RESUMEN
Microwave pyrolysis bio-oil from waste paper and K60 silica gel has successfully been utilised to synthesise mesoporous carbon-silica composites with uniquely tuneable surface properties, where functionality and structural characteristics can be altered and even enhanced by curing at different temperatures. This temperature-dependence resulted in composites ranging from highly oxygenated polymerised bio-oil composites at 300 °C to aromatic carbonaceous materials covering the silica surface at 800 °C, making them attractive materials for gold recovery from mining wastewater. The composite materials exhibit exceptional ability and selectivity to recover gold from dilute solutions. Metal adsorption on the surface of these composites proceeded via both chemisorption and physisorption leading to the reduction of Au(iii) to Au(0), resulting in high recovery capacities for gold. Composite material prepared at 500 °C demonstrated the optimum combination of surface functionality and porosity, allowing for an adsorption capacity of 320 mg g-1 of gold and with 99.5% removal being achieved at concentrations mimicking those of real-life mine tailing wastes. All materials pioneered in this research display great potential as selective adsorbents for the recovery of gold from acidic media.
RESUMEN
The incidence of aortoesophageal fistula after thoracic endovascular aortic repair has increased following an increase in thoracic endovascular aortic procedures. A 68-year-old man was diagnosed with aortoesophageal fistula 6 years after thoracic endovascular aortic repair of a descending aortic aneurysm. Due to massive hematemesis and instability, he underwent a left thoracotomy, graft repair of the aorta with stent removal, gastrostomy, and proximal esophagostomy. Unfortunately, he died 1 week later due to sepsis. Aortoesophageal fistula may present long after thoracic endovascular aortic repair, and clinicians treating such cases should always be aware of this complication.