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1.
Australas J Ageing ; 2024 Apr 04.
Article in English | MEDLINE | ID: mdl-38576179

ABSTRACT

OBJECTIVES: (1) To investigate the prevalence of frailty defined by the Hospital Frailty Risk Score (HFRS), a new scale for assessing frailty, in older patients with acute coronary syndrome (ACS); (2) To identify associations between frailty and the prescriptions of cardiovascular medications, percutaneous coronary intervention (PCI) and in-hospital adverse outcomes. METHODS: An observational study was conducted in patients aged older than 60 years with ACS at Thong Nhat Hospital from August to December 2022. The Hospital Frailty Risk Score is retrospectively calculated for all participants based on ICD-10 codes, and those with HFRS scores ≥5 were defined as frail. Logistic regression models were applied to examine the relationship between frailty and the study outcomes. RESULTS: There were 511 participants in the study. The median age was 72.7, 60% were male and 29% were frail. Frailty was associated with lower odds of beta-blocker use at admission (OR .49 95% CI .25-.94), treatment with PCI during hospitalisation (OR .48, 95% CI .30-.75), but did not show an association with prescriptions of cardiovascular drugs at discharge. Frailty was significantly associated with increased odds of adverse outcomes, including major bleeding (OR 4.07, 95% CI1.73-9.54), hospital-acquired pneumonia (OR 2.55, 95% CI 1.20-5.42), all-cause in-hospital mortality (OR 3.14, 95% CI 1.37-7.20) and non-cardiovascular in-hospital mortality (OR 10.73, 95% CI 1.93-59.55). CONCLUSIONS: The HFRS was an effective tool for stratifying frailty and predicting adverse health outcomes in older patients with ACS. Further research is needed to compare the HFRS with other frailty assessment tools in this population.

2.
Materials (Basel) ; 16(21)2023 Oct 27.
Article in English | MEDLINE | ID: mdl-37959513

ABSTRACT

The traditional roasting technique using sodium salts in vanadium production has been disadvantageous due to the large consumption of energy and the emission of harmful gases. A modified process using molten salt roasting and water leaching to extract vanadium and titanium from domestic titanomagnetite concentrate was investigated. The roasting process was performed under optimal conditions: the weight ratio between the sample and NaOH of 1:1, the temperature of 400 °C, and the experiment time 90 min, and the conversion of vanadium could be maximized to 90%. The optimization of water leaching (at 60 °C for 90 min with a pulp density of 0.05 g/mL) could extract 98% of the vanadium from the roasted products into the solution, leaving titanium and iron remaining in the residue. Further purification of vanadium and titanium using the precipitation/hydrolysis process followed by calcination obtained the final products V2O5 and TiO2 with high purities of 90% and 96%, respectively. A potential approach with modification of the roasting stage using NaOH was proposed, which was not only efficient to selectively extract the value metals from the titanomagnetite but also eco-friendly based on the reduction in energy consumption and emission of harmful gases.

3.
Waste Manag ; 114: 148-165, 2020 Aug 01.
Article in English | MEDLINE | ID: mdl-32673979

ABSTRACT

Spent auto-catalysts are considered as promising platinum group metals (PGMs) resources based on their rapidly increasing demand along with the underlying uncertainty of the sustainability and long-term availability of PGMs. Recycling spent auto-catalysts presents attractive advantages, particularly for the conservation of primary resources reserves, and for the reduction of negative environmental impact due to exploitation. PGM reclamation is the major aim of recycling operations despite their minor concentration in spent auto-catalysts, which implies that the remaining materials are disposed of as unwanted solid waste after the extraction process. This poses a genuine challenge, as well as a motivation to develop recycling processes for spent auto-catalysts capable of recovering all components/valuable metals, while moderating environmental pollution and global warming. The focus herein involves the description of the available technologies, including pyro- and hydro-metallurgical processes, to recover PGMs from spent auto-catalysts, and specifically an analysis of the developmental trends in recycling methods to ensure "sustainable metallurgy".


Subject(s)
Metallurgy , Recycling , Catalysis , Metals , Solid Waste
4.
J Hazard Mater ; 379: 120772, 2019 11 05.
Article in English | MEDLINE | ID: mdl-31254787

ABSTRACT

Total recycling of all valuable metals such as PGMs, Ce, Al and Mg from the spent automobile catalysts has been explored. The alkali roasting was performed under NaOH, 0.5-3.0 g; temperature, 300-800 °C; and time, 10-60 min. The phase transformation from cordierite to the soluble products (NaAlO2, Na2MgSiO4) was influenced by the temperature, following the diffusion-controlled model (Ea(roasting), 6.4 kJ/mol). XRD analysis of the roasted mass revealed that the refractory phases of cordierite and γ-alumina could be eliminated at ≥600 °C at sample-to-NaOH mass ratio, 1:1. The leaching of the roasted mass followed an intermediate-controlled mechanism for aluminum leaching with (Ea(Al-leaching) value of 20.3 kJ/mol), while it was diffusion-controlled for magnesium leaching (Ea(Mg-leaching), 8.9 kJ/mol). At the optimum leaching condition (1.0 M H2SO4, 90 °C, 60 min, yielding >95% aluminum and magnesium), a significant amount of PGMs was also leached. Thereafter, the cementation process was investigated with Al0-powder that could precipitate >99% PGMs within 15 min at 90 °C. The yielded concentrate of PGMs and CeO2 was subsequently leached in 6.0 M HCl with 2.0 M NaClO3 that dissolved >97% PGMs, leaving the residue as the CeO2 concentrate. Individual metals can be recovered by following established separation and purification techniques.

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