Use of CdS from Teaching-Laboratory Wastes as a Photocatalyst for the Degradation of Fluoroquinolone Antibiotics in Water

Laboratory wastes containing Cd2+ and water polluted by pharmaceuticals represent an environmental concern. In this work, a proof concept, consisting of the use of teaching-laboratory wastes to synthesize CdS and its subsequent use as a photocatalyst to degrade fluoroquinolone antibiotics, was developed. The CdS was prepared by extraction with thioacetamide and calcination (at 450 °C) and characterized using several techniques. The photocatalytic activity of the CdS, to degrade levofloxacin and norfloxacin, was tested, and the routes involved in the process and the primary transformations of the fluoroquinolones were established. Moreover, the ability of CdS-photocatalysis to eliminate levofloxacin in simulated matrices of fresh urine and hospital wastewater was evaluated. The characterization analyses indicated that the CdS semiconductor was synthesized successfully. Effectively, the CdS acted as a photocatalyst toward degradation of levofloxacin, involving the action of superoxide anion radical, holes, and singlet oxygen mainly. The process induced transformations on the methyl-piperazyl moiety, plus hydroxylation of the fluoroquinolone nucleus on levofloxacin. Additionally, CdS-photocatalysis was highly selective for the elimination of the target pollutant in both tested matrices. Our research indicated the good potentiality of recycling teaching-laboratory wastes to generate photocatalysts to degrade organic pollutants. This work was presented at 4° Congreso Colombiano de Procesos Avanzados de Oxidación (4CCPAOx)

Methods involved in the treatment of four representative pharmaceuticals in hospital wastewater using sonochemical and biological processes

A primary pollution source by pharmaceuticals is hospital wastewater (HWW). Herein, the methods involved in the action of a biological system (BS, aerobic activated sludge) or a sonochemical treatment (US, 375 kHz and 30.8 W), for degrading four relevant pharmaceuticals (azithromycin, ciprofloxacin, paracetamol, and valsartan) in HWW, are shown. Before treatment of HWW, the correct performance of BS was assessed using glucose as a reference substance, monitoring oxygen consumption, and organic carbon removal. Meanwhile, for US, a preliminary test using ciprofloxacin in distilled water was carried out. The determination of risk quotients (RQ) and theoretical analyses about reactive moieties on these target substances are also presented. For both, the degradation of the pharmaceuticals and the calculation of RQ, analyses were performed by LC-MS/MS. The BS action decreased the concentration of paracetamol and valsartan by ∼96 and 86%, respectively. However, a poor action on azithromycin (2% removal) was found, whereas ciprofloxacin concentration increased ∼20%; leading to an RQ value of 1.61 (high risk) for the pharmaceuticals mixture. The analyses using a biodegradation pathway predictor (EAWAG-BDD methodology) revealed that the amide group on paracetamol and alkyl moieties on valsartan could experience aerobic biotransformations. In turn, US action decreased the concentration of the four pharmaceuticals (removals > 60% for azithromycin, ciprofloxacin, and paracetamol), diminishing the environmental risk (RQ: 0.51 for the target pharmaceuticals mixture). Atomic charge analyses (based on the electronegativity equalization method) were performed, showing that the amino-sugar on azithromycin; piperazyl ring, and double bond close to the two carbonyls on ciprofloxacin, acetamide group on paracetamol, and the alkyl moieties bonded to the amide group of valsartan are the most susceptible moieties to attacks by sonogenerated radicals. The LC-MS/MS analytical methodology, RQ calculations, and theoretical analyses allowed for determining the degrading performance of BS and US toward the target pollutants in HWW

Sonochemical degradation of antibiotics from representative classes-Considerations on structural effects, initial transformation products, antimicrobial activity and matrix

In this work, the sonochemical treatment (at 354 kHz and 88 W L-120 ) of six relevant antibiotics belonging to fluoroquinolones (ciprofloxacin and norfloxacin), penicillins (oxacillin and cloxacillin) and cephalosporins (cephalexin and cephadroxyl) classes was evaluated. Firstly, the ability of the process to eliminate them was tested, showing that sonodegradation of these antibiotics is strongly chemical structure25 dependent. Thus, correlations among initial degradation rate of pollutants (Rd), solubility in water (Sw), water-octanol partition coefficient (Log P) and topological polar surface area (TPSA) were tested. Rd exhibited a good correlation with Log P (i.e., the hydrophobicity degree of antibiotics). The considered penicillins had the fastest elimination and from the constitutional analysis using Lemke method was clear that the functional groups arrangement on these antibiotics made them highly hydrophobics. The penicillins were degraded closer at cavitation bubble than the fluoroquinolones or cephalosporins. The investigation of degradation products showed that sonogenerated hydroxyl radical primary attacked the β-lactam ring of cloxacillin and cephalexin, whereas on norfloxacin induced a decarboxylation. On the other hand, the evolution of antimicrobial activity was also followed. It was evidenced the process capacity to remove antimicrobial activity from treated solutions, which was associated to the transformations of functional groups on antibiotics with important role for interaction with bacteria. Additionally, degradation of antibiotics having the highest (the most hydrophobic, i.e., cloxacillin) and lowest (the most hydrophilic, i.e., cephadroxyl) Rd, was performed in synthetic matrices (hospital wastewater and seawater). Ultrasound degraded both antibiotics; for cloxacillin in such waters higher eliminations than in distilled water were observed (probably due to a salting-out effect exerted by matrix components). Meanwhile, for cephadroxyl a moderate inhibition of degradation in hospital wastewater and seawater respect to distilled water was found, this was related to competition by hydroxyl radical of the other substances in the matrices. These results show the quite selectivity of high frequency ultrasound to eliminate antibiotics form different classes even in complex matrices

Degradation of seventeen contaminants of emerging concern in municipal wastewater effluents by sonochemical advanced oxidation processes

The simultaneous degradation of seventeen emerging concern pollutants in effluent from the municipal wastewater treatment plant (MWTP) of Bogotá-Colombia was studied using high frequency ultrasound (375 kHz). The considered compounds in the effluent corresponded to pharmaceuticals (diclofenac, carbamazepine, venlafaxine, ciprofloxacin, norfloxacin, valsartan, losartan, irbesartan, sulfamethoxazole, clarithromycin, azithromycin, erythromycin, metronidazole, trimethoprim and the high potentiality of the sono-photo-Fenton/oxalic acid system for the pollutants elimination in real-world wastewater matrices. clindamycin); cocaine and its major metabolite benzoylecgonine. Due to limitation of the MWTP for the pollutants elimination, ultrasound was applied to remove these compounds. Interestingly, ultrasonic physical action led to releasing of ciprofloxacin, norfloxacin, diclofenac and sulfamethoxazole from suspended solids, whereas the chemical effects induced degradation of the rest of compounds. For the latter ones, an interesting correlation between the sonodegradation and arithmetic multiplication between hydrophobicity and concentration of pollutants was established. Afterwards, the sonochemical process was complemented with ferrous ions (sono-Fenton), ferrous ions plus light (sono-photo-Fenton) or ferrous ions plus light in presence of oxalic acid (sono-photo-Fenton/oxalic acid). Additionally, to clarify fundamental aspects of the different systems, individual treatments in distilled water of a model pollutant (valsartan) were performed. The complemented processes significantly enhanced all compounds degradation, following the order: sono-photo-Fenton/oxalic acid > sono-photo-Fenton ~ sono-Fenton > sonochemistry. The Fe2+ addition improved the pollutants elimination by generation of more hydroxyl radicals in the solution bulk. Meanwhile, oxalic acid avoided Fe3+ precipitation favoring the iron catalytic cycle. Thus, the work demonstrate

Design of ancillary service markets and products: Challenges and recommendations for EU renewable power systems: Deliverable D3.3

Project TradeRES - New Markets Design & Models for 100% Renewable Power Systems: https://traderes.eu/about/ABSTRACT: The overall objective of the current study is to analyse the implications of the transition towards a renewable, climate-neutral power system in the EU for the demand and supply of ancillary services (AS) of this system in general and for the market design and related EU regulation of these services in particular. The study focuses predominantly on electricity balancing services (‘frequency control’). However, other ancillary services – not ably reactive power services (‘voltage control’) and system restoration services (‘black start’) – are, to some extent, considered as well. More specifically, the study analyses in particular (i) the current situation (‘base case’) of ancillary (electricity balancing) services in the EU, (ii) the future situation (‘towards a 100% renewable EU power system’) of these services, and (iii) the major challenges and recommendations for the main ancillary services markets in the EU in order to improve the performance of these markets in the coming years, i.e. up to 2030 and beyond.N/

Open-access tool of linked electricity market models: Deliverable D4.8

Project TradeRES - New Markets Design & Models for 100% Renewable Power Systems: https://traderes.eu/about/ABSTRACT: For a holistic understanding and simulation of the energy markets, many different aspects need to modelled properly. Often no single modelling tool offers the whole picture, but a combination of methods needs to be used. A model linkage platform has been chosen previously and this deliverable describes the integration of the modelling tools used in TradeRES to the linking application, Spine Toolbox. Spine Toolbox was used to build data processing and execution workflows around the energy system modelling tools Backbone, AMIRIS, EMLab, COMPETES, RESTrade and MASCEM. The aim is to integrate selected tools together for answering the research questions in the TradeRES project. The integrations of individual tools and some combinations are described in this document. Mostly, the work is still in progress. Also, a common database to serve the case studies has been created, but populating the database with scenario data is still in progress. A common data model to serve all the modelling tools has been created and the database is implemented using Spine Toolbox.N/

Characterization of new flexible players: Deliverable D3.2

Project TradeRES - New Markets Design & Models for 100% Renewable Power Systems: https://traderes.eu/about/ABSTRACT: The subject matter of this report is the analysis of the electricity markets’ actors’ scene, through the identification of actor classes and the characterisation of actors from a behavioural and an operational perspective. The technoeconomic characterization of market participants aims to support the upcoming model enhancements by aligning the agent-based model improvements with the modern market design challenges and the contemporary characteristics of players. This work has been conducted in the context of task T3.2, which focuses on the factorization of the distinctive operational and behavioural characteristics of players in market structures. Traditional parties have been considered together with new and emerging roles, while special focus has been given on new actors related to flexible technologies and demand-side response. Among the main objectives have been the characterization of individual behaviours, objectives and requirements of different electricity market players, considering both the traditional entities and the new distributed ones, and the detailed representation of the new actors.N/

Market design for a reliable ~100% renewable electricity system: Deliverable D3.5

Project TradeRES - New Markets Design & Models for 100% Renewable Power Systems: https://traderes.eu/about/ABSTRACT: The goal of this report is to identify in which respects the design and regulation of electricity markets needs to be improved in order facilitate a (nearly) completely decarbonized electricity system. It provides a basis for scoping the modeling analyses that are to be performed in subsequent work packages in the TradeRES project. These simulations will provide the basis for an update of this deliverable in the form of a more precise description of an all-renewable electricity market design. In this first iteration1 of deliverable 3.5, we analyze how the current design of electricity markets may fall short of future needs. Where there is a lack of certainty about the best market design choices, we identify alternative choices. Alternatives may concern a choice between policy intervention and no intervention or different intervention options. Section 2 outlines current European electricity market design and the key pieces of European legislation that underlie it. The European target model is zonal pricing with bidding zones that are defined as geographic areas within the internal market without structural congestion. That implies that within one bidding zone electricity can be traded without considering grid constraints and there are uniform wholesale prices in each zone. The main European markets are Nordpool, EPEX and MIBEL. Trading between zones in the European Price Coupling Region occurs through an implicit auction where price and quantity are computed for every hour of the next day, using EUPHEMIA, a hybrid algorithm for flowbased market coupling that is considered the best practice in Europe at this time.N/

Spatial flexibility options in electricity market simulation tools: Deliverable D4.3

Project TradeRES - New Markets Design & Models for 100% Renewable Power Systems: https://traderes.eu/about/ABSTRACT: Deliverable D4.3 addresses the spatial flexibility options that are being considered by TradeRES models. D4.3 presents a report describing the spatial flexibility-related modelling components that are already implemented and those that are being designed for integration in TradeRES agent-based models. This report includes the main definitions, concepts and terminology related to spatial flexibility, as means to support the presentation of the specific models that are being developed by the project, namely about flow based market coupling, market spliting, nodal pricing, dynamic line rating, cross border intraday market, cross border reserve market, cross border capacity market, consumer flexibility aggregation, renewable energy aggregation, storage aggregation, electric vehicle aggregation and grid capacity.N/