JOURNAL OF MEMBRANE SCIENCE
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2022
·
IF 10.53
Guangzhe Wang,Jinqiu Yuan,Junhui Zhao,Yafei Li,Runnan Zhang,Jianliang Shen,Xiaoyao Wang,Hong Wu,Ayman El-Gendi,Yanlei Su,Zhongyi Jiang
Porous framework materials hold great promise in tuning the chemical and physical structure of polyamide membranes for efficient nanofiltration . In this work, anionic covalent organic framework (aCOF) with abundant sulfonic acid groups was embedded into polyamide matrix via interfacial polymerization to modulate both membrane charge property and thickness for the removal of divalent ions. Benefiting from the high negative charged density, aCOF not only enhanced the membrane electronegativity from −25.6 mV to −71.5 mV but also slowed down the diffusion rate of piperazine by electrostatic interaction to decrease the membrane thickness from 93 nm to 18 nm. The enhanced electronegativity can intensify the charge exclusion to divalent anions (Na 2 SO 4 rejection above 97%), while the ultrathin structure endows membrane with high water permeance of up to 39 L m −2 h −1 bar −1 , about 2.4 times higher than that of pristine PA membrane. Our membranes provide a new path to rational design and controllable construction of high-performance nanofiltration membranes.
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高影响因子
FUEL
·
2022
·
IF 8.035
Zhongqi Ren,Hui Yu,Xiaojia Wu,Weidong Liu,Fan Zhang,Shichao Tian,Zhiyong Zhou
The separation of aromatics and aliphatic hydrocarbons is one of the most challenging and energy consuming operations in the petrochemical industry. In this work, two switchable solvents, 1,8-diazabicyclo[5.4.0]undec-7-ene imidazole ([DBU][Im]) and 1,1,3,3-tetramethylguanidine imidazole ([TMG][Im]), were synthesized and used for phase-change separation of toluene from n-heptane. The structures of these two switchable solvents were analyzed by 1 H Nuclear Magnetic Resonance (NMR) and Fourier Transform Infrared (FT-IR) spectroscopy. The miscibility of various components in these two ILs before and after treatment with CO 2 were studied, the results of which indicated that both these two switchable solvents could be utilized to achieve the effective separation of toluene from n-heptane. Among them, [TMG][Im] was preferable to be used at a low toluene content in the initial toluene/n-heptane system through feasibility study. The effects of extraction time, switchable solvent dosage and molar fraction of toluene on separation performance and the reusability were also investigated, demonstrating that [TMG][Im] could be used simply and feasibly for phase-change separating toluene from n-heptane and showed very good reusability and stability. Finally, the mechanism of reversible phase-change extraction process with [TMG][Im] was explored, indicating that the formation of [TMG][ImCO 2 ] could greatly increase the polarity of the switchable solvent, which is conducive to separating toluene and recovering [TMG][Im] by removing CO 2 .
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高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2022
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IF 4.778
Linbo Zhang,Bo Wang,Xianyu Jiang,Weihong Wan,Liangjun Yin,Simeon Agathopoulos,Hao Van Bui,Jianliang Xie,Li Zhang,Haipeng Lu,Longjiang Deng
Carbonyl iron (CI) powder (CIP) is highly considered for use as a microwave absorber because of the high activity as well as the high magnetic permeability and saturation magnetization ; yet, CIP is vulnerable to corrosion and aging in harsh conditions, such as salty and humid (e.g. ocean) or acidic environments, which limit the spectrum of its applications. The coatings can efficiently solve this problem. This study presents a novel simple approach for enhancing the electromagnetic wave absorption ability and the corrosion resistance of CI, which involves PDMS (polydimethylsiloxane) coating on the surface of CI particles using glycine (G) as a grafting agent. The properties of the resultant composite powder (G-CI/PDMS), such as thermal stability, corrosion resistance, hydrophobicity , and electromagnetic absorption , were determined. The thermal stability, hydrophobicity, and corrosion resistance of the G-CI/PDMS were enhanced, compared to CIP, ascribed to the barrier effect of PDMS. The electromagnetic parameters were reduced, but its electromagnetic wave absorption capacity was improved at specific frequencies and absorber thicknesses due to impedance matching. The polarization curves showed that the corrosion potential of the G-CI/PDMS was shifted to the positive direction and the corrosion current decreased by two orders of magnitude, compared to CIP.
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高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2022
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IF 5.518
Minjing Xu,Shuaishuai Ma,Jin Li,Meng Yuan,Jiamin Gao,Jinjuan Xue,Mingxin Wang
Oily wastewater causes serious pollution to the environment and has aroused widespread concern. Hereby, a novel, sustainable and hydrophobic 3D polydimethylsiloxane modified MoS 2 @biomass-derived carbon composite (PMC) was fabricated by simple hydrothermal carbonization , self-assembly, freeze-drying, and hydrophobic modification methods based on natural renewable resources. With a water contact angle of 147.2°, the PMC exhibits excellent hydrophobic and oleophilic properties and further processes high adsorption capacity for various organic solvents and oils, and the maximum volume adsorption capacity reached up to 98.5% (v v −1 ). Moreover, the PMC can maintain a high oil-absorption capacity even after 10 cycles, showing good recoverability and reusability. In addition, the as-prepared PMC also can be applied in the removal of water-soluble organic pollutant . Benefiting from its facile fabrication and excellent properties, the developed PMC can be a promising candidate for broad environmental applications.
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高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Wei Li,Xin Tang,Xing Han,Jiaqian Li,Ying Chu,Liqiu Wang
Hypothesis Although a lot of fluorinated coatings exhibit super-repellency to oils with low surface tensions, most of them are readily wetted by alcohols with high surface tensions, wherein the un-crosslinked fluorinated silane is expected to result in the failure of alcohol-repellency. Hence, the coating could be super-repellent to alcohols if the fluorinated silane is fully crosslinked by annealing. Experiments We fabricate the super-alcohol-repellent coating via covering sintered hollow silica nanospheres with perfluoroalkyl silane, followed by a simple two-step annealing. The surface chemistry of the coating is further examined by X-ray photoelectron spectroscopy. Findings The super-alcohol-repellent coating is remarkably super-repellent to diverse alcohols of surface tension from 20.9 to 64.8 mN m −1 and thus enables loss-free manipulation of alcohol droplets for amino acid detection. More importantly, we reveal that the annealing procedure could promote the condensation of silanol groups, showing the key role played by heat-mediated crosslinking of perfluoroalkyl silane in preparing alcohol-repellent coatings. Such annealing strategy is also proved to be effective for other fluorinated coatings to achieve super alcohol-repellency. Together with its super-repellency to virtually all liquids, the coating enables loss-free processing of diverse liquids, thus being of significant value for biological, chemical and medical applications.
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PubMed
高影响因子
THERMOCHIMICA ACTA
·
2022
·
IF 3.378
Song Feng,Qincheng Bi,Wenlin Liao
A novel densimeter based on a random temperature signal cross-correlation method was designed and constructed. Liquid densities of n -decane were measured at T = (293.2–493.5) K and p = (0.1–20.0) MPa. The expanded uncertainties in liquid density measurements are 1.16%, with a confidence level of 0.95 ( k = 2). This experimental study provides new n -decane densities to examine Lemmon's equations' accuracy at high temperatures and pressures, where few experimental densities are yet to be reported. The experimental data's average absolute deviation ( AAD ) and maximum absolute deviation ( MAD ) compared to the fitted data from Lemmon's equations are 0.15% and 0.43%, respectively. The liquid densities at high temperatures and pressures were fitted with a Tait-type equation. The physical meaning and temperature behavior of the Tait correlation's parameters were discussed. The average absolute deviation ( AAD ) between the experimental and calculated data from the Tait-type equation is 0.23%.
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高影响因子
TENSIDE SURFACTANTS DETERGENTS
·
2022
·Vol. 59
·期 1
·39-50
·
IF 1.058
Fuwen Tan,Xu Li,Jinxiang Dong
Fischer-Tropsch syncrude prepared via the Fischer-Tropsch synthesis (FTS) using a Fe-based catalyst is featured by its high content of linear α-olefins (C 5 –C 13 ). The utilization of C 6 –C 8 α-olefins for the synthesis of alkyl benzene sulfonate surfactants was performed in the present work via dimerization, benzene alkylation, and sulfonation. The effects of the reaction conditions on benzene alkylation over a trimethyl amine hydrochloride-acidic anhydrous aluminum chloride ionic liquid catalyst (Et 3 NHCl-AlCl 3 ) have been studied in detail using C 6 α-olefin dimers as a model alkylation agent. Under the optimal reaction conditions (molar ratio of AlCl 3 to Et 3 NHCl = 2, catalyst loading = 0.29 mol %, reaction temperature = 30 °C, and molar ratio of benzene to C 6 α-olefin dimer = 10) the conversion of the C 6 α-olefin dimer was 100% and the selectivity toward the mono alkylbenzene product was 91.0%. C 6 –C 8 α-olefin dimer alkylbenzene sulfonates (C 6 –C 8 DBS) were synthesized via sulfonation using chlorosulfonic acid and characterized using Fourier Transform Infrared (FT-IR) spectroscopy and Liquid Chromatography–Mass Spectrometry (LC–MS). The surfactant properties of the C 6 –C 8 DBS, including their equilibrium and dynamic surface tension, foaming, wetting and emulsifying capabilities, were closely explored and compared with a commercial linear alkylbenzene sulfonate (LAS). The limiting surface tension ( γ
CMC = 34.62 mN m −1 ) and critical micelle concentration (CMC = 2.15 mmol L −1 ) of C 6 α-olefin dimer alkylbenzene sulfonate (C 6 -DBS) were similar to those of LAS. Upon increasing the hydrocarbon chain length, the γ
CMC of C 6 -DBS, C 7 -DBS, and C 8 -DBS remained unchanged, while the CMC decreased. C 6 –C 8 -DBS exhibited foaming, emulsifying, and wetting properties comparable to LAS.
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高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2022
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IF 3.269
Hongru Zhang,Bingjie Huo,Mengya Sun,Rongli Shan,Peizhe Cui,Jingwei Yang,Yinglong Wang,Shiqing Zheng
For the extraction distillation process, the choice of entrainer is very important. Usually, the boiling point of the entrainer is higher than that of any of the components to be separated, while the mechanism of separation of azeotropic system with intermediate-boiling-point solvent as entrainer is not common. Taking the azeotrope of n-heptane and isopentyl alcohol as an example, the intermediate-boiling-point solvent of butyl acetate was determined as the entrainer. The experimental data of vapor–liquid equilibrium for the two systems of n-heptane isoamyl alcohol and n-heptane butyl acetate were analyzed. After the thermodynamic consistency test, the binary interaction parameters of three models were obtained by correlating and regressing the experimental data. The possibility and mechanism of the extraction of azeotropic system by the intermediate-boiling-point solvent were analyzed from the aspects of σ-profile, interaction energy and charge density by the principle of quantum chemistry and molecular dynamics. The results showed that the tendency of hydrogen bond between the intermediate-boiling-point solvent and the azeotropic system was different: one component interacted with each other in the form of hydrogen bond, and the other had no hydrogen bond. The mechanism of the intermediate-boiling-point solvent as the entrainer to separate azeotropic system was verified in the extractive distillation process.
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高影响因子
Advanced Composites and Hybrid Materials
·
2022
·Vol. 5
·期 2
·1268-1279
·
IF 11.806
Su Ji-Ling,Wang Juan,Fu Xiao-Na,Hou Li,Zhu Ping,Zhang Kai,Li Huo-Wang,Hou Ying,Liu Xiang-Yi,Xu Juan
This study explored the physicochemical properties, fatty acid compositions, and thermal characteristics of Malania oleifera seed oil (MOSO). Our data showed that the refractive index and specific gravity of MOSO at ambient temperature were 1.461 and 0.913, respectively. The oil content, acid, peroxide, saponification, iodine value, average molecular weight, and an average number of carbon–carbon double bond per triglyceride were 47.8%, 3.62 mg KOH/g oil, 4.61 meq O 2 /kg oil, 163.16 mg KOH/g oil, 104.28 g I 2 /100 g oil, 1031.51 g/mol, and 4.24, respectively. The fatty acid profiles of the methyl esters showed the presence of 96.09% unsaturated fatty acids and 2.16% saturated fatty acids. Nervonic acid (NA) was the major component (45.04%). These results suggested that MOSO is an excellent source of essential fatty acids and NA and may be used as a potential NA resource of health supplements and medicines. Graphical abstract
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高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2022
·
IF 10.53
Xu Zhang,Fangzhi Liu,Lusheng Xu,Zehai Xu,Chong Shen,Guoliang Zhang,Qin Meng,Congjie Gao
In this study, heterostructured MOF/lamellar talc composites was successfully synthesized by in-situ growth of zeolitic imidazolate framework-8 (ZIF-8) nanoparticles on acidified black talc (ABT) and introduced into polydimethylsiloxane (PDMS) matrix to prepare high-performance mixed matrix membranes (MMMs) via spin coating and thermal cross-linking. The submicron-size natural lamellar black talc (BT) was first explored as stable carrier to synthesize laminated composite with continuous MOF phase. Owing to its silica-oxygen tetrahedral structure, the resultant laminated composite presented good compatibility with PDMS matrix, avoiding the formation of interfacial defect between polymer and nanoparticles. Moreover, well-dispersed and continuous ZIF-8 nanoparticles on lamellar nanosheets had preferential adsorption effect for alcohol, enhancing the selectivity of membranes. The coupling effects of graphene-like lamellar structure from talc and sequential transport channels from ZIF-8 attributed to greatly enhance permeation flux. Various techniques such as FESEM, TEM, FTIR, XRD and EDS were applied to investigate the morphology and structure of composites and membranes, and pervaporation experiments were applied to probe the behavior of polymer-based composite membranes . High performance defect-free ZIF-8@ABT/PDMS MMMs exhibited excellent total permeate flux of 1711 g m −2 h −1 with very competitive separation factor of 41 for low concentration n-butanol recovery.
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高影响因子
Separations
·
2022
·Vol. 9
·期 3
·64
·
IF 3.344
Weibin Cai,Jiangyu Xie,Jingyu Luo,Xiaohan Chen,Mingqian Wang,Yujun Wang,Jiding Li
In this study, zeolite molecular sieve SAPO-34/polydimethylsiloxane (PDMS) mixed matrix membranes (MMMs) were prepared to recover propane. n-Octyltrichlorosilane (OTCS) was introduced to improve compatibility between SAPO-34 and PDMS, and enhance the separation performance of the MMMs. Physicochemical properties of the MMMs were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and water contact angle (WCA). Results showed that, after modification, alkyl chains were successfully grafted onto SAPO-34 without changing its crystal structure, particles in the MMMs were evenly distributed in the base film, and the hydrophobicity of the MMMs was enhanced. Moreover, the effects of SAPO-34 filling content, operating pressure, and feed gas concentration on the separation performance was explored. This indicated that the modification with OTCS effectively enhanced the separation performance of SAPO-34/PDMS MMMs. When the filling content of modified SAPO-34 was 15%, the maximal separation factor of 22.1 was achieved, and the corresponding propane permeation rate was 101 GPU.Keywords:MMMs;SAPO-34;PDMS;OTCS;propane recovery
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高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2021
·
IF 3.178
Zhang Youqi,Zhang Qinqin,Xin Hua,Lv Meiheng,Zhang Zhigang
Ionic liquids (ILs) have been extensively used in the separation of alkane + alcohol azeotropes as entrainers by liquid–liquid extraction. n-Butanol is widely added to the fuel because of its high calorific value and low volatility. It is of significance to recovery n-butanol from the azeotropic mixture containing n-butanol. In this work, ionic liquids, formed by combining 17 cations and 12 anions, were screened based on the COSMO-RS model. 1-ethyl-3-methylimidazolium dicyanamide [EMIM][DCA], 1-butyl-3-methylimidazolium dicyanamide [BMIM][DCA] and 1-hexyl-3-methylimidazolium dicyanamide [HMIM][DCA] were selected as entrainers. The liquid–liquid equilibrium data of the ternary system {n-heptane + n-butanol + [EMIM][DCA], n-heptane + n-butanol + [BMIM][DCA], n-heptane + n-butanol + [HMIM][DCA]} were measured at 298.15 K and 101.3 kPa. The quality of experimental data was tested by Othmer-Tobias, Bachman and Hand equations. The distribution coefficient (β) and selectivity (S) were calculated to evaluate the separation effect of the three ILs. The NRTL model was used to correlate liquid–liquid equilibrium experimental data. Finally, quantum mechanics calculations were performed to study the interactions between ILs and n-butanol through the reduced density gradient (RDG) function and quantum theory of atom in the molecule (QTAIM). The results of quantum chemistry calculation showed that the separation of n-butanol and n-heptane mixture by ionic liquids with [DCA] anions were dominated by hydrogen bonding. The research process is devoted to the development of green entrainers.
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高影响因子
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