Chemical Separation Method Research Articles

A Mini Review on the Opportunities for Membrane Pervaporation Technology for Energy-efficient Removal of Dispersed Oil and Dissolved Hydrocarbons from Produced Water

Produced water is reported to have the largest volume of waste stream associated with hydrocarbon recovery. It was estimated to increase from 250 million B/D in 2007 to more than 300 million B/D between 2010 and 2012. Market research conducted by Adroit put the globally produced water treatment market at a value of USD 5.10 billion in 2022. This value is anticipated to be USD 9.80 billion in 2032 at a compound annual growth rate (CAGR) of 5.80% over the prediction period. Oil and gas companies have been mandated to comply with the newly enacted environmental regulations that require extensive treatment of this water before discharge or reuse. The limited quantity of freshwater resources coupled with the increasing oil and gas production activities has made it necessary for all stakeholders to look for sustainable management of this water. Presently, a certain percentage of produced water is reused while the rest is discharged into the ocean. In both cases, the water needs to be thoroughly treated. The choice of technologies for produced water treatment depends on numerous factors, such as the chemical composition of the water and the level of purity that must be attained before disposal, recycling, or re-use. Some of the technologies used for produced water treatment include physical separation methods such as gravity, adsorption, filtration, coalescence, cyclones, flotation, centrifuges, membranes, and oxidation. There are also chemical and biological separation methods. Contaminants such as small droplets of dispersed oil and dissolved hydrocarbons (DODHs) are very challenging to remove using the above-listed water treatment technologies. Moreover, the use of membrane technology has been limited only to the use of reverse osmosis and membrane filtration for removing salinity, metals, and other inorganics. This article highlights the opportunities for the use of membrane vapor permeation and pervaporation for the removal of the small droplets of DODHs, which have been reported to be very challenging contaminants to remove. The use of 3D printing technology for the fabrication of membrane materials was reviewed. The 3D membrane development method can be used to fabricate almost any shape of the material in a highly customized manner using computer-aided design. The information presented in this article will serve as a useful reference for the technologies used for a sustainable water treatment strategy in the oil and gas industry.

Research progress on lithium isotopes separation by chemical exchange with crown ethers decorated materials

The separation of lithium isotopes (6Li and 7Li) is of great importance for the nuclear industry. The lithium amalgam method is the only lithium isotopes separation process in industry, and the extensive use of mercury has raised concerns about its potential environmental hazards, which have prompted the search for more efficient and environmentally friendly alternatives. Crown ethers can bind lithium ions highly selectively and separate lithium isotopes effectively. A chemical exchange-based lithium isotopes separation method using crown ether decorated materials could be a viable and cost-effective alternative to the lithium amalgam method. In this review, we provide a systematic summary of the recent advances in lithium isotopes separation using crown ether decorated materials.

Efficient EVs separation and detection by an alumina-nanochannel-array-membrane integrated microfluidic chip and an antibody barcode biochip

BackgroundSmall endosome-derived lipid nanovesicles (30–200 nm) are actively secreted by living cells and serve as pivotal biomarkers for early cancer diagnosis. However, the study of extracellular vesicles (EVs) requires isolation and purification from various body fluids. Although traditional EVs isolation and detection technologies are mature, they usually require large amount of sample, consumes long-time, and have relatively low-throughput. How to efficiently isolate, purify and detect these structurally specific EVs from body fluids with high-throughput remains a great challenge in in vitro diagnostics and clinical research. ResultsHerein, we suggest a nanosized microfluidic device for efficient and economical EVs filtration based on an alumina nanochannel array membrane. We evaluated the filtration device performance of alumina membranes with different diameters and found that an optimized chamber array with a hydrophilic-treated channel diameter of 90 nm could realize a filtration efficiency of up to 82% without any assistance from chemical or physical separation methods. Importantly, by integrating meticulously designed multichannel microfluidic biochips, EVs can be captured in-situ and monitored by antibody barcode biochip. The proposed filtration chip together with the high-throughput detection chip were capable of filtration of a few tens of μL samples and recognition of different phonotypes. The practical filtration and detection of EVs from clinical samples demonstrated the high performance of the device. SignificantOverall, this work provides a cost-effective, highly efficient and automated EVs filtration chip and detection dual-function integrated chip platform, which can directly separate EVs from serum or cerebrospinal fluid with an efficiency of 82% and conduct in-situ detection. This small fluidic device can provide a powerful tool for highly efficient identifying and analyzing EVs, presenting great application potential in clinical detection.

A Review on Nano Fluid Production, Mathematical Modelling and Applications

Recently, nano fluids have taken on a significant role in many human endeavours. A fluid called a nanofluid includes nanoparticles, also called nanoparticles. Colloidal suspensions of nanoparticles in a base fluid are what these fluids are made of. The numerous production procedures and mathematical interpretation models for nanofluids are examined in this review study. Marangoni convection’s advantages, which enhance heat transfer and balance temperature distribution, are underlined. The effects of thermophoresis on surface tension as well as surface tension in laminar natural convection are also discussed in this work. The characteristics of carbon nanotubes and their prospective medical uses are covered in the article. The study covers electrochemical double layer capacitors, which offer greater safety, longer cycle stability, and better power densities. The study explores the impact of magnetic fields on entropy formation and natural convection in a hybrid nanofluid enclosure, revealing four distinct models based on thermal conductivity and viscosity correlations. The information review work is relevant. The review information work is relevant to flow tracers, prosthetic heart valves, oil pipelines, chemical industry separation methods, and oil recovery.

Case studies of three geological archives for rare radionuclide measurements using accelerator mass spectrometry

Long-lived radionuclides in our environment provide important information on natural and anthropogenic processes. Their presence and concentration reflect the balance of production and decay. Geological archives store such information and the nuclides can be chemically extracted from the bulk sample. Accelerator mass spectrometry (AMS) represents a sensitive method to quantify those nuclides at natural levels. Three different terrestrial archives are discussed here as examples for radionuclide extraction using various chemical separation methods for subsequent AMS measurements. We focus on sample preparation for the cosmogenic radionuclides 10Be and 26Al, various anthropogenic actinide isotopes such as U, Pu, and Am as well as the astrophysically interesting nuclides 41Ca, 53Mn, and 60Fe. The processed materials cover samples with masses between a few mg and up to a few hundred kg and protocols are presented for the quantitative extraction of some 10,000 atoms of cosmogenic or interstellar origin per sample and even as low as a few hundred actinide atoms.

Challenges of polyester-cotton textiles co-fractionation

Waste problem on plastic relates to micro plastic issue and synthetic textile fibers pronounce part of the problem. Inherently the problems in recycling are rising form the structure of the textiles, comprising of textile fiber blends, yarn and garment structures and well the components typical for clothing. In chemical separation methods, the sensitivity of both of the polymers defines strict limits to which conditions are possible without depolymerizing or damaging markedly either of the main components. In this paper we discuss the challange of available processes.

Accelerator-Based Production of Scandium Radioisotopes for Applications in Prostate Cancer: Toward Building a Pipeline for Rapid Development of Novel Theranostics.

In the field of nuclear medicine, the β+ -emitting 43Sc and β- -emitting 47Sc are promising candidates in cancer diagnosis and targeted radionuclide therapy (TRT) due to their favorable decay schema and shared pharmacokinetics as a true theranostic pair. Additionally, scandium is a group-3 transition metal (like 177Lu) and exhibits affinity for DOTA-based chelators, which have been studied in depth, making the barrier to implementation lower for 43/47Sc than for other proposed true theranostics. Before 43/47Sc can see widespread pre-clinical evaluation, however, an accessible production methodology must be established and each isotope's radiolabeling and animal imaging capabilities studied with a widely utilized tracer. As such, a simple means of converting an 18 MeV biomedical cyclotron to support solid targets and produce 43Sc via the 42Ca(d,n)43Sc reaction has been devised, exhibiting reasonable yields. The NatTi(γ,p)47Sc reaction is also investigated along with the successful implementation of chemical separation and purification methods for 43/47Sc. The conjugation of 43/47Sc with PSMA-617 at specific activities of up to 8.94 MBq/nmol and the subsequent imaging of LNCaP-ENZaR tumor xenografts in mouse models with both 43/47Sc-PSMA-617 are also presented.

Способи сепарації на підготовчій стадії проведення криміналістичної експертизи речових доказів

In expert practice, questions often arise related to the separation (separation) of research objects from a mixture of dissimilar particles of solid materials, liquids of different densities, emulsions, two-phase media. During the study, physical and chemical separation methods are used. The choice of the separation method depends on the percentage composition and properties of the mixture and its constituent components. Expert research is carried out using various methods of separation: by mass (inertial), by size, electrical, magnetic, radiometric, photometric, etc. Chemical separation is its separate type. Analysis of expert practice indicates that separation is mainly applied during the forensic investigation of metals and alloys (solids), drugs (solids, liquid substances) and petroleum products (liquid substances). The article analyzes the methods of separation at the preparatory stage of the expert study of microparticles of precious metals and handicraft drugs. Forensic investigation of metal and alloy products is one of the most difficult, since the detection and separation of microparticles of the metal under study from other metal particles and their subsequent identification require the use of both chemical and instrumental research methods. The separation of the metal under study from the mixture of other metal particles was carried out by the method of mechanical and magnetic separation and chemical (selective dissolution) separation. During the expert study of acetylated opium using chromatographic methods, difficulties often arise associated with the separation of components due to the presence of a large amount of ballast substances (in particular, chlorophyll) extracted from poppy straw in acetylated opium. The use of an inertial separation method makes it possible to speed up the separation of an aqueous solution of a narcotic drug emulsion and an extracting organic solvent.

Direct biomolecule discrimination in mixed samples using nanogap-based single-molecule electrical measurement

In single-molecule measurements, metal nanogap electrodes directly measure the current of a single molecule. This technique has been actively investigated as a new detection method for a variety of samples. Machine learning has been applied to analyze signals derived from single molecules to improve the identification accuracy. However, conventional identification methods have drawbacks, such as the requirement of data to be measured for each target molecule and the electronic structure variation of the nanogap electrode. In this study, we report a technique for identifying molecules based on single-molecule measurement data measured only in mixed sample solutions. Compared with conventional methods that require training classifiers on measurement data from individual samples, our proposed method successfully predicts the mixing ratio from the measurement data in mixed solutions. This demonstrates the possibility of identifying single molecules using only data from mixed solutions, without prior training. This method is anticipated to be particularly useful for the analysis of biological samples in which chemical separation methods are not applicable, thereby increasing the potential for single-molecule measurements to be widely adopted as an analytical technique.

New Trends in Separation Techniques of Lithium Isotopes: A Review of Chemical Separation Methods.

In terms of isotopic technologies, it is essential to be able to produce materials with an enriched isotopic abundance (i.e., a compound isotopic labelled with 2H, 13C, 6Li, 18O or 37Cl), which is one that differs from natural abundance. The isotopic-labelled compounds can be used to study different natural processes (like compounds labelled with 2H, 13C, or 18O), or they can be used to produce other isotopes as in the case of 6Li, which can be used to produce 3H, or to produce LiH that acts like a protection shield against fast neutrons. At the same time, 7Li isotope can be used as a pH controller in nuclear reactors. The COLEX process, which is currently the only technology available to produce 6Li at industrial scale, has environmental drawbacks due to generation of Hg waste and vapours. Therefore, there is a need for new eco-friendly technologies for separation of 6Li. The separation factor of 6Li/7Li with chemical extraction methods in two liquid phases using crown ethers is comparable to that of COLEX method, but has the disadvantages of low distribution coefficient of Li and the loss of crown ethers during the extraction. Electrochemical separation of lithium isotopes through the difference in migration rates between 6Li and 7Li is one of the green and promising alternatives for the separation of lithium isotopes, but this methodology requires complicated experimental setup and optimisation. Displacement chromatography methods like ion exchange in different experimental configurations have been also applied to enrich 6Li with promising results. Besides separation methods, there is also a need for development of new analysis methods (ICP-MS, MC-ICP-MS, TIMS) for reliable determination of Li isotope ratios upon enrichment. Considering all the above-mentioned facts, this paper will try to emphasize the current trends in separation techniques of lithium isotopes by exposing all the chemical separation and spectrometric analysis methods, and highlighting their advantages and disadvantages.

On developing a practical safety culture for the advanced reactor workforce: Experiences of working with sodium

The Versatile Test Reactor is meant to fill a need in the advanced nuclear reactor development community. Accelerated nuclear testing of fuels and materials is needed to allow designs to proceed. To accomplish this, a fast neutron spectrum is needed. To have a fast neutron spectrum, the reactor coolant needs to not only have excellent heat transfer properties to sufficiently cool the reactor core, but also not significantly slow neutrons down following their birth in the fission process. Sodium is an excellent coolant choice that can fulfill these needs and many others. Sodium is the sixth most abundant element in the Earth’s crust and can be acquired easily through simple chemical separation methods. Sodium, however, reacts when in contact with water and air, but with proper precautions, these scenarios can be avoided. Nuclear reactors that utilize molten sodium as a primary heat transfer medium [a.k.a. sodium-cooled fast-neutron reactors, or SFRs, Figure 1 (1)] provide unique challenges in their daily operation, and therefore require focused training for researchers, scientists, staff, and employees alike to understand these unique challenges. Therefore, a comprehensive understanding of sodium properties is needed by all personnel involved in the design, construction, operation, experiment planning and execution of SFRs. Additionally, several commercial advanced reactor designs are under development which will use sodium for the reactor coolant. These advanced reactor designs include the Natrium reactor from TerraPower and GE-Hitachi (2), the ARC-100 reactor from Advanced Reactor Concepts (3), and the Aurora reactor from Oklo (4).

Simultaneous peeling of precious metals in cathode and anode of spent ternary batteries using electrolysis

Recycling spent lithium-ion batteries (LIBs) is of great significance for both environmental protection and resource recycling. However, there are only a few studies on the simultaneous peeling and recycling of battery anode and cathode. Thus, this work proposed a new process for peeling cathode and anode in spent LIBs to solve this problem. The cathode and anode of the spent LIBs were used to form an electrolytic cell to simultaneously realize the peeling of the electrode materials and current collectors and a large amount of Li+ leaching. The leaching rate of Li+ reached 96.19 % under optimal conditions. In addition, the Li+ in the electrolyte can be directly heated and concentrated to be recovered in the form of Li2CO3. Furthermore, the peeling of cathode materials was caused by the gas shock and defluorination of polyvinylidene fluoride (PVDF). For the Li-free materials, the chemical separation and precipitation method was used to separate and recover Ni, Co, and Mn. In conclusion, this experiment carried out an environmentally friendly electrolysis recycling technique to realize the selective pre-recovery of Li+, the separation of electrode materials with current collectors, and the high purity recovery of current collectors. A new peeling mechanism for the electrolysis recycling technique was also explored. Therefore, this study was expected to provide a useful reference for the electrolysis recycling technique.

Research progress of CO2 separation technology by solvent absorption

The combustion of fossil fuels emits a large amount of CO2, which causes the greenhouse effect and leads to global warming and poses a serious threat to life on earth. CO2 capture technology can effectively reduce the concentration of CO2 in the atmosphere, alleviate the greenhouse effect, and improve the environment. CO2 capture technologies include absorption, membrane separation and adsorption separation, among which chemical absorption and separation have the advantages of high efficiency, low cost and easy availability of materials. In this paper, the advantages and disadvantages of three main chemical absorption and separation methods (inorganic reagents, organic amines and ionic liquids) adsorb CO2 are summarized. Among inorganic adsorbents, NH3·H2O can achieve rapid and efficient absorption of CO2, and it is relatively stable and not easy to degrade. Common types of organic amine adsorbents are monoethanolamine, methanolamine, and sterically hindered amine. However, it is difficult for a single organic amine adsorbent to meet the requirements of high absorption rate, high absorption capacity and low reaction heat at the same time. Therefore, mixing organic amine absorbents with different characteristics can improve their performance in absorbing CO2. Ionic liquids have the advantages of good thermal stability, very low saturation vapor pressure, and designable structure, and are a new type of CO2 adsorbent, but ionic liquids have high viscosity themselves. Combining ionic liquids with organic or inorganic porous materials to form loaded ionic liquid materials, which can be used as CO2 adsorbent not only to improve the separation effect, but also to avoid the problem of high viscosity caused by direct absorption of ionic liquids, thus improving CO2 adsorption efficiency.

Spontaneous and Ion-Specific Formation of Inverted Bilayers at Air/Aqueous Interface.

Developing better separation technologies for rare earth metals, an important aspect of a sustainable materials economy, is challenging due to their chemical similarities. Identifying molecular-scale interactions that amplify the subtle differences between the rare earths can be useful in developing new separation technologies. Here, we describe the ion-dependent monolayer to inverted bilayer transformation of extractant molecules at the air/aqueous interface. The inverted bilayers form with Lu3+ ions but not with Nd3+. By introducing Lu3+ ions to preformed monolayers, we extract kinetic parameters corresponding to the monolayer to inverted bilayer conversion. Temperature-dependent studies show Arrhenius behavior with an energy barrier of 40 kcal/mol. The kinetics of monolayer to inverted bilayer conversion is also affected by the character of the background anion, although anions are expected to be repelled from the interface. Our results show the outsized importance of ion-specific effects on interfacial structure and kinetics, pointing to their role in chemical separation methods.

High-precision measurements of Mo isotopes by N-TIMS

We have developed a new high-precision analytical method for measuring molybdenum (Mo) isotopes by negative thermal ionization mass spectrometry (N-TIMS). This method represents an improvement over existing methods, thanks to a new chemical separation method that yields a better purification of the Mo fraction. In addition, we have used a multi-dynamic method for data collection with three different magnet settings to avoid being sensitive to drifts in Faraday cup efficiencies. Our method resulted in a more reliable thermal emission of MoO3- for a given run and we have obtained Mo isotope ratios measured on a series of 26 standards with the following reproducibilities (2 SD): ±6.1, ±5.8, ±2.9, and ±9.6 ppm for 94Mo/96Mo, 95Mo/96Mo, 97Mo/96Mo, and 100Mo/96Mo, respectively. This represents an improvement by a factor of 2–3 compared with previously published methods, using N-TIMS or MC-ICPMS. This new analytical method will have applications in the field of cosmochemistry (nucleosynthetic anomalies), environmental geochemistry or nuclear forensics (mass-independent fractionation).

Adsorption of Cr (VI), and Pb (II) from aqueous solution by 1-Butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide functionalized biomass Hazel Sterculia (Sterculia Foetida L.)

Biomass functionalization using a green solvent (ionic liquids-IL) is a new technology for water remediation. When sorbent materials are functionalized with green solvents or ionic liquids, the load of chemical separation methods is greatly reduced and recovery of ILs is facilitated. The purpose of this study is to determine the ability of an ionic liquid activated Hazel Sterculia foetida L. (HS) seed-based sorbent to remove Cr (VI) and Pb (II) from aqueous streams under enhanced ambient conditions. When compared to the raw HS, the IL functionalization of the adsorbent significantly improved the surface characteristics, i.e., increased surface area. Subsequently, the adsorption behavior of HS-IL was examined in detail for Cr (VI) and Pb (II), taking into account the effects of pH (2–10), contact time (0–300 min), speed (100–500 rpm), starting concentrations (10–100 mg/L), and temperature (303–323 K). Additionally, the adsorption processes of Cr (VI) and Pb (II) were fully evaluated using the Langmuir, Freundlich, Sips, and Toth two-and three-parameter models. When HS + IL was compared to HS (qm = 29.2 mg/g for Cr (VI); qm = 36.4 mg/g for Pb (II), the Langmuir isotherm model predicted a maximum adsorption capacity of qm = 82.9 mg/g (Cr(VI)); 108.63 mg/g (Pb (II)). Furthermore, kinetic modeling investigations demonstrated that the adsorption of Cr (VI), Pb (II) was better suited to a pseudo-second order model (R2 > 0.99). Moreover, the desorbing agents HCl and NaOH recovered the adsorbent (HS, HS-IL) from Cr (VI) and Pb (II) metal solutions, respectively. Finally, the reusability of the adsorbent (HS-IL) shows promise for Pb (II) up to six cycles and three Cr (VI) cycles.

Quantification of Re and four other trace elements (Ag, Cd, Pd, Zn) in certified reference materials and natural waters

We report a simple chemical separation method (i.e., single column and single elution) using an anion exchange resin (1-X8) to quantify Re and four co-eluted elements (Ag, Cd, Pd, Zn) from fresh and seawater matrices.

Anticancer Effects and Molecular Target of Theaflavins from Black Tea Fermentation in Vitro and in Vivo.

Black tea is one of the most popular beverages in the world, and numerous epidemiological studies have shown that drinking black tea is good for health. As a natural tea pigment formed during the fermentation of black tea, the content of theaflavins accounts for only 2-6% of the dry weight of black tea, but they have a great impact on the color and taste of black tea soup. Recently, a large number of studies have shown that theaflavins have a significant anticancer effect. In this Perspective, we first state the physical and chemical properties, separation and purification methods, and biological formation pathways of theaflavins and analyze their safety and oral bioavailability and the structure-activity relationship of their antioxidant and anticancer activities; then, we describe in detail their anticancer effect in vitro and in vivo and highlight their various molecular targets involved in cancer inhibition. The anticancer molecular targets of theaflavins are mainly cell-cycle regulatory proteins, apoptosis-related proteins, cell-migration-related proteins, and growth transcription factors. Finally, the possibility of developing new health-care food based on theaflavins is discussed. This Perspective is expected to provide a theoretical basis for the anticancer application of theaflavins in the future.

A Method to Separate Two Main Antioxidants from Lepidium latifolium L. Extracts Using Online Medium Pressure Chromatography Tower and Two-Dimensional Inversion/Hydrophobic Interaction Chromatography Based on Online HPLC-DPPH Assay

Free radicals, including 1,1-diphenyl-2-picrylhydrazyl, mediate oxidative stress to cause many chronic diseases (including cardiovascular diseases, diabetes and cancer). The extract of traditional Tibetan medicine Lepidium latifolium L. (L. latifolium) was reported to have free radical inhibition ability. Therefore, a system method was established to separate the ethanol extract of L. latifolium to prepare two main antioxidant compounds. First of all, silica gel and a medium-pressure liquid chromatography tower were used for pre-treatment of the ethanol extract of L. latifolium to obtain the main antioxidant active component fraction 4 through online high-performance liquid chromatography-1,1-diphenyl-2-picrylhydrazyl (HPLC-DPPH) assay. Then, fraction 4-1 was obtained by one-dimensional preparation using Megres C18 chromatographic column, and two active compounds with IC50 values 59.9 and 71.3 μg/mL were obtained by two-dimensional preparation using Click XIon chromatographic column. Through the study of the chemical components and separation methods of L. latifolium, the combination of HPLC-DPPH assay and two-dimensional preparative liquid chromatography was realized, providing a reference for the separation of active compounds from L. latifolium.

Plutonium isotopes and radionuclides in corals around Weizhou land in Beibu Gulf, China

Plutonium isotopes in the coral were determined with chemical separation method using AG 1-X8 and AG-MP-1M anion exchange resins and sector field inductively coupled plasma mass spectrometry (SF-ICP-MS) in order to elucidate the activity concentration and source of Pu around Weizhou land in Beibu Gulf, China. Furthermore, the activity concentrations of other radionuclides (238U, 226Ra, 232Th, 137Cs, 40K and 210Pb) were measured by a HPGe spectrometer. The activity concentration of 240+239Pu in the coral is determined to be in the range of 8.95–27.84 mBq/kg. The 240Pu/239Pu atom ratios in the samples range from 0.173 to 0.225, indicating that the main source of plutonium in this area is global fallout while the contribution of PPG is about 30%. Further, the activity concentrations of 238U, 232Th, 40K and 226Ra are determined to be in the range of 18.72–64.63, 1.37–20.8, 29.78–72.52 and 3.48–61.97 Bq/kg, respectively.