Selective leaching of rare earths, base metals and precious metals from used smartphones.

Discarded smartphones represent a valuable source of rare earths (REE), base metals and precious metals. This study focussed on the optimisation of three-stage selective leaching conditions for REE, copper and precious metals (Au and Ag), respectively, contained in printed circuit boards (PCBs) found in end-of-life smartphones. The effects of several leaching conditions, such as sulphuric acid and thiourea concentrations, were investigated using a statistical approach based on a design of experiments using Box-Behnken methodology.

Analytical strategies for sensitive and precise determination of Sr/Sr in olive oil through ion extraction, chromatographic separation, and multicollector inductively-coupled plasma mass-spectrometry.

Several food regulatory bodies regard olive oil as highly susceptible to food fraud, largely due to its substantial economic worth. Precise analytical tools are being developed to uncover these types of fraud. This study examines an innovative approach to extract strontium (Sr) from the olive oil matrix (via EDTA complexation and ion-exchange chromatography) and to determine its isotope composition by MC-ICP-MS.

Levels of naturally occurring radioisotopes in local and imported bottled drinking water available in Québec City, Canada.

Consumption of local and imported bottled water in Canada has greatly increased during the past three decades. While the presence of natural radioactivity is often overlooked when dealing with the water quality of these bottled products, it could contribute substantially to the uptake of radionuclides especially when sourced from regions with higher radioactivity levels compared to where it is consumed. In this study, the activity of several naturally occurring radionuclides (i.

Comparison of radium-226 separation methods based on chromatographic and extraction resins for its determination by ICP-MS in drinking waters.

Over the past century, human activities have contributed to the release of Ra (t  = 1,600 y) in the environment, increasing the potential risks for human exposure and thus prompting scientists to monitor it. Inductively coupled plasma mass spectrometry (ICP-MS) is an alternative to alpha-spectrometry for the quantification of Ra. However, the performances of radioanalytical procedures are rarely compared in a rigorous framework, which means that researchers may choose one on subjective factors or guesses.

Metal-Enhanced Hg-Responsive Fluorescent Nanoprobes: From Morphological Design to Application to Natural Waters.

Metal-enhanced fluorescence (MEF) is a powerful tool in the design of sensitive chemical sensors by improving brightness and photostability of target-responsive fluorophores. Compounding these advantages with the modest hardware requirements of fluorescence sensing compared to that of centralized elemental analysis instruments, thus expanding the use of MEF to the detection of low-level inorganic pollutants, is a compelling aspiration. Among the latter, monitoring mercury in the environment, where some of its species disseminate through the food chain and, in time, to humans, has elicited a broad research effort toward the development of Hg-responsive fluorescent sensors.

Olive Oil Traceability Studies Using Inorganic and Isotopic Signatures: A Review.

The olive oil industry is subject to significant fraudulent practices that can lead to serious economic implications and even affect consumer health. Therefore, many analytical strategies have been developed for olive oil's geographic authentication, including multi-elemental and isotopic analyses. In the first part of this review, the range of multi-elemental concentrations recorded in olive oil from the main olive oil-producing countries is discussed.

Rapid determination of Pb and Po by sequential cloud point extraction for environmental monitoring.

A new sequential cloud point extraction (CPE) procedure was developed and validated for the determination of Pb and Po by ICP-MS/MS and alpha spectrometry, respectively. Two distinct CPE systems using 4',4''(5'')-di--butyldicyclohexano-18-crown-6 and ,,','-tetraoctyldiglycolamide as chelating agents were performed sequentially on the same sample. Method detection limits of 13 and 3.

Determination of polonium-210 in environmental samples using diglycolamide-based cloud point extraction coupled to alpha spectrometry analysis.

This study presents a novel cloud point extraction (CPE) methodology for the separation and enrichment of polonium-210 prior to alpha-spectrometric quantification in water, urine and digested samples. The extractive behaviour of diglycolamide-based ligands towards Po by CPE was determined and optimised in various acidic conditions. The extraction efficiency and selectivity of the CPE systems depend greatly on the choice of the extracting agent and acidic conditions.

Understanding Selectivity of Mesoporous Silica-Grafted Diglycolamide-Type Ligands in the Solid-Phase Extraction of Rare Earths.

Rare earth elements (REEs) and their compounds are essential for rapidly developing modern technologies. These materials are especially critical in the area of green/sustainable energy; however, only very high-purity fractions are appropriate for these applications. Yet, achieving efficient REE separation and purification in an economically and environmentally effective way remains a challenge.

Quantification of titanium dioxide nanoparticles in human urine by single-particle ICP-MS.

The increasing use of titanium dioxide nanoparticles in daily use consumer products such as cosmetics, personal care products, food additives, and even medicine has led to growing concerns regarding human safety. It would be ideal to track exposure to this emerging nanopollutant, for example through bioassays, however, so far nanoparticle assessment in biological matrices such as urine remains challenging. The lack of data is mainly due to the limitations of the current metrology, but also to the low expected concentration in human samples.

Assessment of strategies for the formation of stable suspensions of titanium dioxide nanoparticles in aqueous media suitable for the analysis of biological fluids.

Due to their omnipresence in consumer products, there is a growing concern about the potential effects of nanoparticles on human health. Toxicological assessment and NP end-product studies require proper quantification of these materials in biological fluids. However, their quantifications in these media require stable predispersed NP solutions in aqueous media to enable the fortification in the matrices of interest or the preparation of calibration standards.

Revealing the Hydrolysis Mechanism of a Hg-Reactive Fluorescein Probe: Novel Insights on Thionocarbonated Dyes.

As one of the most toxic metal pollutants, mercury is the subject of extensive research to improve current detection strategies, notably to develop sensitive, selective, fast, and affordable Hg-responsive fluorescent probes. Comprehending the sensing mechanism of these molecules is a crucial step in their design and optimization of their performance. Herein, a new fluorescein-based thionocarbonate-appended Hg-sensitive probe was synthesized to study the hydrolysis reactions involved in the sensing process.

A rapid sequential chromatographic separation of U- and Th-decay series radionuclides in water samples.

A new sequential protocol for the separation and preconcentration of U, Th, Ra, Po and Pb for the same sample aliquot has been designed. The optimized stacking of chromatographic resins [TRU, Sr and a new hybrid Ra resin (composed of Analig Ra-01 and cation exchange AG50Wx8)] enables a rapid loading of the sample (less than 75 min for 300 mL of samples) while ensuring a high retention of the analytes of interest. The use of a hybrid Ra resin allows the complete and selective extraction of Ra on a solid support, a feature lacking in other sequential separation procedures.

Size-Selective Separation of Rare Earth Elements Using Functionalized Mesoporous Silica Materials.

The separation and preconcentration of rare earth elements (REEs) from mineral concentrates in an economically and environmentally sustainable manner are difficult tasks due to their similar physicochemical properties. Herein, a series of tetradentate phenylenedioxy diamide (PDDA) ligands were synthesized and grafted on large-pore three-dimensional KIT-6 mesoporous silica. In solid-phase extraction, the hybrid sorbents enable a size-selective separation of REEs on the basis of the bite angles of the ligands.

Toxicity of tailing leachates from a niobium mine toward three aquatic organisms.

The aim of this research was to assess the ecotoxicity of leachates originating from a niobium mine located in Canada. These tailings contain considerable amounts of carbonates and phosphates and could potentially be used as fertilizer for agriculture. However, the presence of different contaminants linked with the ores mined, including rare earth elements and daughter elements of the uranium disintegration chain is of concern.

Dosimetric properties of colloidal quantum dot-based systems for scintillation dosimetry.

Colloidal quantum dots (cQDs) are starting to be used in radiation detection, either combined with an organic fluorophore or used as a sole luminescent material. In the latter case, only few studies report on cQD-based detectors for medical applications, especially for scintillation dosimetry in radiation therapy. Moreover, most of these studies focus on the effects of radiation on cQD photoluminescence but do not look into the properties of the scintillation signal itself.

Characterization of a binary system composed of luminescent quantum dots for liquid scintillation.

Scintillation dosimetry has evolved towards utilizing 3D liquid dosimeters to perform quality assurance verification of complex treatment configuration for photon, electron and proton beams. However, most of the fluorophores utilized in these dosimeters are alike and present limitations. This study aims to establish the profile of CdSe colloidal quantum dots (cQDs) that were given the role of the fluorophore in a binary liquid scintillation system.

Recent Advances in the Separation of Rare Earth Elements Using Mesoporous Hybrid Materials.

Over the past decades, the need for rare earth elements (REEs) has increased substantially, mostly because these elements are used as valuable additives in advanced technologies. However, the difference in ionic radius between neighboring REEs is small, which renders an efficient sized-based separation extremely challenging. Among different types of extraction methods, solid-phase extraction (SPE) is a promising candidate, featuring high enrichment factor, rapid adsorption kinetics, reduced solvent consumption and minimized waste generation.

Determination of Pb in environmental samples after cloud point extraction using crown ether.

In the present study, a new cloud point extraction methodology based on the selective preconcentration and the extraction of stable lead in acidic conditions with 4',4''(5'')-di-tert-butyldicyclohexano-18-crown-6 as a chelating agent was developed, optimized and validated. A mixture of Triton X-114 as non-ionic surfactant and CTAB as cationic surfactant was used to produce micellar structures that incorporate the chelating agent. Phase separation, induced by coacervation, was achieved by increasing the temperature of the system above the cloud point temperature.

Selective Separation and Preconcentration of Scandium with Mesoporous Silica.

Separation and preconcentration of scandium (Sc) were successfully achieved using a mesoporous silica support that showed good selectivity for this element. Unmodified mesoporous silica materials were used as an extracting medium in a solid-liquid extraction (SLE) process. Selectivity, extraction capacity, kinetics of extraction, and reusability under acidic conditions were investigated.

Highly Efficient and Selective Recovery of Rare Earth Elements Using Mesoporous Silica Functionalized by Preorganized Chelating Ligands.

Separating the rare earth elements (REEs) in an economically and environmentally sustainable manner is one of the most pressing technological issues of our time. Herein, a series of preorganized bidentate phthaloyl diamide (PA) ligands was synthesized and grafted on large-pore 3-dimensional (3-D) KIT-6 mesoporous silica. The synthesized sorbents were fully characterized by N physisorption, FT-IR, C cross-polarization (CP) and Si magic-angle spinning (MAS) NMR, thermogravimetric analysis-differential thermal analysis (TGA-DTA), and elemental analysis.

Functionalization of Mesoporous Carbon Materials for Selective Separation of Lanthanides under Acidic Conditions.

New functional mesoporous carbon sorbents were successfully synthesized to overcome some issues of solid-liquid extraction (e.g., selectivity, extraction capacity, and reusability under acidic conditions) in production of pure lanthanides (Ln).

A comparative study of sample dissolution techniques and plasma-based instruments for the precise and accurate quantification of REEs in mineral matrices.

The recent commercialisation of inductively coupled plasma tandem mass spectrometric (ICP-MS/MS) instruments has provided analytical chemists with a new tool to properly quantify atomic composition in a variety of matrices with minimal sample preparation. In this article, we report on our assessment of the compatibility of 3 sample preparation techniques (open-vessel acid digestion, microwave digestion and alkaline fusion) for the quantification of rare earth elements (REEs) in mineral matrices. The combination of the high digestion temperatures (1050 °C) and using LiBO as a flux was the most effective strategy for the digestion of all rare earth elements in mineral matrices and was compatible with ICP-MS/MS measurements.

Functionalization of mesoporous materials for lanthanide and actinide extraction.

Among the energy sources currently available that could address our insatiable appetite for energy and minimize our CO2 emission, solar, wind, and nuclear energy currently occupy an increasing portion of our energy portfolio. The energy associated with these sources can however only be harnessed after mineral resources containing valuable constituents such as actinides (Ac) and rare earth elements (REEs) are extracted, purified and transformed into components necessary for the conversion of energy into electricity. Unfortunately, the environmental impacts resulting from their manufacture including the generation of undesirable and, sometimes, radioactive wastes and the non-renewable nature of the mineral resources, to name a few, have emerged as challenges that should be addressed by the scientific community.

Isotopic signature of selected lanthanides for nuclear activities profiling using cloud point extraction and ICP-MS/MS.

The presence of fission products, which include numerous isotopes of lanthanides, can impact the isotopic ratios of these elements in the environment. A cloud point extraction (CPE) method was used as a preconcentration/separation strategy prior to measurement of isotopic ratios of three lanthanides (Nd, Sm, and Eu) by inductively coupled plasma tandem mass spectrometry (ICP-MS/MS). To minimise polyatomic interference, the combination of interferents removal by CPE, reaction/collision cell conditions in He and NH3 mode and tandem quadrupole configuration was investigated and provided optimal results for the determination of isotopic ratio in environmental samples.