Article

Attapulgite: from clay minerals to functional materials

Authors:
  • Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences
  • Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, China
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Abstract

Attapulgite is a kind of natural one-dimensional nanomaterial. Attapulgite has unique nanorod-like crystals, nanochannels and reactive groups on the surface, and has been widely used in many fields including agriculture, chemical engineering, environmental protection, adsorption materials and composites. Recently, the disaggregation of the crystal bundles of attapulgite into mono-dispersed ones has been achieved, while keeping their environment-friendly property. This has changed attapulgite from clay mineral to a very interesting nanomaterial. With unique nanorods-like crystals and nanochannels, attapulgite can be used to prepare nanocomposites via the crystals and reactive groups on the surface, and also can be used to prepare hybrid materials via the nanochannels. Attapulgite is the new focus for the preparation of diverse functional materials. Thus, it is now pertinent to give an overview of the recent progress in the field. First, we hope to overview the structure and physicochemical properties of attapulgite. Subsequently, we will review the progress about disaggregation of the attapulgite crystal bundles and regulation of attapulgite structures. We will then focus on the development of attapulgite-based functional materials (e.g., adsorbents, colloidal materials, hybrid materials, polymer/attapulgite composites, bio-inspired materials, catalysts and energy materials) and recycling of attapulgite. In the conclusions, we will summarize the progress of attapulgite-based functional materials, and the challenges in the field. Overall, this review will hopefully promote the development of attapulgite and attapulgite-based functional materials, or even the clay-based ones.

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In last years, a plethora of extraction techniques has emerged as environmental-friendly alternatives to conventional extraction procedures. In this particular field, a novel class of solvents known as deep eutectic solvents (DES) has arisen as a new and very promising tool. Compared with conventional organic solvents, DES as well as the so-called natural deep eutectic solvents (NADES) have attracted considerable attention due to the fact that they not only are eco-friendly, non-toxic, and biodegradable organic compounds but also have a low cost, being easy to produce in the own laboratory. The present review provides a critical and organized overview of novel extraction techniques using DES as extracting solvents that were applied in food, biological and environmental sample analysis. An evaluation of how these DES/NADES could improve extraction yields of a variety of analytes and advantages and limitations of each proposal will be discussed and compared with earlier studies.
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Driven by the advent of fullerenes, carbon nanotubes and graphene, designing or tailoring sp²-rich carbon clusters in carbon based films attains very interesting properties which can be ideal in various applications. Depositing sp²-rich clusters evolve toward a three-dimensional arrangement (composed of extended, bent, and cross-linked graphite basal planes, i.e. fullerene-like carbon (FLC)) or nanocrystalline planar graphitic configurations with the promotion in size and ordering of six-membered ring clusters (i.e. graphite-like carbon (GLC)). However, the films are studied separately and their structure effects on sliding-induced structure changes has never enjoyed elaboration. Here we built the self-mated friction groups of single structural films coated at two sliding surfaces, and designed a smart device to gather the transformed products under different load and sliding cycles. Super-low friction was realized under higher load by low-shear strength from graphene formed at the GLC interface (0.005), or reduced contact area from spherical nanoparticles with outer graphite shells produced at the FLC interface (0.009), resulting by different rehybridization pathways from different film structures. The role of film and rehybridized structures under super-low friction contact was discussed. The results could enrich the understanding of friction-induced rehybridization mechanism and help to deposit suitable films to significantly reduce friction.
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Combination of transition metal catalysis with organocatalysis in ways of synergetic catalysis, cooperative catalysis, or/and sequential catalysis has been emerged as a powerful strategy to promote organic transformations that cannot be achieved by each individual independently. Herein, a new protocol for the synthesis of primary amides from olefins, CO and NH3 through one-pot tandem methoxycarbonylation-aminolys was presented over a bi-functional ligand (L1) based rhodium catalyst with functions of co-catalysis. L1 is composed of the phosphino-fragment and the amino-/imino- tautomeric moiety. Then L1-based Rh-catalytic system demonstrated a combination of Rh-P transition metal catalysis and the tautomeric catalysis. In this tandem methoxycarbonylation-aminolysis, NH3 also served as a ligand to work together with the phosphino-fragment to synergetically modify the performance of Rh-catalyst responsible for the first-step methoxycarbonylation of olefin to generate the esters, and the Rh-tailed tautomeric catalyst was in charge of the subsequent aminolysis to generate the targeted primary amides.
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In this study, we carried out the transition experiments of graphite-like (GL) to fullerene-like (FL) structures by placing high temperature steel substrates in the depositing environment which can form FL hydrogenated carbon films. We investigated the changes of bond mixtures, H content, aromatic clusters and internal stress at the transition process, and proposed the transformation mechanism inferred from Raman, TEM cross-section, FTIR and XPS results. It was found that the size of aromatic clusters and accordingly graphene planes and the formation of edge dangling bonds were the key steps. H⁺ bombardment leaded to the splitting of large graphene planes (at GL stage) into more and smaller planes (at FL stage) and the formation of edge dangling bonds; Some of these dangling bonds were reduced by the formation of pentagons and subsequent curving of the smaller planes, which were an indicator of FL structures.
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To circumvent the imbalances of electrochemical kinetic and capacity between Li+ storage anode and capacitive cathode for lithium ion capacitors (LICs), we herein, demonstrate an efficient solution by boosting the capacitive charge storage contributions of carbon electrode to construct a high performance LIC. Such a strategy is achieved by in-situ and highly doping nitrogen atoms into carbon nanospheres (ANCS), which increases the carbon defects/active sites, inducing more rapidly capacitive charge-storage contributions for both Li+ storage anode and PF6- storage cathode. High level N doping induced capacitive enhancement is successfully evidenced by constructing a symmetric supercapacitor using commercial organic electrolyte. Coupling a pre-lithiated ANCS anode with a fresh ANCS cathode enables a full-carbon LIC with a high operation voltage of 4.5 V and high energy/power densities thereof. The assembled LIC device delivers high energy densities of 206.7 Wh kg-1 and 115.4 Wh kg-1 at power densities of 225 W kg-1 and 22.5 kW kg-1, respectively, as well as an unprecedented high-power cycling stability with only 0.0013% capacitance decay per cycle within 10000 cycles at a high power-output of 9 kW kg-1.
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The paper presents a new procedure for the determination of organic acids in a complex aqueous matrix using ultrasound-assisted dispersive liquid–liquid microextraction followed by injection port derivatization and GC–MS analysis. A deep eutectic solvent (choline chloride: 4-methylphenol in a 1:2 mol ratio) was used both as an extracting solvent and as a derivatizing agent to yield ion pairs which were next converted to methyl esters of organic acids in a hot GC injection port. The procedure was optimized in terms of selection of a deep eutectic solvent, disperser solvent, and the ratio of their volumes, pH, salting out effect, extraction time, injection port temperature and time of opening the split valve. The developed procedure is characterized by low LOD (1.7–8.3 μg/L) and LOQ (5.1–25 μg/L) values, good repeatability (RSD ranging from 4.0 to 6.7%), good recoveries for most of the studied analyte (81,5–106%) and a wide linear range. The procedure was used for the determination of carboxylic acids in real effluents from the production of petroleum bitumens. A total of ten analytes at concentrations ranging from 0.33 to 43.3 μg/mL were identified and determined in the effluents before and after chemical treatment. The study revealed that in effluents treated by hydrodynamic cavitation an increase in concentration of benzoic acid and related compounds was observed.
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The Namib Desert beetle-Stenocara can adapt to the arid environment by its fog harvesting ability. A series of samples with different topography and wettability that mimicked the elytra of the beetle were fabricated to study the effect of these factors on fog harvesting. The superhydrophobic bulgy sample harvested 1.5 times the amount of water than the sample with combinational pattern of hydrophilic bulgy/superhydrophobic surrounding and 2.83 times than the superhydrophobic surface without bulge. These bulges focused the droplets around them which endowed droplets with higher velocity and induced the highest dynamic pressure atop them. Superhydrophobicity was beneficial for the departure of harvested water on the surface of sample. The bulgy topography, together with surface wettability, dominated the process of water supply and water removal.
Article
Superhydrophobic coating have presented enormous application value in mechanical, architectural and other engineering in decade. However, there are some problems that we have to envisage, such as weak mechanical strength, complex technologies and toxic modifiers, which greatly limits its applications in real-life. Here, an omnipotent robust silicon dioxide @ epoxy resin coating was successfully prepared by a facile and environment friendly process, and the whole process can be accomplished in a beaker without any usage of toxic reagents. The as-prepared coating presents excellent waterproof ability, mechanical stability, long-time stability and can be coated almost on any solid substrates. What is more, the superhydrophobic coating also exhibits better survivability to face various intricate environments in nature such as windy, dusty, icing and torridity. Hence, this omnipotent silicon dioxide @ epoxy resin coating possesses enormous application potential in many fields and the facile and environment friendly productive process gives it possibility to be quantity produced in industry.
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In this work, for the first time, ferrofluid of magnetic montmorillonite nanoclay and deep eutectic solvent was prepared and coupled with directly suspended droplet microextraction. Incorporation of ferrofluid in a miniaturized sample preparation technique resulted in achieving high extraction efficiency while developing a green analytical method. The prepared ferrofluid has strong sorbing properties and hydrophobic characteristics. In this method, a micro-droplet of ferrofluid was suspended into the vortex of a stirring aqueous solution and after completing the extraction process, was easily separated from the solution by a magnetic rod without any operational problems. The predominant experimental variables affecting the extraction efficiency of explosives were evaluated. Under optimal conditions, the limits of detection were in the range 0.22-0.91 µg L-1. The enrichment factors were between 23 and 93 and the relative standard deviations were< 10%. The relative recoveries were ranged from 88 to 104%. This method was successfully applied for the extraction and preconcentration of explosives in water and soil samples, followed their determination by high performance liquid chromatography with ultraviolet detection (HPLC-UV).
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In this research, a new vortex assisted dispersive liquid−liquid microextraction based on the freezing of deep eutectic solvent (VADLLME−FDES) has been developed for the determination of organic mercury (R-Hg) and inorganic mercury (Hg²⁺) in blood samples prior to their analysis by graphite furnace atomic absorption spectrometry (GFAAS). In this method, a green solvent consisting of 1-octyl-3-methylimidazolium chloride and 1-undecanol was used as an extraction solvent, yielding the advantages of material stability, low density, and a suitable freezing point near room temperature. Under the optimum conditions, enrichment factor is 112. The calibration graph is linear in the range of 0.30–60 µg L⁻¹ and limit of detection (LOD) is 0.10 µg L⁻¹. Repeatability and reproducibility of the method based on seven replicate measurements of 5.0 µg L⁻¹ of Hg²⁺ in analyzed samples were 3.7% and 6.2%, respectively. The relative recoveries of blood samples which have been spiked with different levels of Hg²⁺ are 90–109%. A new deep eutectic solvent consists of two parts: [DMIM]Cl and 1-undecanol in the molar ratio of 1–2. The accuracy of the proposed procedure was also assessed by determining the concentration of the mercury in a standard reference material. All organic mercury (R-Hg) species were converted to Hg²⁺ and finally, the concentration of R-Hg is simply calculated by mathematically subtracting the concentrations of Hg²⁺ from the concentration of total mercury (t-Hg). The extraction methodology is simple, rapid, cheap and green since small amounts of non-toxic solvents are necessary.
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Deep eutectic solvent based on L-proline and oxalic acid has been demonstrated for the first time as an efficient catalyst for synthesis of 4, 7-dihydro-1H-pyrazolo[3, 4-b] pyridine-5-carbonitrile derivatives via one-pot three-component reaction of aldehyde, 3-oxopropanenitrile and 1H-pyrazol-5-amine. The key features of this approach include the broad substrate scope, operational simplicity, recyclable catalyst and possibility to scale up giving multigram quantities.
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The superhydrophobic paper containing CMC, HAP and ZnO was prepared by a novel and facile method with eco-environmental and modifier-free process. The superhydrophobic property is effectively controlled by different amount of ZnO, which might be effect of surface roughness of the paper. Except for the common performances, such as self-cleaning property, chemical durability and mechanical abrasion durability, the excellent thermal stability and anti-bacterial properties will dramatically extend the practical applications of the paper. In addition, such paper still maintains its superhydrophobicity after flammable oil adsorption-combustion, further validating its excellent fire-resistant property. The combination of superhydrophobicity and flame retardancy can largely enhance the durability of the paper. These characteristics make the multifunctional paper a better candidate than the commercial paper, which may be a breakthrough in paper-making industries.
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It is challenging for flexible solid‐state hybrid capacitors to achieve high‐energy‐high‐power densities in both Li‐ion and Na‐ion systems, and the kinetics discrepancy between the sluggish faradaic anode and the rapid capacitive cathode is the most critical issue needs to be addressed. To improve Li‐ion/Na‐ion diffusion kinetics, flexible oxygen‐deficient TiO2−x/CNT composite film with ultrafast electron/ion transport network is constructed as self‐supported and light‐weight anode for a quasi‐solid‐state hybrid capacitor. It is found that the designed porous yolk–shell structure endows large surface area and provides short diffusion length, the oxygen‐deficient composite film can improve electrical conductivity, and enhance ion diffusion kinetic by introducing intercalation pseudocapacitance, therefore resulting in advance electrochemical properties. It exhibits high capacity, excellent rate performance, and long cycle life when utilized as self‐supported anodes for Li‐ion and Na‐ion batteries. When assembled with activated carbon/carbon nanotube (AC/CNT) flexible cathode, using ion conducting gel polymer as the electrolyte, high energy densities of 104 and 109 Wh kg−1 are achieved at 250 W kg−1 in quasi‐solid‐state Li‐ion and Na‐ion capacitors (LICs and SICs), respectively. Still, energy densities of 32 and 36 Wh kg−1 can be maintained at high power densities of 5000 W kg−1 in LICs and SICs. The designed TiO2−x/CNT//AC/CNT hybrid capacitors integrate the advantages of (1) large surface area and short diffusion length, (2) enhanced Na‐ion diffusion kinetics and ultrafast ion/e− transport network, (3) flexible and light‐weight features, and (4) better safety from quasi‐solid‐state electrolyte, therefore maximum energy densities of 104 and 109 Wh kg−1 are achieved in Li‐ion and Na‐ion capacitors, respectively.
Article
It maintains as a challenging topic for N-monomethylamine synthesis as the N,N-dimethylation reaction is thermodynamically favorable. The kinetically controlled N-monomethylamine synthesis from nitroarene and paraformaldehyde/H2 is reported with super-high N-monomethylamine selectivity in the presence of a Pd/TiO2 catalyst. The superior selectivity should be attributed to the preferential adsorption of the primary amine over N-monomethylamine on the Pd/TiO2 surface, as elucidated by NH3/Me2NH-TPD, while the nice catalytic activity could be associated to the good H2 activation ability and high amine adsorbing capacity of the catalyst, as elucidated by NH3-TPD and H2-TPR tests. Good results were obtained with a variety of nitroarenes containing methyl, methoxyl, hydroxyl, fluoride, trifluoromethyl, ester, and amide substituents as starting materials, and the potential synthetic utility of this protocol in pharmaceutical is illustrated by N-monomethylation of drug molecules, such as clinidipine, nimesulide, procaine and methyl aminosalicylate.
Article
2D transition metal carbide materials called MXene have attracted great interests in the field of electrochemical energy storage due to their high electrical conductivity and high volumetric capacity. However, the low capacity accompanied by sluggish sodiation kinetics of electrode made from multilayer MXene has limited their further application for sodium ion storage. The key challenge to overcome the above issue is to decrease the Na+ diffusion barrier and increase active site concentration in MXene electrode. In this work, a method to significantly improve the capacity and kinetic of Ti3C2 MXene for Na+ storage by facile alkali metal ion pillaring is reported. After Na+ pillaring, the MXene sheets (Na-Ti3C2) with incremental interlayer spacing exhibits delivers a high reversible capacity of 175 mAh g-1 (~170% of the origin) at 0.1 A g-1 and excellent cycling stability for 2000 cycles at 2.0 A g-1 for sodium ion storage. Combing ex-situ XPS with kinetics analysis, more active sites and lower Na+ diffusion barrier can be confirmed after Na+ pillaring than Ti3C2, Li-Ti3C2, and K-Ti3C2. The role of terminal groups (-OH) in Na-Ti3C2 has also been confirmed by analyzing the electrochemical performance of annealed Na-Ti3C2 samples (450ºC and 700 ºC). The results show that the existence of –OH groups in Na-Ti3C2 can increase Na+ storage active sites, but decrease the Na+ storage kinetics. Coupling the Na-Ti3C2 anode with activated carbon (AC) cathode, the assembled sodium-ion capacitor (SIC) delivers a high energy density of 80.2 Wh kg-1 and high power density (6172 W kg-1) with an ultra-long and stable cycling performance (capacity retention: ~78.4 at 2 A g-1 after 15000 cycles).
Article
Active carbon with hierarchical pore structure (HPC) is massively prepared using asphalt as carbon precursor, by a template directed method. The as‐prepared HPC exhibits excellent capacitive energy‐storage capacities on symmetric supercapacitor (140 F g‐1 at 0.5 A g‐1) and Li ion capacitor (LIC) using HPC as both cathode and anode (340 F g‐1 at 0.5 A g‐1), as well as ultralong cyclability for supercapacitor (no capacity loss after 15000 cycles) and LIC (91.3% capacitance retention after 10000 cycles). The superior energy density and power density are 202 W kg‐1 and 15398 Wh kg‐1 respectively. The hierarchical pore structure coordinate with the existence of heteroatoms that originated from carbon precursor are conducive to the delivery of the electrolyte ions and electrons, greatly contributing to the high capacitance and the excellent cycle performance. The work provides a very promising opportunity for high capacitive energy storage devices by means of the high value‐added utilization of the asphalt.
Article
Stainless steel (SS) have been widely used in marine structures and food industry due to its high corrosion resistance and excellent mechanical strength. Marine structures such as ships, ocean engineering and offshore rigs, are easily attacked by crude oil generated by oil spills and SS vessels applied in food industry are fouled by the organic matters in the fluid. Here, fish-scale-like SS surfaces with superhydrophilic and underwater superoleophobic property, including 316 L SS mesh and 304 SS plate, are designed by a facile chemical-based oxidation method. The obtained SS surfaces show excellent underwater anti-crude-oil-fouling property and thermal stability. Furthermore, the obtained 316 L SS mesh can effectively separate crude oil/water mixture solely driven by gravity. Significantly, the as-prepared SS surfaces possess robust antifouling and self-cleaning property during multiple cycles with the aid of Fenton-like catalytic reaction between Fe (III) and H2O2 or calcination at high temperature. Therefore, the fish-scale-like SS surfaces show great potential in a wide range of fields, such as marine antifouling, oil-water separation and food industry.
Article
Transition metal sulfides/selenides are explored as advanced electrode materials for non-aqueous sodium-ion capacitors, using FeS2-xSex as an example. Solid solution of S/Se in FeS2-xSex allows it to combine the high capacity of FeS2 and the good diffusion kinetics of FeSe2 together, thereby exhibiting excellent cycle stability (~220 mAh g-1 after 6000 cycles at 2 A g-1) and superior rate capability (~210 mAh g-1 at 40 A g-1) within 0.8-3.0 V. These results are much better than those of FeS2 and FeSe2, confirming the advantages of S/Se solid solution as supported by EIS spectra, DFT calculations and electron conductivity. As FeS2-xSex is paired with activated carbon as Na-ion capacitors, this device is also better than sodium-ion batteries of FeS2-xSex//Na3V2(PO4)3 and sodium-ion capacitors of metal oxides//AC, particularly at high rates. These results open a new door for the applications of sulfides/selenides in another device of electrochemical energy storage.
Article
In this study, an air assisted liquid phase microextraction based on deep eutectic solvent (AA-DES-LPME) method was developed for separation, preconcentration and determination of lead followed by graphite furnace atomic absorption spectrometry (GFAAS). The complexation of Pb(II) was carried out by using 4-(2-thiazolylazo) resorcinol as complexing agent at pH 6. Deep eutectic solvent was prepared by using choline chloride phenol (ChCl-Ph) and was added to an aqueous solution containing analyte, and then mixture was sucked up and injected nine times with the help of a syringe, and a cloudy state was attained. After extraction, the solution was centrifuged and upper layer was separated and Pb(II) ions was determined by GFAAS. Different parameters were investigated and optimized including pH, volume and type of DES, effect of ligand volume, effect of pulling and pushing cycles. Under optimum conditions, the detection limit, limit of quantitation were observed as 0.60 ng L⁻¹ and 1.98 ng L⁻¹, respectively. Preconcentration factor (PF) and relative standard deviation (RSD) were found to be 60 and 2.9%, respectively. Certified reference materials (CRMs) were used to check the accuracy of developed technique. Finally, present procedure was fruitfully used for analysis of Pb(II) in various food and water samples.
Article
Superhydrophobic layers are extremely essential for protecting material surface in various applications. In this study, a stable superhydrophobic mixed matrix surface with a 152.2° contact angle can be fabricated through the technology of layer-by-layer hot-pressing (HoP), and then modified by 1H,1H,2H,2H-perfluorooctyltriethoxysilane (PFOTES) on the [email protected] fabric surface. The morphology and chemical composition were analyzed by the means of SEM, XRD and FTIR. The obtained superhydrophobic coatings showed excellent antiwear performance and drag reduction under desired working conditions. Moreover, we successfully applied superhydrophobic [email protected] fabric in the alcohol adsorbent with high removal capacity, and it can be reused for several times without serious efficiency loss.
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Two-dimensional (2D) MoSe2/graphene nanocomposites show great potential as anode materials for sodium ion batteries (SIBs). In this work, we report the controlled growth of oriented, interlayer-expanded MoSe2 nanosheets on graphene with Mo–C bonding via a surfactant-directed hydrothermal reaction. The resulting 2D nanocomposite with strong electronic coupling facilitates both electron and Na-ion transfer across the interface and reversible insertion/extraction of Na-ion, enabling fast pseudocapacitive Na-ion storage with reduced voltage hysteresis and excellent durability over 1500 cycles. Density Functional Theory (DFT) calculation demonstrated MoSe2/graphene established a charge accumulation at the interface and promoted sodium-ion transport through the interface. Such outstanding Na-ion storage capability propels their potential application in sodium-ion capacitors (SICs). As a proof-of-concept, a model hybrid SIC was demonstrated by assembling with MoSe2/graphene composite as anode and activated carbon as cathode, delivering an impressive energy density of 82 W h kg⁻¹ and power output of 10,752 W kg⁻¹ within a voltage window of 0.5–3 V. The SIC also delivered a superior rate capability (66% capacitance retention after increasing the current density from 0.1 to 25.6 A g⁻¹) and cyclability (81% capacitance retention over 5000 cycles at 5 A g⁻¹), which shows promise for bridging the performance gap between conventional batteries and supercapacitors. The proposed strategy based on hierarchical hybridization combined with chemical bonding and interlayer engineering may hold great promise for developing advanced electrode materials for next-generation clean energy systems.
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In this article, dicationic ionic liquids (DILs), including N,N,N,N′,N′,N′-hexaethyl-ethane-1,2-diammonium dibromide (HEDBr), N,N,N,N′,N′,N′-hexaethyl-propane-1,3-diammonium dibromide (HPDBr) and N,N,N,N′,N′,N′-hexaethyl-butane-1,4-diammonium dibromide (HBDBr), were designed and used to extract phenolic compounds from model oil and coal tar oil. The effects of stirring time, temperature, DIL:phenol mole ratio, and initial phenol concentration on the extraction of phenol were studied. It is found that the DIL:phenol mole ratio is only around 0.3 when the highest extraction efficiency of phenol is obtained. The extraction process completes within 5 min at room temperature, and the extraction efficiency is not dependent on temperature. Also, the ultimate phenol concentration remains constant despite the difference in initial phenol concentrations. Of these DILs, HPDBr shows the lowest ultimate phenol concentration of 3.9 g/dm³, and the extraction efficiency of phenol can reach as high as 97.0%. These DILs can be regenerated by anti-solvent method and reused several times without significant reduction in extraction efficiency. In addition, HPDBr was demonstrated to extract phenolic compounds from real coal tar oil, and its extraction efficiency of phenolic compounds is 92.7%. The mechanism, analyzed by FT-IR, shows that there is a hydrogen bond between phenol and DIL.
Article
Deep eutectic solvents (DESs) have naturally emerged as an alternative for traditional organic solvents for their efficiency on extracting natural products from plant materials. In the present study, 12 kinds of DESs (choline chloride as the hydrogen bond acceptor) were firstly prepared and applied to extract five main flavonoids (namely rutin, quercetin-3-O-glucoside, quercetin, kaempferol and isorhamnetin) from sea buckthorn leaves (SBL) combined with microwave-assisted extraction. The results showed that the extraction efficiencies of target flavonoids by DES were significantly superior to 70% ethanol. Aiming at obtaining the optimal procedure, the extraction conditions were statistically investigated. Under the optimal conditions in pilot-scale application, the total maximum extraction yields of five main flavonoids reached to 20.820 mg/g, which was 1.321–2.400 folds to those by the traditional extraction methods. Meanwhile, the following enrichment of targets compounds from DES extraction solution exhibited excellent recoveries in the range of 72.36–84.99% were achieved by macroporous resin AB-8. In addition, the enriched flavonoids by AB-8 resin exhibited better antioxidant activities as compared with those unenriched. The results indicated that the potential of the developed method as a promising safe and sustainable alternative for selectively extraction and separation of bioactive substances from plant materials.