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Abstract: In this study, ibuprofen, a common non-steroidal anti-inflammatory drug with low water-solubility was used as a model drug for its nanosizing via a PGSS™ (particles from gas-saturated solutions)-based method. A modified PGSS™ process was employed to prepare PEG6000-ibuprofen composite particles after investigating the solid–liquid–gas phase equilibrium behavior of the PEG6000–ibuprofen–CO2 system. The composite powder was then dispersed into water to remove PEG6000 and obtain ibuprofen nanoparticles. The effects of pressure, temperature, and mass fraction of ibuprofen in the composite on the ibuprofen particle size and particle morphology were investigated. Results showed that spherical ibuprofen nanoparticles with diameter of 20–500nm were prepared at different conditions. Additionally, the dissolution rates of different ibuprofen particles were studied, indicating much faster dissolution of the obtained ibuprofen nanoparticles compared with the raw material and those from the direct physical mixing approach in the phosphate buffer solution (pH=7.2±0.02). This can be attributed to the reduced size and the reduced crystallinity of the ibuprofen particles from the modified PGSS™-based process. [Copyright &y& Elsevier]

Graphical abstract Highlights • CO 2 -expanded gelation approach was proposed for preparing bimodal porous materials. • CO 2 -expansion induced much short time for gelation. • CTAB template contributed to the surface area and CO 2 -expansion to the pore volume. • Bimodal silica-PW showed good selectivity and short time for 1,8-cineole from α-terpineol. • Bimodal Ni/SiO 2 exhibited excellent performance for phenol hydrogenation to cyclohexanol. Abstract In this work, a facile route was designed to fabricate bimodal porous silica with high surface area and pore volume via a CO 2 -expanded gelation with assistance of CTAB. Parameters such as the amount of CTAB, pressure of CO 2 and agitation time were investigated and optimized. Results showed bimodal silica contained small pore size (around 2 nm) from CTAB templating and large pore size (> 4 nm) from CO 2 -expanded gelation could be easily adjusted by the synthesis conditions. A typical sample with surface area of 1133 m2/g and pore volume of 1.24 mL/g was applied as a catalyst support for phosphotungstic acid, revealing much faster catalysis rate and relatively high selectivity for 1, 8-cineole from α-terpineol than the commercial MCM-41. The approach was also successfully extended to the preparation of bimodal NiO/silica composite, and the reduced Ni/silica showed higher catalysis performance than the unimodal sample for phenol hydrogenation to cyclohexanol. [ABSTRACT FROM AUTHOR]

A solute-saturated supercritical fluid loading (SSFL) process was proposed to load 2-phenylethyl alcohol (PEA) in silica and activated carbon (AC). The adsorption and loading amounts of PEA in carries were investigated at different temperatures (50.0–60.0 °C) and pressures (8.0–14.0 MPa) by a column sampling method. By using a high-pressure quartz spring method, the adsorption amounts of the binary PEA and CO 2 in silica were determined. The retention of PEA in the SSFL powder flavors was evaluated by a nitrogen-purging method. Results revealed that, compared with AC, silica had high loading of PEA (maximum 0.484 g/g) and showed better results in PEA preservation from loss at room temperature and control release at higher temperature; PEA suppressed the adsorption of CO 2 at relatively high pressure. Discussion indicated that precipitation and adsorption contributed to the high loading of PEA in silica, while adsorption mainly contributed to that in AC. [ABSTRACT FROM AUTHOR]

Alumina was synthesized from Al(NO 3 ) 3 , AlCl 3 and Al 3 (SO 4 ) 2 with NaOH, and from NaAlO 2 with HNO 3 by addition of acidic solution to alkaline solution with a syringe pump. The as-produced Al 2 O 3 precursors were supercritically dried and calcined at 500 °C to obtain mesoporous γ-alumina material. Results showed that all the inorganic aluminum salts could be used to synthesize high pore volume γ-alumina by controlling the precursor addition rate at room temperature and supercritical CO 2 drying. However, the γ-alumina with the largest pore volume (5.4 cm 3 /g), BET surface area (423.7 m 2 /g) and pore size (37.8 nm) was obtained using Al(NO 3 ) 3 and NaOH. This γ-alumina was further used as a support for Fe-based catalyst with hydrogen peroxide to produce hydroquinone and catechol in the phenol hydroxylation reaction in 30 min at 80 °C. The conversion of phenol was 53.4% whereas the selectivity to dihydroxybenzenes-DHBs (hydroquinone-HQ and catechol-CAT) was as high as 96.2%, revealing that the larger pore volume takes effect in the γ-alumina as support for the Fe-based catalyst in the hydroxylation reaction, and that the γ-alumina may be a good candidate as the support for other important catalysts such as those used in the petroleum refining industry. [ABSTRACT FROM AUTHOR]

Highlights: [•] A high-pressure PLM approach was proposed and established. [•] Melt crystallization behaviors of two solutes in CO2 were studied. [•] High pressure CO2 accelerated the crystallization rates of the two solutes. [•] CO2 did not evidently affect the nucleation or growth patterns of the two solutes. [•] The crystallization behaviors of the two solutes were different from those of polymers in CO2. [ABSTRACT FROM AUTHOR]

Abstract: Adsorption of 2-phenylethyl alcohol (PEA) from supercritical CO2 onto silica aerogel was investigated. A monolayer to multilayer adsorption isotherm was observed, measured at 15.0MPa and 323.2K, from the PEA-unsaturated to PEA-saturated supercritical CO2, indicating the potential utility of the solute-saturated supercritical adsorption (SSA). The amount of PEA adsorbed on the silica aerogel with SSA at different temperatures and pressures was measured, and the release of PEA from the aerogel at 303.2K was also evaluated. A theoretical model for the SSA equilibrium was developed with the assistance of the adsorption isotherms of pure CO2 onto the silica and considering a three-phase binary system, where the two-dimensional van der Waals equation of state and the three-dimensional Stryjek–Vera modification of the Peng–Robinson equation of state were used respectively to describe the adsorbed phase and the bulk phases (vapor phase and liquid phase). Results showed that the model was capable of describing the adsorption behavior of the system with an average absolute relative deviation of 3.3%. [Copyright &y& Elsevier]

Abstract: A supercritical fluid-based method is proposed to produce coenzyme Q10 (CoQ10) nanoparticles. First, CoQ10/polyethylene glycol 6000 composite particles are prepared by a modified PGSS (particles from gas-saturated solutions) process with controlling the flow rate of the gas-saturated solution. Then, CoQ10 nanoparticles are obtained by dissolving the composite particles into water. The effect of experimental variables of the modified PGSS process, including pressure, temperature, flow rate of the gas-saturated solution, and mass fraction of CoQ10, on the CoQ10 particle size and particle size distribution was investigated. Results show that CoQ10 slurry product with a median diameter of 190nm and yield of 89.8% can be prepared at an optimum condition (operating pressure of 25MPa, operating temperature of 80°C, gas-saturated solution flow rate of 1.02mL/min, CoQ10 mass fraction of 40% and nozzle diameter of 100μm) via the supercritical fluid-based method. [Copyright &y& Elsevier]

Abstract: The first and last melting points (FLMP) method was employed to measure the melting temperature–composition () data at solid–liquid–gas (SLG) equilibrium for the naphthalene–biphenyl–CO2 system. Results show that the system''s phase diagram is simple eutectic under all investigated pressures (0.1, 3.0, 6.0 and 8.0MPa), and the system''s eutectic composition is almost constant. The () data measured with a high-pressure differential scanning calorimetry are in good agreement with these from FLMP. The semi-predictive model using solubility data (SMS) and the calculation model combining with GE models (CMG) for binary systems were extended to this ternary system. For the SMS model, the Peng–Robinson equation of state (PR-EoS) with the van der Waals one-fluid mixing rule was used to correlate the solubility data of the two solutes in CO2 to obtain the two interaction parameters k 12 and k 13 and calculate the fugacity coefficients of the solutes in the liquid and vapor phases; the UNIFAC method was also applied to the activity coefficient of the solutes in the liquid phase. For the CMG model, the PR-EoS combining respectively the MHV1, LCVM, and modified LCVM (mLCVM) mixing rules was applied to the fugacity coefficients of the solutes. Results show that the CMG model with MHV1 gives the best prediction of the system''s SLG equilibrium, while the SMS model and the CMG model with mLCVM provide comparable and acceptable results. [Copyright &y& Elsevier]

In this work, the high acidic crude oil deacidification study was performed with novel 1-alkyl-1,5-diazabicyclo[4.3.0]non-5-ene (DBN) based ionic liquids (ILs). Firstly, we took advantage of the systematic COSMO-RS (Conductor-like Screening Model for Real Solvents) calculations to screen the possible ILs with good acid extraction performance from the combinations of 94 cations and 56 anions. Four 1-alkyl-1,5-diazabicyclo[4.3.0]non-5-enium imidazolide ([DBN-R][IM]) ILs with varying alkyl chains were eventually identified and synthesized successfully. Their deacidification performances were tested experimentally and different factors, including the alkyl chain length, ILs/oil mass ratio, temperature, and the initial total acid number (TAN) value of the simulated acidic oil, were also studied in detail. The experimental results showed that [DBN-R][IM] exhibited excellent performances on naphthenic acids (NAs) removal and [DBN-Et][IM] could achieve 93% of NAs removal employing the ILs/oil mass ratio of 0.06 at room temperature for the acidic oil with the TAN value of 3.28 mg KOH/g. COSMO-RS analyses were also used to elucidate the unusual effects of the alkyl chain length and temperature on the NAs extraction performances. Additionally, a two-step deacidification strategy was proposed aiming at realizing more efficient NAs extraction. Finally, density functional theory (DFT) calculations were carried out and the independent gradient model (IGM) analyses were applied to the IL-NAs system to get insight into the deacidification mechanism of the ILs. [Display omitted] • Four ionic liquids were screened out theoretically from 5264 ionic liquids for naphthenic acids extraction. • Four novel 1,5-diazabicyclo[4.3.0]non-5-ene based ionic liquids were synthesized successfully. • Deacidification factors were experimentally investigated and analyzed theoretically. • A two-step deacidification strategy was proposed. • DFT calculations and independent gradient model analyses were performed to study the mechanism. [ABSTRACT FROM AUTHOR]

The mesoporous poly(N , N ′-methylene-bis(1-(3-vinylimidazolium)) chloride), labeled as PDVIm-Cl, with double anions (Cl−) and low monomer molecular weight was synthesized and applied in the adsorption of anionic dyes (acid orange 7 (AO7), sunset yellow (SY), reactive blue 19 (RB19), congo red (CR)). Due to the mesoporous structure, abundant Cl− and positively charged imidazole rings, the poly(ionic liquid) (PIL) exhibited superior adsorption ability towards anionic dyes. What is more, the RB19 adsorption by PDVIm-Cl could achieve the highest capacity (2605 ± 254 mg g−1) which was nearly twice higher than the maximum adsorption capacity of the previously reported materials. All the adsorption kinetic data and isotherms fitted well with the pseudo second-order model and Langmuir-Freundlich model. To better explore the practical potential of the PIL for dye adsorption, the adsorption under different pH values and column adsorption performances were also evaluated. Results showed that PDVIm-Cl exhibited high removal efficiencies for anionic dyes over a wide pH range (2−10). Also, the great reusability could be well demonstrated by the achievable continuous column adsorption-desorption process. It is worth mentioning that the regeneration could be realized with very little desorbent which was far less than the adsorption volume flowing through the column and the desorption efficiency was well maintained after three consecutive cycles. At last, the adsorption mechanism was explored by experiments combined with quantum chemical calculations and showed anionic dyes adsorption by PDVIm-Cl was a joint process dominated by the ion exchange, electrostatic interaction, hydrogen bond and π-π stacking. • PDVIm-Cl is capable to adsorb various anionic dyes with high capacities. • PDVIm-Cl shows unprecedented adsorption capacity of 2605 ± 254 mg g−1 for RB19 dye. • PDVIm-Cl could be used to adsorb different anionic dyes in a wide range of pH. • PDVIm-Cl can easily realize continuous column adsorption-desorption process. • The adsorption mechanism is studied by experimental and theoretical calculations. [ABSTRACT FROM AUTHOR]

Ion exchange membranes (IEMs) are widely used in various fields including ion-selective separation processes and fuel cells. However, synthetic IEMs with a high ion conductivity usually suffer a high swelling ratio in working surroundings. Herein we demonstrate a versatile strategy to develop novel microporous copolymers for the high-performance IEMs via combining merits of polymers of intrinsic microporosity (PIMs) and common functional polymers. As a sample, a series of PIM-1/PES copolymers are synthesized accordingly. These copolymers, other than many PIMs, exhibit a good solubility in common organic solvents including N -methyl-2-pyrrolidone (NMP), and are successfully applied to prepare the high-performance IEMs by chloromethylation and multi-cation crosslinking. The introduction of PIM-1 segments exhibits distinct advantages in the effective water management, swelling control and construction of well-developed ion channels. The resulting PIM-1/PES 0.50 anion exchange membrane (AEM), with an ion exchange capacity (IEC) of 1.075 mmol g−1, has a low swelling ratio of 11.0% and a high hydroxide conductivity of 87.6 mS cm−1 at 80 °C. The developed strategy has wide applications in the development of new IEMs materials. Image 1 • A strategy is developed to prepare microporous copolymers for high-performance IEMs. • The copolymers exhibit good solubility in common organic solvents including NMP. • The copolymers are easily grafted with functional groups for high-performance IEMs. • The PIM-1 segment favors to construct well-developed ion channels in the AEMs. • The prepared AEMs show the high ion conductivity and low swelling at low IEC. [ABSTRACT FROM AUTHOR]

Anion exchange membrane (AEMs) as a kind of important functional material are widely used in many fields including fuel cell, electrodialysis and water treatment. However, synthetic AEMs generally suffer a pernicious trade-off: high ion-conductive AEMs lack dimensional stability and vice versa. Herein we demonstrate a versatile strategy to prepare the AEMs with both high ion conductivity and excellent dimensional stability (i.e. , low swelling ratio) via hydrophobic crosslinking and introducing hydrophobic chains. The hydrophobic length of crosslinkers has great influence on construction of highly efficient ion channels in the AEMs. Amazingly, the hydrophilic poly (phenylene oxide) (PPO) AEM crosslinked by 1,8-diaminooctane has the highest hydroxide conductivity that is further improved to 157.2 mS cm−1 (10% increases) with a low swelling ratio of 12.9% at 80 °C by introducing hydrophobic PPO backbone. This AEM not only overcomes the trade-off between the ion conductivity and the dimensional stability of crosslinked AEMs, but also breaks the upper bound between the ion conductivity and the water uptake. The newly developed strategy of hydrophobic dual-modifications promises to be an effective approach to develop the high-performance AEMs. Image 1 • A novel strategy was developed by combining both hydrophobic crosslinker and chain. • The hydrophobic length of crosslinkers has great influence on ion channels of AEMs. • The hydrophobic chains increase ion conductivity and decrease the swelling ratio. • The formed AEM has the OH− conductivity of 157 mS cm−1 with a SR of 12.9% at 80 °C. • This work breaks the trade-off between ion conductivity and dimensional stability. [ABSTRACT FROM AUTHOR]