Selective recovery of antimony from Sb-bearing copper concentrates by integration of alkaline sulphide leaching solutions and microwave-assisted heating and leaching: A new sustainable processing route.

The technical feasibility of leaching antimony from an antimony-bearing copper sulphide concentrate, using alkaline sulphide solutions and microwave-assisted and non-assisted heating technology, is investigated at a laboratory scale. The leaching test examines the influence of selective leaching reagent (Na2S and NaOH) concentrations, solid/liquid ratio, and temperature. The results indicate that antimony dissolution is highly selective (e.g. only Sb and As are leached), depending on the concentrations of leaching reagents and the leaching temperature. The influence of temperature on the mineral's dissolution, in the range 25-140 °C, is analysed from a thermochemical point of view using equilibrium databases. Under the optimal conditions: leaching agent: 250 g/L Na2S, 60 g/L NaOH, 2 h, 140 °C, with microwave assisted, the leaching efficiency of Sb reached 95.7 %. The antimony content in the copper concentrate is successfully reduced from 1.1 wt% to <0.2 wt% Sb, making it suitable for copper concentrate metallurgical processing. The study demonstrates that increasing temperature and NaOH/Na2S concentrations collectively enhance leaching efficiency, with a statistical significance, reducing both leaching time and the required temperature, compared to non-microwave-assisted leaching. Furthermore, it is established that excess free hydrogen sulphide ions ensure the efficient dissolution of the main impurities associated with penalties, such as antimony and arsenic, with limited copper and iron dissolution from the copper concentrate, predominantly chalcopyrite. Finally, an integrated hydrometallurgical process flowsheet for antimony removal and recovery from a sulphide copper concentrate is proposed.

Evaluation of enhanced nanofiltration membranes for improving magnesium recovery schemes from seawater/brine: Integrating experimental performing data with a techno-economic assessment.

The global demand for valuable metals and minerals necessitates the exploration of alternative, sustainable approaches to mineral recovery. Seawater mining has emerged as a promising option, offering a vast reserve of minerals and an environmentally friendly alternative to land-based mining. Among the various techniques, Nanofiltration (NF) has gained significant attention as a preliminary treatment step in Minimum Liquid Discharge (MLD) and Zero Liquid Discharge (ZLD) schemes. This study focused on the potential of two underexplored commercial polyamide based NF membranes, Synder NFX and Vontron VNF1, with enhanced divalent over monovalent separation factors, in optimizing the extraction of magnesium hydroxide (Mg(OH)2) from seawater and seawater reverse osmosis (SWRO) brines. The research encompassed a thorough characterization of the membranes utilizing advanced physic-chemical analytical techniques, followed by rigorous experimental assessments using synthetic seawater and SWRO brine in concentration configuration. The findings highlighted the superior selectivity of NFX for magnesium recovery from SWRO brine and the promising concentration factors of VNF1 for seawater treatment. Cross-validation of experimental data with a mathematical model demonstrated the model's reliability as a process design tool in predicting membrane performance. A comprehensive techno-economic evaluation demonstrates the potential of NFX, operating optimally at 23 bar pressure and 70% permeate recovery rate, to yield an estimated annual revenue of 5.683 M€/yr through Mg(OH)2 production from SWRO brine for a plant with a nominal capacity of 0.8 Mm3/y. This research shed light on the promising role of NF membranes in enhancing mineral recovery taking benefit of their separation factors and emphasizes the economic viability of leveraging NF technology for maximizing magnesium recovery from seawater and SWRO brines.

Selective recovery of boron, cobalt, gallium and germanium from seawater solar saltworks brines using N-methylglucamine sorbents: Column operation performance.

The European Union (EU) identified a list of Critical Raw Materials (CRMs) crucial for its economy, aiming to find alternative sources. Seawater is a promising option as it contains almost all elements, although most at low concentrations. However, to the present, the CRMs' recovery from seawater is technically and economically unfeasible. Other alternatives to implement sea mining might be preferred, such as reverse osmosis brines or saltworks bitterns (after sodium chloride crystallisation). The CRMs' extraction in a selective way can be achieved using highly selective recovery processes, such as chelating sorbents. This study focuses on extracting Trace Elements (TEs) from solar saltworks brines, including boron, cobalt, gallium and germanium, using commercial N-methylglucamine sorbents (S108, CRB03, CRB05). The application of these sorbents has shown potential for boron recovery, but their selectivity for cobalt, gallium, and germanium requires further investigation. This research aims to assess these sorbents' kinetics and column mode performance for TEs recovery from synthetic bitterns. Boron and germanium were rapidly sorbed, reaching equilibrium (>90 %) within 1 h, except for S108, which took 2 h. In column mode, 20-25 pore volumes of bittern were treated to remove boron and germanium, but competition from other elements reduced treatment capacity. An acidic elution (1 M hydrochloric acid) allowed to elute them (>90 %), reaching concentration factors for germanium and boron of 35 and 11, respectively, while cobalt and gallium had less affinity for the sorbents. In addition, the experiments performed were fitted by a mass transfer model to determine the equilibrium constants and selectivities. Therefore, bittern mining has been proven as a secondary/alternative source to obtain CRMs, which can lead the EU to a position in which its dependence on other countries to obtain these raw materials would be decreased.

Factores relacionados con las técnicas de reproducción asistida y su repercusión en el neonato / Factors associated with assisted reproduction technologies and neonatal outcomes

Introducción: Las técnicas de reproducción asistida (TRA) pueden estar asociadas a complicaciones obstétricas y perinatales, incluido un aumento de malformaciones. El objetivo de este estudio fue comparar los resultados obstétricos y neonatales de las gestaciones únicas y múltiples por fertilización in vitro (FIV) e ICSI (intra cytoplasmatic sperm injection`inyección intracitoplásmica de espermatozoides) con las gestaciones espontáneas. Pacientes y métodos: Estudio de casos y controles de los recién nacidos de embarazos obtenidos con las técnicas FIV e ICSI en el Hospital Clínic de Barcelona entre enero de 1999 y diciembre de 2005. Se recogieron 499 casos y 432 controles. Resultados: El grupo estudio (gestaciones por FIV e ICSI) tiene más prematuridad (definida como gestación inferior a 37 semanas), menor peso al nacer (definido como peso inferior al P10 para su edad gestacional y sexo), más embarazos múltiples, madres de mayor edad y más complicaciones obstétricas, como amenaza de aborto y prematuridad, enfermedad placentaria, hipertensión arterial, diabetes gestacional y hemorragias. Los recién nacidos muestran una enfermedad y una mortalidad similar con más ingresos. Al analizar sólo las gestaciones únicas, en el grupo estudio destaca más prematuridad y bajo peso al nacer, más complicaciones obstétricas, más enfermedades neonatales relacionadas con la prematuridad y el aumento de malformaciones (el 9,7 frente al 4,3%, respectivamente; p=0,046). Al analizar sólo las gestaciones múltiples no hay diferencia en prematuridad ni en peso al nacer, ni en número de malformaciones, pero el grupo estudio tiene más complicaciones obstétricas, como amenaza de aborto, diabetes gestacional y toxemia. Aunque la técnica ICSI tiende a asociarse a más malformaciones, no hay diferencia estadística significativa (el 11,0 frente al 5,6%, respectivamente; p=0,099) y el estudio multivariante no muestra una influencia independiente. Conclusiones: Las TRA (FIV e ICSI) se asocian con más prematuridad, bajo peso al nacer y aumento de enfermedad obstétrica. Las gestaciones únicas por FIV e ICSI muestran aumento de malformaciones si bien el riesgo de que éstas aparezcan no depende de las técnicas utilizadas (AU)

Introduction: Assisted reproduction technologies can be associated with poor obstetric and perinatal outcomes and an increase in congenital malformations. The objective of this study was to compare obstetric and perinatal outcome of single and multiple pregnancies conceived by IVF (in vitro fertilization) or ICSI (intracytoplasmic sperm injection) with spontaneous pregnancies. Patients and methods: A case-control study was conducted on the newborns conceived by IVF and ICSI in Hospital Clínic Barcelona between January 1999 and December 2005. There were 499 cases reported and 432 controls. Results: The case group had an increased risk of preterm birth (<37 weeks) and low birth weight (<10th percentile in relation to gestational age and sex). The case group had more multiple births, higher maternal age, more obstetric complications, such as abortion risk, preterm delivery, placental complications, hypertension, gestational diabetes, maternal haemorrhage. There were no significant differences in perinatal outcome, although newborn conceived by IFV/ICSI were admitted to hospital more. In single pregnancies, the case group showed more preterm deliveries and low birth weight, more obstetric complications and more congenital malformations (9.7% vs. 4.3% P=0.046). In multiple pregnancies there were no significant differences in perinatal outcome and incidence of malformations. The case group had a higher incidence of obstetric complications, such as abortion risk, gestational diabetes and hypertension. Although ICSI was associated to more malformations (11.0% vs. 5.6%), there was no significant statistical difference (P=0.099) and the multivariate analysis did not show an independent influence on risk of malformation. Conclusion: IFV/ICSI techniques have an increased risk of premature delivery, low birth weight, and poorer obstetric outcomes. Single pregnancies tend to have more congenital malformations. The risk of malformations is not associated with a specific technique (AU)

Sarcoma intimal de arteria pulmonar: una causa infrecuente de hipertensión pulmonar / Intimal sarcoma of the pulmonary artery: a rare cause of pulmonary hypertension

El sarcoma intimal de la arteria pulmonar es un tumor infrecuente que habitualmente se diagnostica en el acto quirúrgico o la autopsia. Por lo general crece regionalmente, con poca capacidad de metastatizar. El diagnóstico es difícil y con frecuencia se retrasa debido a la naturaleza inespecífica de los síntomas. Su baja frecuencia y el crecimiento insidioso hacen que a menudo se confunda con una tromboembolia pulmonar, y por ello se trata inadecuadamente con anticoagulación prolongada o trombólisis. El pronóstico es malo, con una media de supervivencia de 12 meses desde el inicio de los síntomas. Presentamos el caso de una paciente a quien se diagnosticó preoperatoriamente un sarcoma intimal de la arteria pulmonar que se sometió a resección quirúgica, sin que se evidenciase recurrencia en el seguimiento a largo plazo. También se realiza una revisión de la bibliografía

Intimal sarcoma of the pulmonary artery is a rare tumor that is usually diagnosed during surgery or autopsy. Such tumors are characterized by local growth, with only slight ability to metastasize. Diagnosis is difficult and often delayed owing to the nonspecific nature of the symptoms. Since intimal sarcoma of the pulmonary artery is so rare and insidious it is often confused with pulmonary thromboembolism and is therefore treated inappropriately with prolonged anticoagulation or thrombolysis. With a mean survival of 12 months from the onset of symptoms, the prognosis is poor. We present the case of a woman who was preoperatively diagnosed with intimal sarcoma of the pulmonary artery and who underwent surgical resection with no apparent recurrence at long term follow-up. A review of the literature is also included

Otalgia como presentación de tuberculosis primaria de nasofaringe / Otalgia as presentation of primary nasopharinx tuberculosis

Presentamos una paciente de 63 años que padecía otalgia izquierda de más de seis meses de evolución. A la exploración, la otoscopia era normal, mientras que la fibroscopia nasal demostró una asimetría en la nasofaringe. La TC confirmó la presencia de una masa nasofaríngea izquierda. Se realizó una exéresis endoscópica de la lesión nasofaríngea. La anatomía patológica demostró una granulomatosis necrotizante, aunque no fue posible hallar bacilos ácido-alcohol resistentes. Se consideró el diagnóstico de tuberculosis nasofaríngea. Tras 36 meses de seguimiento, la endoscopia nasal y la TC no demuestran signos de recidiva. La discusión se centra en la inclusión de la patología nasofaríngea en el diagnóstico diferencial de las otalgias, el diagnóstico histopatológico de los granulomas y la indicación de tratamiento antituberculoso en casos limitados de tuberculosis extrapulmonar

We report a case of a 63 year-old woman who presented with left otalgia during more than six months. On examination, otoscopy was normal, whereas flexible nasopharyngoscopy revealed an asymmetry in the nasopharynx. CT scans confirmed the presence of a left nasopharyngeal mass. A transnasal endoscopic removal of the nasopharyngeal lesion was performed. Necrotizing granulomatosis was found. Tuberculosis of the nasopharynx was considered the final diagnosis, but oral treatment was not started. After 36 months of follow-up, nasal endoscopy and CT images show no sign of recurrence. Discussion is focused on the inclusion of nasopharyngeal diseases in otalgia differential diagnosis, histopathological diagnosis of granulomas and the need of any further treatment for these limited cases of extrapulmonary tuberculosis

Pseudohipertrofia de bandas ventriculares por deformación del cartílago tiroides / Pseudohypertrophy of the ventricular bands due to deformation of the thyroid cartilage

La disfonía por hipertrofia de las bandas ventriculares (disfonia plicae ventricularis) es una causa frecuente de disfonía funcional, relacionada con una tensión muscular excesiva en la región laríngea. Sin embargo, en algunos pacientes puede objetivarse una causa mecánica para dicha disfonía funcional por hipertrofia de bandas, que suele tratarse de una deformidad del cartílago tiroides. Presentamos un caso de hipertrofia de bandas ventriculares que fue tratado mediante foniatría, seguida de laringoscopia directa y microcirugía endolaríngea, con exéresis parcial de las mismas, sin mejoría. Dicho fracaso estaba en relación con una pseudohipertrofia de bandas por deformidad del cartílago tiroides, que fue confirmada en tomografia computarizada

Hoarseness due to phonation by the false cords (dysphonia plicae ventricularis) is a common cause of functional dysphonia, in relation to excessive muscular tension in the larynx area. Nevertheless, a mechanic cause can be observed in some cases with dysphonia plicae ventricularis, which is usually due to deformation of the thyroid cartilage. We report a case with hypertrophy ofthe ventricular bands which was treated by vocal rehabilitation followed by suspension laryngoscopy with parti al removal of the ventricular bands, without further improvement. This failure was related to a pseudohypertrophy ofthe ventricular bands, due to deformation of the thyroid cartilage, which was confirmed by computed tomography

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