Separation of organic mixture is an inevitable process in most modern industrial processes. In the quest for a more sustainable and efficient separation, solvent-resistant nanofiltration(SRNF) has emerged as a promisi...Separation of organic mixture is an inevitable process in most modern industrial processes. In the quest for a more sustainable and efficient separation, solvent-resistant nanofiltration(SRNF) has emerged as a promising answer. This is because SRNF is a membrane-based process which offers the key advantages of high efficacy and low energy intensity separation. In particular, polymer-based membranes can offer compelling opportunities for SRNF with unprecedented cost-effectiveness. As a result, intensive research efforts have been devoted into developing novel polymer-based membranes with solvent-resistant capacities as well as exploring potential applications in different types of industries. In this review, we aim to give an overview of the recent progress in the development of the state-of-the-art polymer-based membranes for SRNF in the first section. Emerging nanomaterials for mixed matrix and thin film nanocomposite membranes are also covered in this section. This is followed by a discussion on the current status of membrane engineering and SRNF membrane commercialization. In the third section, we highlight recent efforts in adopting SRNF for relevant industrial applications such as food, bio-refinery, petrochemical, fine chemical and pharmaceutical industries followed by separations of enantiomers in stereochemistry, homogeneous catalysis and ionic liquids. Finally, we offer a perspective and provide deeper insights to help shape future research direction in this very important field of SRNF.展开更多
Six new asymmetric thiocarbonohydrazones 3a-3f were synthesized from following steps: firstly hydrazine hydrate reacted with carbon disulfide to form thiocarbonohydrazide (1) under microwave irradiation. Then compo...Six new asymmetric thiocarbonohydrazones 3a-3f were synthesized from following steps: firstly hydrazine hydrate reacted with carbon disulfide to form thiocarbonohydrazide (1) under microwave irradiation. Then compound (1) reacted with ketone and different aldehydes step by step to give 3a-3f with excellent yields under solvent-free conditions using microwave irradiation. Their structures have been determined by elemental analysis, IR, MS and ^1H NMR data. 2009 Qing Han Li. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.展开更多
A convenient and effective Paal-Knorr condensations of 2,5-hexanedione with most amines have been carried out at room temperature under solvent-free condition.Macroporous strongly acidic styrol resin(D001) as a novel,...A convenient and effective Paal-Knorr condensations of 2,5-hexanedione with most amines have been carried out at room temperature under solvent-free condition.Macroporous strongly acidic styrol resin(D001) as a novel,efficient,cost-effective,and reusable solid acid catalyst for the synthesis of pyrroles under the same conditions.The pyrroles were obtained in high yields in short reaction times.展开更多
Benzyltriphenylphosphonium tribromide(BTPTB) has been applied as an efficient catalyst for the preparation of bis(indolyl)-methanes (BIMs) via electrophilic substitution of indoles with aldehydes in the absence ...Benzyltriphenylphosphonium tribromide(BTPTB) has been applied as an efficient catalyst for the preparation of bis(indolyl)-methanes (BIMs) via electrophilic substitution of indoles with aldehydes in the absence of solvent.展开更多
A seeding strategy was developed in the preparation of cyclotetramethylenetetranitramine(HMX)explosive micro-particles by solvent-antisolvent method, to control their polymorphs from dangerous gamma(y) type to the des...A seeding strategy was developed in the preparation of cyclotetramethylenetetranitramine(HMX)explosive micro-particles by solvent-antisolvent method, to control their polymorphs from dangerous gamma(y) type to the desired and standard beta(β) form with the size distribution of <10.0 μm, by using a low concentration of β-HMX fine particles as micro-seed in the antisolvent medium. All products were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM), and dynamic light scattering particle size analyzer. In the next step, the effective factors on the sizes and morphologies of micro-particles in the presence and absence of two soft templates of poly(ethylene glycol)-400(PEG-400) polymer and coconut fatty acid diethanolamide(lauramide) surfactant were investigated. The results of experiments showed that using of water-soluble PEG-400 in the low antisolvent temperatures leads to the production of very spherical particles. Also non-ionic surfactant of lauramide, direct the crystal growth to needle-like structures. The advantages of this method are its capability for the simple production of β-HMX micro-particles in the large scale production process, with the various crystal structures and particles size distributions.展开更多
β-Amino esters were synthesized via ZnCl2-catalyzed Mannich-type reaction of imines and malonate esters under solvent-free conditions in 6 min. The β-amino ester was converted into the corresponding aspartic acid de...β-Amino esters were synthesized via ZnCl2-catalyzed Mannich-type reaction of imines and malonate esters under solvent-free conditions in 6 min. The β-amino ester was converted into the corresponding aspartic acid derivatives.展开更多
An efficient synthesis of 3,4-dihydropyrimidin-2(1H)-one derivatives using formic acid as catalyst, from aldehydes, β-ketoester and urea(thiourea) without solvent under the irradiation of microwave is described. Comp...An efficient synthesis of 3,4-dihydropyrimidin-2(1H)-one derivatives using formic acid as catalyst, from aldehydes, β-ketoester and urea(thiourea) without solvent under the irradiation of microwave is described. Compared with the classical Biginelli reaction, this new method has the advantage of good yields (77–94% for aromatic aldehydes) and short reaction time (3–8 min).展开更多
Oxalic acid was found to be an efficient catalyst for Pechmann condensation, which includes the reaction between phenols and β-keto esters leading to formation of coumarin derivatives. The advantages of present metho...Oxalic acid was found to be an efficient catalyst for Pechmann condensation, which includes the reaction between phenols and β-keto esters leading to formation of coumarin derivatives. The advantages of present methods are the use of cheap and easy available catalyst, solvent-free reaction conditions, better yields and shorter reaction time.展开更多
Six new N4-[bi-(4-fluorophenyl)-methyl]-piperazine thiosemicarbazones 3a-f have been prepared starting from [bi-(4-fluorophenyl)-methyl]-piperazine in solvent-free condition under microwave irradiation with excell...Six new N4-[bi-(4-fluorophenyl)-methyl]-piperazine thiosemicarbazones 3a-f have been prepared starting from [bi-(4-fluorophenyl)-methyl]-piperazine in solvent-free condition under microwave irradiation with excellent yields. Their structures have been determined by elemental analysis, IR, MS and 1H NMR data.展开更多
A simple and efficient procedure for the preparation of aryl- 14-H-dibenzo [aj]xanthenes by a one-pot condensation reaction of 2-naphthol and aryl aldehydes, in the presence of silica supported sodium hydrogen sulfate...A simple and efficient procedure for the preparation of aryl- 14-H-dibenzo [aj]xanthenes by a one-pot condensation reaction of 2-naphthol and aryl aldehydes, in the presence of silica supported sodium hydrogen sulfate (NaHSO4/SiO2) as a catalyst and in the absence of solvent has been developed. The present method offers several advantages such as excellent yields, short reaction time (10-30min), mild condition, simple work-up, and the use of a cheap and environmentally friendly catalyst with remarkable reusability.展开更多
Differently substituted benzimidazoles have been synthesized in very good yields in solvent-free conditions from o-phenylenediamine and aldehydes in the presence of BF3·OEt2 as a catalyst. The method is applicabl...Differently substituted benzimidazoles have been synthesized in very good yields in solvent-free conditions from o-phenylenediamine and aldehydes in the presence of BF3·OEt2 as a catalyst. The method is applicable to aromatic, unsaturated and aliphatic aldehydes and to substituted o-phenylenediamines without significant differences.展开更多
Sodium dihydrogen phosphate (NaH2PO4) efficiently catalyzes the condensation reaction of benzil, aldehydes, amines and ammonium acetate in a four-component reaction under solvent-free conditions. The reaction procee...Sodium dihydrogen phosphate (NaH2PO4) efficiently catalyzes the condensation reaction of benzil, aldehydes, amines and ammonium acetate in a four-component reaction under solvent-free conditions. The reaction proceeds rapidly and affords the corresponding tetra-substituted imidazoles in high yields. Also an efficient route was developed for the synthesis of tri-substituted imidazoles from condensation of benzil, aldehydes and ammonium acetate using NaH2PO4.展开更多
Solvent-free reactions of 1, 3-cyclohexanedione, 5, 5-dimethyl-1, 3-cyclohexanedione, 2, 4-pentanedione and ethyl acetoacetate with C60 in the presence of Mn(OAc)3·2H2O and ceric ammonium nitrate (CAN) under ...Solvent-free reactions of 1, 3-cyclohexanedione, 5, 5-dimethyl-1, 3-cyclohexanedione, 2, 4-pentanedione and ethyl acetoacetate with C60 in the presence of Mn(OAc)3·2H2O and ceric ammonium nitrate (CAN) under the high-speed vibration milling conditions afforded dihydrofuran-fused C60 derivatives. CAN is the better oxidant than Mn(OAc)3·2H2O in these mechanochemical reactions.展开更多
A variety of alcohols and phenols are efficiently acetylated with acetic anhydride in the presence of a catalytic amount of V(HSO4)3 in solution and under solvent free conditions. Mild reaction conditions, high yiel...A variety of alcohols and phenols are efficiently acetylated with acetic anhydride in the presence of a catalytic amount of V(HSO4)3 in solution and under solvent free conditions. Mild reaction conditions, high yields of the products, easy procedure and selective acetylation of alcohols and phenols in the presence of amines and thiols are the main advantages of this procedure.展开更多
Fifteen dihydropyrimidinthiones have been synthesized by microwave-assisted Biginelli reactions without any solvent or catalyst. The advantages of this novel protocol include the excellent yield, operational simplicit...Fifteen dihydropyrimidinthiones have been synthesized by microwave-assisted Biginelli reactions without any solvent or catalyst. The advantages of this novel protocol include the excellent yield, operational simplicity, short time and the avoidance of the use of organic solvents and catalysts.展开更多
The CO2-induced capillary blocking in anode flow field is one of the key adverse factors to reduce the performance of a micro-direct methanol fuel cell(l DMFC). In order to solve this problem, new polycarbonate(PC) fl...The CO2-induced capillary blocking in anode flow field is one of the key adverse factors to reduce the performance of a micro-direct methanol fuel cell(l DMFC). In order to solve this problem, new polycarbonate(PC) flow field plates with nested arrangement of hydrophilic fuel channels and superhydrophobic gas channels were designed,fabricated, and tested in this work. The gas channels were treated with solvent-induced crystallization using acetone solution. The superhydrophobicity with 160° water contact angle and 2° tilting angle was obtained on the PC substrates. A dummy cell using hydrogen peroxide decomposition reaction and a test loop were separately set up to evaluate the flow fields' performance. It was found that a 37 % pressure drop decrease can be obtained in the new serpentine flow field compared with that of the conventional one. The benefit of the new flow field to remove gas bubbles was also confirmed by an in situ visualization study on the dummy cell. Results show that the auxiliary superhydrophobic gas channels can speed up the discharge of the gas bubbles from the flow field, which will in turn improve the l DMFC performance.展开更多
Silica sulfuric acid was developed as a stable and efficient heterogeneous catalyst in organic synthesis. This solid acid catalyzed the regioselective ring opening of epoxides by thiocyanate anion to give thiocyanohyd...Silica sulfuric acid was developed as a stable and efficient heterogeneous catalyst in organic synthesis. This solid acid catalyzed the regioselective ring opening of epoxides by thiocyanate anion to give thiocyanohydrins as key intermediates in agricultural and pharmaceutical chemistry in high yields under solvent-free conditions.展开更多
An expeditious microwave-accelerated one-step synthesis of some new 2-(3,5-dimethoxy-4-methylphenyl)-5-aryl-1,3,4- oxadiazoles by reaction of 3,5-dimethoxy-4-methyl hydrazide with different carboxylic acids in prese...An expeditious microwave-accelerated one-step synthesis of some new 2-(3,5-dimethoxy-4-methylphenyl)-5-aryl-1,3,4- oxadiazoles by reaction of 3,5-dimethoxy-4-methyl hydrazide with different carboxylic acids in presence of thionyl chloride under neat conditions,has been achieved.展开更多
We studied the relationship between corona structure and properties of solvent-free Fe3O4 nanofluids. We proposed a series of corona structures with different branched chains and synthesize different solvent-free nano...We studied the relationship between corona structure and properties of solvent-free Fe3O4 nanofluids. We proposed a series of corona structures with different branched chains and synthesize different solvent-free nanofluids in order to show the effect of corona structure on the phase behavior, dispersion, as well as rheology properties. Results demonstrate novel liquid-like behaviors without solvent at room temperature. Fe3O4 magnetic nanoparticles content is bigger than 8% and its size is about 23 nm. For the solvent-free nanofluids,the long chain corona has the internal plasticization, which can decrease the loss modulus of system, while the short chain of corona results in the high viscosity of nanofluids. Long alkyl chains of modifiers lead to lower viscosity and better flowability of nanofluids. The rheology and viscosity of the nanofluids are correlated to the microscopic structure of the corona, which provide an in-depth insight into the preparing nanofluids with promising applications based on their tunable and controllable physical properties.展开更多
基金funding support from the Singapore Economic Development Board to Singapore Membrane Technology Center
文摘Separation of organic mixture is an inevitable process in most modern industrial processes. In the quest for a more sustainable and efficient separation, solvent-resistant nanofiltration(SRNF) has emerged as a promising answer. This is because SRNF is a membrane-based process which offers the key advantages of high efficacy and low energy intensity separation. In particular, polymer-based membranes can offer compelling opportunities for SRNF with unprecedented cost-effectiveness. As a result, intensive research efforts have been devoted into developing novel polymer-based membranes with solvent-resistant capacities as well as exploring potential applications in different types of industries. In this review, we aim to give an overview of the recent progress in the development of the state-of-the-art polymer-based membranes for SRNF in the first section. Emerging nanomaterials for mixed matrix and thin film nanocomposite membranes are also covered in this section. This is followed by a discussion on the current status of membrane engineering and SRNF membrane commercialization. In the third section, we highlight recent efforts in adopting SRNF for relevant industrial applications such as food, bio-refinery, petrochemical, fine chemical and pharmaceutical industries followed by separations of enantiomers in stereochemistry, homogeneous catalysis and ionic liquids. Finally, we offer a perspective and provide deeper insights to help shape future research direction in this very important field of SRNF.
基金the Natural Science Foundation of Southwest University for Nationalities (No.08NQZ002) for financial support.
文摘Six new asymmetric thiocarbonohydrazones 3a-3f were synthesized from following steps: firstly hydrazine hydrate reacted with carbon disulfide to form thiocarbonohydrazide (1) under microwave irradiation. Then compound (1) reacted with ketone and different aldehydes step by step to give 3a-3f with excellent yields under solvent-free conditions using microwave irradiation. Their structures have been determined by elemental analysis, IR, MS and ^1H NMR data. 2009 Qing Han Li. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
文摘A convenient and effective Paal-Knorr condensations of 2,5-hexanedione with most amines have been carried out at room temperature under solvent-free condition.Macroporous strongly acidic styrol resin(D001) as a novel,efficient,cost-effective,and reusable solid acid catalyst for the synthesis of pyrroles under the same conditions.The pyrroles were obtained in high yields in short reaction times.
文摘Benzyltriphenylphosphonium tribromide(BTPTB) has been applied as an efficient catalyst for the preparation of bis(indolyl)-methanes (BIMs) via electrophilic substitution of indoles with aldehydes in the absence of solvent.
基金financial support of this work by Malek-ashtar University of Technology(I.R.Iran)Grant No.1395064
文摘A seeding strategy was developed in the preparation of cyclotetramethylenetetranitramine(HMX)explosive micro-particles by solvent-antisolvent method, to control their polymorphs from dangerous gamma(y) type to the desired and standard beta(β) form with the size distribution of <10.0 μm, by using a low concentration of β-HMX fine particles as micro-seed in the antisolvent medium. All products were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM), and dynamic light scattering particle size analyzer. In the next step, the effective factors on the sizes and morphologies of micro-particles in the presence and absence of two soft templates of poly(ethylene glycol)-400(PEG-400) polymer and coconut fatty acid diethanolamide(lauramide) surfactant were investigated. The results of experiments showed that using of water-soluble PEG-400 in the low antisolvent temperatures leads to the production of very spherical particles. Also non-ionic surfactant of lauramide, direct the crystal growth to needle-like structures. The advantages of this method are its capability for the simple production of β-HMX micro-particles in the large scale production process, with the various crystal structures and particles size distributions.
基金the financial support form National Natural Science Foundation of China(No.20472116).
文摘β-Amino esters were synthesized via ZnCl2-catalyzed Mannich-type reaction of imines and malonate esters under solvent-free conditions in 6 min. The β-amino ester was converted into the corresponding aspartic acid derivatives.
文摘An efficient synthesis of 3,4-dihydropyrimidin-2(1H)-one derivatives using formic acid as catalyst, from aldehydes, β-ketoester and urea(thiourea) without solvent under the irradiation of microwave is described. Compared with the classical Biginelli reaction, this new method has the advantage of good yields (77–94% for aromatic aldehydes) and short reaction time (3–8 min).
文摘Oxalic acid was found to be an efficient catalyst for Pechmann condensation, which includes the reaction between phenols and β-keto esters leading to formation of coumarin derivatives. The advantages of present methods are the use of cheap and easy available catalyst, solvent-free reaction conditions, better yields and shorter reaction time.
基金Natural Foundation of Southwest University for Nationalities(No.234688).
文摘Six new N4-[bi-(4-fluorophenyl)-methyl]-piperazine thiosemicarbazones 3a-f have been prepared starting from [bi-(4-fluorophenyl)-methyl]-piperazine in solvent-free condition under microwave irradiation with excellent yields. Their structures have been determined by elemental analysis, IR, MS and 1H NMR data.
基金the K.N.Toosi University of Technology Research Council for financial support.
文摘A simple and efficient procedure for the preparation of aryl- 14-H-dibenzo [aj]xanthenes by a one-pot condensation reaction of 2-naphthol and aryl aldehydes, in the presence of silica supported sodium hydrogen sulfate (NaHSO4/SiO2) as a catalyst and in the absence of solvent has been developed. The present method offers several advantages such as excellent yields, short reaction time (10-30min), mild condition, simple work-up, and the use of a cheap and environmentally friendly catalyst with remarkable reusability.
文摘Differently substituted benzimidazoles have been synthesized in very good yields in solvent-free conditions from o-phenylenediamine and aldehydes in the presence of BF3·OEt2 as a catalyst. The method is applicable to aromatic, unsaturated and aliphatic aldehydes and to substituted o-phenylenediamines without significant differences.
文摘Sodium dihydrogen phosphate (NaH2PO4) efficiently catalyzes the condensation reaction of benzil, aldehydes, amines and ammonium acetate in a four-component reaction under solvent-free conditions. The reaction proceeds rapidly and affords the corresponding tetra-substituted imidazoles in high yields. Also an efficient route was developed for the synthesis of tri-substituted imidazoles from condensation of benzil, aldehydes and ammonium acetate using NaH2PO4.
基金We are grateful for the financial support from the National Science Fund for Distinguished Young Scholars(20125205)Anhui Provincial Bureau of Human Resources(2001Z019).
文摘Solvent-free reactions of 1, 3-cyclohexanedione, 5, 5-dimethyl-1, 3-cyclohexanedione, 2, 4-pentanedione and ethyl acetoacetate with C60 in the presence of Mn(OAc)3·2H2O and ceric ammonium nitrate (CAN) under the high-speed vibration milling conditions afforded dihydrofuran-fused C60 derivatives. CAN is the better oxidant than Mn(OAc)3·2H2O in these mechanochemical reactions.
基金this work by the research affair,University of Guilan,Rasht,Iran,
文摘A variety of alcohols and phenols are efficiently acetylated with acetic anhydride in the presence of a catalytic amount of V(HSO4)3 in solution and under solvent free conditions. Mild reaction conditions, high yields of the products, easy procedure and selective acetylation of alcohols and phenols in the presence of amines and thiols are the main advantages of this procedure.
基金the Natural Science Foundation of China(No.20272047,20572086)the Natural Science Foundation of Gansu Province(No.3ZS051-A25-001)Key Laboratory of Eco-Environment-Related Polymer Material(Northwest Normal University),Ministry of Education of China.
文摘Fifteen dihydropyrimidinthiones have been synthesized by microwave-assisted Biginelli reactions without any solvent or catalyst. The advantages of this novel protocol include the excellent yield, operational simplicity, short time and the avoidance of the use of organic solvents and catalysts.
基金financially supported by the National Natural Science Foundation of China (Nos. 51275076, 51475081)
文摘The CO2-induced capillary blocking in anode flow field is one of the key adverse factors to reduce the performance of a micro-direct methanol fuel cell(l DMFC). In order to solve this problem, new polycarbonate(PC) flow field plates with nested arrangement of hydrophilic fuel channels and superhydrophobic gas channels were designed,fabricated, and tested in this work. The gas channels were treated with solvent-induced crystallization using acetone solution. The superhydrophobicity with 160° water contact angle and 2° tilting angle was obtained on the PC substrates. A dummy cell using hydrogen peroxide decomposition reaction and a test loop were separately set up to evaluate the flow fields' performance. It was found that a 37 % pressure drop decrease can be obtained in the new serpentine flow field compared with that of the conventional one. The benefit of the new flow field to remove gas bubbles was also confirmed by an in situ visualization study on the dummy cell. Results show that the auxiliary superhydrophobic gas channels can speed up the discharge of the gas bubbles from the flow field, which will in turn improve the l DMFC performance.
文摘Silica sulfuric acid was developed as a stable and efficient heterogeneous catalyst in organic synthesis. This solid acid catalyzed the regioselective ring opening of epoxides by thiocyanate anion to give thiocyanohydrins as key intermediates in agricultural and pharmaceutical chemistry in high yields under solvent-free conditions.
文摘An expeditious microwave-accelerated one-step synthesis of some new 2-(3,5-dimethoxy-4-methylphenyl)-5-aryl-1,3,4- oxadiazoles by reaction of 3,5-dimethoxy-4-methyl hydrazide with different carboxylic acids in presence of thionyl chloride under neat conditions,has been achieved.
基金supported by National Natural Science Foundations(51073129 and50971104)Aeronautical Science Foundation of China(2010ZF53060)graduate starting seed fund of Northwestern Polytechnical University(Z2011012)
文摘We studied the relationship between corona structure and properties of solvent-free Fe3O4 nanofluids. We proposed a series of corona structures with different branched chains and synthesize different solvent-free nanofluids in order to show the effect of corona structure on the phase behavior, dispersion, as well as rheology properties. Results demonstrate novel liquid-like behaviors without solvent at room temperature. Fe3O4 magnetic nanoparticles content is bigger than 8% and its size is about 23 nm. For the solvent-free nanofluids,the long chain corona has the internal plasticization, which can decrease the loss modulus of system, while the short chain of corona results in the high viscosity of nanofluids. Long alkyl chains of modifiers lead to lower viscosity and better flowability of nanofluids. The rheology and viscosity of the nanofluids are correlated to the microscopic structure of the corona, which provide an in-depth insight into the preparing nanofluids with promising applications based on their tunable and controllable physical properties.