determined in urban wastewater. In fact, only fluoxetine, clarithromycin, erythromycin and 17-alpha-ethinylestradiol (EE2) were detected after photocatalytic ozonation, by using solid-phase extraction (SPE) pre-concentration and LC-MS/MS analysis. In surface water, this treatment allowed the removal of all determined micropollutants to levels below the limit of detection (0.01-0.20 ng L(-1)). The efficiency of this process was then assessed based on the capacity to remove different groups of cultivable microorganisms and housekeeping (16S rRNA) and antibiotic resistance or related genes (intI1, blaTEM, qnrS, sul1). Photocatalytic ozonation was observed to efficiently remove microorganisms and ARGs. Although after storage total heterotrophic and ARB (to ciprofloxacin, gentamicin, meropenem), fungi, and the genes 16S rRNA and intI1, increased to values close to the pre-treatment levels, the ARGs (blaTEM, qnrS and sul1) were reduced to levels below/close to the quantification limit even after 3-days storage of treated surface water or wastewater. Yeast estrogen screen (YES), thiazolyl blue tetrazolium reduction (MTT) and lactate dehydrogenase (LDH) assays were also performed before and after photocatalytic ozonation to evaluate the potential estrogenic activity, the cellular metabolic activity and the cell viability. Compounds with estrogenic effects and significant differences concerning cell viability were not observed in any case. A slight cytotoxicity was only detected for Caco-2 and hCMEC/D3 cell lines after treatment of the urban wastewater, but not for L929 fibroblasts.

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“…CNFs grown on a honeycomb cordierite monolith were also tested in continuous experiments for catalytic ozonation of the herbicide metolachlor. 59 The application of the CNF coated monolith to the continuous ozonation process was shown to have potential, as it improved the TOC removal from 5% to 35%.…”

Section: Carbon Nanostructured Materials On Monolithsmentioning

confidence: 99%

Engineering and Safety Issues

2015

Nanostructured Carbon Materials for Catalysis

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Catalytic ozonation of metolachlor under continuous operation using nanocarbon materials grown on a ceramic monolith

Cited by 48 publications

References 41 publications

Ozonation and ultrafiltration for the treatment of olive mill wastewaters: effect of key operating conditions and integration schemes

Ozonation and ultrafiltration for the treatment of olive mill wastewaters: effect of key operating conditions and integration schemes

Photocatalytic ozonation of urban wastewater and surface water using immobilized TiO2 with LEDs: Micropollutants, antibiotic resistance genes and estrogenic activity

Engineering and Safety Issues

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