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Mesostructured PbO2/TiO2 materials were synthesized to perform electrocatalysis (as electrooxidation, EO) and photoelectrocatalysis for removing diclofenac (DCF), 15 ppm concentration in 0.1 M NaSO4 solutions, at different pH conditions (3.0, 6.0 and 9.0) by applying 30 mA cm-2. Titania nanotubes (TiO2NTs)-based materials were prepared to synthetize with a massive PbO2 deposit on this support to obtain TiO2NTs/PbO2 and a TiO2NTs:PbO2 material consisting in a dispersed PbO2 deposit on TiO2-NTs that allowed the formation of a heterostructured surface of combined composition (TiO2 and PbO2). Organics removal (DCF and byproducts) was monitored through UV-vis spectrophotometry and high-performance liquid chromatography (HPLC) during degradation tests. TiO2NTs/PbO2 electrode was tested in both processes, removing DCF at neutral and alkaline solution conditions in EO while an unimportant photoactivity was registered at this material. Conversely, TiO2NTs:PbO2 was used as electrocatalytic material in EO experiments, achieving more than 50% of DCF removal at pH 6.0 by applying 30 mA cm-2. Also, for first time, the synergic effect was investigated when it was exposed to UV irradiation in photoelectrocatalytic experiments, enhancing its efficacy (⁓more than 20%) to remove DCF from a solution with 15 ppm over performance removals achieved (56%) when EO was applied under similar conditions. Chemical Oxygen Demand (COD) analyses showed that significantly higher DCF degradation is reached under photoelectrocatalysis, since COD values decrease a 76% against a 42% decrease achieved with electrocatalysis. Scavenging experiments showed a significant participation on the pharmaceutical oxidation process through the generation of photoholes (h+), hydroxyl radicals and sulfate-based oxidants.

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The increasing demand and implementation of pharmaceutics poses severe risk to different aquatic species as detectable contaminant in almost every surface water worldwide. Diclofenac (DCF) as one of the most common used analgesics was investigated as contaminant to be removed by adsorption onto nanoporous poly(melamine-co-formaldehyde) (PMF) particles featuring a very high amount of nitrogen functionalities. To achieve a high specific surface area (up to 416 m2/g) and a tunable pore system by hard templating, four different SiO2 nanoparticles were used as template. Differences in the pore formation and achieved pore structure were elucidated. For the first time, the adsorption of DCF onto PMF was tested. In batch adsorption experiments, impactful adsorption capacities as high as 76 µmol/g were achieved and complete removal at initial concentrations of 2 mg/L DCF. Differences in the connectivity and the micropore structure were decisive for uptake in low concentrations and the achieved adsorption capacity, respectively. As the presented PMF particles can be easily synthesized with the monomers formaldehyde and melamine combined with colloidal silica as sacrificial template and water as green solvent, this material presents a viable adsorbent for the removal of DCF at a larger scale. Our study further indicates a high potential for the removal of other pharmaceuticals.

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Diclofenac (DFC) is a pharmacologically active compound frequently detected in various receiving waters. To improve the efficiency of constructed wetlands in removing DFC, biochar (BC) is added as a substrate. The study mainly involved the effect of adding wetland plant-derived BC to vertical subsurface flow constructed wetlands (VSF-CWs) on the DFC removal process. In addition, the study discussed the effects of the initial DFC concentration (0.05-1.00 mg L-1), pH (5.5-8.5), and hydraulic retention times (HRTs, 1-7 d) on the removal process and fluctuations in the microbial community. Preliminary results of the study showed optimal removal (>90%) achieved at an initial DFC concentration of 0.75-1 mg L-1, a pH of 6.5-7.5, and an HRT of 7 d. Moreover, no significant effects on the removal efficiency of conventional water quality parameters were observed. Non-metric multidimensional scaling results revealed a reshaped community structure, which was altered by the initial DFC concentration. DFC concentration is a key factor in the variation of microbial communities and controls the quantitative evolution of the species in experimental units. Therefore, the addition of BC to CWs effectively enhanced the removal efficiency of DFC and provided a viable and effective improvement of the CWs.

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Present research was directed towards the development of new high-performance and cost-effective polysulfone membranes (PSFQ) by introducing ionic liquids (ILs-Cyphos 101 IL and Aliquat 336) into their matrix. Variation of ILs was performed with the aim to find the one that brings new properties and improves the functionality and selectivity of PSFQ membranes in ultrafiltration processes. Based on the obtained results of the rheological study, we established the compatibility of compounds and optimal content of the used ILs, namely 3 wt% and 15 wt% Cyphos 101 IL and compositions varying between 3 and 15 wt % Aliquat 336. Results indicated that the ILs acted as plasticizers when they were added to the system, a helpful aspect in processing membranes used in water decontamination. The efficiency and performance of the membranes were evaluated by their use in the treatment of diclofenac (DCF)-containing waters. Membranes obtained from PSFQ/Aliquat 336 solution containing 15 wt% IL exhibited a 97% removal degree of DCF in the treatment process of 50 mL solution containing 3 mg/L DCF. The separation efficiency was kept constant for four filtration/cleaning cycles. The results indicated an improvement in membrane performance as the amount of IL in their structure increased, which confirms the potential for application in water treatment processes.

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Diclofenac (DCF), as a typical representative of PPCPs, has potential ecotoxicity to the water environment. In this study, ultrasound (US) enhanced ferrous sulfide (FeS)-activated persulfate (PDS) technology (US/FeS/PDS) was used to degrade DCF. By comparing the degradation effects of US, US/PDS, FeS/PDS and US/FeS/PDS systems on DCF, this study confirmed the synergy and strengthening effects of US. The influences of single-factor experimental conditions on the US/FeS/PDS system were investigated and optimized. The FeS catalysts before and after the reaction were characterized and analyzed by X-ray diffractometer (XRD) and X-ray photoelectron spectroscopy (XPS). The heterogeneous reaction proceeded on the surface of FeS, and a small part of FeS2 was formed on FeS surface. During the reaction, the proportion of S2- on the catalyst surface decreased from 51% to 44%. Correspondingly, the proportion of Sx2- increased from 21% to 26%. It indicated that S2- was oxidized into Sx2- in the reaction, and the loss electrons of S2- caused the reduction of Fe3+ to Fe2+on the FeS surface, which promoted the cycle between Fe2+ and Fe3+ in turn. Furthermore, SO4- and ‧OH were the main active free radicals, of which the contribution rate of ‧OH was about 34.4%, while that of SO4- was approximately 52.2%. In US/FeS/PDS, the introduction of US could promote the dissolution of iron on the FeS surface. US contributed to the formation of a redox power motor between S2-Sx2- and Fe2+-Fe3+, which continuously decomposed PDS to generate sufficient active SO4- and ‧OH radicals, thereby efficiently and continuously degrading DCF. Finally, the related mechanism of DCF degradation by US/FeS/PDS was summarized. Overall, US/FeS/PDS can not only efficiently degrade and remove DCF, but also has potential application value in organic pollution removal and wastewater purification.

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Bioremediation with immobilized enzymes has several advantages, such as the enhancement of selectivity, activity, and stability of biocatalysts, as well as enzyme reusability. Laccase has proven to be a good candidate for the removal of a wide range of contaminants. In this study, naked or modified MnFe2O4 magnetic nanoparticles (MNPs) were used as supports for the immobilization of laccase from Trametes versicolor. To increase enzyme loading and stability, MNPs were coated with chitosan both after the MNP synthesis (MNPs-CS) and during their formation (MNPs-CSin situ). SEM analysis showed different sizes for the two coated systems, 20 nm and 10 nm for MNPs-CS and MNPs-CSin situ, respectively. After covalent immobilization of laccase by glutaraldehyde, the MNPs-CSin situ-lac and MNPs-CS-lac systems showed a good resistance to temperature denaturation and storage stability. The most promising system for use in repeated batches was MNPs-CSin situ-lac, which degraded about 80% of diclofenac compared to 70% of the free enzyme. The obtained results demonstrated that the MnFe2O4-CSin situ system could be an excellent candidate for the removal of contaminants.

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In this paper, the influence of several aquatic factors (the nature of catalyst, the initial pH and the initial concentration of the pollutant) on the photocatalytic degradation of diclofenac (DFC), one of the most widely prescribed anti-inflammatory non-steroidal drug, was studied. Also, in order to examine the intensification process, the variation of the photocatalytic DFC degradation in the presence of sodium persulfate (PPS) was analyzed. It was found that, compared to titanium dioxide (TiO2), the zinc oxide (ZnO) photocatalyst performed exceptionally well, with a 96.13% DFC degradation efficiency after 150 min. The photodegradation of DFC by ZnO catalyst fitted well the Langmuir-Hinshelwood kinetic model. The maximum efficiency is 97.27% for simulated solar-UVA/ZnO/PPS and 77% for simulated solar-UVA/ZnO. In order to determine the optimal conditions leading to the maximization of DFC removal, an artificial neural network (ANN) modeling approach combined with genetic algorithm (GA) was applied. The best ANN determined had a correlation of 0.999 and it was further used in the process optimization where a 99.7% degradation efficiency was identified as the optimum under the following conditions: DFC initial concentration 37,9 mg L-1, pH 5,88 and PPS initial concentration 500 mg L-1. The effectiveness of the process and the toxicity of the pharmaceutical pollutants and their by-products were also evaluated and confirmed by the biological tests using liver and kidney of Mus musculus mice.

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The removal of diclofenac sodium (DFS) from wastewater has attracted increasing attention because it is within the extensively prescribed nonsteroidal anti-inflammatory drugs and pose ecotoxicity. Therefore, fabrication of versatile adsorbents of low-cost, higher-effectiveness and excellent recyclability is significant for the treatment of DFS contaminated wastewater. This work reports a promising biobased egg albumin (ALB) hydrogel functionalized with a large density of adsorptive amine sites via polyethyleneimine (PEI). The composite ALB/PEI hydrogel demonstrated an excellent DFS removal capacity, i.e. 232.5 mg/g, in an optimum experimental condition (pH∼6; contact time∼180 min; adsorbent dosage∼0.5 g/L) which revealed to be considerably higher or competitive than many reported adsorbents. The adsorption isotherms better accorded with the Langmuir model and the kinetics with the pseudo second-order model, indicating the mono-layer chemisorption process. Besides, the regeneration steps up to four sequential adsorption/desorption cycles demonstrated an excellent reusability. The Fourier-transform infrared spectrometry (FTIR), and X-ray photoelectron spectroscopy (XPS) results implied that the adsorption process followed via the electrostatic interactions, hydrogen bonding, and π-π stacking between the functionality of hydrogel and aromatic rings of DFS. Considering the low-cost, and an excellent DFS removal capacity, the natural composite ALB/PEI hydrogel could be a promising adsorbent for the treatment of DFS contaminated wastewater.

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The usage of low cost material as adsorbent would be admirable from environmental point of view. Thus, herein, this data set present a simple method for providing an adsorbent from activated carbon derived from pine tree. The prepared adsorbent was applied to remove diclofenac from aqueous solution. The characterization data of the adsorbent was analyzed using FTIR method. The FTIR test results showed that adsorbent has a functional group that is useful in adsorption process. It was conducted in laboratory scale and the adsorption technique was batch technique. The information regarding isotherms of diclofenac adsorption were listed. The Langmuir isotherm was suitable for correlation of equilibrium data with correlation coefficient value of 0.999. Adsorption of diclofenac by adsorbent from activated carbon follows pseudo second order model with correlation coefficient value (R2) of 0.9997. The data implied that the maximum adsorption capacity of adsorbent to uptake diclofenac from aqueous solution was obtained 54.67 mg/g. The acquired data indicated that the adsorption of diclofenac by the adsorbent prepared from activated carbon derived from pine tree is a promising technique for treating diclofenac bearing wastewaters.