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1.
Environ Res ; 246: 118162, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38218517

RESUMEN

This study investigated the application of adsorption with activated carbons (ACs) and photodegradation to reduce the concentration of triclosan (TCS) in aqueous solutions. Concerning adsorption, ACs (Darco, Norit, and F400) were characterised and batch experiments were performed to elucidate the effect of pH on equilibrium. The results showed that at pH = 7, the maximum adsorption capacity of TCS onto the ACs was 18.5 mg g-1 for Darco, 16.0 mg g-1 for Norit, and 15.5 mg g-1 for F400. The diffusional kinetic model allowed an adequate interpretation of the experimental data. The effective diffusivity varied and increased with the amount of TCS adsorbed, from 1.06 to 1.68 × 10-8 cm2 s-1. In the case of photodegradation, it was possible to ensure that the triclosan molecule was sensitive to UV light of 254 nm because the removal was over 80 % using UV light. The removal of TCS increased in the presence of sulfate radicals. It was possible to identify 2,4-dichlorophenol as one of the photolytic degradation products of triclosan, which does not represent an environmental hazard at low concentrations of triclosan in water. These results confirm that the use of AC Darco, Norit, and F400 and that photodegradation processes with UV light and persulfate radicals are effective in removing TCS from water, reaching concentration levels that do not constitute a risk to human health or environmental hazard. Both methods effectively eliminate pollutants with relatively easy techniques to implement.


Asunto(s)
Triclosán , Contaminantes Químicos del Agua , Humanos , Triclosán/química , Carbón Orgánico/química , Adsorción , Fotólisis , Agua , Contaminantes Químicos del Agua/análisis
2.
Environ Res ; 227: 115737, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-36972776

RESUMEN

As indicated in the call for papers posted for this Special Issue, Soil Science deals with various environmental compartments, so it is closely related to Environmental Research. It is clear that synergisms and collaboration are keys to reach the most fruitful relations among different sciences and scientists, and especially in all that focused on the Environment. In this line, considering Soil Science, Environmental Research, and the multiple and complex eventual combinations involving them, could give new highly interesting works focused on any of the specific subjects covered, as well as on relations among these sciences. The main objective should be going further in positive interactions that could help in protecting the Environment, proposing solutions to face hazards that are drastically threatening our planet. In view of that, the Editors of this Special Issue invited researchers to submit high-quality manuscripts including new experimental data, as well as scientifically founded discussion and reflections on the matter. The VSI has received 171 submissions, with 27% of them being accepted after peer-review. The Editors think that the papers included in this VSI have high scientific value and provide scientific knowledge on the field. In this editorial piece the Editors include comments and reflections on the papers published in the SI.

3.
J Environ Manage ; 338: 117830, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37004486

RESUMEN

Algae play an extremely important ecological role. They form the basis of trophic webs, produce oxygen that allows the respiration of many of the organisms in aquatic environments, absorb CO2, and serve as refuge areas and habitats for thousands of species. Many species can also absorb organic pollutants from seawater. Algae have been used for many centuries by humans as a source of food, fertilizer, fodder, and for the extraction of compounds with antifungal, antiviral, anticancer, and antibacterial properties. More recently, some species have been used for the production of biofuels. It has been shown that mixing small proportions of algae with the feed of cattle can reduce methane emissions from their digestive activity by more than 95%. One of the most widespread but least known applications of algae is the extraction of their phycocolloids for utilization in food, pharmaceutical, wine, and textile industries, among others. These compounds have gelling, stabilizing, and thickening properties and are therefore frequently included in creams, ice creams, cheeses, jellies, flavored milks, sauces, shampoos, medications, toothpaste, and many other products. The phycocolloids agar and carrageenan are extracted from red algae, whereas alginate is extracted from brown algae, being used in dental impressions, emulsifying lotions, and paints, among others, and in the preparation of wine and beer. Algae are of particular interest in the research and development of new biosorbent materials, not only because of their high adsorption capacity, but also because they are present in the seas and oceans in abundant and easily accessible quantities. Marine algae are a promising biosorbent for the removal of heavy metals and various pollutants and, due to their intrinsic characteristics, have received increasing attention in recent decades. Their application as biosorbents for the sorption of heavy metals and radionuclides could be interpreted as the use of waste to remove waste. Algae have attracted particular interest in the field of biotechnology for economic reasons, given that large amounts are naturally produced and left lying on beaches as waste material. The composition of algae biomass makes it a promising candidate for an extensive list of applications that continues to lengthen. The development of appropriate technologies and policies can transform the presence of algae in coastal ecosystems from an unpleasant and potentially harmful phenomenon into a source of major benefits. This review discusses the capacity of algae biomass to remove pollutants and also delves into its applicability in the production of dyes, oils, and biofuels and for animal feed and fertilizer industries, among others. Further research is warranted on strategies to convert a biomass that is currently considered waste into a means of addressing environmental problems.


Asunto(s)
Contaminantes Ambientales , Metales Pesados , Humanos , Animales , Bovinos , Biomasa , Ecosistema , Biocombustibles , Fertilizantes
4.
Environ Res ; 200: 111750, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34303683

RESUMEN

The objective of this study was to analyze the influence of different operational variables (catalyst loading, initial EtP concentration, medium pH, the presence of anions and radical scavengers) on the performance of ethylparaben (EtP) photodegradation catalyzed with an rGO/TiO2 composite. EtP was selected for study after analyzing the effect of paraben chain length on its catalytic photodegradation, finding that the photodegradation rate constant values of methyl-, ethyl-, and butyl-paraben are 0.050, 0.096, and 0.136 min-1, respectively. This indicates that the photodegradation rate constant of parabens is higher with longer alkyl chain, which augments its oxidation capacity. The percentage removal of EtP at 40 min increases from 66.3 to 98.6 % when the composite dose rises from 100 to 700 mg/L; however, an additional increase in the composite dose to 1000 mg/L does not substantively improve the photodegradation rate or percentage EtP removal (98.9 %). A rise in the initial EtP concentration from 15 to 100 mg/L reduces the percentage of degradation from 100 to 76.4 %. The percentage EtP degradation is lower with higher solution pH. The presence of HCO3- or Cl- anions in the medium reduces the degradation performance. Results obtained using positive hole and hydroxyl radical scavengers demonstrate that positive holes play an important role in EtP degradation. No degradation product evidences toxicity against the cultured human embryonic kidney cell line HEK-293.


Asunto(s)
Parabenos , Contaminantes Químicos del Agua , Grafito , Células HEK293 , Humanos , Fotólisis , Titanio , Rayos Ultravioleta , Contaminantes Químicos del Agua/análisis
5.
Molecules ; 25(24)2020 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-33371436

RESUMEN

In the present study, the synthesis of gold nanoparticles (AuNPs) loaded with methotrexate (MTX) has been carried out in order to obtain controlled size and monodispersed nanocarriers of around 20 nm. The characterization study shows metallic AuNPs with MTX polydispersed on the surface. MTX is linked by the replacement of citrate by the MTX carboxyl group. The drug release profiles show faster MTX release when it is conjugated, which leads to the best control of plasma concentration. Moreover, the enhanced release observed at pH 5 could take advantage of the pH gradients that exist in tumor microenvironments to achieve high local drug concentrations. AuNP-MTX conjugates were tested by flow cytometry against lung (A-549) and colon (HTC-116) cancer cell lines. Results for A-549 showed a weaker dose-response effect than for colon cancer ones. This could be related to the presence of folate receptors in line HTC-116 in comparison to line A-549, supporting the specific uptake of folate-conjugated AuNP-MTX by folate receptor positive tumor cells. Conjugates exhibited considerably higher cytotoxic effects compared with the effects of equal doses of free MTX. Annexin V-PI tests sustained the cell death mechanism of apoptosis, which is normally disabled in cancer cells.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias del Colon/tratamiento farmacológico , Oro/química , Neoplasias Pulmonares/tratamiento farmacológico , Nanopartículas del Metal/química , Metotrexato/farmacología , Células A549 , Anexina A5/metabolismo , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Colon/efectos de los fármacos , Colon/metabolismo , Neoplasias del Colon/metabolismo , Sistemas de Liberación de Medicamentos/métodos , Liberación de Fármacos/fisiología , Ácido Fólico/farmacología , Células HCT116 , Humanos , Concentración de Iones de Hidrógeno , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Neoplasias Pulmonares/metabolismo , Metotrexato/química , Microambiente Tumoral/efectos de los fármacos
6.
Environ Sci Technol ; 48(12): 7187-95, 2014 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-24837651

RESUMEN

A total of 12 commercial activated carbons (ACs) have been tested for the removal of octamethylcyclotetrasiloxane (D4) in dynamic adsorption experiments using different carrier gases and D4 concentrations. Characterization of the ACs included several physical and chemical techniques. The D4 adsorption capacities were strongly related with the textural development of the ACs. Results showed that the optimum adsorbent for D4 is a wood-based chemically activated carbon, which rendered an adsorption capacity of 1732 ± 93 mg g(-1) using 1000 ppm (v/v) of D4 with dry N2 as the carrier gas. When the concentration of D4 was lowered to typical values found in biogas, the adsorption capacity was halved. The presence of major biogas compounds (i.e., CH4 and CO2) and humidity further reduced the D4 adsorption capacity. The polymerization of D4 over the surface of all ACs was found to be relevant after prolonged contact times. The extent of this phenomenon, which may negatively affect the thermal regeneration of the AC, correlated reasonably well with the presence of phenolic and carboxylic groups on the carbon surfaces.


Asunto(s)
Biocombustibles/análisis , Carbón Orgánico/química , Siloxanos/aislamiento & purificación , Adsorción , Concentración de Iones de Hidrógeno , Espectroscopía de Fotoelectrones , Polimerizacion , Temperatura
7.
J Environ Manage ; 131: 16-24, 2013 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-24140483

RESUMEN

The objective of this study was to analyze the behavior of activated carbons with different chemical and textural natures in the adsorption of three tetracyclines (TCs) (tetracycline, oxytetracycline, and chlortetracycline). We also assessed the influence of the solution pH and ionic strength on the adsorption of these compounds and studied their removal by the combined use of microorganisms and activated carbon (bioadsorption). Sludge-derived materials were also used to remove TC from water. The capacity of these materials to adsorb TC was very high and was much greater than that of commercial activated carbon. This elevated adsorption capacity (512.1-672.0 mg/g) is explained by the high tendency of TC to form complex ions with some of the metal ions present in these materials. The medium pH and presence of electrolytes considerably affected TCs adsorption on commercial activated carbon. These results indicate that electrostatic adsorbent-adsorbate interactions play an important role in TC adsorption processes when conducted at pH values that produce TC deprotonation. The presence of bacteria during the TCs adsorption process decreases their adsorption/bioadsorption on the commercial activated carbon, weakening interactions between the adsorbate and the microfilm formed on the carbon surface. The adsorptive capacity was considerably lower in dynamic versus static regime, attributable to problems of TC diffusion into carbon pores and the shorter contact time between adsorbate and adsorbent.


Asunto(s)
Carbón Orgánico/química , Tetraciclina/química , Tetraciclina/aislamiento & purificación , Purificación del Agua/métodos , Adsorción , Aguas del Alcantarillado , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación
8.
Explor Res Clin Soc Pharm ; 9: 100229, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36866074

RESUMEN

Pharmacy and pharmaceutical sciences embrace a series of different disciplines. Pharmacy practice has been defined as "the scientific discipline that studies the different aspects of the practice of pharmacy and its impact on health care systems, medicine use, and patient care". Thus, pharmacy practice studies embrace both clinical pharmacy and social pharmacy elements. Like any other scientific discipline, clinical and social pharmacy practice disseminates research findings using scientific journals. Clinical pharmacy and social pharmacy journal editors have a role in promoting the discipline by enhancing the quality of the articles published. As has occurred in other health care areas (i.e., medicine and nursing), a group of clinical and social pharmacy practice journal editors gathered in Granada, Spain to discuss how journals could contribute to strengthening pharmacy practice as a discipline. The result of that meeting was compiled in these Granada Statements, which comprise 18 recommendations gathered into six topics: the appropriate use of terminology, impactful abstracts, the required peer reviews, journal scattering, more effective and wiser use of journal and article performance metrics, and authors' selection of the most appropriate pharmacy practice journal to submit their work.

9.
Res Social Adm Pharm ; 19(5): 830-835, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36804321

RESUMEN

Pharmacy and pharmaceutical sciences embrace a series of different disciplines. Pharmacy practice has been defined as "the scientific discipline that studies the different aspects of the practice of pharmacy and its impact on health care systems, medicine use, and patient care". Thus, pharmacy practice studies embrace both clinical pharmacy and social pharmacy elements. Like any other scientific discipline, clinical and social pharmacy practice disseminates research findings using scientific journals. Clinical pharmacy and social pharmacy journal editors have a role in promoting the discipline by enhancing the quality of the articles published. As has occurred in other health care areas (i.e., medicine and nursing), a group of clinical and social pharmacy practice journal editors gathered in Granada, Spain to discuss how journals could contribute to strengthening pharmacy practice as a discipline. The result of that meeting was compiled in these Granada Statements, which comprise 18 recommendations gathered into six topics: the appropriate use of terminology, impactful abstracts, the required peer reviews, journal scattering, more effective and wiser use of journal and article performance metrics, and authors' selection of the most appropriate pharmacy practice journal to submit their work.


Asunto(s)
Medicina , Farmacias , Investigación en Farmacia , Servicio de Farmacia en Hospital , Farmacia , Humanos
10.
Farm Hosp ; 47(3): T133-T138, 2023.
Artículo en Inglés, Español | MEDLINE | ID: mdl-37198084

RESUMEN

Pharmacy and pharmaceutical sciences embrace a series of different disciplines. Pharmacy practice has been defined as "the scientific discipline that studies the different aspects of the practice of pharmacy and its impact on health care systems, medicine use, and patient care". Thus, pharmacy practice studies embrace both clinical pharmacy and social pharmacy elements. Like any other scientific discipline, clinical and social pharmacy practice disseminates research findings using scientific journals. Clinical pharmacy and social pharmacy journal editors have a role in promoting the discipline by enhancing the quality of the articles published. As has occurred in other health care areas (i.e., medicine and nursing), a group of clinical and social pharmacy practice journal editors gathered in Granada, Spain to discuss how journals could contribute to strengthening pharmacy practice as a discipline. The result of that meeting was compiled in these Granada Statements, which comprise 18 recommendations gathered into six topics: the appropriate use of terminology, impactful abstracts, the required peer reviews, journal scattering, more effective and wiser use of journal and article performance metrics, and authors' selection of the most appropriate pharmacy practice journal to submit their work. © 2023 The Author(s) Published by Elsevier Inc, Springer Nature, Brazilian Society of Hospital Pharmacy and Health Services, Elsevier Inc, Royal Pharmaceutical Society, Biomedcentral, Sociedad Española de Farmacia Hospitalaria (S.E.F.H), Pharmaceutical Care España Foundation, European Association of Hospital Pharmacists, Faculty of Pharmacy.


Asunto(s)
Farmacias , Servicio de Farmacia en Hospital , Farmacia , Humanos , España , Farmacéuticos
11.
Int J Pharm Pract ; 31(2): 119-125, 2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-36933233

RESUMEN

Pharmacy and pharmaceutical sciences embrace a series of different disciplines. Pharmacy practice has been defined as 'the scientific discipline that studies the different aspects of the practice of pharmacy and its impact on health care systems, medicine use, and patient care'. Thus, pharmacy practice studies embrace both clinical pharmacy and social pharmacy elements. Like any other scientific discipline, clinical and social pharmacy practice disseminates research findings using scientific journals. Clinical pharmacy and social pharmacy journal editors have a role in promoting the discipline by enhancing the quality of the articles published. As has occurred in other healthcare areas (i.e. medicine and nursing), a group of clinical and social pharmacy practice journal editors gathered in Granada, Spain to discuss how journals could contribute to strengthening pharmacy practice as a discipline. The result of that meeting was compiled in these Granada Statements, which comprise 18 recommendations gathered into 6 topics, namely the appropriate use of terminology, impactful abstracts, the required peer reviews, journal scattering, more effective and wiser use of journal and article performance metrics and authors' selection of the most appropriate pharmacy practice journal to submit their work.


Asunto(s)
Servicios Farmacéuticos , Farmacias , Investigación en Farmacia , Farmacia , Humanos , España
12.
Farm Hosp ; 47(3): 133-138, 2023.
Artículo en Inglés, Español | MEDLINE | ID: mdl-36963994

RESUMEN

Pharmacy and pharmaceutical sciences embrace a series of different disciplines. Pharmacy practice has been defined as "the scientific discipline that studies the different aspects of the practice of pharmacy and its impact on health care systems, medicine use, and patient care". Thus, pharmacy practice studies embrace both clinical pharmacy and social pharmacy elements. Like any other scientific discipline, clinical and social pharmacy practice disseminates research findings using scientific journals. Clinical pharmacy and social pharmacy journal editors have a role in promoting the discipline by enhancing the quality of the articles published. As has occurred in other health care areas (i.e., medicine and nursing), a group of clinical and social pharmacy practice journal editors gathered in Granada, Spain to discuss how journals could contribute to strengthening pharmacy practice as a discipline. The result of that meeting was compiled in these Granada Statements, which comprise 18 recommendations gathered into six topics: the appropriate use of terminology, impactful abstracts, the required peer reviews, journal scattering, more effective and wiser use of journal and article performance metrics, and authors' selection of the most appropriate pharmacy practice journal to submit their work.


Asunto(s)
Farmacias , Servicio de Farmacia en Hospital , Farmacia , Humanos , España
13.
J Pharm Policy Pract ; 16(1): 43, 2023 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-36899408

RESUMEN

Pharmacy and pharmaceutical sciences embrace a series of different disciplines. Pharmacy practice has been defined as "the scientific discipline that studies the different aspects of the practice of pharmacy and its impact on health care systems, medicine use, and patient care". Thus, pharmacy practice studies embrace both clinical pharmacy and social pharmacy elements. Like any other scientific discipline, clinical and social pharmacy practice disseminates research findings using scientific journals. Clinical pharmacy and social pharmacy journal editors have a role in promoting the discipline by enhancing the quality of the articles published. As has occurred in other health care areas (i.e., medicine and nursing), a group of clinical and social pharmacy practice journal editors gathered in Granada, Spain to discuss how journals could contribute to strengthening pharmacy practice as a discipline. The result of that meeting was compiled in these Granada Statements, which comprise 18 recommendations gathered into six topics: the appropriate use of terminology, impactful abstracts, the required peer reviews, journal scattering, more effective and wiser use of journal and article performance metrics, and authors' selection of the most appropriate pharmacy practice journal to submit their work.

14.
Eur J Hosp Pharm ; 2023 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-36914239

RESUMEN

Pharmacy and pharmaceutical sciences embrace a series of different disciplines. Pharmacy practice has been defined as 'the scientific discipline that studies the different aspects of the practice of pharmacy and its impact on healthcare systems, medicine use, and patient care'. Thus, pharmacy practice studies embrace both clinical pharmacy and social pharmacy elements. Like any other scientific discipline, clinical and social pharmacy practice disseminates research findings using scientific journals. Clinical pharmacy and social pharmacy journal editors have a role in promoting the discipline by enhancing the quality of the articles published. As has occurred in other healthcare areas (ie, medicine and nursing), a group of clinical and social pharmacy practice journal editors gathered in Granada, Spain to discuss how journals could contribute to strengthening pharmacy practice as a discipline. The result of that meeting was compiled in these Granada Statements, which comprise 18 recommendations gathered into six topics: the appropriate use of terminology, impactful abstracts, the required peer reviews, journal scattering, more effective and wiser use of journal and article performance metrics, and authors' selection of the most appropriate pharmacy practice journal to submit their work.

15.
Int J Clin Pharm ; 45(2): 285-292, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36920737

RESUMEN

Pharmacy and pharmaceutical sciences embrace a series of different disciplines. Pharmacy practice has been defined as "the scientific discipline that studies the different aspects of the practice of pharmacy and its impact on health care systems, medicine use, and patient care". Thus, pharmacy practice studies embrace both clinical pharmacy and social pharmacy elements. Like any other scientific discipline, clinical and social pharmacy practice disseminates research findings using scientific journals. Clinical pharmacy and social pharmacy journal editors have a role in promoting the discipline by enhancing the quality of the articles published. As has occurred in other health care areas (i.e., medicine and nursing), a group of clinical and social pharmacy practice journal editors gathered in Granada, Spain to discuss how journals could contribute to strengthening pharmacy practice as a discipline. The result of that meeting was compiled in these Granada Statements, which comprise 18 recommendations gathered into six topics: the appropriate use of terminology, impactful abstracts, the required peer reviews, journal scattering, more effective and wiser use of journal and article performance metrics, and authors' selection of the most appropriate pharmacy practice journal to submit their work.


Asunto(s)
Farmacias , Investigación en Farmacia , Servicio de Farmacia en Hospital , Farmacia , Humanos , España
16.
Artículo en Inglés | MEDLINE | ID: mdl-36767922

RESUMEN

Sargassum algae has become a major environmental issue due to its abundance in the Pacific Ocean with hundreds of tons reaching the beaches of the Mexican Caribbean every year. This generates large quantities of decomposing organic matter that have a negative impact on the region's economy and ecosystems. Sargassum valorization has turned out to be a fundamental aspect to mitigate its environmental impact. This study proposes the use and application of untreated Sargassum biomass for the decontamination of waters polluted with lead (Pb) and cadmium (Cd) through single and binary adsorption tests. Physicochemical and textural properties examined by SEM, XRD, and FT-IR elucidated that Sargassum biomass is viable to be used as a potential environmental benign adsorbent, exhibiting Cd(II) and Pb(II) adsorption capacities as high as 240 mg g-1 and 350 mg g-1, respectively, outperforming conventionally used adsorbents. This is attributed to its morphology, favorable surface charge distribution, and the presence of -OH and -COH groups. A strong affinity between the biomass and metal pollutants was evidenced by a thermodynamics study, showing a spontaneous and endothermic process. This work sets a practical route for the utilization of the Sargassum biomass, demonstrating its applicability as a potential material for heavy-metal-polluted water remediation, making a substantial contribution to a circular economy system.


Asunto(s)
Metales Pesados , Sargassum , Contaminantes Químicos del Agua , Cadmio , Biomasa , Ecosistema , Espectroscopía Infrarroja por Transformada de Fourier , Plomo , Metales Pesados/química , Adsorción , Contaminantes Químicos del Agua/química
17.
J Environ Manage ; 109: 164-78, 2012 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-22796723

RESUMEN

This article describes the most recent methods developed to remove phthalic acid esters (PAEs) from water, wastewater, sludge, and soil. In general, PAEs are considered to be endocrine disrupting chemicals (EDCs), whose effects may not appear until long after exposure. There are numerous methods for removing PAEs from the environment, including physical, chemical and biological treatments, advanced oxidation processes and combinations of these techniques. This review largely focuses on the treatment of PAEs in aqueous solutions but also reports on their treatment in soil and sludge, as well as their effects on human health and the environment.


Asunto(s)
Ácidos Ftálicos/química , Agua Potable/química , Disruptores Endocrinos/química , Eliminación de Residuos Líquidos
18.
Nanomaterials (Basel) ; 10(7)2020 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-32698446

RESUMEN

A straightforward and economic procedure has been developed for the synthesis of a new polydopamine-like silica-based material that has been obtained by oxidation of catechol with KIO4 followed by reaction with 3-aminopropyltrimethoxysilane. All techniques adopted for characterization showed that the obtained material is rich in different functional groups and the morphological analyses revealed dimensions in the nanometric range. The hybrid material has been characterized by several techniques showing its polydopamine-like nature, and preliminary observations for dye adsorption have been reported.

19.
Sci Total Environ ; 669: 767-776, 2019 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-30897435

RESUMEN

This study investigated the adsorption of two endocrine-disrupting chemicals, bisphenol A (BPA) and S (BPS), from water using activated carbon clothes (ACCs), as-received and oxidized, in the absence and presence of bacteria, analyzing both kinetic and equilibrium adsorption data. Kinetic study of the different systems showed that the adsorption rate was affected both by the oxidation of the adsorbent and by the presence of bacteria. Bisphenol adsorption kinetics followed a second-order kinetic model, with rate constants between 0.0228 and 0.0013 g min-1 mol-1. ACC was a much better adsorbent of E. coli compared to granular activated carbons, achieving 100% adsorption at 24 h. ACC oxidation reduced the adsorption capacity and the adsorbent-adsorbate relative affinity due to the decrease in carbon surface hydrophobicity. Conversely, the presence of bacteria in aqueous solution increased the ACC surface hydrophobicity and therefore enhanced the adsorption capacity of BPA and BPS on ACC, which was 33% and 24%, respectively. In all cases, more BPS than BPA was removed due to the greater dipolar moment of the former. Results found show that activated carbon clothes in the presence of bacteria can be an adequate process to remove bisphenol A and S from different aqueous systems.


Asunto(s)
Compuestos de Bencidrilo/metabolismo , Biodegradación Ambiental , Escherichia coli/metabolismo , Fenoles/metabolismo , Contaminantes Químicos del Agua/metabolismo , Adsorción , Bacterias , Carbón Orgánico/química , Disruptores Endocrinos/metabolismo , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Cinética , Eliminación de Residuos Líquidos/métodos
20.
Sci Total Environ ; 569-570: 518-526, 2016 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-27366982

RESUMEN

Gamma radiation has been used to induce the degradation of compounds used as plasticizers and herbicides such as phthalic acid (PA), bisphenol A (BPA), diphenolic acid (DPA), 2,4-dichlorophenoxy-acetic acid (2,4-D), and 4-chloro-2-methylphenoxyacetic acid (MCPA) in aqueous solution, determining the dose constants, removal percentages, and radiation-chemical yields. The reaction rate constants of hydroxyl radical (HO), hydrated electron (eaq(-)) and hydrogen atom (H) with these pollutants were also obtained by means of competition kinetics, using 3-aminopyridine and atrazine as reference compounds. The results indicated that the elimination of these pollutants with gamma radiation mainly follows the oxidative pathway through reaction with HO radicals. The degradation by-products from the five pollutants were determined, detecting that the hydroxylation of the corresponding parent compounds was the main chemical process in the degradation of the pollutants. Moreover, a high decrease in the chemical oxygen demand has been observed for all pollutants. As expected, the degradation by-products generated by the irradiation of PA, BPA and DPA showed a lower toxicity than the parent compounds, however, in the case of 2,4-D and MCPA irradiation, interestingly, their by-products were more toxic than the corresponding original compounds.


Asunto(s)
Rayos gamma , Herbicidas/efectos de la radiación , Plastificantes/efectos de la radiación , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/efectos de la radiación
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