Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 63
Filter
1.
J Environ Sci (China) ; 145: 216-231, 2024 Nov.
Article in English | MEDLINE | ID: mdl-38844321

ABSTRACT

Catalytic ozonation is an effective wastewater purification process. However, the low ozone mass transfer in packed bubble columns leads to low ozone utilization efficiency (OUE), poor organic degradation performance, and high energy consumption. Therefore, there is an urgent need to develop efficient supported catalysts that can enhance mass transfer and performance. However, the reaction mechanism of the support on ozone mass transfer remains unclear, which hinders the development of catalytic ozonation applications. In this study, lava rocks (LR)-supported catalysts, specifically CuMn2O4@LR and MnO2Co3O4@LR, were proposed for catalytic ozonation of IBP degradation due to their superior catalytic activity, stability, and high OUE. Addition of CuMn2O4@LR or MnO2Co3O4@LR increased IBP removal efficiency from 85% to 91% or 88%, and reduced energy consumption from 2.86 to 2.14 kWh/m3 or 2.60 kWh/m3, respectively. This improvement was attributed to LR-supported catalysts enhancing mass transfer and promoting O3 decomposition to generate •OH and •O2-, leading to IBP degradation. Furthermore, this study investigated the effects of ozone dose, supporter sizes, and catalyst components on ozone-liquid mass transfer. The results revealed that the size of the supporter influenced stacked porosity and consequently affected ozone mass transfer. Larger-sized LR (kLa= 0.172 min-1) exhibited better mass transfer compared to smaller-sized supports. Based on these findings, it was concluded that both CuMn2O4@LR and MnO2Co3O4@LR are potential catalysts for catalytic ozonation in residual IBP degradation of pharmaceutical wastewater, and LR showed good credibility as a catalyst supporter. Understanding the effects of supporters and active components on ozone mass transfer provides a fundamental principle for designing supported catalysts in catalytic ozonation applications.


Subject(s)
Ibuprofen , Ozone , Waste Disposal, Fluid , Water Pollutants, Chemical , Ozone/chemistry , Catalysis , Water Pollutants, Chemical/chemistry , Ibuprofen/chemistry , Waste Disposal, Fluid/methods , Wastewater/chemistry , Water Purification/methods
2.
J Environ Sci (China) ; 115: 88-102, 2022 May.
Article in English | MEDLINE | ID: mdl-34969480

ABSTRACT

In this study, carbamazepine (CBZ) decay in solution has been studied by coupling electrocoagulation with electro-Fenton (EC-EF) with a novel P-rGO/carbon felt (CF) cathode, aiming to accelerate the in-situ generation of •OH, instead of adding Fe2+ and H2O2. Firstly, the fabricated P-rGO and its derived cathode were characterized by XRD, SEM, AFM, XPS and electrochemical test (EIS, CV and LSV). Secondly, it was confirmed that the performance in removal efficiency and electric energy consumption (EEC) by EC-EF (kobs=0.124 min-1, EEC=43.98 kWh/kg CBZ) was better than EF (kobs=0.069 min-1, EEC=61.04 kWh/kg CBZ). Then, P-rGO/CF (kobs=0.248 min-1, EEC=29.47 kWh/kg CBZ, CE=61.04%) showed the best performance in EC-EF, among all studied heteroatom-doped graphene/CF. This superior performance may be associated with its largest layer spacing and richest C=C, which can promote the electron transfer rate and conductivity of the cathode. Thus, more H2O2 and •OH could be produced to degrade CBZ, and almost 100% CBZ was removed with kobs being 0.337 min-1 and the EEC was only 24.18 kWh/kg CBZ, under the optimal conditions (P-rGO loading was 6.0 mg/cm2, the current density was 10.0 mA/cm2, the gap between electrode was 2.0 cm). Additionally, no matter the influent is acidic, neutral or alkaline, no additional pH adjustment is required for the effluent of EC-EF. At last, an inconsecutive empirical kinetic model was firstly established to predict the effect of operating parameters on CBZ removal.


Subject(s)
Hydrogen Peroxide , Water Pollutants, Chemical , Carbamazepine , Electrocoagulation , Electrodes , Graphite , Oxidation-Reduction , Water Pollutants, Chemical/analysis
3.
Molecules ; 26(22)2021 Nov 18.
Article in English | MEDLINE | ID: mdl-34834057

ABSTRACT

Phthalic acid esters (PAEs) have a negative impact on living organisms in the environment, therefore, are among the group of Endocrine Disrupting Compounds (ECDs). Unfortunately, conventional methods used in municipal wastewater treatment plants (MWWTPs) are not designed to eliminate PAEs. For this reason, the development of cheap and simple but very effective techniques for the removal of such residues from wastewater is crucial. The main aim of this study was the evaluation of the removal of six selected PAEs: diethyl phthalate (DEP), di-n-octyl phthalate (DOP), di-n-butyl phthalate (DBP), benzyl butyl phthalate (BBP), bis(2-ethylhexyl) phthalate (DEHP) and dimethyl phthalate (DMP), in real MWWTPs supported by constructed wetlands (MWWTP-CW system). For the first time, the possibility of using three new plants for this purpose, Cyperus papyrus (papyrus), Lysimachia nemorum (yellow pimpernel) and Euonymus europaeus (European spindle), has been presented. For determining the target PAEs in wastewater samples, a method of SPE (Solid-Phase Extraction)-GC-MS(SIM) was developed and validated, and for plant materials, a method of UAE (Ultrasound-Assisted Extraction)-SPE-GC-MS(SIM) was proposed. The obtained data showed that the application of the MWWTP-CW system allows a significant increase in the removal of DEP, DBP, BBP and DEHP from the wastewater stream. Euonymus europaeus was the most effective among the tested plant species for the uptake of analytes (8938 ng × g-1 dry weight), thus, this plant was found to be optimal for supporting conventional MWWTPs.


Subject(s)
Phthalic Acids/isolation & purification , Water Pollutants, Chemical/isolation & purification , Water Purification/methods , Esters/isolation & purification
4.
Molecules ; 25(12)2020 Jun 26.
Article in English | MEDLINE | ID: mdl-32604747

ABSTRACT

Pharmaceuticals, due to their pseudo-persistence and biological activity as well as their extensive use in human and veterinary medicine, are a class of environmental contaminants that is of emerging concern [...].


Subject(s)
Environmental Monitoring/methods , Pharmaceutical Preparations/analysis , Wastewater/analysis , Animals , Biodegradation, Environmental , Humans , Pharmaceutical Preparations/isolation & purification , Water Purification
5.
Molecules ; 25(22)2020 Nov 20.
Article in English | MEDLINE | ID: mdl-33233593

ABSTRACT

Some of the most common microtraces that are currently collected at crime scenes are fragments of single fibers. The perpetrator leaves them at a crime scene or takes them away, for example, on their clothing or body. In turn, the microscopic dimensions of such traces mean that the perpetrator does not notice them and therefore usually does not take action to remove them. Cotton and polyester fibers dyed by reactive and dispersion dyes, respectively, are very popular within clothing products, and they are hidden among microtraces at the scene of a crime. In our recently published review paper, we summarized the possibilities for the identification of disperse dyes of polyester fibers for forensic purposes. In this review, we are concerned with cotton fibers dyed with reactive dyes. Cotton fibers are natural ones that cannot easily be distinguished on the basis of morphological features. Consequently, their color and consequently the dye composition are often their only characteristics. The presented methods for the identification of reactive dyes could be very interesting not only for forensic laboratories, but also for scientists working in food, cosmetics or pharmaceutical/medical sciences.


Subject(s)
Coloring Agents/chemistry , Cotton Fiber/analysis , Forensic Medicine , Forensic Medicine/methods , Humans , Molecular Structure , Spectrum Analysis , Textiles
6.
Molecules ; 25(12)2020 Jun 20.
Article in English | MEDLINE | ID: mdl-32575673

ABSTRACT

Antibiotic resistance is a growing problem worldwide. The emergence and rapid spread of antibiotic resistance determinants have led to an increasing concern about the potential environmental and public health endangering. Wastewater treatment plants (WWTPs) play an important role in this phenomenon since antibacterial drugs introduced into wastewater can exert a selection pressure on antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs). Therefore, WWTPs are perceived as the main sources of antibiotics, ARB and ARG spread in various environmental components. Furthermore, technological processes used in WWTPs and its exploitation conditions may influence the effectiveness of antibiotic resistance determinants' elimination. The main aim of the present study was to compare the occurrence of selected tetracycline and sulfonamide resistance genes in raw influent and final effluent samples from two WWTPs different in terms of size and applied biological wastewater treatment processes (conventional activated sludge (AS)-based and combining a conventional AS-based method with constructed wetlands (CWs)). All 13 selected ARGs were detected in raw influent and final effluent samples from both WWTPs. Significant ARG enrichment, especially for tet(B, K, L, O) and sulIII genes, was observed in conventional WWTP. The obtained data did not show a clear trend in seasonal fluctuations in the abundance of selected resistance genes in wastewaters.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacteria/genetics , Drug Resistance, Microbial/genetics , Genes, Bacterial/genetics , Plants/genetics , Waste Disposal, Fluid/methods , Wastewater/analysis , Water Purification/methods , Bacteria/drug effects , Genes, Bacterial/drug effects , Plants/drug effects , Poland , Sewage/analysis , Sulfonamides/pharmacology , Tetracycline/pharmacology , Wetlands
7.
Ecotoxicol Environ Saf ; 181: 499-507, 2019 Oct 15.
Article in English | MEDLINE | ID: mdl-31229840

ABSTRACT

In recent years, increasing eutrophication in large freshwater lakes, which are an important drinking water source for cities in China, have been resulted in substantial cyanobacteria blooms that could cause serious taste and odor (T&O) problems. In this investigation, three typical lakes (Songhua Lake, Chaohu Lake and Taihu Lake) as drinking water sources located in different geographical areas in China, were selected to study the problems of cyanobacteria-derived T&O (i.e., 2-methylisobornoel, geosmin, ß-ionone, 2-isopropyl-3-methoxypyrazine, 2-isobutyl-3-methoxypyrazine, and 2-methylbenzofuran). The occurrence of T&O in target lakes was compared across various nutrition states and geographic locations, to get more information for early warning for algal bloom and T&O occurrence, being useful lake water management and purification. Results show that the occurrence of T&O in Songhua Lake was the poorest for the lowest nutrient state, as a first report in T&O research field in China. This is a lake located in Northeast China at high latitude, with lower water temperatures. The occurrence of T&O in Chaohu Lake was ranked in the middle. That in Taihu Lake was the most intensive. Finally, the relationship between water quality, T&O and its origin was analyzed by multivariate statistical methods (correlation analysis, principal component, and cluster analyses).


Subject(s)
Cyanobacteria/metabolism , Lakes/microbiology , Odorants/analysis , Taste , China , Environmental Monitoring , Eutrophication , Lakes/chemistry , Nutrients/analysis , Nutrients/standards , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/standards , Water Quality
8.
Molecules ; 25(1)2019 Dec 31.
Article in English | MEDLINE | ID: mdl-31906110

ABSTRACT

The problem of the presence of pharmaceuticals and endocrine disrupting compounds (EDCs) in the environment is closely related to municipal wastewater and in consequence to municipal wastewater treatment plants (MWWTPs) because wastewater is the main way in which these compounds are transferred to the ecosystem. For this reason, the development of cheap, simple but very effective techniques for the removal of such residues from wastewater is very important. In this study, the analysis of the potential of using three new plants: Cyperus papyrus (Papyrus), Lysimachia nemorum (Yellow pimpernel), and Euonymus europaeus (European spindle) by hydroponic cultivation for the removal of 15 selected pharmaceuticals and endocrine disrupting compounds (EDCs) in an MWWTP is presented. In order to obtain the most reliable data, this study was performed using real WWTP conditions and with the determination of the selected analytes in untreated sewage, treated sewage, and in plant materials. For determining the target compounds in plant materials, an Accelerated Solvent Extraction (ASE)-Solid-Phase Extraction (SPE)-GC-MS(SIM) method was developed and validated. The obtained data proved that the elimination efficiency of the investigated substances from wastewater was in the range of 35.8% for diflunisal to above 99.9% for paracetamol, terbutaline, and flurbiprofen. Lysimachia nemorum was the most effective for the uptake of target compounds among the tested plant species. Thus, the application of constructed wetlands for supporting conventional MWWTPs allowed a significant increase in their removal from the wastewater stream.


Subject(s)
Endocrine Disruptors/analysis , Hydroponics , Pharmaceutical Preparations/analysis , Sewage/chemistry , Waste Disposal, Fluid/methods , Water Pollutants, Chemical/analysis , Cyperus/chemistry , Cyperus/metabolism , Ecosystem , Euonymus/chemistry , Euonymus/metabolism , Gas Chromatography-Mass Spectrometry , Primulaceae/chemistry , Primulaceae/metabolism , Sewage/analysis , Solid Phase Extraction/methods , Wetlands
9.
Molecules ; 24(3)2019 Feb 10.
Article in English | MEDLINE | ID: mdl-30744148

ABSTRACT

In forensic laboratories, the most commonly analyzed microtraces are microscopic fragments of single fibers. One of the main goals of the examination of fragments of fibers a few millimeters long is to determine their characteristic physicochemical properties and compare them with fibers originating from a known source (e.g., a suspect's clothes). The color and dyes of fiber microtraces play an important role in their research and evaluation, being analyzed by means of microscopic, spectroscopic, and chromatographic methods. The results of examinations conducted with the use of spectroscopic techniques might be ambiguous due to overlapping bands of absorption and the transmission and dispersion of electromagnetic radiation corresponding to the specific chemical structure of the fibers and their dyes. For this reason, it is very important to improve currently available spectroscopic methods and/or to propose new ones that allow evidential materials to be analyzed in a much more reliable way. In this review, the possibility of the use of chromatographic techniques with different detection systems for such analyses is underlined. This review covers the different analytical methods used in the forensic analysis of polyester fibers dyed with disperse dyes. Polyester fibers occupy the first position among synthetic fibers in their use for a variety of purposes, and disperse dyes are commonly applied for dyeing them.


Subject(s)
Coloring Agents/chemistry , Forensic Medicine , Polyesters/chemistry , Textiles/analysis , Forensic Medicine/methods , Solvents/chemistry , Spectrum Analysis
10.
Anal Bioanal Chem ; 410(6): 1697-1707, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29350257

ABSTRACT

The widespread use of tetracyclines (TCs) in animal husbandry is associated with their constant penetration into the environment and the threat they might pose to living organisms. While the literature data on the analysis of these substances in such matrices as food, tissues, or wastewater are quite extensive, there are still only a few methods presented for the determination of these compounds in soil samples. Moreover, among the literature methods for the extraction of TCs from soil samples, microwave-assisted solvent extraction (MAE) was used only once and in combination with liquid chromatography with spectrophotometric detection (LC-UV). However, according to the EU Commission Decision 2002/657/EC, the use of LC-UV for the determination of compounds, including pharmaceuticals, in environmental samples is not sufficient. Therefore, the development and application of a sensitive and selective method using the MAE-SPE-LC-MS/MS(MRM) technique for the isolation and identification of a mixture of oxytetracycline (OTC), tetracycline (TC), and chlortetracycline (CTC) in soils is presented in our study. The credibility of this method has been confirmed with good parameters of validation. The optimal extraction conditions of three TCs using MAE techniques were to conduct double extraction for 10 min each, at 60 °C, using a mixture of ACN:McIlvaine buffer:0.1 M EDTA (2:1:1, v/v/v) and an additional cleaning of the extracts by SPE. The effectiveness of the extraction of these compounds was assessed based on two different ways (absolute recovery from 46 to 65.1% and relative recovery from 101.1 to 109.5%). Finally, the validated MAE-SPE-LC-MS/MS(MRM) method was used for the analysis of six samples from agricultural areas of northern Poland. OTC and TC, at concentrations of 11.7 and 14.5 µg kg-1 were determined in two different samples. An assessment of risk quotients was also performed. The presented method was proven to be a useful tool in the analysis of residues of selected TCs in the soil ecosystem. Obtained data on the presence of these drugs in Polish soils is the first report for this country.

11.
Rev Environ Contam Toxicol ; 243: 89-148, 2017.
Article in English | MEDLINE | ID: mdl-28005213

ABSTRACT

The use of veterinary pharmaceuticals (VPs) is a result of growing animal production. Manure, a great crop fertilizer, contains a significant amount of VPs. The investigation of VPs in manure is prevalent, because of the potential risk for environmental organisms, as well as human health. A re-evaluation of the impact of veterinary pharmaceuticals on the agricultural environment is needed, even though several publications appear every year. The aim of this review was to collate the data from fields investigated for the presence of VPs as an inevitable component of manure. Data on VP concentrations in manure, soils, groundwater and plants were collected from the literature. All of this was connected with biotic and abiotic degradation, leaching and plant uptake. The data showed that the sorption of VPs into soil particles is a process which decreases the negative impact of VPs on the microbial community, the pollution of groundwater, and plant uptake. What was evident was that most of the data came from experiments conducted under conditions different from those in the environment, resulting in an overestimation of data (especially in the case of leaching). The general conclusion is that the application of manure on crop fields leads to a negligible risk for plants, bacteria, and finally humans, but in future every group of compounds needs to be investigated separately, because of the high divergence of properties.


Subject(s)
Agriculture , Pharmaceutical Preparations/analysis , Soil Pollutants/toxicity , Veterinary Medicine , Water Pollutants, Chemical/toxicity , Soil Pollutants/analysis , Water Pollutants, Chemical/analysis
12.
J Hazard Mater ; 477: 135343, 2024 Sep 15.
Article in English | MEDLINE | ID: mdl-39068888

ABSTRACT

Iron-based biochar exhibits great potential in degrading emerging pollutants and remediation of water environments. In this study, a highly efficient catalytic Fe0/biochar (MZB-800) was synthesized by the co-pyrolysis of poplar sawdust and K2FeO4 at 800 °C. A novel water purification technology of pre-reduction followed by PMS activation for MZB-800 was proposed to degrade the refractory 2,4-dichlorophenoxyacetic acid (2,4-D) pesticide. The corrosive effect of the strong oxidizing potassium salt endowed the MZB-800 surface with more Fe0 and porous structure, achieving greater 2,4-D adsorption binding energy. The removal efficiency of MZB-800 on 2,4-D was greater than that of biochar (BC) and conventional Fe0/biochar (Fe-BC) prepared by FeCl3·6 H2O as the precursor. The proposed novel water purification technology showed the synergistic effect between the interfacial pre-reduction and the PMS activation derived by MZB-800. Regarding 2,4-D degradation and dechlorination performance, the synergistic coefficient between pre-reduction and subsequent PMS activation for MZB-800 were 2 and 1.4 respectively. Based on the normalized kinetic analysis and the Langmuir-Hinshelwood model, we proposed the underlying mechanism of MZB-800 interfacial pre-reduction and subsequent PMS activation for synergistic removal of 2,4-D. The large amount of Fe2+ and hydroxyl density accumulated by the Fe0 and hydroquinone structures on the MZB-800 surface during the pre-reduction stage provided abundant active sites for the subsequent activation of PMS. The improved activation reaction rate generated more reactive oxygen species, further strengthening the removal efficiency of 2,4-D. This work manifested that the novel water purification technology of pre-reduction/PMS activation of iron-based biochar is feasible for removing emerging pollutants in the water environment. ENVIRONMENTAL IMPLICATION: Extensive abuse of 2,4-dichlorophenoxyacetic acid (2,4-D) herbicide with high solubility and refractory degradation has caused environmental pollution and ecological deterioration. This manuscript described a novel water purification technology, centered on high-efficiency Fe0/biochar and utilizing pre-reduction and PMS reactivation strategies to synergistically degrade 2,4-D, which had strong environmental relevance. By elucidating the synergistic removal mechanism, the research provided valuable insights into removing emerging pollutants, thus promoting environmental sustainability and safeguarding ecosystem health. Overall, it is of high importance to provide a feasible and efficient method for removing hazardous 2,4-D from water environments, which contributes to addressing pressing environmental problems.


Subject(s)
2,4-Dichlorophenoxyacetic Acid , Charcoal , Iron , Water Pollutants, Chemical , Water Purification , 2,4-Dichlorophenoxyacetic Acid/chemistry , Charcoal/chemistry , Water Pollutants, Chemical/chemistry , Water Purification/methods , Iron/chemistry , Peroxides/chemistry , Herbicides/chemistry , Oxidation-Reduction , Adsorption , Catalysis
13.
Water Environ Res ; 96(8): e11099, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39155047

ABSTRACT

In this study, we employed the response surface method (RSM) and the long short-term memory (LSTM) model to optimize operational parameters and predict chemical oxygen demand (COD) removal in the electrocoagulation-catalytic ozonation process (ECOP) for pharmaceutical wastewater treatment. Through RSM simulation, we quantified the effects of reaction time, ozone dose, current density, and catalyst packed rate on COD removal. Then, the optimal conditions for achieving a COD removal efficiency exceeding 50% were identified. After evaluating ECOP performance under optimized conditions, LSTM predicted COD removal (56.4%), close to real results (54.6%) with a 0.2% error. LSTM outperformed RSM in predictive capacity for COD removal. In response to the initial COD concentration and effluent discharge standards, intelligent adjustment of operating parameters becomes feasible, facilitating precise control of the ECOP performance based on this LSTM model. This intelligent control strategy holds promise for enhancing the efficiency of ECOP in real pharmaceutical wastewater treatment scenarios. PRACTITIONER POINTS: This study utilized the response surface method (RSM) and the long short-term memory (LSTM) model for pharmaceutical wastewater treatment optimization. LSTM predicted COD removal (56.4%) closely matched experimental results (54.6%), with a minimal error of 0.2%. LSTM demonstrated superior predictive capacity, enabling intelligent parameter adjustments for enhanced process control. Intelligent control strategy based on LSTM holds promise for improving electrocoagulation-catalytic ozonation process efficiency in pharmaceutical wastewater treatment.


Subject(s)
Biological Oxygen Demand Analysis , Ozone , Waste Disposal, Fluid , Wastewater , Water Pollutants, Chemical , Ozone/chemistry , Wastewater/chemistry , Water Pollutants, Chemical/chemistry , Waste Disposal, Fluid/methods , Catalysis , Water Purification/methods , Electrocoagulation/methods , Pharmaceutical Preparations/chemistry
14.
Sci Total Environ ; 832: 155071, 2022 Aug 01.
Article in English | MEDLINE | ID: mdl-35395298

ABSTRACT

This review renewed insight into the existing complex and contradictory mechanisms of catalytic ozonation by two-dimensional layered carbon-based materials (2D-LCMs) for degradation toxic refractory organics in aqueous solution. Migration and capture of active electrons are central to catalytic ozonation reactions, which was not studied or reviewed more clearly. Based on this perspective, the catalytic ozonation potential of 2D-LCMs synthesized by numerous methods is firstly contrasted to guide the design of subsequent carbon based-catalysts, and not limited to 2D-LCMs. Matching ROS to active sites is a key step in understanding the catalytic mechanism. The structure-activity relationships between reported numerous active sites and ROS evolution is then constructed. Result showed that OH could be produced by -OH, -C=O, -COOH groups, defective sites, immobilized metal atoms, doped heteroatoms and photo-induced electrons; and O2- could be produced by -OH groups and sp2-bonded carbon. The normalized model further be used to visually compare the contribution degree of various regulatory methods to performance improvement. More importantly, this review calls for 2D-LCMs-based catalytic ozonation to be studied without circumventing the issue of structural stability, which would lead to many proposals of catalysts and its involved catalytic reaction mechanism being meaningless.


Subject(s)
Ozone , Water Pollutants, Chemical , Water Purification , Carbon , Catalysis , Ozone/chemistry , Reactive Oxygen Species , Water Pollutants, Chemical/analysis
15.
Water Res ; 226: 119244, 2022 Nov 01.
Article in English | MEDLINE | ID: mdl-36270143

ABSTRACT

An efficient in-situ self-cleaning catalytic ceramic-membrane tailored with MnO2-Co3O4 nanoparticles (Mn-Co-CM) was fabricated. Density functional theory calculations result substantiated that molecular ozone could be effectively adsorbed by oxygen vacancies (OV) on the Mn-Co-CM surface and then direct activated into a surface-bound atomic oxygen (*Oad) and a peroxide (*O2, ad), ultimately producing ·OH. Mn-Co-CM coupling with ozone efficiently removed foulants from the permeate and the membrane surface simultaneously and leading to in-situ formation of ·OH that changed the nature of the irreversible foulants and ultimately resulted in the rapid release and degradation of humic acid-like substances causing irreversible fouling. However, the commercial CM with ozone mainly removed cake layer fouling including protein-like and fulvic acid-like substances, followed by the slow release and degradation of irreversible foulant, resulting in many humic acid-like substances remain on the membrane surface as irreversible fouling. Based on these, the flux growth rate of Mn-Co-CM was 3.5 times higher than that of CM with ozone. This study provides new insights into the mechanism of in-situ membrane fouling mitigation, when using an efficient catalytic ceramic-membrane. This will facilitate the development of membrane antifouling strategies.


Subject(s)
Ozone , Water Purification , Oxides , Humic Substances , Membranes, Artificial , Manganese Compounds , Water Purification/methods
16.
Sci Total Environ ; 791: 148251, 2021 Oct 15.
Article in English | MEDLINE | ID: mdl-34139498

ABSTRACT

The presence of the non-steroidal anti-inflammatory drugs (NSAIDs) in the environment is a fact, and aquatic and soil organisms are chronically exposed to trace levels of these emerging pollutants. This review presents the current state of knowledge on the metabolic pathways of NSAIDs in organisms at various levels of biological organisation. More than 150 publications dealing with target or non-target analysis of selected NSAIDs (mainly diclofenac, ibuprofen, and naproxen) were collected. The metabolites of phase I and phase II are presented. The similarity of NSAIDs metabolism to that in mammals was observed in bacteria, microalgae, fungi, higher plants, invertebrates, and vertebrates. The differences, such as newly detected metabolites, the extracellular metabolism observed in bacteria and fungi, or phase III metabolism in plants, are highlighted. Metabolites detected in plants (conjugates with sugars and amino acids) but not found in any other organisms are described. Selected, in-depth studies with isolated bacterial strains showed the possibility of transforming NSAIDs into assimilable carbon sources. It has been found that some of the metabolites show higher toxicity than their parent forms. The presence of metabolites of NSAIDs in the environment is the cumulative effect of their introduction with wastewaters, their formation in wastewater treatment plants, and their transformation by non-target wild-living organisms.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal , Pharmaceutical Preparations , Animals , Diclofenac , Ibuprofen , Naproxen
17.
Anal Bioanal Chem ; 397(7): 3029-34, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20563796

ABSTRACT

Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most common groups of pharmaceuticals detected in environmental matrices. Although several derivatization procedures have been employed in the gas chromatographic analysis of NSAIDs, the application of trimethylsilyldiazomethane has never yet been reported. This work has studied the derivatization of widely used NSAIDs (ibuprofen, ketoprofen and naproxen) by trimethylsilyldiazomethane. Special emphasis was placed on the influence of temperature and reaction time on the reaction yield, and on the determination of the instrumental detection limit. The results are compared with those obtained by methylation using boron trifluoride methanol solution, and by silylation with a mixture of N,O-bis(trimethylsilyl)trifluoroacetamide and trimethylchlorosilane (99:1, v/v) and with N-methyl-N-[tert-butyldimethylsilyl]trifluoroacetamide. The derivatization of ibuprofen, ketoprofen and naproxen by trimethylsilyldiazomethane was shown to be simple, fast, efficient, and suitable for trace analysis (the respective instrumental detection limits for ibuprofen naproxen, and ketoprofen were 2, 4, and 4 ng). Trimethylsilyldiazomethane can be used as an alternative reagent for determining acidic drugs in environmental matrices.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/chemistry , Chromatography, Gas/methods , Diazomethane/analogs & derivatives , Trimethylsilyl Compounds/chemistry , Diazomethane/chemistry , Limit of Detection , Methylation
18.
Mar Drugs ; 8(5): 1567-636, 2010 Apr 29.
Article in English | MEDLINE | ID: mdl-20559489

ABSTRACT

Chitin, the second most important natural polymer in the world, and its N-deacetylated derivative chitosan, have been identified as versatile biopolymers for a broad range of applications in medicine, agriculture and the food industry. Two of the main reasons for this are firstly the unique chemical, physicochemical and biological properties of chitin and chitosan, and secondly the unlimited supply of raw materials for their production. These polymers exhibit widely differing physicochemical properties depending on the chitin source and the conditions of chitosan production. The presence of reactive functional groups as well as the polysaccharide nature of these biopolymers enables them to undergo diverse chemical modifications. A complete chemical and physicochemical characterization of chitin, chitosan and their derivatives is not possible without using spectroscopic techniques. This review focuses on the application of spectroscopic methods for the structural analysis of these compounds.


Subject(s)
Chitin/chemistry , Chitosan/chemistry , Spectrum Analysis/methods , Chitin/isolation & purification , Chitosan/isolation & purification , Magnetic Resonance Imaging/methods , Mass Spectrometry/methods , Molecular Structure , Spectroscopy, Fourier Transform Infrared/methods
19.
Chemosphere ; 248: 125976, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32006830

ABSTRACT

In this study, biochars (BCs) produced from crops (straw and seeds) were tested for the applicability as additive to soils. The effect on pH, water capacity and cation exchange capacity of soil were tested. The ability for the sorption of pharmaceuticals (beta-blockers, anti-inflammatory drugs, sulfonamides, 17α-ethinylestradiol, carbamazepine, caffeine) using the batch sorption test was performed, and the effect of water pH was investigated. In addition, the metals removed from the biochar was analyzed as a potential toxicity factor. The mechanism of adsorption (Langmuir, Freundlich) was tested for sulfadimetoxine. The effect of the rye-derived biochar on water cress germination and the reduction of the sulfonamides toxicity to this plant was tested. The advantages of crop-derived biochar application to different soils (sand soil, clay soil and reference soil) was presented. It was found that tested BCs effectively increase the water capacity of soils, especially sand type soil, but in the same time it had increase the pH of pure-buffering soils. The driving force of pharmaceutical sorption was its ionization form - the highest sorption occurs for cations, medium for neutral forms, while the lowest sorption for anions. The opposite situation have been noted for desorption from biochar. The washing of biochars increases sorption for the neutral and anionic species, but not for the cations. The application of biochars into the soils can from one site protect the plants from toxic impact of sulfonamides, but from the other hamper the root prolongation by the pH increase.


Subject(s)
Agriculture/methods , Charcoal/chemistry , Fertilizers , Adsorption , Cations , Soil , Soil Pollutants/analysis
20.
Sci Total Environ ; 697: 134023, 2019 Dec 20.
Article in English | MEDLINE | ID: mdl-31479900

ABSTRACT

The intensive use of antibiotics for human, veterinary and agricultural purposes, results in their continuous release into the environment. Together with antibiotics, antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) are introduced into wastewater. Wastewater treatment plants (WWTPs) are believed to be probable hotspots for antibiotic resistance dissemination in the environment as they offer convenient conditions for ARB proliferation as well as for horizontal transfer of ARGs among different microorganisms. In fact, genes conferring resistance to all classes of antibiotics together with mobile genetic elements (MGEs) like plasmids, transposons, bacteriophages, integrons are detected in WWTPs in different countries. It seems that WWTPs with conventional treatment processes are capable of significant reduction of ARB but are not efficient in ARG removal. Implementation of advanced wastewater cleaning processes in addition to a conventional wastewater treatment is an important step to protect the aquatic environment. Growing interest in presence and fate of ARB and ARGs in WWTP systems resulted in the fact that knowledge in this area has increased staggeringly in the past few years. The main aim of the article is to collect and organize available data on ARGs, that are commonly detected in raw sewage, treated wastewater or activated sludge. Resistance to the antibiotics usually used in antibacterial therapy belonging to main classes like beta-lactams, macrolides, quinolones, sulfonamides, trimethoprim and tetracyclines was taken into account. The presence of multidrug efflux genes is also included in this paper. The occurrence of antibiotics may promote the selection of ARB and ARGs. As it is important to discuss the problem considering all aspects that influence it, the levels of antibiotics detected in influent and effluent of WWTPs were also presented.


Subject(s)
Drug Resistance, Microbial/genetics , Waste Disposal, Fluid , Wastewater/microbiology , Genes, Bacterial
SELECTION OF CITATIONS
SEARCH DETAIL