Insights into paracetamol degradation in aqueous solutions by ultrasound-assisted heterogeneous electro-Fenton process: Key operating parameters, mineralization and toxicity assessment

The removal of caffeine (CAF) in aqueous solution by peroxymonosulfate oxidant activated with cobalt ion was investigated under a variety of operating conditions. The effects of various operating parameters, such as oxone and Co2+ concentrations, pH value, and the coexistence of dissolved organic matter and inorganic anions on the removal of CAF have been investigated. The removal efficiency increased with the increase in the concentrations of oxone and Co2+ ion added. The additions of chloride, bicarbonate, and sodium humate have negative effects on the removal of CAF. Near-neutral condition (5.0 < pH < 7.0) is favorable for the removal of CAF. Based on our experiments, 100% degradation of 50 mg/L CAF can be achieved within 4 minutes under the conditions of 1.00 mM oxone and 0.10 mM Co2+ ion at pH 5.0–7.0.

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Treatment of swine wastewater using the Fenton process with ultrasound and recycled iron

Ambiente e Agua - An Interdisciplinary Journal of Applied Science ◽

10.4136/ambi-agua.2453 ◽

2020 ◽

Vol 15 (3) ◽

pp. 1

Author(s):

Jair Juarez João ◽

Cíntia Souza da Silva ◽

José Luiz Vieira ◽

Milena Felipe da Silveira

Keyword(s):

Hydrogen Peroxide ◽

Biological Systems ◽

Oxygen Demand ◽

Swine Wastewater ◽

Organic Load ◽

Fenton Process ◽

Slaughterhouse Wastewater ◽

Pork Production ◽

Biological Sludge ◽

Ultrasound Assisted

Pork production involves the generation of wastewater containing a high pollutant load. Although the biological systems show satisfactory efficiency for the treatment of these effluents, they demand an elevated area for installation and high production of biological sludge. Alternatively, oxidative processes are an alternative for treating such effluents, requiring minor areas and increasing the efficiency of the treatment. We studied the Fenton process assisted with ultrasound for the treatment of swine slaughterhouse wastewater. Nails used in civil construction were used as the iron source. We evaluated the influence of pH, contact time, nail mass, and hydrogen peroxide concentration on color removal, turbidity, chemical oxygen demand (COD) and biochemical oxygen demand (BOD5). The removal of nutrients and oils and greases was also evaluated. The best results using the ultrasound-assisted Fenton process were obtained at pH 3, hydrogen peroxide concentration 90 mg L-1, and a nail unit (2.7g). In these conditions, color, turbidity, COD, and BOD5 removal of 98, 98.2, 84.6, and 98%, respectively, were achieved. The reduction in the other parameters evaluated was above 70%. Catalytic activity maintained above 90% until the sixth cycle of use. In general, the ultrasound-assisted Fenton process using the nail as a catalyst would be an alternative for the treatment of swine slaughterhouse wastewater. This alternative is responsible for the higher removal of organic load and nutrients in a shorter time when compared with biological systems.

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Optimization of ibuprofen degradation in water using high frequency ultrasound-assisted biological reactor

Water Science & Technology ◽

10.2166/wst.2020.291 ◽

2020 ◽

Vol 81 (10) ◽

pp. 2250-2259

Author(s):

Arwa Abdelhay ◽

Aya Allafi ◽

Abeer Albsoul

Keyword(s):

Power Density ◽

Advanced Oxidation Process ◽

Oxygen Demand ◽

Pharmaceutical Product ◽

Degradation Efficiency ◽

Operating Parameters ◽

Sonication Time ◽

High Frequency Ultrasound ◽

Working Volume ◽

Ultrasound Assisted

Abstract Ultrasound (US) is being considered as a promising emerging advanced oxidation process to degrade persistent organic-pollutants. This paper investigated the effect of several operating parameters on the degradation of a recalcitrant pharmaceutical product, namely ibuprofen (IBP), using an ultrasound-assisted biological reactor. The tested operating parameters are the power density (960, 480) W/L, US frequency (1,142, 860, 578) kHz, working volume (500, 250) mL, initial IBP concentration (30, 60) mg/L, and pH (8.2, 4). It was observed that the IBP degradation was directly influenced by the power density, and the highest degradation efficiency (99%) was obtained at 960 w/L. However, the degradation of IBP at sonication time of 120 min was found to increase from 39% to 96% while decreasing the US frequency from 1,142 to 578 kHz. The working volume had no clear effect on the IBP degradation. The optimal pH was found to be 4, which resulted in 99.5% IBP degradation efficiency after 120 min of sonication time. The degradation of IBP followed the first order kinetics. Finally, the sonically-treated water was fed to a subsequent aerobic biological reactor. The results revealed that the remaining chemical oxygen demand (COD) after sonication was lowered in the biological reactor by a percentage of 47%.

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Modified bentonite for anionic dye removal from aqueous solutions. Adsorbent regeneration by the photo-Fenton process

Comptes Rendus Chimie ◽

10.1016/j.crci.2018.12.001 ◽

2019 ◽

Vol 22 (2-3) ◽

pp. 154-160 ◽

Cited By ~ 4

Author(s):

Selma Khelifi ◽

Fadhila Ayari

Keyword(s):

Aqueous Solutions ◽

Dye Removal ◽

Fenton Process ◽

Modified Bentonite ◽

Anionic Dye ◽

Adsorbent Regeneration

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Intensified-Fenton process for the treatment of phenol aqueous solutions

Water Science & Technology ◽

10.2166/wst.2014.515 ◽

2014 ◽

Vol 71 (3) ◽

pp. 359-365 ◽

Cited By ~ 6

Author(s):

M. Isabel Pariente ◽

Raúl Molina ◽

Juan Antonio Melero ◽

Juan Ángel Botas ◽

Fernando Martínez

Keyword(s):

Hydrogen Peroxide ◽

Aqueous Solutions ◽

Heterogeneous Catalyst ◽

Reaction Temperature ◽

Catalytic Performance ◽

Fenton Process ◽

Iron Species ◽

Iron Extraction ◽

Dissolved Iron ◽

Iron Leaching

An intensified-Fenton process for the treatment of phenol aqueous solutions has been studied as a continuous catalytic wet hydrogen peroxide oxidation system. This process consists of coupling the catalytic activity of a heterogeneous Fenton-like catalyst with the homogeneous contribution of its dissolved iron species. Agglomerated mesoporous SBA-15 silica-supported iron oxide (Fe2O3/SBA-15) material was used as heterogeneous catalyst. The influence of the reaction temperature and the initial hydrogen peroxide dosages was studied in order to minimize the operation cost of the process. The catalytic performance of the process was assessed in terms of total organic carbon (TOC) and hydrogen peroxide conversions. Likewise, the stability of the solid Fenton-like catalyst was also evaluated in terms of the dissolved iron species. The increase of the reaction temperature enhanced the TOC conversion and reduced the iron leaching from the heterogeneous catalyst. These results were related to the degradation of oxalic acid as responsible for iron extraction by formation of soluble stable iron complexes into the aqueous medium. Finally, the use of a moderate hydrogen peroxide concentration (2.6 g/L) and milder temperatures (80–120 °C) has led to remarkable results of TOC and phenol reductions as well as oxidant efficiency through the intensified-Fenton process.

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Simultaneous ultrasonic-assisted removal of malachite green and safranin O by copper nanowires loaded on activated carbon: central composite design optimization

RSC Advances ◽

10.1039/c5ra03519h ◽

2015 ◽

Vol 5 (70) ◽

pp. 57021-57029 ◽

Cited By ~ 49

Author(s):

Mostafa Roosta ◽

Mehrorang Ghaedi ◽

Arash Asfaram

Keyword(s):

Activated Carbon ◽

Aqueous Solutions ◽

Central Composite Design ◽

Design Optimization ◽

Malachite Green ◽

Copper Nanowires ◽

Ultrasonic Assisted ◽

Ultrasound Assisted ◽

Safranin O ◽

Central Composite

The present study investigates the simultaneous ultrasound-assisted adsorption of malachite green (MG) and safranin O (SO) dyes from aqueous solutions by ultrasound-assisted adsorption onto copper nanowires loaded on activated carbon (Cu-NWs-AC).

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