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Emerging Biotechnologies for Treatment of Antibiotic Residues from Pharmaceutical Waste Waters for Sustainable Environment A Case Study under Visible Light with NFC-doped Titania
Published in Gunjan Mukherjee, Sunny Dhiman, Waste Management, 2023
Reyhan Ata, Gökçe Merdan, Gunay Yildiz Tore
In another study conducted by Trovó et al. in 2011, the effect of iron species used in the photo-Fenton process combined with a solar simulator as the energy source on AMX degradation and the toxicity of the intermediates formed in this process was evaluated. It has been found that AMX degradation can be removed more effectively in shorter times (5 minutes with FeOx and 15 minutes with FeSO4) in the presence of potassium ferrioxalate complex (FeOx) compared to the FeSO4 catalyst on the basis of total oxidation. However, the Daphnia Magna toxicity test results indicated the opposite. Test results showed that toxicity decreased from 65 percent to 5 percent after 90 minutes of irradiation using with FeSO4 catalyst, while inhibition ranged from 70 percent to 100 percent using with FeOx catalyst, possibly due to the formation of an oxalate intermediate that is thought to be toxic to newborn daphnia. However, in the process using FeSO4 catalysis, it has been reported that when the reaction time is extended (150 minutes and 240 minutes, respectively), the toxicity, which can be explained as an indicator of the formation of intermediate toxic products, increases to 100% and then decreases to 45% again. In addition, it has been reported that after 240 minutes, TOC can be removed by 73 percent to 81 percent (Trovó et al. 2008, 2011).
Treatment Technologies
Published in Thomas K.G. Mohr, William H. DiGuiseppi, Janet K. Anderson, James W. Hatton, Jeremy Bishop, Barrie Selcoe, William B. Kappleman, Environmental Investigation and Remediation, 2020
William H. DiGuiseppi, James W. Hatton
An improvement to the typical ultraviolet + peroxide system was proposed and tested by Safarzadeh-Amiri et al. (1996), who used an ultraviolet + ferrioxalate + hydrogen peroxide system for treatment of highly contaminated waste streams. The ferrioxalate complex [Fe(C2O4)33−] is widely studied and is used to measure light intensity. The photolysis of ferrioxalate yields ferrous iron, which then reacts with the hydrogen peroxide to generate the hydroxyl radicals and provide a constant source of Fenton's reagent (discussed further in the following section). Safarzadeh-Amiri et al. (1996) demonstrated removal of 1,4-dioxane, among other contaminants, to below unspecified detection limits at substantially higher efficiency than that of ultraviolet + peroxide systems. This greater efficiency would result in fewer ultraviolet bulbs being needed and therefore lower maintenance and energy costs.
Fundamental Aspects
Published in Bruno Langlais, David A. Reckhow, Deborah R. Brink, Ozone in Water Treatment, 2019
Guy Bablon, William D. Bellamy, Marie-Marguerite Bourbigot, F. Bernard Daniel, Marcel Doré, Françoise Erb, Gilbert Gordon, Bruno Langlais, Alain Laplanche, Bernard Legube, Guy Martin, Willy J. Masschelein, Gilbert Pacey, David A. Reckhow, Ciaire Ventresque
Two of the most widely used actinometers for measuring the photon flux of UV lamps are uranyl oxalate UO2C2O4 and potassium ferrioxalate K3Fe (C2O4)3, 3H2O. In the first case, the UV radiation induces the decomposition of the oxalate ions through the following reaction: H2C2O4→hvH2O+CO2+CO
Parameters affecting LED photoreactor efficiency in a heterogeneous photo-Fenton process using iron mining residue as catalyst
Published in Journal of Environmental Science and Health, Part A, 2019
Hernán Dario Rojas-Mantilla, Saidy Cristina Ayala-Durán, Raquel Fernandes Pupo Nogueira
The absorbed photon flux (N) in each LED systems was estimated using potassium ferrioxalate as a chemical actinometer[29] (Eq. 1): where N is the photon flux (Einstein s−1), nFe2+ is the number of moles of Fe2+ generated in the solution after irradiation, Ф is the quantum yield (Φ = 1.21 at 365 nm and 0.92 at 460 nm), and t is the irradiation time (s). The reactor was filled with 300 mL of potassium ferrioxalate solution at concentrations of either 6.0 mmol L−1 (for use of the UV LEDs) or 150 mmol L−1 (for use of the visible light LEDs). Aliquots of 5.0 mL were periodically withdrawn (at times of 1, 2, 4, 6, 8, 10, 12, and 14 min) and transferred to 10.0 mL flasks for the determination of Fe2+. The fluxes of absorbed photons (N) were determined to be 8 × 10−8 and 3 × 10−8 Einstein s−1, using the 21 visible light LEDs and the 5 UV LEDs irradiation sources, respectively (Appendix, Fig. A4).
Analysis of solar and artificial UVA irradiations on the photo-Fenton treatment of phenolic effluent and oilfield produced water
Published in Chemical Engineering Communications, 2018
André Luís Novais Mota, Luiz Gonzaga Lopes Neto, Edson Luiz Foletto, Osvaldo Chiavone-Filho, Cláudio Augusto Oller do Nascimento
Many researchers have studied the application of this kind of process and its variables involved. Studies were performed using ferrioxalate as a source of iron for the degradation of effluents containing benzene toluene ethylbenzene and xylene (BTEX) and phenols (Safarzadeh-Amiri et al., 1997; Monteagudo et al., 2011). Studies on the degradation of organic matter in effluents from the oil industry showed that the photo-Fenton process can be used, especially in the final treatment steps (Mota et al., 2008; Saber et al., 2014; Rubio-Clemente et al., 2015; Silva et al., 2015). Specific works demonstrated the application of this process for the treatment of waters containing diesel oil (Dehghani et al., 2014), acid water from oil refineries (Coelho et al., 2006), and waters contaminated with crude oil (Mater et al., 2007). It is also relevant to notice that studies have been performed on modeling and optimization of photo-oxidation processes (Rozas et al., 2010; Dopar et al., 2011; Ayodele et al., 2012), and on the usage of solar irradiation as energy source (Lucas et al., 2012; Michael et al., 2012; Ahmed and Chiron, 2014). It is well known that the use of a natural source of irradiation like sunlight reduce the costs of AOPs (Turchi et al., 1992; Nascimento et al., 2007; Byrne et al., 2011). However, a quantitative comparison between artificial and natural irradiations is relevant in terms of efficiency. In this way, research works that have addressed a comparison of degradation efficiency among different irradiation sources using a reactor with same geometry and irradiated area are scarce.
Removal of organic matter of electrodialysis reversal brine from a petroleum refinery wastewater reclamation plant by UV and UV/H202 process
Published in Journal of Environmental Science and Health, Part A, 2018
Priscila B. Moser, Bárbara C. Ricci, Clara B. Alvim, Ana C. F. Cerqueira, Míriam C. S. Amaral
All experiments of AOP treatments were conducted in a Pure Pro Ultraviolet Water Sterilizer cylindrical reactor, of 50.5 × 320 mm2 and with 280 mL capacity, with a quartz tube inside. A low-pressure mercury-vapor lamp (6 W) emitting radiation at 254 nm was connected to the quartz tube. The luminous intensity of the mercury-vapor lamp was determined by the potassium ferrioxalate actinometry method, according to Murov.[15] The light intensity determined was 1.03 × 10–6 Einstein min−1.All degradation experiments were conducted at room temperature for 120 min.