Application of Photocatalytic Falling Film Reactor to Elucidate the Degradation Pathways of Pharmaceutical Diclofenac and Ibuprofen in Aqueous Solutions

Diclofenac (DCF) and ibuprofen (IBP) are common pharmaceutical residues that have been detected in the aquatic system. Their presence in the aquatic environment has become an emerging contaminant problem, which has implications for public health. The degradation pathway and identification of transformation products of pharmaceutical residues are crucial to elucidate the environmental fate of photocatalytic decomposition of these pollutants in aqueous media. The degradation process might lead to creation of other possible emerging contaminates. In this study, the degradation of DCF and IBP in aqueous solutions was investigated. To this end, coated TiO2 on a Pilkington Active glass was used as a photocatalyst under UVA illumination, in a planar falling film reactor. Pilkington ActivTM glass was used as a photocatalyst and a falling liquid film generator. Degradation kinetics of both pharmaceuticals followed a pseudo-first-order model. The transformation products of both diclofenac and ibuprofen during the degradation process were detected and identified with gas chromatography–mass spectrometry (GC–MS) and ion chromatography. The results showed that the mineralization rate of both pharmaceuticals through photocatalysis was very low. Low chain carboxylic acids, such as formic, acetic, oxalic, malonic, and succinic acids were the main by-products. A pathway of DCF and IBP degradation was proposed.

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Application of a planar falling film reactor for decomposition and mineralization of methylene blue in the aqueous media via ozonation, Fenton, photocatalysis and non-thermal plasma: A comparative study

Process Safety and Environmental Protection ◽

10.1016/j.psep.2017.11.005 ◽

2018 ◽

Vol 113 ◽

pp. 319-329 ◽

Cited By ~ 26

Author(s):

Kosar Hikmat Hama Aziz ◽

Ali Mahyar ◽

Hans Miessner ◽

Siegfried Mueller ◽

Dieter Kalass ◽

...

Keyword(s):

Methylene Blue ◽

Comparative Study ◽

Thermal Plasma ◽

Aqueous Media ◽

Falling Film ◽

Film Reactor ◽

Non Thermal Plasma

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Gas Chromatography–Mass Spectrometry Quantification of 1,1-Dimethylhydrazine Transformation Products in Aqueous Solutions: Accelerated Water Sample Preparation

Molecules ◽

10.3390/molecules26195743 ◽

2021 ◽

Vol 26 (19) ◽

pp. 5743

Author(s):

Mark S. Popov ◽

Nikolay V. Ul’yanovskii ◽

Dmitry S. Kosyakov

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

Sample Preparation ◽

Aqueous Solutions ◽

Water Sample ◽

Transformation Products ◽

Gas Chromatography Mass Spectrometry ◽

Rocket Fuel ◽

Chromatography Mass Spectrometry ◽

Water Sample Preparation

The use of highly toxic rocket fuel based on 1,1-dimethylhydrazine (UDMH) in many types of carrier rockets poses a threat to environment and human health associated with an ingress of UDMH into wastewater and natural reservoirs and its transformation with the formation of numerous toxic nitrogen-containing products. Their GC-MS quantification in aqueous samples requires matrix change and is challenging due to high polarity of analytes. To overcome this problem, accelerated water sample preparation (AWASP) based on the complete removal of water with anhydrous sodium sulfate and transferring analytes into dichloromethane was used. Twenty-nine UDMH transformation products including both the acyclic and heterocyclic compounds of various classes were chosen as target analytes. AWASP ensured attaining near quantitative extraction of 23 compounds with sample preparation procedure duration of no more than 5 min. Combination of AWASP with gas chromatography–mass spectrometry and using pyridine-d5 as an internal standard allowed for developing the rapid, simple, and low-cost method for simultaneous quantification of UDMH transformation products with detection limits of 1–5 μg L−1 and linear concentration range covering 4 orders of magnitude. The method has been validated and successfully tested in the analysis of aqueous solutions of rocket fuel subjected to oxidation with atmospheric oxygen, as well as pyrolytic gasification in supercritical water modelling wastewater from carrier rockets launch sites.

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Industrial Wastewater Treatment by Photochemical Processes Based on Solar Energy

Journal of Solar Energy Engineering ◽

10.1115/1.2391015 ◽

2005 ◽

Vol 129 (1) ◽

pp. 45-52 ◽

Cited By ~ 14

Author(s):

Claudio A. O. Nascimento ◽

Antonio Carlos S. C. Teixeira ◽

Roberto Guardani ◽

Frank H. Quina ◽

Osvaldo Chiavone-Filho ◽

...

Keyword(s):

Industrial Wastewater ◽

Inorganic Carbon ◽

Degradation Process ◽

Organic Carbon Content ◽

Falling Film ◽

Parabolic Trough ◽

Alternative Source ◽

Chemical Pollutants ◽

Film Reactor ◽

Uv Visible

Background: The solar photo-Fenton process has enormous potential for becoming a viable alternative to conventional processes for the treatment of industrial wastewater. However, the costs associated with the use of artificial irradiation have hindered many times industrial application of these processes. Method of Approach: In this work, the photo-Fenton remediation of various industrial wastewaters (containing silicones, pesticides, phenol and hydrocarbons, model, and real) in aqueous systems has been studied using Fe(II), H2O2, and UV-visible sunlight. Experiments were carried out using a concentrating parabolic trough reactor (PTR) and a nonconcentrating falling-film reactor. Results: In general, at low contaminant concentration, more than 90% of the total organic carbon content could be converted to inorganic carbon within about 2-3h, using sunlight, in reactors of different geometry. Conclusions: Solar light can be used either as an effective complementary or alternative source of photons to the photo-Fenton degradation process of a diversity of chemical pollutants.

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The Electrochemical Degradation of Poly(3,4-ethylenedioxythiophene) Films Electrodeposited from Aqueous Solutions

Zeitschrift für Physikalische Chemie ◽

10.1515/zpch-2016-0752 ◽

2016 ◽

Vol 230 (9) ◽

Cited By ~ 16

Author(s):

Gyözö G. Láng ◽

Mária Ujvári ◽

Soma Vesztergom ◽

Veniamin Kondratiev ◽

Jenö Gubicza ◽

...

Keyword(s):

Aqueous Solutions ◽

Structural Changes ◽

Morphological Changes ◽

Aqueous Media ◽

Degradation Process ◽

Electrochemical Stability ◽

Experimental Techniques ◽

Electrochemical Degradation ◽

Degradation Properties

AbstractIn this review, results of recent studies on the electrochemical stability and degradation properties of poly(3,4-ethylenedioxythiophene) films are summarized, with particular emphasis on the structural changes induced by overoxidation and electrochemical degradation. The most important electrodeposition methods for the preparation of PEDOT films in surfactant free aqueous media have also been summarized, and several experimental techniques suitable for monitoring the degradation process have been discussed. Morphological changes in PEDOT films during overoxidation have been analyzed. Overoxidation mechanisms proposed in the literature have been surveyed.

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Comparative study on 2,4-dichlorophenoxyacetic acid and 2,4-dichlorophenol removal from aqueous solutions via ozonation, photocatalysis and non-thermal plasma using a planar falling film reactor

Journal of Hazardous Materials ◽

10.1016/j.jhazmat.2017.09.025 ◽

2018 ◽

Vol 343 ◽

pp. 107-115 ◽

Cited By ~ 50

Author(s):

Kosar Hikmat Hama Aziz ◽

Hans Miessner ◽

Siegfried Mueller ◽

Ali Mahyar ◽

Dieter Kalass ◽

...

Keyword(s):

Comparative Study ◽

Aqueous Solutions ◽

Thermal Plasma ◽

Dichlorophenoxyacetic Acid ◽

Falling Film ◽

Film Reactor ◽

Non Thermal Plasma ◽

2,4 Dichlorophenoxyacetic Acid

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Application of Silver-Loaded Composite Track-Etched Membranes for Photocatalytic Decomposition of Methylene Blue under Visible Light

Membranes ◽

10.3390/membranes11010060 ◽

2021 ◽

Vol 11 (1) ◽

pp. 60 ◽

Cited By ~ 1

Author(s):

Anastassiya A. Mashentseva ◽

Murat Barsbay ◽

Nurgulim A. Aimanova ◽

Maxim V. Zdorovets

Keyword(s):

Methylene Blue ◽

Visible Light ◽

Degradation Kinetics ◽

Composite Membranes ◽

Degradation Process ◽

Decomposition Reaction ◽

Photocatalytic Decomposition ◽

Order Kinetic ◽

Langmuir Hinshelwood Mechanism ◽

Order Kinetic Model

In this study, the use of composite track-etched membranes (TeMs) based on polyethylene terephthalate (PET) and electrolessly deposited silver microtubes (MTs) for the decomposition of toxic phenothiazine cationic dye, methylene blue (MB), under visible light was investigated. The structure and composition of the composite membranes were elucidated by scanning electron microscopy, energy dispersive spectroscopy, and X-ray diffraction technique. Under visible light irradiation, composite membrane with embedded silver MTs (Ag/PET) displayed high photocatalytic efficiency. The effects of various parameters such as initial dye concentration, temperature, and sample exposure time on the photocatalytic degradation process were studied. The decomposition reaction of MB was found to follow the Langmuir–Hinshelwood mechanism and a pseudo-first-order kinetic model. The degradation kinetics of MB accelerated with increasing temperature and activation energy, Ea, was calculated to be 20.6 kJ/mol. The reusability of the catalyst was also investigated for 11 consecutive runs without any activation and regeneration procedures. The Ag/PET composite performed at high degradation efficiency of over 68% after 11 consecutive uses.

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Study of Photocatalytic Dergradation, Kinetics and Microbial Activities of Copper (ii) Soya Urea Complex in Non Aqueous Media

Letters in Organic Chemistry ◽

10.2174/1570178617999200711175559 ◽

2020 ◽

Vol 17 ◽

Author(s):

Vandana Sukhadia ◽

Rashmi Sharma ◽

Asha Meena

Keyword(s):

Staphylococcus Aureus ◽

Photocatalytic Degradation ◽

Degradation Kinetics ◽

Waste Water Treatment ◽

Aqueous Media ◽

Research Work ◽

Solvent Polarity ◽

Urea Complex ◽

Pseudo First Order Reaction ◽

Aqueous Solvent

Aims: The aim of this research work is to synthesise, study and analyse photocatalytic degradation, kinetics and microbial activity of new surfactant Copper (II) soya urea complex(CSU). Background: Photocatalytic degradation has attracted the attention of scientific community throughout the world due to its multiple applications in environment, energy, waste water treatment, pollution control, green chemistry, etc. Copper (II) soya urea complex has been synthesized and characterized through FT-IR, NMR, ESR studies. Objective: Present work deals with the study of photocatalytic degradation of Copper (II) soya urea complex by using ZnO as semiconductor. This study employs a semiconductor catalyst using non polar and non aqueous solvent in photocatalytic degradation. Reaction rate is chosen as the photocatalytic activity, which has been governed by several factors. Antibacterial activities of Copper (II) complex have also been studied against Staphylococcus aureus. Method: Optical density (O.D.) was measured after different time intervals spectrophotometrically to measure the degradation of complex. Mueller-Hinton agar medium was used for antimicrobial activity of synthesized compound at different concentrations by disk/ well diffusion susceptibility testing. Result: Plot of 2+log O.D. (absorbance) versus time was plotted and found linear. The heterogeneous photocatalysis followed pseudo-first-order reaction kinetics.The present study suggests that Copper (II) soya urea (CSU) complex shows antibacterial activity against Staphylococcus aureus at different concentrations. Conclusion: The results were used to determine the rate of photocatalytic degradation of CSU complex .It has been found that rate of degradation varies with different parameters like concentration of complex, amount of catalyst, light intensity, solvent polarity etc. CSU complex derived from soyabean oil has been shown an inhibitory effect on the growth of S. aureus which may causes skin disease.

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Ouricuri (Syagrus coronata) fiber: a novel biosorbent to remove methylene blue from aqueous solutions

Water Science & Technology ◽

10.2166/wst.2016.495 ◽

2016 ◽

Vol 75 (1) ◽

pp. 106-114 ◽

Cited By ~ 19

Author(s):

Lucas Meili ◽

Társila Santos da Silva ◽

Daniely Carlos Henrique ◽

João Inácio Soletti ◽

Sandra Helena Vieira de Carvalho ◽

...

Keyword(s):

Methylene Blue ◽

Experimental Design ◽

Aqueous Solutions ◽

Adsorption Capacity ◽

Adsorption Process ◽

Fiber Diameter ◽

Aqueous Media ◽

Process Efficiency ◽

Maximum Adsorption Capacity ◽

Equilibrium Studies

In this work, the potential of ouricuri (Syagrus coronata) fiber as a novel biosorbent to remove methylene blue (MB) from aqueous solutions was investigated. The fiber was prepared and characterized according to the fundamental features for adsorption. A 23 experimental design was used to evaluate the effects of adsorbent dosage (M), fiber diameter (D) and agitation (A) on the adsorption capacity. In the more adequate conditions, kinetic and equilibrium studies were performed. The experimental design results showed that M = 10 g L−1), D = 0.595 mm and A = 200 rpm were the more adequate conditions for MB adsorption. Based on the kinetic study, it was found that the adsorption process was fast, being the equilibrium was attained at about 5 min, with 90% of color removal. The isotherm was properly represented by the Sips model, and the maximum adsorption capacity was 31.7 mg g−1. In brief, it was demonstrated that ouricuri fiber is an alternative biosorbent to remove MB from aqueous media, taking into account the process efficiency and economic viewpoint.

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