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Mechanochemical ball milling can degrade high concentrations of persistent organic pollutants (POPs) in contaminated soil and even pure chemicals easily and efficiently. There are many relevant laboratory studies that discuss the selection of reagents and mechanism of pollutant degradation. However, there are few related studies on large-scale treatment and importance of collision energy in the system. The purpose of this study is to optimize the existing collision model and design horizontal ball mill to examine the influence of the internal structure on the collision energy. Studies have shown that not only the collision between balls, but also the collision between the balls and internal structure (balls and blades, balls and cylinder) accounts for a considerable proportion in the system. Besides, we found that the single impact energy determines whether the mechanochemical reaction occurs and the effective collision power determines the mechanochemical reaction rate during ball milling. Finally, we calculated that the effective collision power increases as the number of blades and blade-mill volume ratio, and different operating modes influence collision power significantly when the number of blades and blade-mill volume ratio exceed a certain threshold.

To degrade the chlorobenzenes from contaminated soil, herein, a novel peroxomonosulfate-ferrate-FeS (PFI) hybrid oxidation system has been proposed. Take the o-dichlorobenzene as a typical contaminant, results of bottle tests show that the PFI oxidation system performs well in removing the pollutant, achieving up to 93% of removal efficiency in less than 30 min. With the orthogonal experiments, the effects of different parameters on the degradation of o-dichlorobenzene have been systematically investigated. The degradation of the o-dichlorobenzene by the PFI oxidation system is found to be well matched by the quasi-first order kinetic model. Further mechanistic study shows that, in this system, a proper addition of FeS could not only facilitate the activation of persulfate to produce sulfate radicals to oxidize o-dichlorobenzene, but also enhance the conversion of ferrate(VI) to produce Fe(V) and Fe(IV) to attack o-dichlorobenzene. In this way, the peroxomonosulfate and ferrate could perform synergistically with the presence of FeS in degrading the o-dichlorobenzene. The o-dichlorobenzene is found to be degraded into o-chlorophenol, 2,3-dichlorophenol, 3,4-dichlorophenol and chlorohexane, and finally to be CO2, H2O, HCl. In addition, results also show that the application of PFI oxidation system could reduce heavy metals in the soil and improve the soil permeability.

Methanol and ethyl acetate are typical oxygen-containing volatile organic compounds which are widely used in industry, often leading to serious pollution. Herein, the adsorption–desorption hybrid p...

In this paper, the nanofluid (bionanofluid) was prepared by dispersing SiO2 nanoparticles (NPs) in water (biosurfactant-sophorolipid) solution. The nanofluid (bionanofluid) stability was measured t...

An organic–inorganic hydrophobic mesoporous silica has been successfully prepared by a co-condensation method with tetraethoxysilane (TEOS) and vinyltriethoxysilane (VTES) as mixed precursors under...

The interfacially active asphaltenes (IAA, 1.75 wt % of the total asphaltenes) from Indonesian asphalt rocks have been proven to be the major component in stabilizing the water-in-oil (W/O) emulsio...

The ionic liquids (ILs) are reported to perform well in enhancing the oil–solid separation (in pure state or in solution) and oil–water separation (in solution) processes through interfacial altera...

The vacuum swing adsorption (VSA) with silica gel (SG) is proved to be a promising method for the recovery of volatile organic compounds (VOCs). The adsorption mechanisms of o-xylene on silica gels with different pore size have been revealed through the mathematic modeling of adsorption isotherms. The analysis of adsorption kinetics indicates that SG with micropore shows a steep concentration front and a long breakthrough time due to the strong adsorption force field, negligible transfer resistance and compressive effect of favorable isotherm. However, the reversible capillary condensation and mass transfer resistance cause a dispersed front and a short breakthrough time for mesoporous SG. The fast desorption rate makes mesoporous SG more energy-efficient compared with SG with micropore. Accordingly, to further improve the front slope and utilization of mesoporous SG in the adsorption process, a small amount of SG with micropore was loaded in the end of the fixed bed. The breakthrough time of the piecewise loading bed increased by 55.8% at the same loading volume with single mesoporous SG. The energy consumption was observed to exhibit an obviously decrease from 1.819 kWh/m3 to 1.295 kWh/m3, which proved that the piecewise loading method could recover VOCs in a more energy-saving way.

In this work, the asphaltenes from natural Indonesia asphalt rocks were taken as raw materials for the preparation of micromesoporous enriched carbon material through pyrolysis (

Compared with abatement methods (regenerative thermal oxidizer, regenerative catalytic oxidizer, etc.), the adsorption–desorption combined method has been considered as a sustainable way to treat a...

Adsorption and desorption of acetone and ethyl acetate (two typical oxygenated VOCs) on silica gel have been systematically studied by vacuum swing adsorption (VSA) combined with temperature swing adsorption (TSA) process. It is found that the adsorption of both the oxygenated VOC compounds on silica gel could be well described by the Langmuir-Freundlich model. Although highly dependent on the operational parameters, the adsorption of both the oxygenated VOC compounds on silica gel is found to be controlled by external diffusion. When the two compounds are mixed, the adsorbed acetone is found to be partially replaced by the ethyl acetate when the adsorption approaches the saturation due to the stronger affinity of ethyl acetate to silica gel. It also suggests that there is a competitive adsorption between ethyl acetate and acetone. Further modeling demonstrates that the whole kinetic adsorption of binary oxygenated components could be divided into three steps: the free adsorption, the competitive adsorption and the equilibrium state. The final ratio of adsorbed acetone to ethyl acetate on silica gel is dependent on the adsorption bed height. The adsorbed oxygenated VOCs on silica gel are observed to be desorbed by vacuum pumping, which is also found to be significantly enhanced by increasing temperature (by ∼30 °C), achieving over 2.5 times of concentration increase in the desorbed gas stream.

Separation is widely involved in many fields, such as materials synthesis, gas purification or removal, water treatment, petroleum exploitation, soil remediation, food and medicine production, etc. Compared with the physical separation, the chemical separation has unique advantages when the functionalized process aids are added in systems. The CO2-responsive materials are considered as promising separating mediums due to their relatively green and easily recyclable properties, which realize the resource utilization of CO2. Up to date, the reported CO2-responsive materials are mainly referred to switchable-hydrophilicity solvents, switchable surfactants, switchable water additives, switchable ionic liquids and CO2-responsive polymers. These CO2-responsive materials can be switched by CO2 trigger at moderate conditions, showing switchable properties, such as hydrophilicity-hydrophobicity conversion, switching “on” or “off” surface-activity and switchable change in ionic strength. These switchable properties can be applied in separations, especially in oil-solid separation, oil-water separation, wastewater treatment and acid gas capture. In this review, the recent advances of CO2-responsive materials in separation fields above have been overviewed. Additionally, the present challenges and future engineering considerations have been touched to provide potential insights and theoretical fundamentals for developing CO2-responsive materials.

Quite different from the Canadian oil sands, the Indonesian asphalt rocks proved to be carbonate unconventional oil ores. The strong interactions between asphalt and minerals make water-based extraction work poorly in separating this kind of ore. Herein, a reactive extraction process has been proposed to separate asphalt and mineral solids from the ores through dissolving the mineral solids (i.e., carbonate minerals, metal oxides, etc.) by acids (formic acid). It is evidenced that most of the asphalt could be recovered and collected on the top of the solution by generated CO2. What's more, the unreacted formic acid could be recycled in this process. The dissolved metal ions could be efficiently recovered to obtain different by-products by chemical settling and crystallization. The amount of residual solids settled at the bottom of the reactor is very small. Further tests show that the reaction efficiency is highly dependent on the operational conditions, including temperature, stirring rate, acid dosage, concentration of acid, etc. It is also found that the reaction could allow minerals to be redistributed in different phases. Although some metal elements could be dissolved into solution, elements such as Fe, Al, S, Si, and Ti are observed to accumulate in asphalt froth. In addition to reacting with minerals, formic acid is also found to reduce asphalt viscosity. This reduction improves the reaction efficiency. Based on primary evaluations, the above findings suggest that the reactive extraction would be a potential process to exploit the Indonesian asphalt rocks (or other similar ores) due to its full recovery to all materials.

Ionic liquids have been considered for application in petroleum separation (especially in unconventional oil production) as interfacial functional materials at pure state or aqueous solution state. Herein, the interactions between bitumen and silica in ionic liquids (i.e., [Emim][BF4]) aqueous solution and pure ionic liquids have been investigated by dynamic contact angle, atomic force microscopy (AFM) and sum-frequency generation spectroscopy (SFG). Results show that the addition of ionic liquids in water enhances the equilibrium degree of bitumen recession from silica surface, while negligible change has been observed when the bitumen coated plate was put into the pure ionic liquids. The force measurements by AFM demonstrate that the bitumen-silica adhesion force in different systems are in the order of: DI water >1 mM [Emim][BF4] > pure [Emim][BF4]. Results of SFG detection show that the addition of [Emim][BF4] in the aqueous solution strengthens the orientation of water molecules on the silica surface, while making the water molecules more disordered on the bitumen surface. Consequently, a positively charged Helmholtz-like layer is formed by the [Emim]+ cations on negatively charged silica and bitumen surfaces.

Separation of heavy hydrocarbons from mineral surfaces is highly dependent on the oil composition and their host rock surface properties. Herein, the petroleum is divided into SARA fractions (saturates, aromatics, resins, asphaltenes) to investigate their desorption behaviors on different types of mineral surfaces (silica (SiO2), kaolinite (Al2Si2O5(OH)4) and calcium carbonate (CaCO3)). The Quartz Crystal Microbalance with Dissipation (QCM-D) tests show that the saturates and aromatics could desorb from the mineral surfaces spontaneously even in water, while no desorption was observed for the asphaltenes and resins. Although the above desorption could be enhanced by alkaline or surfactant solutions, great difference still appears to different oil fractions. Oil characterization shows that the heavy fractions (i.e., asphaltenes, resins) possess richer acid groups than those of light fractions, allowing the stronger affinity of heavy fractions to the mineral surfaces through polar and chemical interactions. Additionally, the heavy fractions dominate in determining the desorption properties of bitumen (the mixed fractions), and lead to more significant wettability alteration to the mineral surfaces. Furthermore, the oil fractions desorption is also found to be highly influenced by the mineral types. Compared with silica, kaolinite has stronger affinity to the heavy oil fractions, leading to smaller amount of desorption. While on the calcium carbonate surface, less than 11% of the coated oil fractions are observed to be desorbed. Surface characterizations summarize that, due to the difference in mineral composition, the affinity of minerals to oil components in aqueous solutions is given as: calcium carbonate (positively charged calcium ions) > kaolinite (containing –AlOH, –SiOH groups and heavy metal elements) > silica (–SiOH group). The above results reveal the differences among bitumen subfractions and mineral types, allowing potential insights to the development of enhanced oil recovery, such as aqueous-nonaqueous hybrid extraction process, solvent extraction, CO2-enhanced oil recovery, etc.

A switchable solvent with a diamine structure called N, N, N′, N′-tetraethyl-1, 3-propanediamine (TEPDA) has been synthesized through an alkylation reaction. This solvent can switch between its hydrophilic and hydrophobic states with the addition or removal of CO2, respectively. It is found that TEPDA can be applied as an organic solvent and can be ionized in water to form cations. With these properties, TEPDA was proven to perform well with water in separating heavy oil from a carbonate solid surface, resulting in over 10% additional oil recovery. A mechanistic study shows that in this aqueous/non-aqueous hybrid process, TEPDA acts mainly as a solvent in softening and dissolving heavy hydrocarbons (dissolution effect). Meanwhile, a small amount of ionized TEPDA in the aqueous phase acts as a surface-active material accumulating at the oil–water and water–solid interfaces (interfacial modification). Both of these effects work to enhance the detachment of oil from solid surfaces. Additionally, the quality of the recovered heavy oil and the cleanliness of the residual solids are both improved. After extraction, TEPDA can be efficiently recycled by CO2 and N2 bubbling without huge energy consumption compared to distillation. Further tests show that this water-assisted TEPDA process also performs well in detaching oil from other solid surfaces, such as metal and silica.

A novel amino acid ionic liquid-based deep eutectic solvent (TrpBF 4 /U) was synthesized using l -tryptophan, fluoroboric acid and urea. The melting point of TrpBF 4 /U was over 100 K lower than that of TrpBF 4 . It is found that the TrpBF 4 /U could form non-aqueous surfactant-free micro-emulsion through mixing with ethanol and toluene. The size of the micro-emulsion droplets was less than 7 nm and was dependent on the concentration of toluene. This newly prepared TrpBF 4 /U-based micro-emulsion was applied to extract the extra-heavy oil from carbonate asphalt rocks. Results showed that the oil recovery was enhanced by at least 11% compared with that without the TrpBF 4 /U micro-emulsions. The enhancement in the oil-solid separation was mainly ascribed to the interfacial alteration at the oil and mineral surfaces by the TrpBF 4 /U, including lowering the interfacial tension and increasing solid wettability. Assisted by the TrpBF 4 /U micro-emulsion, the quality of oil product (less solids entrained) and residual solids (less solvents attached) were also improved compared with traditional ionic liquids (i.e., [Emim]BF 4 ) at given conditions. It also demonstrated that the TrpBF 4 /U micro-emulsion could be recycled and reused at least 4 times without sacrificing its efficiency. The above findings suggested the potential applications of the amino acid ionic liquid-based deep eutectic solvent in oil-solid separations or other extractions.

Nanoparticles have been reported to be a promising candidate for the separation of heavy oil from its host rock's surface. These nanoparticles (NPs) are often dispersed and stabilized in the solution by some surfactants during the unconventional oil ores processing. Herein, the PEG600–KH560 (PK) has been grafted onto Fe3O4 NP surfaces, obtaining a kind of hydrophilically-modified recyclable nanoparticle. Results show that these NPs (averaged at around 16 nm for single sphere) could be well dispersed in water (no settling in 72 h), forming PK-Fe3O4 nanofluids (NFs) at 0.2 wt%. These PK-Fe3O4 NFs are found to be able to be quickly separated from the dispersions by an external magnetic field, and returning back to stable NFs when the magnetic field disappears and by shaking. The PK-Fe3O4 NFs have been further used for the enhancement of heavy oil recovery from oil sands. The floatation results show that the PK-Fe3O4 NFs could improve oil recovery by at least 12% compared with the traditional hot water extraction process (HWEP). After the extraction, up to 70% of the PK-Fe3O4 NPs could be directly recycled from the solution for further use. The rest of the NPs are left in the oil phase and attached on the residual solid surface. However, the efficiency of the PK-Fe3O4 NPs is found to be decreased when the recycling times exceed 5 due to the adsorption of oil components. A mechanistic study shows that the hydrophilic PK-Fe3O4 NPs could be adsorbed on the mineral surface, making the surface more hydrophilic. The hydrophilic surface and the agitation disturbance helps the liberation process of bitumen from the solid surfaces. On the other hand, when adding the PK-Fe3O4 NPs into the heavy oil–water system, the oil–water interface is found to be highly modified by the NPs, resulting in significant reduction of the oil–water interfacial tension. The above findings suggest that the PK-Fe3O4 NPs combined the surface-active role (surfactant) and the nano-size role (adsorption) together, which facilitates its role in oil sands separation.

Oil-water emulsions separation is a significant and intractable problem in many industrial processes, especially in petroleum industry. To deal with the demulsification of oil–water emulsions, a novel kind of amphiphilic magnetic demulsifier (M-ANP) has been designed and successfully synthesized by grafting aliphatic alcohol nonionic propylene oxide-ethylene oxide block polyether (ANP) (~22.3 mg/g) onto the surface of epoxy-functionalized magnetite (Fe3O4) nanoparticles (~9.1 nm). The physicochemical and interfacial properties of M-ANP have been characterized and analyzed. The bottle tests show that the M-ANP performs well in fast (less than 5 min) and relatively complete demulsifying (up to 95.5%) both water-in-oil emulsions (water-in-crude oil, water-in-bitumen) and oil-in-water emulsions (diesel-in-water, crude oil-in-water, etc.) under room temperature. It also works well in breaking the stable water-in-asphaltene emulsions, achieving the demulsification efficiency of 90.0% within 2 min without heating (at 2000 ppm of M-ANP). Mechanistic study shows that the ANP and magnetic nanoparticles work synergistically in emulsions separation. The hydrophilic polyethylene oxide segments in the ANP would form hydrogen bonds with water, facilitating the interfacial adsorption of M-ANP. Furthermore, the multi-functional characteristics of magnetic nanoparticles (nano size, magnetic response and high density) promote the transfer of nanoparticles in dispersed phase and enhance the gravity settling and magnetic separation process of coalesced droplets. This kind of nanoparticle demulsifier would serve for promising applications in a variety of industrial and environmental processes at an energy-saving way.

A facile and feasible interfacial self-assembly approach was developed to synthesize flower-like Cu 2 O/Bi 2 O 2 CO 3 micro-composites. Degradation of methylene blue (MB) was used to evaluate the photocatalytic activity of composite under visible light. When compared to Bi 2 O 2 CO 3 , the flower-like Cu 2 O/Bi 2 O 2 CO 3 micro-composites show higher photocatalytic activity. Additionally, our results indicate that the photocatalytic activity of Cu 2 O/Bi 2 O 2 CO 3 composites is dependent on Cu 2 O loading. The highest photocatalytic performance of Cu 2 O/Bi 2 O 2 CO 3 micro-composites is 94% after irradiation for 20 min, which is 3–5 times that of pure Cu 2 O (calculated based on the equivalent Cu 2 O content in Cu 2 O/Bi 2 O 2 CO 3 ) and pure Bi 2 O 2 CO 3 respectively. Photocatalytic mechanism for the degradation of MB over Cu 2 O/Bi 2 O 2 CO 3 was proposed based on the above. Our results provide an invaluable methodology for designing high visible-responsive photocatalysts based on Cu 2 O/bismuth and related functional materials, which is promising for semiconductor composites and new energy applications.

Lutein is widely used as diet supplement for prevention of age-related macular degeneration. However, the application and efficacy of lutein in food and nutritional products has been hampered due to its poor solubility and low oral bioavailability. This study aimed to develop and evaluate the formulation of oral fast-dissolving film (OFDF) containing lutein nanocrystals for enhanced bioavailability and compliance. Lutein nanocrystals were prepared by anti-solvent precipitation method and then encapsulated into the films by solvent casting method. The formulation of OFDF was optimized by Box-Behnken Design (BBD) as follows: HPMC 2.05% (w/v), PEG 400 1.03% (w/v), Cremophor EL 0.43% (w/v). The obtained films exhibited uniform thickness of 35.64 ± 1.64 μm and drug content of 0.230 ± 0.003 mg/cm2 and disintegrated rapidly in 29 ± 8 s. The nanocrystal-loaded films with reconstituted particle size of 377.9 nm showed better folding endurance and faster release rate in vitro than the conventional OFDFs with raw lutein. The microscope images, thermograms, and diffractograms indicated that lutein nanocrystals were highly dispersed into the films. After administrated to SD rats, t max was decreased from 3 h for oral solution formulation to less than 0.8 h for OFDF formulations, and C max increased from 150 ng/mL for solution to 350 ng/mL for conventional OFDF or 830 ng/mL for nanocrystal OFDF. The AUC 0-24h of conventional or nanocrystal OFDF was 1.37 or 2.08-fold higher than that of the oral solution, respectively. These results suggested that drug nanocrystal-loaded OFDF can be applied as a promising approach for enhanced bioavailability of poor soluble drugs like lutein.

The removal and recovery of o-xylene (a typical volatile organic compounds, VOCs) by silica gel has been systematically investigated by vacuum swing adsorption (VSA) process. Laboratory scale measurements show that the adsorption of o-xylene on silica gels could be significantly enhanced by increasing the height to diameter ratio (H/D) of adsorption bed, the inlet flowrate and o-xylene initial concentration. However, reducing the H/D and desorption pressure or increasing the amount of purging gas are observed to be favorable for the desorption of o-xylene from the silica gels. The optimized operational conditions are determined at 5:1 for H/D, 5 kPa (absolute) of desorption pressure and 0.45 L/min of purge gas flowrate. According to further kinetic fitting and analysis, it is found that the adsorption of o-xylene on this silica gel is film-diffusion control, which could be enhanced by increasing gas flowrate or initial o-xylene concentration. In addition, reducing the particle size of the silica gel is also found to increase the saturation of adsorbed o-xylene in silica gels. A scaled-up integrated VSA setup was applied to confirm the above results, leading to a complete o-xylene removal from the gas (100% removed) with 87% of o-xylene recovered directly as liquid. Based on a rough economic calculation, the VSA shows greater merits than those of traditional thermal treatment and absorption methods, due to its recovered VOCs as products. Additional tests by other aromatic VOCs further approved the feasibility of the VSA using silica gels. These findings indicate that the VSA with air cooling at ambient temperature would be a promising and ‘green’ technology for treating high boiling VOCs.

An energy-saving set-up of pressure swing adsorption has been designed and applied to remove the high concentrations of toluene vapor (∼12,000 ppm) by silica gel at ambient temperature. It is evident that the adsorption of toluene vapor on silica gel matches the Langmuir–Freundlich model during the whole vapor concentration (up to 3.5 kPa), which is different from that on traditional activated carbon (AC). Results also show that it is much easier and faster for silica gel to adsorb toluene than that of AC. Mechanistic study by microporous characterizations and thermodynamic analysis shows a higher isosteric heat of toluene adsorbed on silica gel (∼55 kJ/mol) compared with that on AC (∼43 kJ/mol) due to a much more significant multilayer adsorption on AC. The vacuum desorption tests show that the desorption capacity of toluene vapor from the silica gel is much higher (61.6% desorbed) than that from AC (46.22% desorbed) at ambient conditions. In addition, an obvious accumulation of toluene has been observed on AC after a five-cycle of dynamic adsorption-desorption tests. Long-time run tests demonstrate that over 75% of the adsorbed toluene could be recovered from the silica gel. Considering the long-time run in future application, the silica gel would be a better candidate for the removal and recovery of high concentrations of toluene vapor from gas stream using the normal adsorption and vacuum desorption combined process at ambient temperature.

Separation of heavy hydrocarbons from mineral surfaces is the key step for unconventional oil production and remediation of oil-contaminated soils. The presence of asphaltene and the coexistence of mineral rocks are considered as the most challenge during the above separation processes. Herein, the liberation of asphaltenes (and/or heavy oil) on the muscovite [KAl2(Si3Al)O10(OH)2)] surface has been systematically investigated through instrumental characterization and molecular dynamics (MD) simulation. It is observed that, quite different from that on the silica surface, asphaltenes can flake off from the muscovite surface as a result of the weaker adhesion force between asphaltenes and the muscovite surface. This liberation pattern was also found to be influenced by the addition of other oil fractions. The micro force measurements by atomic force microscopy show that the adhesion force between asphaltenes and muscovite is weaker than that between asphaltenes and silica in both air and water. Assisted by ...

Novel core–shell structured ellipsoid-like BiVO4@g-C3N4 composites, with different amounts of g-C3N4, have been successfully prepared by a simple hydrothermal-chemisorption method. Their performance as photocatalysts was systematically evaluated during RhB degradation under visible light irradiation. The composite with 7 wt% g-C3N4 was found to be 7 times more efficient as a photocatalyst than pristine BiVO4. Its core–shell structure and activity were also found to be highly stable after it was used for 5 times in RhB degradation. The new composites were examined by various characterization techniques. The core–shell structure enhanced the contact area between the BiVO4 core and g-C3N4 nano-sheet shell, which provided more active sites and strengthened the chemical band interaction. The thin g-C3N4 nano-sheets reduced the charge carrier transfer distance, which further suppressed the recombination of the photo-induced electron–hole pairs and therefore enhanced the photocatalytic activity of the composites. A reaction mechanism of the photocatalytic RhB degradation was proposed and discussed in detail.

The adsorption-desorption combined process has been considered as a promising method for the industrial VOCs (volatile organic compounds) treatment. Herein, a carbon-silicon composite adsorbent material has been prepared for the removal of VOCs at lower potential flammable risk. The preparation involves two main steps: Extrusion forming and thermal treatment. The carboxymethyl cellulose and silicate were adopted as binder and fire retardant respectively. The molding and inflaming retarding mechanisms were proposed and discussed. Results show that the newly prepared doping combined material is micro-mesoporous with a specific surface area of 729 m2/g. The maximum adsorption capacity of carbon-silicon doping combined material to p-xylene is observed to be 292 mg/g. The adsorption is found to be favorable, which is well described by the Yoon-Nelson model and Freundlich isotherm. The combined material is also found to possess reversible adsorption to p-xylene, without sacrificing (&lt, 2%) too much adsorption capacity after five adsorption-desorption cycles. The composite materials have an increased ignition temperature of at least 40 &deg, C compared with raw carbon material. These findings suggest that the obtained composite material possesses good adsorption capacity and flame-retardant properties.

In this study, a series of choline-based amino acid ionic liquids have been synthesized in an economic method and are used to assist solvents with extracting asphalt from carbonate rocks. All of the ionic liquids perform well in extracting asphalt, especially choline histidine, by which the single-step recovery of asphalt is up to 91%. Furthermore, oil product with higher quality (fewer solids entrained) is also obtained. Molecular dynamics simulation and thermodynamic equilibrium method are applied to investigate the role of amino acid ionic liquids via interaction energy calculation and surface free energy calculations. The simulation results suggest that the ionic liquid phase is beneficial for the transfer of oil fraction from the carbonate surface to the organic solvent phase. Moreover, the results of simulated calculation show that the introduction of a functional group with conjugated structures into ionic liquid, such as an imidazole ring and a benzene ring, is beneficial for enhancing oil recovery, which are in accordance with the results of experimental tests.

Solvent loss in the residual solids has been considered as a major challenge during the solvent extraction processes of unconventional oil ores (oil sands, asphalt rocks, etc.). Herein, we proposed a gas bubbling method to remove and recover the residual solvents from the extracted gangue for the purpose of solvent reuse and environment remediation. Results show that under the optimal conditions, more than 99.6 wt% of solvent (toluene) in the gangue could be removed and 92.3 wt% of solvent could be directly recovered with the condensation-compression combination process. The effects of water chemistry, gas types (CO2 or N2), and mineral types (calcite and quartz) on the removal efficiency have been investigated. The mechanism of solvent removal from residual solids by the gas bubbling process is deduced to contain several sub-processes, including bubble-oil droplet/solid particle colliding and coalescing; solvent droplet spreading on the bubble surface and evaporating into the bubble; droplets coalescing and solvent evaporating to the gas phase. Meanwhile, the kinetic model of the bubbling process is demonstrated, which matches the first order kinetic model. This process would provide insights for other similar situation about oil or solvent removal and recovery from solids.

Quite different from the Canadian oil sands in oil content/composition, mineral composition, and particle size distribution, the carbonate Indonesian asphalt rocks (oil-wetted) are proven to be poorly extracted by the commercial hot-water-based extraction (7.8% bitumen recovery at 50 °C and pH 9.0). Great enhancement was obtained using multi-staged solvent extraction with four typical solvents (i.e., toluene, n-heptane, n-hexane, and cyclohexane), resulting in a cumulative bitumen recovery up to 98% at ambient conditions. After the extraction, a systematical particle sedimentation test has been conducted in the non-aqueous phase. It is found that there are oil-phase and consolidated zone with only one clear solid–liquid interface appearing in the toluene and cyclohexane solutions with high bitumen during the carbonate particle sedimentation. However, an extra “settling zone” appeared between the oil-phase and consolidated zone in n-heptane and n-hexane solutions, resulting in the appearance of two solid–l...

Lung-targeting sophoridine-loaded poly(lactide-co-glycolide) (PLGA) microspheres were constructed by a simple oil-in-oil emulsion-solvent evaporation method. The obtained microspheres were systematically studied on their morphology, size distribution, drug loading, encapsulation efficiency, in vitro release profile, and biodistribution in rats. The drug-loaded microparticles showed as tiny spheres under SEM and had an average size of 17 μm with 90% of the microspheres ranging from 12 to 24 μm. The drug loading and encapsulation efficiency were 65% and 6.5%, respectively. The in vitro drug release behavior of microspheres exhibited an initial burst of 16.6% at 4 h and a sustained-release period of 14 days. Drug concentration in lung tissue of rats was 220.10 μg/g for microspheres and 6.77 μg/g for solution after intraveneous injection for 30 min, respectively. And the microsphere formulation showed a significantly higher drug level in lung tissue than in other major organs and blood samples for 12 days. These results demonstrated that the obtained PLGA microspheres could potentially improve the treatment efficacy of sophoridine against lung cancer.

Biohydrogen generation using anaerobic sludge from a sewage treatment plant is a promising strategy for converting waste into renewable energy. The porous foam SiC ceramic structured packing was used as a support in the up-flow anaerobic sludge blanket (UASB) reactor to enhance the biohydrogen yield. Using glucose as the major carbon source, the SiC-UASB reactor was continuously operated under the organic loading rates (OLR) between 30 and 90 gglucose/L · d at a hydraulic retention time (HRT) of 4 h. The maximum hydrogen production rate (5.24 L/L · d) and hydrogen content (50%) were obtained at 60 gglucose/L · d OLR. It demonstrated that the reaction of fermentation was predominated by the butyric acid pathway. The employment of SiC packings resulted in quick startup (∼5 days) and high efficiency of hydrogen production. The buffering capacity and the cell culture immobilization ability of the UASB reactor were obviously improved by the application of SiC packings, which increased the feasibility of scale-up of the continuous biohydrogen production system. This article is protected by copyright. All rights reserved

Selection of solvents and process aids (i.e., ionic liquids (ILs)) is considered to be one of the key steps during solvent extraction for heavy hydrocarbon recovery from unconventional oil ores. In this study, the COSMOtherm software was applied to screen highly efficient solvents and ionic liquid systems based on oil fraction solubility and surface free energy calculations. It is found that the dispersion force parameter (δd) of solvents plays the dominant role in dissolving oil fractions compared with the roles of the polar force parameter (δp) and hydrogen bonding force parameter (δh). The simulation results also show that the surface free energy of oil fractions (SARA fractions) at the organic solvent-IL interface is significantly lower than that found at the IL-SARA fraction interface, which is favorable for unconventional oil dissolution in solvents. In addition, further interactive energy calculation shows that the interaction between IL and the silica surface is stronger than that between oil frac...

Ethyl cellulose (EC) and EO/PO polymers are known as efficient demulsifiers for breaking oil–water emulsions, which are applied in this study as process aids to enhancing unconventional oil liberation from host rock surfaces. Their applicability in such a role was assessed by studying dynamic contact angle and liberation of bitumen from model solid surfaces. The addition of demulsifiers (EC and/or EO/PO blocked co-polymer, up to 300 ppm) into the solvent-diluted bitumen was found to significantly improve both bitumen liberation rate and ultimate degree of bitumen liberation (DBL) from glass surfaces. This finding suggests the potential combination of oil liberation and demulsification to develop more efficient process for recovering unconventional oils.

A binary solvent of ethyl acetate and n-heptane was made and applied together with ionic liquids (ILs, 1-ethyl-3-methyl imidazolium tetrafluoroborate ([Emim]BF4)) to extract bitumen from oil sands at ambient conditions. Results of bottle tests show that the bitumen recovery is highly dependent on the volume ratio of ethyl acetate to n-heptane. The maximum recovery was obtained at the ethyl acetate-to-n-heptane ratio of 3:6. With external addition of ILs, an additional improvement of ∼10 % of bitumen recovery was observed (from 83 to 93 % at the ethyl acetate-to-n-heptane ratio of 3:6). Based on the intensive investigation of key operational parameters (i.e. ILs-to-solvent ratio, agitation time, and conditioning time), a set of recommended extraction conditions were proposed to maximize the bitumen recovery. Further fractionation of the extracted bitumen together with FTIR and SEM detection on the residual solids indicated that ILs addition could increase the dissolution of bitumen fractions into solvents, while reducing the entrapment of fine particles in the solvents. The improvement of bitumen recovery by ILs addition was attributed to the enhancement of the liberation of bitumen components from mineral solids surfaces during oil sands solvent extraction. However, the asphaltenes were observed to be rejected during processing due to their accumulation at the oil-ILs interface as a film.

The triethylene glycol (TEG) was used to treat the off-gas stream containing 16 volatile organic compounds (VOCs) with high concentration (up to 15000 ppm) by experimental solvent absorption and ASPEN Plus computational simulation, respectively. This solvent absorption technology (SAT) not only purifies the off-gas but also recovers the VOCs. The effects of some typical operational parameters, including temperature, pressure, liquid loading rate, ratio of absorption liquid to gas flow rates, and absorption column height, on the absorption efficiency have been systematically investigated. Simulation results show that the optimal operational conditions are determined as 30 °C, 0.5 MPa (absolute), recycling TEG (with a purity of 99.9%) to a gas ratio of 4:1 by weight, and 8 theoretical stages. In addition, two stages of thermal coupling are applied minimizing the energy consumption of the off-gas absorption process, leading to a reduction of 89.77% in energy consumption. Laboratory experiments and field test...

The persistence of polycyclic aromatic hydrocarbons (PAHs) in contaminated soils is largely controlled by their molecular fate in soil pores. The adsorption and diffusion of 16 PAHs mixture in silica nanopore with diameter of 2.0, 2.5, 3.0 and 3.5 nm, respectively, were characterized by adsorption energy, mean square displacement, free surface area and free volume fraction using molecular dynamic (MD) simulation. Results suggested that PAHs adsorption in silica nanopores was associated with diffusion process while competitive sorption was not the dominant mechanism in context of this study. The partial least squares (PLS) regression and machine learning (ML) methods (i.e. support vector regression, M5 decision tree and multilayer perceptrons) were used to correlate the adsorption energy with the pore diameter and PAH properties (number of carbon atoms, aromatic ring number, boiling point, molecular weight, octanol-water partition coefficient, octanol-organic carbon partition coefficient, solvent accessible area, solvent accessible volume and polarization). Results indicated that the PAH adsorption could not be predicted by linear regression as the R(2)Y and Q(2)Y coefficients of PLS analysis was 0.375 and 0.199, respectively. The nonlinearity was well recognized by ML with correlation coefficient up to 0.9. Overall, the combination of MD simulation and ML approaches can assist in interpreting the sequestration of organic contaminants in the soil nanopores.

Hydrophobic modification of Bletilla striata polysaccharide (BSP) was performed by grafting fatty acids to BSP backbone and then characterized on their physicochemical properties. All neutral derivatives were able to self-assemble into spherical particles within the size range of 250-400 nm, their size and critical micelle concentration decreased with increasing hydrophobicity and substitution degree of the fatty acids. Also, the BSP-stearic acid conjugates showed a preferable performance on hemolysis test and cytotoxicity analysis on HepG2 cells, which suggested their potential application as a drug delivery vector.

A novel aliphatic alcohol nonionic polyether (MJTJU-2) has been successfully synthesized by esterification and polymerization. It is found that this new polyether is efficient in fast demulsifying the water-in-oil emulsions, including water-in-diesel emulsion, water-in-crude oil emulsion, water-in-asphalt oil emulsion and water-in-asphaltenes solution emulsion, etc. Take the most stable emulsion (interfacially active asphaltene (IAA)-stabilized emulsions) as an example, almost complete dehydration (>97%) to the emulsions could be achieved in less than 15 min at 60 °C using 400 ppm of MJTJU-2. This demulsification of IAA-stabilized emulsions is much faster than other reported work by traditional or commercial demulsifiers (up to several hours). To comprehensively understand how the MJTJU-2 influence the demulsification efficiency, the operational parameters (e.g., demulsifier dosage, temperature, settling time) have been systematically investigated and optimized. The excellent performance of MJTJU-2 in demulsifying the oil-water emulsions is considered mainly to be ascribed to the rich hydrophilic groups (i.e., hydroxyl, ester groups, carboxyl groups, ether groups) in the demulsifier molecules. These oxygen-containing groups help to break the IAA-formed film at the oil-water interface, which would be replaced by newly formed bonding. These findings suggest that the MJTJU-2 demulsifier would be potential engineering efficient process aids for the demulsification of water-in-oil emulsions.

Noninvasive prenatal detection of monogenic diseases based on cell‐free DNA is hampered by challenges in obtaining a sufficient fraction and adequate quality of fetal DNA. Analyzing rare trophoblastic cells from Papanicolaou smears carrying the entire fetal genome provides an alternative method for noninvasive detection of monogenic diseases. However, intracellular labeling for identification of target cells can affect the quality of DNA in varying degrees. Here, a new approach is developed for nondestructive identification of rare fetal cells from abundant maternal cells based on endoplasmic reticulum staining and linear discriminant analysis (ER‐LDA). Compared with traditional methods, ER‐LDA has little effect on cell quality, allowing trophoblastic cells to be analyzed on the single‐cell level. Using ER‐LDA, high‐purity of trophoblastic cells can be identified and isolated at single cell resolution from 60 pregnancies between 4 and 38 weeks of gestation. Pathogenic variants, including –SEA/ deletion mutation and point mutations, in 11 fetuses at risk for α‐ or β‐thalassemia can be accurately detected by this test. The detection platform can also be extended to analyze the mutational profiles of other monogenic diseases. This simple, low‐cost, and noninvasive test can provide valuable fetal cells for fetal genotyping and holds promise for prenatal detection of monogenic diseases., An endoplasmic reticulum staining and linear discriminant analysis single‐cell test for detecting rare trophoblastic cells in Pap samples from pregnancies whose fetuses are at risk for monogenic disorders is presented. The antibody‐free, simple, low‐cost assay enables genomic analysis of fetal trophoblastic cells with high performance, which can serve as a promising tool for prenatal detection of monogenic diseases.

Ionic liquids (ILs) have been reported to be good process aids for enhanced bitumen recovery from oil sands. However, after the extraction, some ionic liquids are left in the residual solids or solutions. Herein, a washing&ndash, ion exchange combined method has been designed for the removal of two imidazolium-based ILs, ([Bmim][BF4] and [Emim][BF4]), from residual sands after ILs-enhanced solvent extraction of oil sands. This process was conducted as two steps: water washing of the residual solids to remove ILs into aqueous solution, adsorption and desorption of ILs from the solution by the sulfonic acid cation-exchange resin (Amberlite IR 120Na). Surface characterization showed that the hydrophilic ionic liquids could be completely removed from the solid surfaces by 3 times of water washing. The ionic liquids solution was treated by the ion-exchange resin. Results showed that more than 95% of [Bmim][BF4] and 90% of [Emim][BF4] could be adsorbed by the resins at 20 &deg, C with contact time of 30 min. The effects of some typical coexisted chemicals and minerals, such as salinity, kaolinite (Al4[Si4O10](OH)8), and silica (SiO2), in the solution on the adsorption of ionic liquids have also been investigated. Results showed that both kaolinite and SiO2 exerted a slight effect on the uptake of [Bmim][BF4]. However, it was observed that increasing the ionic strength of the solution by adding salts would deteriorate the adsorption of [Bmim]+ on the resin. The adsorption behaviors of two ILs fit well with the Sips model, suggesting the heterogeneous adsorption of ionic liquids onto resin. The adsorption of ionic liquids onto Amberlite IR 120Na resin was found to be pseudo-second-order adsorption. The regeneration tests showed stable performance of ion-exchange resins over three adsorption&ndash, desorption cycles.

With low melting point, extremely low vapor pressure and non-flammability, ionic liquids have been attracting much attention from academic and industrial fields. Great efforts have been made to facilitate their applications in catalytic processes, extraction, desulfurization, gas separation, hydrogenation, electronic manufacturing, etc. To reduce the cost and environmental effects, different technologies have been proposed to recover the ionic liquids from different solutions after their application. This review is mainly focused on the recent advances of the recovery and purification of ionic liquids from solutions. Several methods for recovery of ionic liquids including distillation, extraction, adsorption, membrane separation, aqueous two-phase extraction, crystallization and external force field separation, are introduced and discussed systematically. Some industrial applications of ionic liquid recovery and purification methods are selected for discussion. Additionally, considerations on the combined design of different methods and process optimization have also been touched on to provide potential insights for future development of ionic liquid recovery and purification.

Mechanochemical destruction has been proposed as a promising, non-combustion technology for the disposal of toxic, halogenated, organic pollutants. In the study presented, additives including Fe, Zn, Fe-Zn bimetal, CaO and Fe2O3 were tested for their effectiveness to remove DDTs by MC. The results showed that Fe-Zn bimetal was the most efficient additive, with 98% of DDTs removed after 4 h. The Fe-Zn mass ratio was optimized to avoid possible spontaneous combustion of the ground sample during subsample collection. Inorganic water-soluble chloride in the ground sample increased by 91% after 4 h of grinding, which indicated dechlorination during destruction of DDTs. In addition, relationships were established between the rate constant and the rotation speed or the charge ratio. Discrete Element Method (DEM) modeling was used to simulate the motion of the grinding ball and calculate both total impact energy and normal impact energy. The latter expressed a stronger, linear correlation with the rate constant. Therefore, normal impact energy is proposed to be the main driving force in the MC destruction of DDTs.

This study aimed to investigate the performance of the eutectic mixture of menthol and camphor (1:1, w/w) in nanoemulsion formulation for enhanced transdermal penetration of water-insoluble glabridin. Glabridin solubility in different media was determined by a shaking bottle method. The pseudoternary phase diagrams of the oil phase (drug-loaded eutectic mixture or IPM), the surfactant (Tween 80:glycerol = 2:1, w/w), and water were constructed using the aqueous titration method. The obtained glabridin nanoemulsions were characterized and compared on their particle sizes, in vitro and in vivo penetration performance on rat skin, and storage stability. The nanoemulsion formulation was optimized as 0.25% glabridin, 5% oil phase, 10% Tween 80, 5% glycerol, and 79.75% water. The obtained nanoemulsions showed a mean droplet size of nearly 100 nm for different oil phases. And the stability of both formulations was similar after storage for 3 months. In vitro skin permeation study showed that the nanoemulsion formulation with eutectic mixture exhibited higher skin permeability (28.26 μg/cm2) than that with IPM (9.94 μg/cm2) or the drug solution formulation (3.82 μg/cm2), which was further confirmed by in vivo skin permeation tests on the rat skin and human skin. The eutectic mixture is a preferable solvent for glabridin, and its nanoemulsion can be used as an excellent nanocarrier for enhanced transdermal delivery of glabridin.

Bitumen liberation is known to be an essential step for bitumen recovery from sand grains using the current warm/hot-water-based extraction process. This study aims at understanding the role of naphtha or toluene addition in enhancing bitumen liberation. Results from an in situ bitumen liberation visualization measurement indicate that soaking two oil sands ores by solvents at 10–30 wt % of the bitumen could significantly enhance not only the ultimate degree of bitumen liberation (UDBL) but also the rate of bitumen liberation (RBL) in the process water at ambient conditions. Although ore-type- and solvent-type-dependent, both the UDBL and RBL would increase sharply at 10–20 wt % solvent dosage. A further increase in solvent dosage showed a diminished increase in the UDBL. To understand the observed improvement, viscosities of bitumen directly extracted from the ores and its mixture with solvents were measured, as well as diluted bitumen–water interfacial tensions. Results showed that adding solvent into t...

C27H33Cl3N4O4, monoclinic, P21/n (no. 14), a = 7.1343(4) Å, b = 22.4930(10) Å, c = 9.7835(4) Å, β = 106.876(5), V = 1502.37(13) Å3, Z = 2, R gt(F) = 0.0605, wR ref(F 2) = 0.1517, T = 179.99(10) K

The heat released during the industrial gas adsorption (e.g., volatile organic compounds (VOCs)) on adsorbents (e.g., activated carbon) would lead to the risks of fire and explosion in the adsorption column. Herein, a novel highly-porous Vinylbenzyl chloride-Divinylbenzene (VBC-DVB) polymeric adsorbent was synthesized with embedded microcapsules (Hypercrosslinked VBC-DVB Beads (HVPM)). These microcapsules have a polydivinylbenzene-phase change materials (DVB-PCMs) core-shell structure. Paraffin wax was used as PCM filling in the spherical capsule. This microcapsules-embedded polymeric adsorbent HVPM (&Phi, 1.5&ndash, 2.0 mm) is found to possess a high specific surface area (~665 m&sup2, /g) and micropore-dominant structure. It also has heat storage capability indicated by DSC (Differential Scanning Calorimetry) analysis (11.1 J/g heat of fusion between 35.0 and 48.2 &deg, C) for the encapsulated paraffin wax. The lab adsorption tests proved the capabilities of HVPM in adsorbing VOCs (toluene, 0.21 g/g) and controlling the temperature inside the adsorption column during the dynamic adsorption process, in which the temperature rise was lowered by 62.5%, relatively.

The aim of the present study was to prepare and evaluate microparticle formulation encapsulated with glycyrrhetinic acid (GA) based on bovine serum albumin (BSA). The drug-loaded nanoparticles were firstly formed by a simple desolvation method, and were further assembled into microparticles using zinc chloride and glutaraldehyde as crosslinkers. The obtained microparticles contained approximately 30% (w/w) drug and showed as spherical particles with a size of about 2 μm. Differential scanning calorimetry (DSC) and X-ray powder diffraction (XRPD) analysis indicated that GA lost its crystallinity during the nano/microencapsulation process. In vitro dissolution study demonstrated a typical sustained-release pattern for 24 h with a burst of 28.1% at the first 30 min, which fitted well by Higuchi model. After intravenous administration into mice, the microparticle formulation remained a higher drug level than the solution formulation in blood and liver for more than 18 h. These results suggested the potential benefit of using the prepared albumin microparticles as a promising vector for enhanced liver delivery of poorly water-soluble drug.

The purpose of this study was to prepare solid nanocrystals of glycyrrhetinic acid (GA) for improved oral bioavailability. The anti-solvent precipitation-ultrasonication method followed by freeze-drying was adopted for the preparation of GA nanocrystals. The physicochemical properties, drug dissolution and pharmacokinetic of the obtained nanocrystals were investigated. GA nanocrystals showed a mean particle size of 220 nm and shaped like short rods. The analysis results from differential scanning calorimetry and X-ray powder diffraction indicated that GA remained in crystalline state despite a huge size reduction. The equilibrium solubility and dissolution rate of GA nanocrystal were significantly improved in comparison with those of the coarse GA or the physical mixture. The bioavailability of GA nanocrystals in rats was 4.3-fold higher than that of the coarse GA after oral administration. With its rapid dissolution and absorption performance, the solid nanocrystal might be a more preferable formulation for oral administration of poorly soluble GA.

In this study, SHT (switchable-hydrophilicity triethylamine, [Et3NH]&middot, [HCO3]) has been synthesized and instrumentally characterized by Fourier transform&ndash, infrared spectroscopy (FTIR) and 13C nuclear magnetic resonance (NMR). The operational synthesis conditions of SHT were optimized and determined at 25 &deg, C, Et3N/H2O volume ratio of 1:2 and CO2 injection rate at 300 mL/min. When it was used to extract heavy oil from unconventional oil ore, it was found that it could break maltenes-in-water emulsions. When asphaltenes were present in the oil phase, it was observed that SHT could cooperate with asphaltenes. These results indicated that SHT works with asphaltenes, leading to synergistic effects in stabilizing oil&ndash, water (o/w) emulsions.

A new, simple one-step approach has been developed to synthesize lignin and lignin amine coated Fe3O4 nanoparticles. These nanoparticles (lignin magnetic nanoparticles (LMNPs) and lignin amine magnetic nanoparticles (LAMNPs)) are found to possess not only magnetic response but also pH-dependent adsorption behavior. Results show that the combination of lignin with nanoparticles increased the adsorption capacities 2–5 times higher than other traditional single lignin based adsorbents (211.42 mg/g for methylene blue (MB) by LMNPs and 176.49 mg/g for acid scarlet GR (AS-GR) by LAMNPs). Meanwhile, by simply adjusting the pH, the dye-loaded adsorbents can be regenerated to recycle both adsorbents and dyes with a desorption efficiency up to 90%. Mechanistic study shows that dye structure and surface charges of adsorbents play the most important part in adsorption where dyes interact with the adsorbent surface via π–π stacking and electrostatic attraction interactions. The efficient fabrication method, eco-friendly reactant, quick magnetic separation, high adsorption and desorption efficiency suggest this novel type of nano-adsorbents to be promising materials for efficient dye pollutant removal and recovery.