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A circular economy approach was followed to convert biomass wastes polluted with metals (obtained from phytoremediation processes) to generate electroactive carbon materials to be used in the electrochemical production of hydrogen peroxide. Carbon materials were pretreated using hydrothermal carbonization at 200ºC and 130 g soil mL−1 water and post treated through pyrolysis at different temperatures (300ºC, 500ºC and 1000ºC) and using different chemical precursors as KOH or H3PO4. These materials would modify the carbon paper (CP) cathodes to substitute the commonly used carbon black (CB), that comes from fossil fuels. Porosity, thermochemical behavior, electrical conductivity, electrocatalytic response and H2O2 accumulation tests were evaluated to determine the potential performance of these materials in the electrochemical production of hydrogen peroxide. Delays in mass losses observed in thermogravimetric studies indicate the improvement of the thermal stability of materials which are related with the highest electrical conductivity (that correspond to hydrochar pyrolyzed at 1000 ºC). High specific surface areas (1097 and 704 m2/g) were also found with hydrochars treated with chemical precursors with values even superior to commercial CB. Results show that all activated hydrochars present electrocatalytic activity towards the production of hydrogen peroxide and that the materials chemically activated with KOH can achieve a 70% of the H2O2 production obtained with commercial CB. Moreover, it was found that the presence of metals in the synthesized materials may promote a Fenton-like reaction, increasing by 40% the generation of hydroxyl radicals with respect to commercial CB. This paramount finding opens the window for the use of this phytoremediation waste to produce sustainable electrode materials for upgraded electrochemical advanced oxidation processes., Se siguió un enfoque de economía circular para convertir residuos de biomasa contaminados con metales (obtenidos de procesos de fitorremediación) para generar materiales de carbón electroactivo para ser utilizados en la producción electroquímica de peróxido de hidrógeno. Los materiales carbonados fueron pretratados mediante carbonización hidrotermal a 200ºC y 130 g suelo mL -1 de agua y posttratados mediante pirólisis a diferentes temperaturas (300ºC, 500ºC y 1000ºC) y utilizando diferentes precursores químicos como KOH o H 3 PO 4 . Estos materiales modificarían los cátodos del papel carbón (CP) para sustituir al comúnmente utilizado negro de carbón (CB), que proviene de los combustibles fósiles. Porosidad, comportamiento termoquímico, conductividad eléctrica, respuesta electrocatalítica y H 2Se evaluaron pruebas de acumulación de O 2 para determinar el desempeño potencial de estos materiales en la producción electroquímica de peróxido de hidrógeno. Los retrasos en las pérdidas de masa observados en los estudios termogravimétricos indican la mejora de la estabilidad térmica de los materiales que se relacionan con la mayor conductividad eléctrica (que corresponden al hidrocarbón pirolizado a 1000 ºC). También se encontraron áreas superficiales específicas altas (1097 y 704 m 2 /g) con hidrocarbonos tratados con precursores químicos con valores incluso superiores al CB comercial. Los resultados muestran que todos los hidrochares activados presentan actividad electrocatalítica hacia la producción de peróxido de hidrógeno y que los materiales químicamente activados con KOH pueden alcanzar un 70% del H 2 O 2producción obtenida con CB comercial. Además, se encontró que la presencia de metales en los materiales sintetizados puede promover una reacción tipo Fenton, aumentando en un 40% la generación de radicales hidroxilo con respecto a los CB comerciales. Este hallazgo primordial abre la ventana para el uso de estos desechos de fitorremediación para producir materiales de electrodos sostenibles para procesos de oxidación avanzada electroquímicos mejorados.

BACKGROUND This work studied the treatment of a synthetic sphalerite acid mine drainage (AMD). The treatment was carried out by means of a previous concentration stage using electrodialysis, followed by electrodeposition using a bioelectrochemical system (BES). RESULTS The best concentration results were obtained when operating the electrodialysis at 8 V and at a diluate/concentrate volume ratio of 3. This treatment yielded a concentrate fraction of about 25% of the volume and a clear fraction of about 75% of the volume. The concentrated fraction was treated in a BES for the electrodeposition of the metal contained. By operating a microbial fuel cell (MFC), the spontaneous reactions took place and, in 2 days, all the Fe3+ was reduced to Fe2+; then, all the Cu2+ was electrodeposited as pure Cu0 in about 8 days. The maximum current density attained in this stage was 0.1 mA cm−2 and the maximum power was 0.05 W cm−2. Then, a subsequent operation of a microbial electrolysis cell (MEC) allowed for the simultaneous recovery of the Fe2+, Ni2+, Zn2+, and Cd2+ as a mixed metal mass. CONCLUSION The electrodialysis yielded a clear effluent representing 75% of the total volume and a concentrated effluent accounting for 25%. It was possible to treat the concentrated effluent in an MFC, recovering pure Cu0 with a net electricity generation. The non-spontaneous metal reductions were subsequently accomplished by means of MEC, the electricity requirements being lower than those in the case of the raw AMD due to the higher mass transfer rate and the reduction of the Ohmic loses. © 2023 Society of Chemical Industry (SCI)., ANTECEDENTES En este trabajo se estudió el tratamiento de un drenaje ácido de mina (DAM) sintético de esfalerita. El tratamiento se realizó mediante una etapa previa de concentración mediante electrodiálisis, seguida de electrodeposición mediante un sistema bioelectroquímico (BES). RESULTADOS Los mejores resultados de concentración se obtuvieron al operar la electrodiálisis a 8 V y a una relación de volumen diluido/concentrado de 3. Este tratamiento produjo una fracción concentrada de aproximadamente el 25% del volumen y una fracción clara de aproximadamente el 75% del volumen. La fracción concentrada se trató en una BES para la electrodeposición del metal contenido. Mediante el funcionamiento de una pila de combustible microbiana (MFC), se produjeron las reacciones espontáneas y, en 2 días, todo el Fe3+ se redujo a Fe2+; a continuación, todo el Cu2+ se electrodepositó como Cu0 puro en unos 8 días. La densidad de corriente máxima alcanzada en esta etapa fue de 0,1 mA cm-2 y la potencia máxima de 0,05 W cm-2. A continuación, una operación posterior de una célula de electrólisis microbiana (MEC) permitió la recuperación simultánea del Fe2+, Ni2+, Zn2+ y Cd2+ como masa metálica mixta. CONCLUSIÓN La electrodiálisis produjo un efluente claro que representaba el 75% del volumen total y un efluente concentrado que representaba el 25%. Fue posible tratar el efluente concentrado en una MFC, recuperando Cu0 puro con una generación neta de electricidad. Las reducciones no espontáneas de metales se realizaron posteriormente mediante MEC, siendo los requerimientos de electricidad menores que en el caso del AMD crudo debido a la mayor tasa de transferencia de masa y a la reducción de las pérdidas óhmicas. 2023 Sociedad de la Industria Química (SCI).

Versión del poster publicada en las X Jornadas Doctorales de la UCLM que tuvieron lugar el 25 de Noviembre de 2022 en el Campus de Albacete

To identify the prevalence of self-reporting of symptoms and access to testing and diagnosis of coronavirus-19 disease (COVID-19), as well as its association with social determinants of health (SDH).Cross-sectional study with a sample of 11 728 men and 12 612 women over the age of 17, based on the National Household Survey 2020. The dependent variables were the self-reporting of symptoms, access to testing, and a positive COVID-19 test. The independent variables were age, educational level, area of residence and geographic area, ethnicity, type of household, income per capita, occupation, and health insurance. Prevalences, bivariate associations, and binomial logistical regression models (odds ratio (OR), and 95% confidence interval (CI95%) were calculated.Of the total individuals included, 16% reported symptoms, 10% a test, and 4.2% a positive COVID-19 test. Inequalities were observed in the reporting of COVID-19 symptoms, with a higher probability in women whose income had fallen (OR: 1.7; CI95%: 1.2-2.4) and unemployed persons (OR: 1.2; CI95%: 1.1-1.4 for men and OR: 1.3; CI95%: 1.5-1.5 for women). In contrast, with respect to access to diagnostic tests, the highest probability was observed in people with higher education (OR: 2.4; CI95%: 1.9-2.9 for men and OR: 2.7; CI95%: 2.2-3.4 for women), whose income was maintained (OR: 1.5; CI95%: 1.3-1.9 for men and OR: 1.7; CI95%: 1.4-2.0 for women) and those in the highest quartile of per capita household income (OR: 2.0; CI95%: 1.6-2.5 for men and OR: 1.6; CI95%: 1.3-2.0 for women). The probability of reporting symptoms and getting tested, and being diagnosed with COVID-19 increased with age for people with health insurance and those living in theThere are inequalities in access to testing and the reporting of COVID-19 symptoms.Identificar a prevalência de sintomas autorreferidos, acesso a testagem e acesso ao diagnóstico da doença do coronavírus de 2019 (COVID-19), bem como sua associação com os determinantes sociais da saúde (DSS).Estudo transversal com amostra de 11 728 homens e 12 612 mulheres com mais de 17 anos, com base na Pesquisa Nacional de Domicílios de 2020. As variáveis dependentes foram sintomas autorreferidos, acesso ao teste e teste positivo para COVID-19. As variáveis independentes foram idade, escolaridade, tipo e local de residência, etnia, tipo de domicílio, renda per capita, atividade e plano de saúde. Foram calculados prevalência, associações bivariadas e modelos de regressão logística binomial (Do total de pessoas incluídas, 16% relataram sintomas; 10%, realização de teste; e 4,2%, um teste positivo para COVID-19. Houve desigualdades no relato de sintomas de COVID-19, com maior probabilidade em mulheres cuja renda havia diminuído (OR: 1,7; IC95%: 1,2-2,4) e que estavam desempregadas (OR: 1,2; IC95%: 1,1 -1,4 para homens e OR: 1,3; IC95%: 1,5-1,5 para mulheres). Em contrapartida, quanto ao acesso a exames diagnósticos, a maior probabilidade foi observada em pessoas com nível superior (OR: 2,4; IC95%: 1,9-2,9 para homens e OR: 2,7; IC95%: 2,2-3,4 para mulheres) cuja renda foi mantida (OR: 1,5; IC95%: 1,3-1,9 para homens e OR: 1,7; IC95%: 1,4- 2,0 para mulheres) e pertencentes ao maior quartil de renda domiciliar per capita (OR: 2,0; IC95%: 1,6-2,5 para homens e OR: 1,6; IC95%: 1,3-2,0 para mulheres). A probabilidade de relatar sintomas, fazer o teste e ser diagnosticado com COVID-19 aumentou com a idade e foi maior nos casos de pessoas que têm plano de saúde e nos de moradores da região dosExistem desigualdades no acesso a testes e na notificação de sintomas de COVID-19.

Along with rapid social development, the use of insecticides and caffeine-containing products increases, a trend that is also reflected in the composition of surface waters. This study is focused on the phototreatment of a surface water containing three neonicotinoids (imidacloprid, thiamethoxam, and clothianidin) and caffeine. Firstly, the radiation absorption of the target pollutants and the effect of the water matrix components were evaluated. It was observed that the maximum absorption peaks appear at wavelengths ranging from 246 to 274 nm, and that the water matrix did not affect the efficiency of the removal of the target pollutants. It was found that the insecticides were efficiently removed after a very short exposure to UV irradiation, while the addition of hydrogen peroxide was needed for an efficient caffeine depletion. The electrical energy per order was estimated, being the lowest energy required (9.5 kWh m−3 order−1) for the depletion of thiamethoxan by indirect photolysis, and a concentration of hydrogen peroxide of 5 mg dm−3. Finally, a preliminary evaluation on the formation of by-products reveals that these compounds play a key role in the evolution of the ecotoxicity of the samples, and that the application of direct photolysis reduces the concentration of these intermediates., Junto con el rápido desarrollo social, aumenta el uso de insecticidas y productos que contienen cafeína, una tendencia que también se refleja en la composición de las aguas superficiales. Este estudio se centra en el fototratamiento de un agua superficial que contiene tres neonicotinoides (imidacloprid, tiametoxam y clotianidina) y cafeína. En primer lugar, se evaluó la absorción de radiación de los contaminantes objetivo y el efecto de los componentes de la matriz del agua. Se observó que los picos máximos de absorción aparecen en longitudes de onda que van desde 246 a 274 nm, y que la matriz de agua no afectó la eficiencia de remoción de los contaminantes objetivo. Se encontró que los insecticidas se eliminaban de manera eficiente después de una exposición muy corta a la radiación ultravioleta, mientras que se necesitaba la adición de peróxido de hidrógeno para un agotamiento eficiente de la cafeína.−3 orden −1 ) para el agotamiento de tiametoxano por fotólisis indirecta, y una concentración de peróxido de hidrógeno de 5 mg dm −3 . Finalmente, una evaluación preliminar sobre la formación de subproductos revela que estos compuestos juegan un papel clave en la evolución de la ecotoxicidad de las muestras, y que la aplicación de fotólisis directa reduce la concentración de estos intermedios.

The aim of this study was to study and model the bioleaching of abandoned mine tailings at different pulp densities 1–20% w/v by using an autochthonous mesophilic microbial culture. Because of the importance of the ferrous-iron oxidation as sub-process on the bioleaching of sulphide mineral ores, the ferrous-iron oxidation process by the autochthonous microbial culture was studied at different ferrous-iron concentrations. A mathematical model fitted to the experimental results and the main kinetic and stoichiometric parameters were determined, being the most relevant the maximum ferrous-iron oxidation rate 5.1 (mmol Fe2+/mmol C·h) and the biomass yield, 0.01 mmol C/mmol Fe2+, values very similar to that of mixed cultured dominated by Leptospirillum strains. This autochthonous culture was used in the bioleaching experiment carried out at different pulp densities, obtaining a maximum metal recovery in the tests carried out at 1% w/v, recovering a 90% of Cd, 60% of Zn, 30% of Cu, 25% Fe and 6% of Pb. Finally, the different leaching mechanisms were modelled by using the pyrite as ore model obtaining a bioleaching rate of 0.316 mmol Fe2+/(L·h) for the direct mechanisms and a bioleaching rate for the indirect and cooperative leaching mechanisms of 0.055 Fe2+/(L·h)., El objetivo de este estudio fue estudiar y modelar la biolixiviación de relaves mineros abandonados a diferentes densidades de pulpa de 1 a 20 % p/v mediante el uso de un cultivo microbiano mesófilo autóctono. Debido a la importancia de la oxidación del hierro ferroso como subproceso en la biolixiviación de minerales sulfurados , se estudió el proceso de oxidación del hierro ferroso por parte del cultivo microbiano autóctono a diferentes concentraciones de hierro ferroso. Se ajustó un modelo matemático a los resultados experimentales y se determinaron los principales parámetros cinéticos y estequiométricos, siendo los más relevantes la velocidad máxima de oxidación del hierro ferroso 5,1 (mmol Fe 2+ /mmol C·h) y el rendimiento de biomasa , 0,01 mmol C/ mmolFe 2+, valores muy similares a los de cultivos mixtos dominados por cepas de Leptospirillum . Este cultivo autóctono se utilizó en el experimento de biolixiviación realizado a diferentes densidades de pulpa, obteniendo una máxima recuperación de metales en los ensayos realizados al 1% p/v, recuperando un 90% de Cd, 60% de Zn, 30% de Cu, 25% Fe y 6% de Pb. Finalmente, se modelaron los diferentes mecanismos de lixiviación utilizando el modelo pirita como mineral obteniendo una tasa de biolixiviación de 0.316 mmol Fe 2+ /(L·h) para los mecanismos directos y una tasa de biolixiviación para los mecanismos de lixiviación indirecta y cooperativa de 0.055 Fe 2 + /(L·h).

This work intends to go a step further in the application of electrochemical technology to produce ozone, by evaluating the production of ozone with a commercial cell registered as CabECO®, which has been previously used to disinfect heavily polluted water in a successful manner, with a view to ascertaining whether this success may be related to the production of ozone. The CabECO® cell is a PEM electrolyzer; that is to say, one in which anode and cathode are connected through a PEM membrane. Since ozone production on the electrolyte is important and depends on the composition of the liquid, attention must be paid to the electrochemical production of scavengers. Dosing of oxygen as microbubbles has a very positive effect on the production of ozone, while temperature regulation is as well considerably important, as the increase in temperature generated by ohmic losses can lead to important decreases in the efficiency of ozone electrogeneration. Rates within the range 0.06–0.60 mg O3 min−1 are observed; this means that the maximum current efficiency reached is as high as 6.11% (considering oxygen as raw matter). These results are extremely promising as compared with other references in the literature, at once they also indicate there is room for further improvements and a long way to prevent the effect of scavengers and increase the efficiency of the process.

This work is focused on the characterization of the production of ozone, hydrogen peroxide and hydroxyl radicals (peroxone) in pressurized undivided electrochemical cells. BDD and MMO electrodes were compared as anodes and RVC, graphite and stainless steel as cathodes. Gauge pressures in the range 2–4 bar were applied. Results demonstrate the complexity in the production of oxidants in an undivided cell, allowing to propose a model of the set of reactions (both electrochemical and in the bulk) occurring in the system. A higher pressure decreases the accumulation of ozone meanwhile hydrogen peroxide production is maximized at intermediate values of pressure. Combining BDD and graphite is the best combination for enhancing the production of hydroxyl radicals for which a negligible influence of pressure was observed. These results would allow to select the proper design to maximize the efficiency in the production of each of the oxidants studied.

Although the first published works on electrodeposition dates from more than one century ago (1905), the uses of this technique in the recovery of metals are attracting an increasing interest from the scientific community in the recent years. Moreover, the intense use of metals in electronics and the necessity to assure a second life of these devices in a context of circular economy, have increased the interest of the scientific community on electrodeposition, with almost 3000 works published per year nowadays. In this review, we aim to revise the most relevant and recent publications in the application of electrodeposition for metal recovery. These contributions have been classified into four main groups of approaches: (1) treatment and reuse of wastewater; (2) use of ionic liquids; (3) use of bio-electrochemical processes (microbial fuel cells and microbial electrolysis cells) and (4) integration of electrodeposition with other processes (bioleaching, adsorption, membrane processes, etc.). This would increase the awareness about the importance of the technology and would serve as a starting point for anyone that aims to start working in the field.

In this work, the production of ozone at mild pH conditions using a commercial electrochemical PEM cell CONDIAPURE Ⓡ is evaluated, at once a phenomenological model is proposed to understand the basis of the processes that occur inside the cell. At these pH conditions, the production of ozone can be explained from the oxidation of water, while the decomposition of ozone is found to be extremely important to explain the global experimental behavior observed. Not only is this decomposition a chemical but also an electrochemically assisted process which, in turn, can be related to the production of other oxidants in the cell which interact with ozone behaving as predators. The model formulated explains and satisfactorily reproduces the influence of the operation mode, the current intensity applied and presence and destruction of organics, with regression coefficients (r2) ranging from 0.88 to 0.99, helping to understand how the production of ozone should be promoted during electrochemical processes.

Resumen: En el contexto de Asociación VACTERL, el diagnóstico prenatal de atresia esofágica concomitante con atresia duodenal es poco común. En el presente artículo se realiza el reporte de un caso con la descripción de los hallazgos ecográficos encontrados a partir semana doce de gestación, con la aparición del signo de doble burbuja intraabdominal compatible con atresia duodenal y una arteria umbilical única; y hacia la semana 31 el hallazgo de imagen anecóica y dilatación esofágica del tercio distal con comunicación con la cámara gástrica en corte longitudinal, representando una atresia esofágica, asociada además a polihidramnios. Desde el momento del nacimiento por examen físico y estudios complementarios, se evidenció además ano imperforado con fístula recto vestibular, arcos costales derechos fusionados y hemivértebras. Por los anteriores hallazgos clínicos y radiológicos, se considera que se trata de una asociación VACTERL; sin embargo, sin alteraciones cardiacas, que es una de las características más frecuentemente encontradas. Se realiza una revisión del estado del arte con respecto a la asociación VACTERL y el diagnóstico prenatal de la atresia esofágica y duodenal. Abstract: In the context of the VACTERL Association, prenatal diagnosis of concomitant esophageal atresia with duodenal atresia is rare. In this article, a case report is described with the description of the ultrasound findings found from week twelve of gestation, with the appearance of the intra-abdominal double bubble sign compatible with duodenal atresia and a single umbilical artery; and towards week 31 the finding of anechoic image and esophageal dilation of the distal-third with communication with the gastric chamber in longitudinal section, representing esophageal atresia, also associated with polyhydramnios. Physical examination and complementary studies from birth showed an imperforate anus with a rectovestibular fistula, and hemivertebrae. Based on the above clinical and radiological findings, it is considered to be a VACTERL association; however, without cardiac abnormalities, which is one of the most frequently found characteristics. A review of the state of the art is carried out with regard to the VACTERL association and the prenatal diagnosis of esophageal and duodenal atresia. Resumo: No contexto da Associação VACTERL, o diagnóstico pré-natal de atrésia do esôfago concomitante com atrésia de duodeno é pouco comum. Neste artigo, é realizado relato de um caso com a descrição dos achados ecográficos encontrados a partir da 12a semana de gestação, com o surgimento do sinal de dupla bolha intra-abdominal compatível com a atrésia duodenal e uma artéria umbilical única; na 3ia semana, o achado de imagem anecoica e dilatação esofágica do rádio distai com comunicação com a câmara gástrica em corte longitudinal, o que representa atrésia esofágica, associada, ainda, a polidrâmnio. Desde o momento do nascimento por exame físico e estudos complementares, é evidenciado ânus imperfurado com fístula retal vestibular, arcos costais direitos fusionados e hemivértebras. A partir dos achados clínicos e radiológicos, é considerado que se trata de uma associação VACTERL; contudo, sem alterações cardíacas, que é uma das características mais frequentemente encontradas. É realizada uma revisão do estado da arte a respeito da associação VACTERL e o diagnóstico pré-natal da atrésia esofágica e duodenal.

In this work, it is evaluated the fixation of carbon dioxide using the alkali generated in the chloralkaline process, as a new way to face the treatment of highly saline wastewater, in which it is aimed not to separate the wastewater into concentrated and diluted streams but to recover value-added products (VAPs) while contributing to minimize the carbon fingerprint of other processes. The electrolytic process is combined with a reactive absorption and with a crystallization, demonstrating the formation of pure nahcolite, hypochlorite (or chlorine) and hydrogen from the waste. Carbon dioxide is captured with a current efficiency over 90% and the energy required is around 0.65 kWh kg

This work reports the use of a special PEM-electrolyzer equipped with diamond anodes for the highly-efficient disinfection of water preventing the formation of chlorates and perchlorates. The cell is a MIKROZON® cell manufactured by CONDIAS (Itzehoe, Germany) with a very short hydraulic residence time (0.008 s for 90 L h−1, which is the maximum allowable flowrate) and a polymer exchange membrane electrolyte that separates the anode and cathode into a membrane-electrode assembly. This cell can avoid the formation of significant concentrations of chlorates because of the very short contact time between the water and the electrode that prevents the oxidation of hypochlorite by hydroxyl radicals. In this paper, we report tests in which we demonstrate this outstanding performance even in the worst conditions (low flowrate) and we also explain the differences observed in the operation in continuous and discontinuous mode with the same water.

This work focuses on disinfection of water using electrolysis with diamond coatings avoiding or minimizing the formation of hazardous chlorates and perchlorates using a special type of commercial cells designed by CONDIAS (Itzehoe, Germany) in two different sizes: the CabECO and the MIKROZON cells. In these cells, the electrolyte that separates the anode and cathode is a proton exchange membrane. This helps to minimize the production of perchlorate and this behavior is enhanced in the smallest cell for which the very low contact times between the electrodes and the water allows to avoid the production of perchlorates when operating in a single-pass mode, which becomes a really remarkable point. In this paper, we report tests in which we demonstrate this outstanding performance and we also explain the differences observed in the two cells operating with the same water.

The present work deals with the use of ultrafiltration as a pre-concentration stage in the electrochemical degradation of a non-polar organochlorine compound (oxyfluorfen) with boron-doped diamond (BDD) anodes. The first stage of the work consisted in evaluating the performance of a pilot scale ultrafiltration unit to concentrate a solution of a commercial formulation of oxyfluorfen (Barre®) at total recirculation mode. The ultrafiltration membrane exhibited a total rejection of oxyfluorfen, around 70% rejection of TOC and a permeate flux of 285.1 L h−1 m−2 at 4 bar and 25 °C. The rejection of oxyfluorfen is higher than expected due to the presence of surfactant compounds in the commercial formulation selected, which promotes a mechanism of micellar enhanced ultrafiltration. Next, a discontinuous ultrafiltration test was performed, maintaining this high rejection of oxyfluorfen and observing a limited contribution of fouling mechanisms, according to the adjustment of the data to fouling models. Regarding the electrochemical oxidation of the concentrate with BDD anodes, it was observed an increase in the specific power consumption from 590 kWh kg−1 for the raw solution to 882 kWh kg−1 for the concentrate. This unexpected result can be explained due to the limited rejection of the soluble fraction in the ultrafiltration stage, what produced a lower concurrence of oxidants in the electrochemical oxidation step. According to these results, it can be stated that it is worth using ultrafiltration as a concentration stage for commercial formulations of non-polar organochlorines with both high rejection and flux, although it should be combined with degradation technologies different from electrochemical oxidation.

The improvement in the treatment efficiency of diluted effluents is one of the great challenges faced by electrochemical technology nowadays. In the present work, it is aimed to develop an electrochemical cell for the simultaneous concentration and degradation of ionic organic pollutants. This combined cell (so called EDEO device) integrates the concentration of the organic by electrodialysis (ED) with its electro-oxidation (EO). For the particular case of the 2,4-dichlorophenoxyacetic acid (2,4-D), the performance of the cell has been tested with two anode materials (boron-doped diamond, BDD and mixed mineral oxides, MMO) and with two supporting electrolytes in order to explore four combinations that are expected to cover a wide range of possible actual scenarios. Results demonstrate that the combined EDEO process exhibits a degradation rate and a mineralization current efficiency markedly higher than the equivalent EO device when working with MMO anodes, either with NaCl or with Na2SO4. It was checked that the use of a BDD anode clearly increases the efficiency and the rate of the treatment due to the formation of strong oxidants. In this case, the effect of working with the combined EDEO in the rate of 2,4-D degradation is negligible because the 2,4-D transport rate becomes comparable to the degradation rate, being the combined process unable to generate a concentration greater than that accounted in the single EO device.

In previous works, a low-cost predisinfection column that combined coagulation-flocculation and GAC filtration was proposed for combination with electrodisinfection in the successful treatment of highly faecal polluted surface water. In this work, this column is adapted for the treatment of pore water by transforming the coagulation chamber into a chemical reactor with lime and replacing the GAC of the filter with ion exchange resins. This adapted system can soften water, remove nitrate and condition water for very efficient electrochemical disinfection, where 4 logs and 3 logs in the removal of E. coli and P. aeruginosa, respectively, were reached using commercial electrochemical cells, i.e., CabECO ® or MIKROZON®. The availability and low cost of the technology are strong points for usage in poor areas of developing countries., En trabajos anteriores, se propuso una columna de predesinfección de bajo costo que combinaba coagulación-floculación y filtración GAC para combinarla con electrodesinfección en el tratamiento exitoso de aguas superficiales altamente contaminadas con heces. En este trabajo se adapta esta columna para el tratamiento de agua intersticial transformando la cámara de coagulación en un reactor químico con cal y reemplazando el GAC del filtro por resinas de intercambio iónico . Este sistema adaptado puede ablandar el agua, eliminar el nitrato y acondicionar el agua para una desinfección electroquímica muy eficiente, donde se alcanzaron 4 logs y 3 logs en la eliminación de E. coli y P. aeruginosa , respectivamente, usando celdas electroquímicas comerciales., es decir, CabECO® o MIKROZON®. La disponibilidad y el bajo costo de la tecnología son puntos fuertes para su uso en áreas pobres de los países en desarrollo.

Esta nota técnica brinda una visión general de la arboricultura en América Latina, abordando su evolución, certificaciones reconocidas, la industria de la arboricultura, disponibilidad de equipos, limitaciones, desafíos y estrategias. La arboricultura en América Latina tiene características propias que deben ser consideradas para poder avanzar y desarrollarse. Esta nota técnica resume la discusión realizada el 3 de octubre de 2021, en el XXIV Congresso Brasileiro de Arborização Urbana y III Congresso Internacional de Arborização Urbana.

In this work, it is evaluated the fixation of carbon dioxide using the alkali generated in the chloralkaline process, as a new way to face the treatment of highly saline wastewater, in which it is aimed not to separate the wastewater into concentrated and diluted streams but to recover value-added products (VAPs) while contributing to minimize the carbon fingerprint of other processes. The electrolytic process is combined with a reactive absorption and with a crystallization, demonstrating the formation of pure nahcolite, hypochlorite (or chlorine) and hydrogen from the waste. Carbon dioxide is captured with a current efficiency over 90% and the energy required is around 0.65 kWh kg−1, which is very promising from the view point of sustainability, considering that the system can be easily powered with green energies.

In this work, H2O2 is electrogenerated in the cathodic compartment of a divided filter-press cell with a carbon cloth in the configuration of a gas diffusion electrode using air as the oxygen source. The effect of Teflon content was studied, and it was found that the appropriate content is within the range 10–20%. The production was greatly enhanced after the air-brushing deposition (and subsequent annealing) of simply 0.5 mg cm–2 of carbon black. Higher additions clogged the pores and as a result were counterproductive in terms of H2O2 generation. At a current density of 25 mA cm–2, the production rate was 15 mg of H2O2 h–1 cm–2 with a current efficiency close to 100%. Production rate increased with current density up to more than 40 mg of H2O2 h–1 cm–2 at 87.5 mA cm–2. The good performance and ease of preparation of this electrode make it an interesting alternative to generate hydrogen peroxide for electro-Fenton processes.

La incidencia de cáncer durante la gestación es de 1: 1000 a 2000 embarazos, siendo los más frecuentes el de cérvix, mama, ovario, melanoma, tiroides, colon y hematológicos como linfoma y leucemia. A pesar de ser una entidad poco frecuente en el embarazo, se ha visto una tendencia a aumentar en los últimos años debido al incremento progresivo de la edad materna en el momento de la concepción.El carcinoma gástrico es una patología aún menos frecuente, siendo su incidencia durante la gestación de aproximadamente 0.016% a 0.026% en las series de casos de Japón, país con la mayor prevalencia de enfermedad. La cirugía es el tratamiento oncológico menos controversial durante la gestación. En los últimos años, ha cobrado importancia la quimioterapia adyuvante con antineoplásicos de tipo antimetabolito como el 5 fluoracilo (5 – FU), medicamento que ha demostrado mejoría de la supervivencia en pacientes gestantes con adenocarcinoma gástrico. Desafortunadamente, el 96.7% de los casos son diagnosticados en estadíos avanzados, pues su presentación clínica suele confundirse con las manifestaciones propias de la primera mitad de la gestación como son las nauseas y el vomito. Presentamos dos casos clinicos, el de una gestante de 34 años con embarazo de 19 semanas y 3 días al momento del diagnóstico de un carcinoma gástrico Bormann III, llevada a laparotomía con intención curativa a las 21 semanas con hallazgo intraoperatorio de enfermedad metastásica avanzada y tumor ovárico izquierdo sugestivo de tumor de Krukenberg, a quien se le inicia a las 23 semanas quimioterapia paliativa con esquema FOLFIRI el cual recibió hasta la finalización de la gestación a las 33 semanas por restricción del crecimiento intrauterino y posteriormente durante el puerperio; y el de una gestante de 31 años con embarazo de 26 semanas y 6 días quien se ingresa para estudio de emesis persistente durante la gestación con confirmación diagnóstica de adenocarcinoma gástrico Bormann III asociado a Restricción del crecimiento intrauterino que fue llevada a cesárea a las 34 semanas y en el puerperio a gastrectomía total con vaciamiento ganglionar del area celiaca y reconstrucción en Y de Roux.El objetivo de realizar estos reportes surge de la carencia de guias de manejo respecto a dicha entidad durante la gestación debido a la poca frecuencia de presentación de la misma. Es frecuente encontrar discrepancias entre los conceptos en cuanto a conductas médicas se refiere. Disponemos de reportes y series de casos que orientan el manejo hacia un enfoque interdisciplinario dirigido a sopesar los riesgos y beneficios derivados de implementar o no un tratamiento durante la gestación siendo pocos los casos exitosos reportados en la literatura.

This work focuses on the evaluation of the electrochemical dewatering of sludge obtained in the coagulation of wastes polluted with oxyfluorfen. To do this, sludge samples were treated, aiming not only to reduce the sludge volume, but also to facilitate the degradation of oxyfluorfen contained in the cake via electrolysis with a boron-doped diamond anode. Results show that water can be effectively recovered through three sequential stages. First, a gravity-driven stage, that can recover around 60% of initial volume and where no oxyfluorfen is dragged. Then, a second stage that involves the application of pressure and which accounts for the recuperation of an additional 25% of the total volume of the water removed and in which oxyfluorfen also remained in the cake. Finally, an electrochemical stage, which involves the application of electricity with increasing electric fields (1.0, 2.0, 4.0, and 16.0 V cm−1), accounting for the recovery of the rest of water released and where an electrolytic degradation of oxyfluorfen is obtained, whose extension depends on the electrode configuration used in the electro-dewatering cell. This electrode configuration also influences the retention or loss of oxyfluorfen from the cake, being the optimum choice the placement of the cathode downstream, next to the outlet of the dewatering cell.

This work focusses on the production of hydrogen peroxide and in the removal of bromacil by the electro-Fenton process using two different electrochemical cells: mixed tank cell (MTC) and flow-through cell (FTC). Both cells use boron doped diamond (BDD) as anode and carbon felt as cathode to promote the formation of hydrogen peroxide. In the case of the MTC, two surface area ratios, Acathode/Aanode, have been used. Results show that the H2O2 produced by MTC and FTCPSC increases with the time until a stabilization state. For the FTCPSC, the average hydrogen peroxide concentration produced increases progressively with the current, while for MTC the maximum values are found in applying very low current densities. In addition, the FTCPSC provides higher concentrations of hydrogen peroxide for the same current density applied. Regarding the MTC, it can be stated that the higher the area of the cathode, the higher is the amount of H2O2 produced and the lower is the cell voltage (because of a more efficient current lines distribution). The initial oxidation of bromacil is very efficiently attained being rapidly depleted from wastewater. However, the higher production of hydrogen peroxide obtained by the FTCPSC cell does not reflect on a better performance of the electro-Fenton process. Thus, bromacil is better mineralized using the MTC cell with the lowest cathode area. This observation has been explained because larger concentrations of produced hydrogen peroxide seems to benefit the oxidation of intermediates and not the mineralization.

This work focuses on the scale-up of an integrated electrodisinfection-electrocoagulation (ED-EC) process, especially suited for the reclamation of actual urban treated wastewater, equipped with Boron Doped Diamond (BDD) anodes and iron bipolar electrodes. The system operates in continuous mode and in the prototype the anode area was increased three times (anodic oxidation) and the bipolar electrode area fifteen times (electrocoagulation) with respect to the system used at bench scale. Results show that it is possible to attain the complete and simultaneous disinfection and turbidity removal by applying current densities within the range 5–10 A m−2. Free and combined chlorine species were electrogenerated from the chloride contained in the effluents (no reagents were added) being these species responsible for the removal of microorganisms. Likewise, iron coagulant species coming from the electro-dissolution of the anodic side of bipolar electrodes promote turbidity removal. In the scaled-up prototype, a more efficient turbidity removal was achieved, because of the increase in the bipolar electrode area. Finally, it was probed that for electric charges below 0.07 kAh m−3 the reclamation of urban treated wastewater could be reached, avoiding the formation of hazardous chlorates and perchlorates even at current densities higher than 7 A m−2.

In this work, a new strategy for the treatment of wastes polluted with micelles is evaluated. It consists on the concentration of the pollutant by electrocoagulation, the pre-treatment of the concentrated sludge with US and the later application of an electrolytic oxidation. As it is well-known that the electrolytic treatment of diluted solutions generally fits well a first-order kinetic, this concentration is expected to lead to a more efficient process. This approach has been studied using oxyfluorfen polluted wastes. Electrocoagulation has been carried out for the concentration of a wastewater containing oxyfluorfen reducing its volume from 50.00 to 1.39 L. Once obtained the small volume of concentrated liquid waste, several treatments have been applied such as Ultrasonic irradiation or heat followed by electrooxidation. Results show that application of US has a very positive influence on the performance, in particular LF-US. Application time is also an important parameter and heating has a negative effect on results because iron hydroxide flocs compress and seal the pollutant inside making more difficult their destruction by the direct and indirect oxidation reactions.

This work presents the development of the electrodialysis/electro-oxidation (EDEO) technology, assessing the role of the pollutant and the modelling of the system in order to look for the key aspects for the development of the technology. According to the results obtained, it can be concluded that electrodialysis can be properly used to concentrate clopyralid, having the selected ionic exchange membranes (AMX) an adsorption capacity of 1.64 ± 0.26 mg cm−2. Moreover, it was observed that BDD anodes exhibit a higher degradation and mineralization current efficiencies than MMO when using electro-oxidation (EO). The role of the supporting electrolyte was also assessed, observing a slight better performance of BDD with sulphate (maximum mineralization current efficiency of 80%) and a much superior degradation efficiency with chloride when selecting MMO as anode material. Regarding the EDEO technology, it was checked that this process only overcomes the performance of EO when using MMO anodes, a result that is explained by the ratio between degradation and transport rates. Finally, a simple model was presented and successfully used to predict the degradation rate constants and to simulate the performance of EDEO under different scenarios. These simulations confirm that the transport rate needs to overcome the degradation rate in order to assure a better performance of the EDEO system compared to the conventional EO. Moreover, the simulations explain the results obtained in the present and previous works revealing the key for a further development of the EDEO technology in the future.

Digital, Background: Two glucagon-like peptide-1 (GLP-1) receptor agonists reduced renal outcomes in people with type 2 diabetes at risk for cardiovascular disease. We assessed the long-term effect of the GLP-1 receptor agonist dulaglutide on renal outcomes in an exploratory analysis of the REWIND trial of the effect of dulaglutide on cardiovascular disease. Methods: REWIND was a multicentre, randomised, double-blind, placebo-controlled trial at 371 sites in 24 countries. Men and women aged at least 50 years with type 2 diabetes who had either a previous cardiovascular event or cardiovascular risk factors were randomly assigned (1:1) to either weekly subcutaneous injection of dulaglutide (1·5 mg) or placebo and followed up at least every 6 months for outcomes. Urinary albumin-to-creatinine ratios (UACRs) and estimated glomerular filtration rates (eGFRs) were estimated from urine and serum values measured in local laboratories every 12 months. The primary outcome (first occurrence of the composite endpoint of non-fatal myocardial infarction, non-fatal stroke, or death from cardiovascular causes), secondary outcomes (including a composite microvascular outcome), and safety outcomes of this trial have been reported elsewhere. In this exploratory analysis, we investigate the renal component of the composite microvascular outcome, defined as the first occurrence of new macroalbuminuria (UACR >33·9 mg/mmol), a sustained decline in eGFR of 30% or more from baseline, or chronic renal replacement therapy. Analyses were by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT01394952. Findings: Between Aug 18, 2011, and Aug 14, 2013, 9901 participants were enrolled and randomly assigned to receive dulaglutide (n=4949) or placebo (n=4952). At baseline, 791 (7·9%) had macroalbuminuria and mean eGFR was 76·9 mL/min per 1·73 m2 (SD 22·7). During a median follow-up of 5·4 years (IQR 5·1-5·9) comprising 51 820 person-years, the renal outcome developed in 848 (17·1%) participants at an incidence rate of 3·5 per 100 person-years in the dulaglutide group and in 970 (19·6%) participants at an incidence rate of 4·1 per 100 person-years in the placebo group (hazard ratio [HR] 0·85, 95% CI 0·77-0·93; p=0·0004). The clearest effect was for new macroalbuminuria (HR 0·77, 95% CI 0·68-0·87; p, Ciencias Médicas y de la Salud

Digital, Background Three different glucagon-like peptide-1 (GLP-1) receptor agonists reduce cardiovascular outcomes in people with type 2 diabetes at high cardiovascular risk with high glycated haemoglobin A1c (HbA1c) concentrations. We assessed the effect of the GLP-1 receptor agonist dulaglutide on major adverse cardiovascular events when added to the existing antihyperglycaemic regimens of individuals with type 2 diabetes with and without previous cardiovascular disease and a wide range of glycaemic control. Methods This multicentre, randomised, double-blind, placebo-controlled trial was done at 371 sites in 24 countries. Men and women aged at least 50 years with type 2 diabetes who had either a previous cardiovascular event or cardiovascular risk factors were randomly assigned (1:1) to either weekly subcutaneous injection of dulaglutide (1·5 mg) or placebo. Randomisation was done by a computer-generated random code with stratification by site. All investigators and participants were masked to treatment assignment. Participants were followed up at least every 6 months for incident cardiovascular and other serious clinical outcomes. The primary outcome was the first occurrence of the composite endpoint of non-fatal myocardial infarction, non-fatal stroke, or death from cardiovascular causes (including unknown causes), which was assessed in the intention-to-treat population. This study is registered with ClinicalTrials.gov, number NCT01394952. Findings Between Aug 18, 2011, and Aug 14, 2013, 9901 participants (mean age 66·2 years [SD 6·5], median HbA1c 7·2% [IQR 6·6–8·1], 4589 [46·3%] women) were enrolled and randomly assigned to receive dulaglutide (n=4949) or placebo (n=4952). During a median follow-up of 5·4 years (IQR 5·1–5·9), the primary composite outcome occurred in 594 (12·0%) participants at an incidence rate of 2·4 per 100 person-years in the dulaglutide group and in 663 (13·4%) participants at an incidence rate of 2·7 per 100 person-years in the placebo group (hazard ratio [HR] 0·88, 95% CI 0·79–0·99; p=0·026). All-cause mortality did not differ between groups (536 [10·8%] in the dulaglutide group vs 592 [12·0%] in the placebo group; HR 0·90, 95% CI 0·80–1·01; p=0·067). 2347 (47·4%) participants assigned to dulaglutide reported a gastrointestinal adverse event during follow-up compared with 1687 (34·1%) participants assigned to placebo (p, Ciencias Médicas y de la Salud

This work presents a laboratory to help chemical-engineering students understand the basic concepts of corrosion. This laboratory has been performed since academic year 2011–2012 in the framework of the subject “Design of equipment and installations” for the third year of the Chemical Engineering Degree of the University of Castilla–La Mancha (Spain). It is based on calculating the corrosion rates of six different samples in order to evaluate the effects of the corrosion environment, the material of the sample, and the application of corrosion-prevention methods. The performance of the laboratory to enhance the teaching–learning methodology was evaluated by asking the students to answer a test before and after completing the laboratory. The results show that the laboratory improves the understanding of the students and also their confidence in their answers, although room for improvement was found in relation to the application of corrosion-prevention methods, for which corrective actions are proposed.

This work focuses on the electrochemical production of ozone at acidic pHs, evaluating the influence of the salts in the electrolyte, temperature and pressure on the efficiency of its production. Results demonstrate that electrolysis with electrolytes containing perchlorate salts allow obtaining higher concentrations of ozone than electrolytes containing sulfates. Adding to that, the increase in the operation pressure and the decrease in temperature have a positive effect on the production of ozone. This indicates that not only the oxidation of water, but also the oxidation of oxygen is important to explain the electrochemical production of ozone. A simple model considering all these processes is formulated and validated with the experimental results that allow explaining the fundamentals of ozone production in acidic conditions.

Chlorine dioxide is one of the most interesting oxidants because it combines a strong capacity of oxidation with low formation of hazardous byproducts such as chlorinated organics during its application. Because of that, it is widely used in disinfection of drinking water and, currently, it is aimed to be used in the disinfection of surfaces or buildings. Although it is usually produced by the chemical interaction of chlorite with hypochlorite/chlorine or hydrochloric acid, one interesting alternative for its production is the combination in strongly acidic media of chlorate and hydrogen peroxide. Both compounds are known to be efficiently manufactured with electrochemical technology, opening the possibility of a complete electrochemical process to produce this important oxidant. This review summarizes the recent progress in the electrochemical production of the two raw materials, as well as the complete electrochemical production of chlorine dioxide, not only paying attention to the scientific literature but, most importantly, to recent patents, trying to see in which technology readiness level are each of the technologies and what are the elements of the value chain required for a complete implementation of the technology.

Ozone is a rather attractive oxidant, it is very efficient in the oxidation of pollutants and in the killing of pathogens and does not generate any hazardous waste during its use. Its generation has been constantly sought in an effective way, focusing on obtaining high concentrations of ozone at the lowest possible cost. Recently, electrochemical production of ozone show advantages over conventional corona discharge generation, since this technology do not need very high voltages, feeding oxygen or pure air or dissolving the ozone into wastewater to be treated. However, it is still at early development stage and there is still a long way to reach the high technology readiness levels needed to complete its value chain. Equipment considerations and operation conditions are the key points that need to be understood in order to increase efficiently. Recent novelties in the state of the art of research are summarized in this work.

Electrocoagulation (EC) presents operational advantages over chemical coagulation, including no requirement for the addition of chemicals. This work compares the performance of electrocoagulation in two stages of the urban water cycle: drinking water production and wastewater regeneration. A case study focussed on the treatment of actual effluents from different locations in the centre of Spain is performed. It was observed that electrocoagulation with aluminium anodes is an efficient technique to remove turbidity and total organic carbon (TOC) from surface water and to deplete turbidity and Escherichia coli (E. coli) from urban treated wastewater (taken from the outlet of an urban wastewater treatment facility, WWTF). Although electrocoagulation can be applied to the treatment of both effluents, the technique is more efficient in the case of the production of drinking water from surface sources. This behaviour is related to the nature of the natural organic matters (NOM) present in both effluents., La electrocoagulación (EC) presenta ventajas operativas sobre la coagulación química, incluida la ausencia de requisitos para la adición de productos químicos. Este trabajo compara el desempeño de la electrocoagulación en dos etapas del ciclo del agua urbana: producción de agua potable y regeneración de aguas residuales. Se realiza un estudio de caso centrado en el tratamiento de efluentes reales de diferentes localizaciones del centro de España. Se observó que la electrocoagulación con ánodos de aluminio es una técnica eficaz para eliminar la turbidez y el carbono orgánico total (COT) de las aguas superficiales y para reducir la turbidez y Escherichia coli ( E. coli) de aguas residuales urbanas tratadas (extraídas de la salida de una planta de tratamiento de aguas residuales urbanas, WWTF). Aunque la electrocoagulación puede aplicarse al tratamiento de ambos efluentes, la técnica es más eficaz en el caso de la producción de agua potable a partir de fuentes superficiales. Este comportamiento está relacionado con la naturaleza de las materias orgánicas naturales (NOM) presentes en ambos efluentes.

This work focuses on disinfection of water using electrolysis with boron doped diamond (BDD) coatings and faces this challenge by comparing the performance of two different cells manufactured by CONDIAS GmbH (Izehoe, Germany): CONDIACELL® ECWP and CabECO cells. They are both equipped with diamond electrodes, but the mechanical design is completely different, varying not only by geometry but also by the flow conditions. ECWP is a flow-through cell with perforated electrodes while the CabECO cell is a zero-gap cell with a proton exchange membrane as a solid polymer electrolyte (SPE) separating the anode and cathode. At 0.02 Ah dm−3 both cells attain around 3–5 logs pathogen removal, but design and sizing parameters give an advantage to the CabECO: it can minimize the production of chlorates and perchlorates when operating in a single-pass mode, which becomes a really remarkable point. In this paper, we report tests in which we demonstrate this outstanding performance and we also explain the differences observed in the two cells operating with the same water.

In this work, the CabECO® electrochemical cell is evaluated in continuous mode for the disinfection of highly fecal-polluted surface water. Results show that this cell is very efficient in the removal of Total Coliforms and Pseudomonas Aeruginosa and it can achieve decays up to 4-log units when treating 90 L h−1 with a single cell (only 24 cm2 of diamond electrode). Efficiency of the disinfection depends on the current charge applied and neither organo-chlorinated species nor perchlorates are formed at the conditions evaluated. A two-log unit sterilization can be attained with the technology, which shows worse prospects for this application than for disinfection. Electrode’s fouling caused by strongly polluted water may diminish the disinfection efficiency and it can even prevent the use of this technology in those cases.