Application Of Separation Technology Research Articles

Flexible, durable, and anti-fouling maghemite copper oxide nanocomposite-based membrane with ultra-high flux and efficiency for oil-in-water emulsions separation

In this study, we developed a novel nanocomposite-based membrane using maghemite copper oxide (MC) to enhance the separation efficiency of poly(vinyl chloride) (PVC) membranes for oil-in-water emulsions. The MC nanocomposite was synthesized using a co-precipitation method and incorporated into a PVC matrix by casting. The resulting nanocomposite-based membrane demonstrated a high degree of crystallinity and well-dispersed nanostructure, as confirmed by TEM, SEM, XRD, and FT-IR analyses. The performance of the membrane was evaluated in terms of water flux, solute rejection, and anti-fouling properties. The pinnacle of performance was unequivocally reached with a solution dosage of 50 mL, a solution concentration of 100 mg L−1, and a pump pressure of 2 bar, ensuring that every facet of the membrane’s potential was fully harnessed. The new fabricated membrane exhibited superior efficiency for oil–water separation, with a rejection rate of 98% and an ultra-high flux of 0.102 L/m2 h compared to pure PVC membranes with about 90% rejection rate and an ultra-high flux of 0.085 L/m2 h. Furthermore, meticulous contact angle measurements revealed that the PMC nanocomposite membrane exhibited markedly lower contact angles (65° with water, 50° with ethanol, and 25° with hexane) compared to PVC membranes. This substantial reduction, transitioning from 85 to 65° with water, 65 to 50° with ethanol, and 45 to 25° with hexane for pure PVC membranes, underscores the profound enhancement in hydrophilicity attributed to the heightened nanoparticle content. Importantly, the rejection efficiency remained stable over five cycles, indicating excellent anti-fouling and cycling stability. The results highlight the potential of the maghemite copper oxide nanocomposite-based PVC membrane as a promising material for effective oil-in-water emulsion separation. This development opens up new possibilities for more flexible, durable, and anti-fouling membranes, making them ideal candidates for potential applications in separation technology. The presented findings provide valuable information for the advancement of membrane technology and its utilization in various industries, addressing the pressing challenge of oil-induced water pollution and promoting environmental sustainability.Graphical

The Effectiveness of Polyvinylidene Fluoride Membranes Modified with Poloxamer and Single/Multi-Walled Carbon Nanotubes for Lactalbumin Purification

The application of separation technology using ultrafiltration/nanofiltration membranes for protein purification and concentration has grown rapidly in the last decade. Innovations to synthesize membranes with properties and performance that suit the characteristics of the feed solution have been and will keep developing. This study aims to examine the strategies to improve the performance of the Polyvinylidene Fluoride (PVDF) membrane for lactalbumin protein isolation. The PVDF polymer membrane was modified by adding Poloxamer 188 (Po1) copolymer and a combination of two types of nanocarbons, i.e., single-walled carbon nanotubes (S-CnT) and multi-walled carbon nanotubes (M-CnT). The following membrane characteristics were examined: mechanical properties, morphological structure, porosity, elemental composition and functional groups, and surface hydrophilicity. The membrane’s filtration performance was analyzed in terms of its ability to pass water (flux) and concentrate lactalbumin protein. The results showed that the changes in the membrane morphological structure were clearly visible in the SEM test, which exposed more open membrane pores after adding Pol and S-CnT/M-CnT additives. The mechanical properties of the membrane also increased, as indicated by the increase in the tensile strength from 12.1 MPa to 16.07 MPa. In general, it was found that the composition of the PVDF/Pol/S-CnT/NMP polymer solutions resulted in better filtration performance compared to the membranes made of only the PVDF/NMP polymer solution.

Applications of separation technology in novel coronavirus research, epidemic prevention and detection

新型冠状病毒肺炎(COVID-19)疫情的爆发给世界公共卫生安全带来前所未有的挑战。随着新型冠状病毒(SARS-CoV-2)相关研究的不断深入,众多分析检测技术相继被应用,推动了病毒检测、疫苗和创新疗法的研发,从而使疫情早日得到控制。分离技术作为生命科学、医学、药学领域的关键技术,操作简单,分离效率高,选择性强,在新型冠状病毒的分离、检测、诊疗及防疫中起到不可替代的作用。该文以SARS-CoV-2或COVID-19为关键词在ISI Web of Science中进行主题检索,归纳了2020年度新型冠状病毒相关的研究论文,简要介绍主要的研究方向,并对国际顶级学术期刊Nature, Science, Cell的论文发表情况进行了统计。通过检索影响因子较高的期刊,综述了新型冠状病毒研究中主要应用的分离技术,并从亲和色谱和尺寸排阻色谱、液相色谱、磁珠分离、离心、微纳分离以及电泳6个方面进行说明。综述统计了亲和色谱和尺寸排阻色谱纯化的病毒相关蛋白,并介绍了其在新型冠状病毒传播、感染机制以及药物筛选中的应用;介绍了液相色谱对病毒候选药物评估以及复杂基质中单一成分的鉴定;介绍了磁珠分离在细胞分离、核酸提取和免疫学检测中的应用;介绍了离心对病毒颗粒、细胞以及血清的分离;介绍了微纳分离结合其他技术以实现病毒蛋白的高灵敏检测;简要介绍了电泳在聚合酶链式反应(PCR)产物分析中的应用。该文综述了2020年度新型冠状病毒研究和防疫检测中分离技术的应用情况,分析了分离技术在新型冠状病毒检测中发挥的作用,旨在为从事分离研究的科研工作者提供一些参考。

Extraction and carrier mediated transport of urea using noncyclic receptors through liquid membrane systems

Extraction and carrier mediated transport through bulk liquid membrane and supported liquid membrane systems have wide applications in separation technology. This paper highlights the use of six noncyclic receptors (podands) having variations in chain length and end group for the removal of urea using liquid membrane system. These receptors R1, R2, R3, R4, R5, R6 are diethylene glycol dimethyl ether, diethylene glycol dibutyl ether, diethylene glycol dibenzoate, diethylene glycol, triethylene glycol and tetraethylene glycol respectively. The sequence of extraction and transport of urea by BLM system using various receptors is R2 > R3 > R1 > R4 > R5 > R6 and R6 ≈ R3 > R5 > R4 > R1 > R2 respectively. Receptor R2 containing butyl end group is best extractant while receptor R6 with flexible backbone is best carrier and this carrier efficiency is used to remove urea using BLM system from the feed phase by recyclization process up to 88.16%. The experimental results influenced by concentration of receptors and urea. Effect of time was also studied.

A Review on Porous Polymeric Membrane Preparation. Part II: Production Techniques with Polyethylene, Polydimethylsiloxane, Polypropylene, Polyimide, and Polytetrafluoroethylene.

The development of porous polymeric membranes is an important area of application in separation technology. This article summarizes the development of porous polymers from the perspectives of materials and methods for membrane production. Polymers such as polyethylene, polydimethylsiloxane, polypropylene, polyimide, and polytetrafluoroethylene are reviewed due to their outstanding thermal stability, chemical resistance, mechanical strength, and low cost. Six different methods for membrane fabrication are critically reviewed, including thermally induced phase separation, melt-spinning and cold-stretching, phase separation micromolding, imprinting/soft molding, manual punching, and three-dimensional printing. Each method is described in details related to the strategy used to produce the porous polymeric membranes with a specific morphology and separation performances. The key factors associated with each method are presented, including solvent/non-solvent system type and composition, polymer solution composition and concentration, processing parameters, and ambient conditions. Current challenges are also described, leading to future development and innovation to improve these membranes in terms of materials, fabrication equipment, and possible modifications.

Polymeric membranes derived from immiscible blends with hierarchical porous structures, tailored bio-interfaces and enhanced flux: Potential and key challenges

The review article presented here comprehensively highlights the various fundamental aspects of polymer blends from molecular level miscibility to the evolution of bi-phasic morphology, under different processing conditions, that are essential for exploring their potential in membrane applications. It also compares and contrasts the existing practices in membrane development such as phase inversion, track etching etc., for alternative and economical strategies to develop novel membranes. The key role of rheology on the evolution of morphology during processing and post-processing operations such as compression molding, annealing etc. has been discussed under the framework of different techniques for the preparation of thin membranes. The different hierarchical porous structures (micro and nano), developed by selectively etching one of the components from binary blends, and their application in separation technology have been highlighted and the results have been compared against the existing solutions. The effect of various processing parameters and ratio of the blend component that decides the final morphology of the membrane has been discussed. The unimpeded permeation of fluids is discussed with respect to the different morphology that is generated during their fabrication and the reasons for their clogging, fouling etc. have been extensively discussed. Further, different strategies like in situ and ex situ strategies modification of the membrane surface have been discussed with respect to antibacterial and antifouling properties. The efficacies of various in situ and ex situ strategies to render the surface antibacterial is elaborated with respect to water purification applications.

ChemInform Abstract: Host—Guest Chemistry in Two‐Dimensional Supramolecular Networks

AbstractReview: 119 refs.

Highly efficient and multidimensional extraction of targets from complex matrices using aptamer-driven recognition

Adsorbents are widely employed in both fundamental and applied research areas such as separation technology, biotechnology, and environmental science. Selectivity and reusability are two most important requirements for adsorbents. Aptamers exhibit perfect selectivity and easy regeneration, which make them uniquely effective adsorption materials. Herein, we have rationally designed novel aptamer-based adsorbents and investigated their performance in extraction/separation of targets from an aqueous solution. These adsorbents can selectively extract targets from complicated sample matrices containing background compounds. Moreover, they can also be easily recycled without a significant loss of adsorption capacity. Notably, the adsorbents did not affect the activity of isolated biological samples, revealing their potential for the purification/separation of biomolecules. Composite adsorbents were constructed using aptamer-based adsorbents and a porous polymer, displaying highly efficient target separation from aqueous solution. Finally, separation columns were constructed, and targets in the aqueous solution were efficiently separated by these columns. The aptamerbased adsorbents described here exhibit great promise for potential applications in separation technology, biotechnology, and environment-related areas.

Protein kinase inhibitor analysis with the core–shell separation technique

Here, we describe the application of the core-shell separation technology in the field of protein kinase inhibitor analysis with the HPLC-diode-array detector (DAD) technique. A Kinetex 2.6 μm C8 100 Å, 150 × 4.6 mm column maintained at 30 ± 1 °C was used for the separation, and further, a connection of two core-shell HPLC columns with a total column dimension of 250 × 4.6 mm was also applied. The analytes were eluted with a mobile phase consisting of 0.05 M H(3)PO(4)/KH(2)PO(4) (pH = 2.3)-acetonitrile (7:3, v/v), with a flow rate of 0.7 mL/min. A liquid-liquid extraction with 1-chlorobutane was used for the sample preparation. The validation of the canertinib analytical method resulted in recoveries in the range of 74-79 % and in relative standard deviation and accuracy lower than 15 %, both for between- and within-batch calculations. A very good linearity in the validated range (5-10,000 ng/mL) and a limit of quantification (LOQ) of 5 ng/mL were achieved. Peak width, height and peak area of six protein kinase inhibitors analysed with a core-shell column and with a conventional fully porous particle column were compared. The results showed that, for most inhibitors analysed with the core-shell analytical column, the peaks were about two to three times narrower and two to three times higher, with areas that remained almost unchanged. The presented study revealed that the application of this separation technology is a very cost-effective way to bring the LOQ of the protein kinase inhibitor analysis with an HPLC closer to the possibilities of the LC-MS/MS technique.

초임계유체 공정과 분리기술의 응용

초임계유체 공정과 분리기술의 응용

Purification of α‐amylase from human saliva by superparamagnetic particles

AbstractBACKGROUND: Several studies of magnetic carrier technology have focused on the application of separation technology, because the magnetic support can separate the target from the reaction medium by application of a magnetic field and because the magnetic carrier can be easily recovered. In the present study, superparamagnetic iron oxide (SPIO) modified by epichlorohydrin was employed as a support whose surface could be coated with starch. The starch‐coated support was used for isolating human salivary amylases.RESULTS: The results showed that the starch‐SPIO support could isolate amylases from human saliva with 91.1% recovery and 3.5‐fold purification to high specific activity. Sodium dodecyl sulfate polyacrylamide gel electrophoresis revealed that the purifed amylase comprised two isoamylases with estimated molecular weights of 55 and 59 kDa. The activities of crude and purified amylases showed optimal pH values of 6–7 and 7 and optimal temperatures of 40 and 30 °C respectively. The thermal stability range for both crude and purified amylases was between 20 and 40 °C.CONCLUSION: The attachment of substrates to SPIO could offer a novel and efficient method for purifying enzymes either as an initial step prior to further purification or as a final step for diagnostic usage. Copyright © 2009 Society of Chemical Industry

Physical properties of microporous membranes prepared by hydrolyzing cellulose/soy protein blends

Microporous membranes (CS1- n) were prepared by blending cellulose and soy protein isolate (SPI) in 6 wt.% NaOH/5 wt.% thiourea aqueous solution. The membranes CS1- n were hydrolyzed with 5 wt.% NaOH aqueous solution to obtain membranes CS2- n. The structure and properties of the membranes were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy (SEM), the flow rate method, and tensile testing. The blend membranes CS1- n exhibited mesh structure woven by SPI and cellulose, and the membranes CS2- n possess microporous structure as a result of the removal of SPI during the NaOH-hydrolysis process. The apparent pore size (2 r e) measured with SEM, the mean pore size (2 r f) obtained by the flow rate method, and the water ultrafiltration rate (UFR) of the CS1- n and CS2- n membranes increased with an increase in SPI content, and are higher than those of the pure cellulose membrane and previous membranes. The values of 2 r f (47.7–77.2 nm) and UFR (28–53.5 mL h −1 m −2 mmHg −1) of the microporous membranes CS2- n are higher than those of the corresponding membranes CS1- n, because of removing of most of SPI by NaOH-treatment. The microporous membranes also kept high tensile strength in both dry and wet states. In addition, the membranes CS2- n containing a small amount of SPI are suitable for the culture of Vero cells. Therefore, the membranes could be used as candidates for application in separation technology and biomedical fields.

Synthesis of nano-sized metal oxide powders and their application in separation technology

Nano-sized inorganic oxides that find application in various fields (such as, in catalysis, sensors, pigments, membranes etc.) are also reported to be excellent reagents in various separation technologies through selective adsorption. Depending on the chemistry of the constituent atoms, they are known to exhibit remarkable adsorption properties due to their enhanced surface area and large interface volume. The nano-sized inorganic oxides can be produced by various reported physical and chemical methods. In general, the chemical methods offer the advantages of easy preparation of nearly any composition, maintaining compositional homogeneity and high purity. However, the chemical routes generally involve complex techniques and an improved level of skill is required to realize the benefits. We have been successful in standardizing the preparation of a variety of nano-sized inorganic oxides through thermolysis of a polymeric based aqueous precursor solution of the desired inorganic ions. The developed method is less cumbersome, more versatile, more cost effective and hence economically more viable than the existing ones for large-scale production of nano-sized inorganic oxides. In this paper we present the preparation of nano-sized powders of Fe 3 O 4 , Al 2 O 3 and ZrO 2 . The obtained nano-sized oxide powders were sonicated in water and incorporated in the matrix of activated charcoal through adsorption. The oxide incorporated charcoal materials have been used as the adsorbing bed for the removal of trace amounts of fluoride/arsenite and arsenate ions from industrial wastewater and aldehyde from the perfume grade alcohols. The oxides have been prepared through thermolysis of precursor solutions that contained the respective cations homogeneously dispersed in the polymeric matrix of sucrose and polyvinyl alcohol. Calcination of the fluffy, carbonaceous precursor powder at 200-500°/2 h resulted in the desired inorganic oxide phase with particle diameters ranging between 20 and 38 nm and BET surface area ranging between 120 and 200 m 2 /g. The charcoal embedded fine powders of the inorganic oxides have been able to remove fluoride/ arsenite and arsenate ions from industrial wastewater upto 0.01-0.02 ppm levels. Many of the perfume grade alcohols are produced by reduction of aldehyde by M.P.V. reduction using aluminum alkoxid or catalytic reduction using hydrogen. However, a ppm amount of residual aldehydes are perpetually retained in the alcohol even through the most efficient reduction by the mentioned process and changes the flavour of the perfume formulations. Here we report an efficient separation of cinnamaldehyde from cinnamyl alcohol using nano-sized Fe 3 O 4 powders. For this, the adsorbing bed has been further modified by impregnating it with 3-aminopropyltriethoxysilane in ethanol medium. The amino groups impregnated in the matrix readily undergoes reaction with the adsorbed aldehydes and results in the formation of Schiff bases thereby reducing the concentration of residual aldehyde contained in the alcohol to levels <0.2 ppm. The prepared adsorbent has been also tested for the removal of heptaldehyde from heptanol and octaldehyde from octanol. The major advantage of the process is that the adsorbent and the adsorbed aldehyde can be easily separated by applying an external magnetic field, thus avoiding the filtration process.

Metal Oxide Containing Mesoporous Silica with Bicontinuous "Plumber's Nightmare" Morphology from a Block Copolymer-Hybrid Mesophase This work was supported by the National Science Foundation (DMR-0072009), the Cornell Center for Materials Research (NSF DMR-9632275), and the Department of Energy (DE-FG02-97ER62443). We also acknowledge very helpful discussions with G. E. S. Toombes.

Two distinct channel systems are present in a polymer–inorganic nanocomposite, the structure of which is based on a bicontinuous plumber's nightmare (a regular array of completely interconnected tubes; see picture). Calcination at high temperatures leads to a metal oxide containing mesoporous silica-type material with promise for application in separation technology and catalysis.

NUCLEAR FUEL CYCLE TECHNOLOGIES -SUSTAINABLE IN THE TWENTY FIRST CENTURY?

ABSTRACT This article discusses the application of separation technologies, in particular solvent extraction and ion exchange in the uranium nuclear fuel cycle. The history and decisions in selecting the technology are briefly discussed. The global trends in the energy sector are reviewed and the impact of other energy sources on the nuclear power industry both now and in the future is described. The effect of over capacity in uranium mining and milling, UOC refining and uranium enrichment on the development of new technology is a key feature of this article. Although over capacity is not the case with irradiated fuel reprocessing, other constraints limit the development of new technology and/or process improvements. The environmental considerations of all stages of the uranium nuclear fuel cycle will require better process technology and it is this key balance between the environmental and economic considerations that constitute a key component of this article. Some new solvent extraction processes that may offer a way forward to the segregation of actinides from highly active waste, integrated technologies and non aqueous systems are discussed.

Reverse osmosis separation for a montmorillonite membrane

It has been known for a long time that a membrane made of a pure clay rejects ionic solutes. Its application in separation technology, however, has never been attempted. This study is to explore such a possibility by investigating the solute separation characteristics of a montmorillonite membrane. For this purpose, a montmorillonite membrane with a thickness of 0.5 mm was prepared by sandwiching purified clay paste between two millipore filters and reverse osmosis experiments were conducted for various inorganic and organic solutes under an operating pressure of 3 MPa. The membrane exhibited characteristics typical for a charged membrane by rejecting sodium chloride solute less effectively with increasing solute concentration. The rejection of small organic solutes was very low. It was also found that the separation of amino acids greatly depends on the net charge carried by the amino acid molecule. Thus, this membrane opens up a route to the effective fractionation of electrolyte/nonelectrolyte mixtures and amino acid mixtures.