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Non-aqueous absorbents (NAAs) have attracted increasing attention for CO 2 capture because of their great energy-saving potential. Primary diamines which can provide high CO 2 absorption loading are promising candidates for formulating NAAs but suffer disadvantages in regenerability. In this study, a promising strategy that using tertiary amines (TAs) as proton-transfer mediators was proposed to enhance the regenerability of an aminoethylethanolamine (AEEA, diamine)/dimethyl sulfoxide (DMSO) (A/D) NAA. Surprisingly, some employed TAs such as N,N -diethylaminoethanol (DEEA), N,N,N',N'',N'' -pentamethyldiethylenetriamine (PMDETA), 3-dimethylamino-1-propanol (3DMA1P), and N,N -dimethylethanolamine (DMEA) enhanced not only the regenerability of the A/D NAA but also the CO 2 absorption performance. Specifically, the CO 2 absorption loading and cyclic loading were increased by about 12.7% and 15.5%–22.7%, respectively. The TA-enhanced CO 2 capture mechanism was comprehensively explored via nuclear magnetic resonance technique and quantum chemical calculations. During CO 2 absorption, the TA acted as an ultimate proton acceptor for AEEA-zwitterion and enabled more AEEA to form carbamate species (AEEACOO−) to store CO 2 , thus enhancing CO 2 absorption. For CO 2 desorption, the TA first provided protons directly to AEEACOO− as a proton donor; moreover, it functioned as a proton carrier and facilitated the low-energy step-wise proton transfer from protonated AEEA to AEEACOO−. Consequently, the presence of TA made it easier for AEEACOO− to obtain protons to decompose, resulting in enhanced CO 2 desorption. In a word, introducing the TA as a proton-transfer mediator into the A/D NAA enhanced both the CO 2 absorption performance and the regenerability, which was an efficient way to "kill two birds with one stone". [Display omitted] [ABSTRACT FROM AUTHOR]

Biphasic solvents with primary/secondary amines as the primary absorbent involve a high heat of reaction and low desorption efficiency, limiting their development. A tertiary amine-based biphasic solvent composed of diethylethanolamine (DEEA), 2-Amino-2-methyl-1-propanol (AMP), ethyl acetoacetate (EAA), and H 2 O (referred to as DEEA/AMP/EAA/H 2 O) was proposed, which exhibited superior low-temperature desorption performance and ultra-low regeneration energy. EAA was revealed to facilitate the low-temperature desorption by reducing the activation energy from 6.8 to 2.3 kcal/mol. When regenerated only by heating to 353.15 K, the CO 2 -rich phase showed a significant desorption efficiency of 88.2 %; the desorption capacity and desorption rate were even 2.23 times and 6.84 times higher than 30 wt% MEA at 393.15 K. Moreover, the desorption heat dominated by the deprotonation of tertiary amine was as low as 0.92 GJ/t CO 2 ; and low-temperature regeneration brought extremely low latent heat below 0.062 GJ/t CO 2. Thus, the total regeneration energy was as low as 1.16 GJ/t CO 2. In addition, EAA could trigger the phase separation and increase the absorption rate constant from 3.87 E−4 to 1.36 E−3 s−1, even higher than 30 wt% MEA. The addition of AMP further increased the CO 2 loading (4.34 mol/L) and CO 2 distribution (97.43 %) of the CO 2 -rich phase. [Display omitted] • This study proposed a tertiary amine diethylethanolamine-based biphasic solvent. • It's the first biphasic solvent with desired low temperature desorption performance. • The latent heat was 5 % of MEA, with a total regeneration energy of 1.16 GJ/t CO 2. • Ethyl acetoacetate reduce the energy barrier and enable low temperature desorption. • It showed greater desorption capacity and rate at 353 K than those of MEA at 393 K. Synopsis: A novel DEEA/AMP/EAA/H 2 O biphasic solvent was developed with excellent low-temperature desorption performance and extremely low regeneration energy. [ABSTRACT FROM AUTHOR]

[Display omitted] • The amine oxide membrane pore size was found to be reversibly tunable. • The "trade-off" effect of the membrane was interestingly eliminated by the introduction of side amine oxide. • These membranes showed good anti-fouling properties and stability after multi-acid/alkali cycle treatment. Creating advanced polymer membranes with adjustable pores for various separation methods has been challenging because of the lack of new materials with adaptable and reversible chemical structures. In this study, we designed membranes using polyarylene ether sulfone/amide tertiary amine (PAES/ATA) copolymerized with polyarylene ether sulfone and polyamide tertiary amine. These membranes incorporated amine oxide units into their molecular chains by oxidizing the TA unit in the PAES/ATA copolymer chain. Applying the oxidation process improved antifouling properties, with the oxidized membrane showing a permeance recovery rate (Frr) of 95.48 % and a total fouling ratio (R t) of 9.35 %. These units also functioned as switches, altering their charge in different pH environments, thereby allowing pore size adjustment in the membranes. Notably, with the formation of amine oxide, these membranes exhibited properties distinct from the traditional "trade-off" effect, which is a persistent challenge in membrane technology development. The permeance and rejection rate of these membranes demonstrated the "simultaneous rise phenomenon" following a facile oxidation treatment to form amine oxide. This study presents a novel approach to develop membranes with new functional and tunable filtration capabilities, potentially applicable in various separation processes. [ABSTRACT FROM AUTHOR]

Developing functional membranes with switchable pores for the separation of contaminants with different sizes has been challenging due to the lack of novel materials with adaptable and adjustable structures. Polymers containing the tertiary amine (TA) unit can be transformed via oxidation into amine oxide (AO) structure that can modulate the membrane pore size. In this study, new monomers containing pH-responsive TA units and diacyl chloride containing reducible thioether (-S-) groups were used to yield pore-size-adjustable membrane resin polyarylene sulfide sulfone amide/amide tertiary amine (PASSA/ATA) at room temperature. By varying the polymerization ratio of the reaction solution, membranes could be prepared directly through non-solvent induce phase separation (NIPS) method without extra treatment. By oxidizing the TA units to AO through acid condition (H 2 O 2 /H 2 SO 4 /CH 3 COOH), the PASSA/ATA membrane can be switched from ultrafiltration to loose-nanofiltration with the rejection of RO16 and rhodamine B increased from 18.4% to 34.3 % (pristine membrane) to 91.7 % and 98.5 %. The permeance and rejection rate of the oxidized membrane were found to recover to the initial state after alkali-treatment. The mechanism of the switchable pore size was elucidated by dissipative particle dynamics (DPD) simulations. Interestingly, the oxidized PASSA/ATA membrane showed good organic solvent resistance and in nanofiltration performance, as it was capable of retaining about 95 % of Congo red in N,N-dimethylformamide (DMF) with permeance of about 10 L m−2 h−1 bar−1. This work presents a facile and low-carbon approach to develop novel membranes with multiple filtration capabilities, potentially applicable in various separation processes. Switchable polyaryl sulfide sulfone amide membrane containing tertiary amine unit: oxidation and reversible acid-base treatment. [Display omitted] • PASSA/ATA membranes were fabricated with a facile and low-carbon route. • The membrane pore size could be reversibly adjusted from ultrafiltration to nano-filtration with different pH value. • The membranes were found to have good organic solvent resistance and nanofiltration performance after facile one-step oxidation. [ABSTRACT FROM AUTHOR]

Carbon dioxide utilization presents an important and topical research topic. However, the performance of catalysts needed for CO 2 transformations does not achieve the necessary levels for their widespread application. To this end, we decided to study non-aqueous condensations providing amine-functionalized silica catalysts, possibly active in CO 2 -epoxide cycloaddition reaction. While non-hydrolytic sol-gel method is well-known for its efficiency in providing highly porous Lewis and Brønsted acid metallosilicates, here we show for the first time its application for the preparation of silica-based catalysts containing basic groups. First, the reaction conditions were screened to reproducibly obtain porous materials with preserved amine moieties. These were identified as follows: silicon tetraacetate and bridging tertiary amine silanes as precursors, toluene as a solvent, and temperature between 160 and 180 °C. In such a way, materials with up to 776 m2 g−1 and 1.58 cm3 g−1 were obtained in one-step process, without any template, after conventional drying step. Next, the amine-functionalized materials were tested in CO 2 -epoxide coupling providing cyclic organic carbonates with high selectivity (>99 %) and moderate activity (up to 86 % epichlorohydrin conversion after 1 h at 120 °C and 10 bar CO 2). The characterization of spent catalysts revealed a presence of cyclic organic carbonates at the catalyst surface as well as conversion of tertiary amine groups to quaternary ammonium moieties. [Display omitted] • Amine functionalized silica with up to 776 m2 g−1 and 1.58 cm3 g−1 by non-hydrolytic sol-gel. • Template-free and catalyst-free one-step synthetic process. • Materials active in the CO 2 cycloaddition on epichlorohydrin, styrene oxide, and 1,2-butylene oxide. • Quaternization of amine sites observed in spent catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • Higher energy conformers detected on aerial interface of pure liquid DMP and its aqueous solution. • DMP disrupts surface water network of aqueous solution by both hydrogen bonding and hydrophobic interaction. • Protonated DMP ions present on air-solution interface when acid is added to bulk. • VSFG spectrum of DMP on air-solution interface is pH responsive. Dimethyl piperazine (DMP) is a weakly basic, cyclic, tertiary diamine. Being a saturated 6-membered ring, it may attain a number of energetically close conformational orientations in the ground state. In a particular environment, its conformational distribution depends on the stabilising factors present in the surroundings. Though soluble in water, it is expected to have substantial surface propensity due to presence of multiple –CH 2 and –CH 3 bonds. Detection of Bohlmann bands in the C–H stretch region of the Vibrational Sum Frequency Generation (VSFG) spectrum revealed that comparatively higher energy chair conformer with one axial and one equatorial –CH 3 bond is present on the pure liquid DMP-air interface. At the air-aqueous solution interface, those bands were found to disappear as the lone electron pair on N-atom is engaged in hydrogen bonding with water molecule. Due to this hydrogen bonding, the peak of "dangling free OH" bonds disappeared from VSFG spectrum of water molecules at air–water interface. Alongwith this hydrogen bonding, the hydrophobic nature of the –CH 3 bonds of DMP molecules cause disorganisation of native hydrogen bonded network of water molecules in the air–water interface. Structure and orientation of DMP is expected to be pH-responsive since the chemical conditions of the surrounding medium directly affect the extent of protonation of the amine group. Upon addition of HCl to the bulk, protonated DMP ions, too, could be detected on the air-solution interface by their VSFG spectrum which were considerably different from unprotonated DMP. As the bulk pH of solution changed towards more acidic, spectral features of VSFG spectra of DMP on the surface showed significant change, implying variation in the surface pH, as structure and orientation changes at different degrees of protonation. Since the VSFG spectral features of DMP was found to be pH-responsive, it can be utilised to ascertain the pH of any surface that has DMP absorbed on it. pH-sensitivity of the DMP molecules on air–water interface also suggest that orientation of headgroups will have some effect on the surface orientation of cationic surfactants with amine based headgroups. [ABSTRACT FROM AUTHOR]

• The degradants structures of BCV via hydrogen peroxide oxidation are elucidated. • The degradants structures of BCV from photo-oxidation are confirmed. • Plausible degradation mechanisms of BCV are proposed. Beclabuvir hydrochloride (BCV) is a marketed product for the treatment of hepatitis C viral infection. It contains functional groups such as indole, tertiary amine and amides. Forced degradation studies of BCV revealed different degradation profiles under photo and hydrogen peroxide oxidative conditions. Under the photo-oxidative degradation conditions, the tertiary amine on the piperazine ring was oxidized to form the degradants as the hydroxyl and des-methyl analogs of beclabuvir. However, under the oxidative condition using hydrogen peroxide, the indole ring was oxidized to form a typical kynuric degradant and two unexpected cyclohexyl rearranged diastereomeric degradants. The plausible mechanisms for the photo and hydrogen peroxide mediated oxidative degradation of beclabuvir hydrochloride are proposed. [ABSTRACT FROM AUTHOR]

We developed a method for the synthesis of alkynyl amides via the carbonylation of alkynoic acids and C-N activation of tertiary amines. The reaction of alkynoic acid and tertiary amine with carbon monoxide using a palladium catalyst in the presence of oxygen, KI, and K 3 PO 4 , gave the desired alkynyl amides in good yields. Image 1 • The C N bond activation of tertiary amines. • The decarboxylative aminocarbonylation with alkynoic acids. • Synthesis of alkynyl amides. [ABSTRACT FROM AUTHOR]

• Cellulose acetate RO membrane was bi-antibacterial modified under mild condition. • Bromoacetyl bromide and tertiary amine were introduced in turn. • Modifying affected membranes hydrophilic, electronegative and mechanical property. • N,N- dimethyloctylamine modifying led to the best comprehensive membrane performance. • Bactericidal rates of broad-spectrum antibacterial RO membrane were higher than 99.9%. In order to improve the antibacterial efficiency and spectrum of cellulose acetate reverse osmosis membrane (CA–RO), both quaternary ammonium and bromoacetyl groups were introduced into cellulose diacetate under mild conditions forming CA–RO with bi-antibacterial groups for seawater desalination. Bromoacetyl bromide and a series of tertiary amine were chosen as the modification agents respectively. The characterization results showed that both two antibacterial groups were successfully introduced with a certain density. The obtaining membrane had a less hydrophilic but more electronegative surface as well as improved mechanical property. The flux values increased firstly and decreased subsequently after twice modifications while the salt rejection rose. The membrane modified with N,N- dimethyloctylamine (DMOA) had the optimal comprehensive performance of flux and salt rejection. The antibacterial testing results indicated that the resulting RO membranes showed high antibacterial efficiency and broad-spectrum. Their bactericidal rates against gram-negative Escherichia coli (E. coli) and gram-positive Staphylococcus aureus (S. aureus) were more than 99.9%. [ABSTRACT FROM AUTHOR]

The present work aims to investigate if a novel self-cure system, mediated by tertiary amine ethyl 4-(dimethylamino)-benzoate (4E) and tooth mineral hydroxyapatite (HAp), would trigger polymerization of model adhesives based on a popular self-etch monomer, 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP). The effect of 4E and HAp contents on degree of conversion (DC), polymerization rate (Rp), and induction period (IP) was investigated. The occurrence of such self-cure phenomenon in adhesives that underwent prior inadequate light cure was also evaluated. Model self-etch adhesives were prepared by using a monomer mixture of 10-MDP with 2-hydroxyethyl methacrylate at1:1 wt ratio. 4E (0.3–1.3 wt%), and HAp (0.5–2 wt%) were added to the mixture. Benzoylperoxide and N,N-dihydroxyethyl-p-toluidine were used as conventional chemical-cure system, and trimethylbenzoyl-diphenylphosphine oxide as light-curing photoinitiator. The polymerization processes and mechanical properties of model adhesives were evaluated by real time ATR/FT-IR and nanoindentation, respectively. The 4E-HAp system successfully triggered self-cure of 10-MDP based model adhesives. DC, Rp and IP were apparently affected by both 4E and HAp contents. DC of self-cure of the model adhesives was much higher than that of the conventional chemical-cure system. 4E-HAp initiated self-cure further boosted DC to ∼100% regardless of prior light exposure, and significantly improved elastic modulus and hardness, thus provided a novel polymerization method to effectively salvage curing of the adhesives after inadequate light-cure. [ABSTRACT FROM AUTHOR]

Abstract KMnO 4 -mediated oxidative C N bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Abstract The curing reaction of the epoxy system "diglycidyl ether of bisphenol-A" (DGEBA) and the tertiary amine "2-[(2-dimethyl-amino)-ethoxy] ethanol" (DMAE), with different DMAE concentrations was studied by means of rheometric analysis using the Rubber Process Analyzer (RPA). A novel simple technique was introduced in order to allow the use of the RPA instrument in measuring the curing studies of quasi liquid reactants. It was found that the crosslinking degree; as measured by: a)- the maximum torque in the RPA analysis as well as by b)- the estimated molecular weight between crosslinks (Mc); increased with the DMAE concentration. Also, it was found that the curing reaction rate, increased with the DMAE concentration; greatly decreasing the time to gel point as well as the time to maximum torque. The degree of crosslinking, as taken from the crosslink density or by the molecular weight between crosslinks, increases roughly seven times as the tertiary amine (DMAE) concentration increases from 3 to 10 wt%. The activation energy of the crosslinking reaction was determined by plotting as an Arrhenius type equation, the log(Gel time) -vs- the inverse temperature, and it was found to be around 42.9 kJ/mol. Highlights • The kinetic curing reaction of an epoxy resin with 2-[(2-dimethyl-amino)-ethoxy] ethanol (DMAE) tertiary amine was determined. • It was possible to study the epoxy curing reaction by rheometric characterizations. • The crosslinking degree increased with the DMAE content. • An increment in DMAE content greatly decreases the time to Gel-time and the maximum torque in the rheometer (RPA). [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Tertiary amine activated cure in hydroxyl rich environment. • Primary mechanism is a zwitterion initiated anionic chain-growth polymerization. • Isoconversional times show slowing down and broadening of reaction at high T. • Temperature jumps illustrate cure history dependence of reaction rate. • Proton transfer results in high extent of reaction at gel - unusual for chain-growth. Abstract The curing of diglycidyl ether of bisphenol A (DGEBA) epoxy with diethanolamine (DEA) is studied. DEA has three reactive groups, a secondary amine hydrogen and two hydroxyls. The secondary amine reacts rapidly, forming an adduct containing tertiary amines, epoxides and hydroxyls. The epoxides and hydroxyls then react in the presence of the amines to crosslink and vitrify the epoxy in the "gelation" reaction. The gelation reaction, the subject of this study, is not simple. The reaction exhibits unusual dependencies on both temperature and degree of cure. Previously, the general mechanisms of this curing process were explored by a number of us. In the present paper, both differential scanning calorimetry (DSC) and isothermal microcalorimetry (IMC) are used to determine a number of characteristic times associated with the reaction. The characteristic times show that the reaction rate has different functional forms at different temperatures and extents of reaction. This results from the reaction rate not depending solely upon the temperature and over-all extent-of-reaction. The concentration of a number of auxiliary reactive species that are generated in the course of the reaction (as well as their mobility and steric hindrance) appear to be key factors in defining the reaction kinetics. The dependence of the final network structure on cure schedule for this type of tertiary amine activated reaction is then discussed in the context of the literature. Finally, in the Supplementary Material, Kamal-like functions are fit to the isothermal reaction kinetics, with the reader cautioned in applying the functions to non-isothermal cures. [ABSTRACT FROM AUTHOR]

[Display omitted] • Three deep eutectic solvents bound to tertiary amine sites were prepared. • mPEI-TDA (1:2) had large SO 2 absorption capacities within a short period. • mPEI-TDA (1:2) exhibited a high SO 2 /CO 2 absorption selectivity. • mPEI-TDA (1:2) showed good stability and recyclability in multicycles. Rapid and efficient absorption of SO 2 by deep eutectic solvents (DESs) is highly desirable but extremely challenging. In this work, novel DESs bound to several tertiary amine sites were synthesized by mixing methylated polyethyleneimine (mPEI) and tris(2-(2-methoxyethoxy)ethyl)amine (TDA) at different mass ratios (2:1, 1:1, and 1:2). The synthesized DESs with low viscosity achieved efficient SO 2 absorption. In particular, excellent absorption capacities were achieved within a short period (0.44 g·g−1 at 0.5 min and 0.75 g·g−1 at 1.0 min) by mPEI-TDA (1:2) at 293 K and 1 bar. The uptake results are superior to those of most DESs and ILs in the current literature. Furthermore, mPEI-TDA (1:2) had an excellent SO 2 /CO 2 selectivity up to 89.1 at 293 K and 1 bar. Moreover, the SO 2 absorption achieved using DESs is highly reversible since the absorption capacity did not decrease significantly even after 10 cycles (absorption at 293 K and 1 bar, desorption at 353 K and 0.1 kPa under vacuum for 2 h). Overall, this work indicates that designing a DES containing several tertiary amine sites with low viscosity can be an effective method for realizing fast and efficient desulfurization of flue gas. [ABSTRACT FROM AUTHOR]

Developing a new generation of polymer membranes with switchable pores for multiple separation processes remains challenging due to the lack of materials with reversible and adjustable chemical structures. Herein, amine oxide units were introduced in the chains of poly (arylene ether sulfone) via oxidizing the tertiary amine (TA) in poly (arylene ether sulfone)/amide tertiary amine (PAES/ATA) copolymer, and then served as switches to tune the pores of the prepared membranes. The smart membranes could be reversibly tuned between loose nanofiltration mode with water permeance of 178 L m−2 h−1 bar−1 and dye (e.g., Rhodamine B) rejection of 95%, and ultrafiltration mode, with water permeance of 650 L m−2 h−1 bar−1 and dye rejection of 55%, by cyclic acid-alkali treatment. The mechanism of the switchable pore size was elucidated by dissipative particle dynamics (DPD) simulations, and the results were in good agreement with experimental results. This study provides a novel and facile route to fabricate functional membranes with reversibly tunable and highly efficient filtration performance, which could be applicable to multiple separations. [Display omitted] • Amine oxide derived from tertiary amine had excellent pH stimulation response. • These amine oxide membrane pore size was found to be reversible and tunable. • These membranes showed good mechanical performance after multi-acid/alkali cycle treatment. [ABSTRACT FROM AUTHOR]

A tertiary amine-mediated highly regioselective aromatic nucleophilic substitution (S N Ar) protocol was developed in the assemblies of perfluorinated phtalimide with primary or secondary amines as inputs. Application of 1-methyl-4-hydroxypiperidine as additive, formation of the less favoured, bioactive regioisomer was facilitated, modifying their ratios from the initial 8–36% to 81–91%. After optimization, a facile gram scale syntheses were accomplished and isolated the desired analogues in up to 63% yield. [ABSTRACT FROM AUTHOR]

A novel rosin-based ester tertiary amine (RETA) with three hydrophilic groups and a rigid hydrophobic group was synthesized from rosin by Diels-Alder addition, acylation and esterification reactions. RETA was characterized by infrared spectroscopy (FT-IR) and proton nuclear magnetic resonance spectroscopy ( 13 C NMR). Results from testing surface tension, zeta potential, and transmission electron spectroscopy showed that RETA had unique pH responsiveness. RETA self-assembled into worm-like micelles, spherical micelles 130 nm in diameter and big spherical worm-like aggregates with diameter of 2 μm at pH = 5.76, 8.04 and 9.38, respectively. The critical micelle concentration (CMC) of RETA was 0.42 mmol/L, and the surface tension at CMC (γ cmc ) was 38.73 mN/m when pH was 8.04. The RETA had a potential application in delivering doxorubicin hydrochloride (DOX) due to the pH responsiveness. Self-assembly mixed systems of RETA and rosin-based phosphoric acid (DDPD) were designed to improve emulsification. The mixed systems had obvious synergistic effects and unexpected emulsification. The γ cmc and CMC of mixtures were 41.74 mN/m and 0.20 mmol/L, the size of mixture micelles increased up to 300 nm in the optimum molar ratio of RETA/DDPD (7:3) by TEM and cryo-TEM. It was worth noting that the mixture system formed vesicles in the RETA/DDPD molar ratio of 5:5. The stability time of emulsion with RETA and DDPD as emulsifier were only 63 s and 52 s respectively, but the stability time increased to 234 s in the optimum molar ratio. In addition, the formation mechanisms of micelles at different pH and in various mixtures were discussed in detail. What’s more, cytotoxicity results showed that the toxicity of RETA was lower significantly than that of lecithin, a food ingredient in egg yolk and soybean. The cell viability was more than 83% in the high concentration of RETA (4000 μg/ml). [ABSTRACT FROM AUTHOR]

Radioactive iodine may be released into off-gas streams during both, the normal operation and severe accident of nuclear power plant in both organic and inorganic forms. Methyl iodide formation results from the reaction between radioactive iodine and organic products (like paint and cable coatings) present within the containment. For the removal of methyl iodide (MeI) gas, activated carbon (AC) was impregnated with 2, 5, 8 and 10 wt% of hexamethylenetetramine (HMTA) and triethylenediamine (TEDA). Characterization of the raw and impregnated activated carbon (IAC) was done by XRD, SEM, Raman, BET and TGA. Removal efficiency of MeI was evaluated using breakthrough experiments by varying weight percent of TEDA and HMTA. Both TEDA and HMTA-rich AC exhibited significant MeI adsorption capacity. TEDA-IAC was more effective for the elimination of MeI which adsorbed maximum 473 mg/g at low temperatures, whereas HMTA-IAC with high porosity had a comparatively high adsorption capacity at high temperatures due to its stability as compared to TEDA-IAC and adsorbed maximum 245 mg/g MeI. When raw AC was compared to IACs, results demonstrated that adsorption capacity of MeI improved up to 64 % for TEDA and 54 % for HMTA impregnated ACs. Langmuir model was well fitted to adsorption equilibrium data, and second-order model explained adsorption kinetics. Thermodynamic parameters study confirmed that the reaction is exothermic and spontaneous in nature. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, a new category of copolymer was designed by side grafting of tertiary amines (TA) on polyaryl ether sulfone. The synthesized copolymers PES/ATA displayed superior thermal properties with a glass transition temperature of 200–225 °C. These copolymers with favorable film-forming properties were used to fabricate ultrafiltration membranes via a phase inversion approach. Surprisingly, it was found that the filtration performance of these resultant membranes could be reversibly tuned between a facile acid oxidation (CH 3 COOH:H 2 SO 4 :H 2 O 2 = 40:1:1) and alkali solution (solution of 20 wt% NaOH, immersed for 4–8 h) treatment. While the water flux of dye solution had a twofold reduction, the oxidized membranes showed distinctly enhancement of methylene blue rejection from 35% to 91.5% after oxidation treatment. Subsequently, alkali treatment of the oxidized membranes allowed their water flux to recover up to 89% as that of pristine membranes, and the methylene blue rejection can recover to almost the same as that of pristine membranes. This phenomenon was closely related to the introduced reactive TA units: the TA group in the polymeric membrane was converted into stimulus-responsive amine oxide (AO) unit, then its charge can be reversibly changed between the acid oxidation and alkali treatment, and that can be used to tune the electrostatic repulsion and further tuned the membrane pore size. In addition, compared with the polyarylene sulfone membrane, the mechanical properties of these membrane had almost no deterioration after several treatment cycle. This study supplies a novel and facile routine to fabricate functional membranes with reversible-tunable filtration properties. [Display omitted] • Tertiary amines can be facile oxidized to amine oxide which have typical excellent pH stimulation response. • These amine oxide membrane pore size was found to be reversible and tunable. • These membranes showed good mechanical performance after multi-acid-alkali cycle treatment. [ABSTRACT FROM AUTHOR]

A simultaneous cell disruption and lipid extraction method is developed for microalgal biodiesel production using a triethylamine/methanol solvent system. Individually, the pure solvents, i.e. triethylamine and methanol, do not exhibit significant enhancement in lipid extraction, but a 3:7 (v/v) triethylamine/methanol mixture exhibits the highest lipid extraction, corresponding to 150% of the conventional chloroform/methanol (2:1, v/v) solvent extraction. This extraction is equivalent to 92.5% of the total lipids, even when extracted from a wet microalgal biomass with a water content of 80%. The cell surfaces of the microalgae are significantly disrupted without using additional cell disruption reagents and without requiring energy-intensive equipment. The lipid mass transfer coefficient is 1.6 times greater than that of the chloroform/methanol solvent system. It is clearly demonstrated that triethylamine and methanol cooperate well for the cell disruption and lipid extraction. [ABSTRACT FROM AUTHOR]

The separation properties of Pt(IV) over Fe(III) in HCl solutions using N -2-ethylhexyl-bis( N -di-2-ethylhexyl-ethylamide)amine (EHBAA) were investigated and then compared with those using the conventional extractant tri- n -octylamine (TOA). Also, the structural analyses of Pt(IV) in both of the aqueous (HCl solution) and organic (EHBAA in n -dodecane–2-ethylhexanol solution) phases were performed with EXAFS spectroscopy. The extractability of Pt(IV) was much higher with EHBAA than with TOA in the studied HCl concentration range (0.2–8 M HCl); additionally, EHBAA selectively extracted Pt(IV) over Fe(III) under the condition of [EHBAA] ⩽ 0.1 M and [HCl] ⩽ 1 M. The Pt(IV) loading capacity of 0.1 M EHBAA was about 9.2 g/L (about 0.05 M). Most of the Pt(IV) extracted with 0.1 M EHBAA from 1 M HCl was stripped with 0.1 M NaOH; the co-extracted Fe(III) was selectively scrubbed with distilled water. The structural studies indicated that the Pt(IV) extracted with EHBAA from 1 M HCl formed an ion-pair complex, [PtCl 6 ]·(EHBAA·H) 2 . [ABSTRACT FROM AUTHOR]

• The relationship of amine type and density to CH 4 adsorption was mapped. • The role of CH 4 adsorption on selectivity as a factor of amine type and density was studied. • Secondary amines showed an optimal balance of heat of adsorption, capacity, and selectivity. In designing amine-incorporated adsorbents for CO 2 /CH 4 separation, it is essential to understand the individual effects amine moieties have on the separation of CO 2 /CH 4 mixtures. In this work, primary, secondary, and tertiary amines are moderately grafted on SBA-15 to examine factors affecting adsorption of CO 2 and CH 4. Materials were characterised by thermogravimetric and elemental analysis, and their performance was measured by volumetric and gravimetric gas adsorption. An amine density of 1.6–1.7 mmol/g in secondary and tertiary amines showed an equivalent CH 4 uptake of <0.04 mmol/g at 25 °C, while primary amines adsorbed 0.05 mmol/g, indicating stronger interaction forces with CH 4. In terms of selectivity, primary and secondary amines grafted at 1.3–1.4 mmol/g had similar values, unaffected by amine type. Adsorption results cross analysed with DFT simulations indicate similar binding energies for CH 4 by both amine moieties, concluding the facilitated access of gas molecules to primary amine moieties is the primary factor dictating degree of adsorption. At an amine density of ∼ 1.7 mmol/g for both primary and secondary amines, an increase in temperature from 25 to 40 °C at a CO 2 partial pressure of 40 kPa showed a decrease in CO 2 /CH 4 selectivity of only primary amines. Secondary amines are thus more selective amine moieties at these conditions. Furthermore, in isothermal adsorption–desorption conditions, moderately grafted secondary amines have an equal working capacity to primary amines. Both these qualities support secondary amines at moderate densities as candidates for adsorbent development in CO 2 /CH 4 separations. [ABSTRACT FROM AUTHOR]

Herein, we describe the impact of the introduction of tertiary amines as additive during the enzymatic kinetic resolution via deacylation of some arylalkyl acetates 1a-8a under promiscuous conditions. Two CAL-B preparations were examined: Novozym ® 435 and CHIRAZYME® L-2, c.-f. C2, lyo. The influence of the introduction of seven amines is checked: Triethylamine (Et 3 N), Pyridine, 4-Dimethylaminopyridine (4-DMAP), 1,4-Diazabicyclo[2.2.2]octane (DABCO), Cinchonine, Cinchonidine, Quinine and Quinidine; and that in two organic solvent: diisopropylether (DIPE) and tertiobutylmethyl ether (TBME). Among the examined amines, the use of DABCO as additive recorded the best results in terms of reactivity and selectivity. It was to be highlighted that this additive was reported as an enzyme activator for the first time in the enzymatic kinetic resolution via hydrolysis of racemic acetates under non-aqueous conditions. Both CAL-B preparations showed the same behavior in the presence of the chosen additives during the biodeacylation of the resolved acetates. No direct correlation between the p K a values of several used additives and the CAL-B activation rates has been revealed. An ideal enzymatic kinetic resolution was recorded with the acetate 4a (Conv 50% and E > >200). [Display omitted] • The use of tertiary amines as additive improves the efficiency of CAL-B during the deacylation of some arylalkyl acetates. • No direct correlation between the p K a values of several used additives and the CAL-B activation rates. • The DABCO is described for the first time as lipase activator under promiscuous conditions for the EKRs of racemates. [ABSTRACT FROM AUTHOR]

This work aimed at studying the formation and persistence of N-oxides transformation products (TPs) of tertiary amine drugs by combining laboratory and field studies relevant for surface water. A monitoring study using passive samplers was first achieved for assessing attenuation of selected pharmaceuticals and their related N-oxides and N-, O-dealkylated TPs (i.e., venlafaxine, tramadol, amisulpride and sulpiride) along a 1.7 km river stretch between two sampling sites. This study revealed the stability of tramadol-N-oxide, amisulpride-N-oxide and the fast dissipation of O-desmethylvenlafaxine-N-oxide, as well as the significance of N-oxidized TPs in comparison to N-dealkylated TPs and parent compounds in river. Lab-scale experiments were then implemented for a better understanding of their mechanisms of formation and degradation under aerobic water/sediment testing and under simulated solar photochemistry. N-oxidation reactions were always a minor transformation pathway under both degradation conditions with respect to N-and O-dealkylation reactions. The amount of generated N-oxides were similar for venlafaxine, tramadol and sulpiride and peaked in the 8.4–12.8% and <4% of their initial concentration (100 μg/L), during photodegradation and biodegradation experiments, respectively. Other transformation pathways such as hydroxylation and α-C-hydroxylation followed by oxidation to amide or dehydration were also identified. Investigated N-oxides TPs (except O-desmethylvenlafaxine-N-oxide) were found stable under solar photolysis and aerobic biodegradation with a very slight reverse reaction to parent compound observed for tramadol-N-oxide and amisulpride-N-oxide. Lab-scale degradation experiments were not able to anticipate the high occurrence levels of N-oxide compounds in the environment. This was most likely due to faster degradation kinetics and/or higher sorption to sediment of parent compounds and dealkylated TPs over N-oxide TPs, resulting in higher relative accumulation of the latter. [Display omitted] • N-oxide transformation products of tertiary amine drugs are persistent in river. • N-oxides exceeded N-dealkylated transformation products concentrations. • N-oxidation was a minor transformation pathway under lab-scale photo/biodegradation. • N-oxides derived from WWTP point source release rather than in-stream formation. • Lab-sacle experiments failed to predict the relevance of N-oxides in river. [ABSTRACT FROM AUTHOR]

A tertiary amine-based biphasic solvent, N,N-dimethylethanolamine (DMEA)/piperazine (PZ)/N-butanol (n -BuOH)/H 2 O, was proposed for energy-efficient CO 2 capture. Low energy-consuming deprotonation dominated the CO 2 desorption reaction, resulting in a Q rxn as low as 1.17 GJ/t CO 2. Combining with the significantly reduced Q sen and Q latent due to phase separation, an extremely low regeneration energy consumption (1.59 GJ/t CO 2) was obtained, which was only 39.8% of 30 wt% MEA, and lower than most of reported biphasic solvents. The addition of n -BuOH not only induced the phase separation, but also reduced the activation energy of the reaction between DMEA and CO 2. It worked together with PZ to improve the inherent slow absorption rate of DMEA to a comparable value with 30 wt% MEA. Although a decreased CO 2 loading in the total solution was detected because the addition of n -BuOH reduced the equilibrium constant from 3.82 E+2 to 8.98 E+1, this biphasic solvent still achieved high CO 2 -rich loading (4.23 mol/L), large desorption capacity (3.77 mol/L), and superior desorption efficiency (89.1% at 393.15 K) owing to the good phase separation and desorption properties. In addition, the corrosion rate of CO 2 -rich phase was only 1.35% of CO 2 -loaded MEA. This research provided a promising alternative absorbent for CO 2 capture. [Display omitted] • A tertiary amine-based biphasic solvent DMEA/PZ/ n -BuOH/H 2 O was proposed. • Low Q rxn (1.17 GJ/t CO 2) resulted in low Q reg (1.59 GJ/t CO 2), 39.8% of 30 wt% MEA. • The hydrogen bond was revealed to be the key factor triggering the phase separation. • Superior desorption capacity (3.77 mol/L) and efficiency (89.1%) were obtained. • The corrosion rate of CO 2 -rich phase was only 1.35% of CO 2 -loaded MEA. [ABSTRACT FROM AUTHOR]

Aqueous piperazine (PZ) blended with a tertiary or hindered amine combines the high CO 2 capacity of the tertiary or hindered amine with the fast rate of PZ. For flue gas CO 2 capture, the optimum pK a (that which offers the highest CO 2 cyclic capacity) of a mono-tertiary amine blended with PZ is 9.1. A generic Aspen Plus® model for PZ/tertiary amine was developed to predict the CO 2 vapor-liquid-equilibrium (VLE) from the pK a of the tertiary amine. The polarity of the tertiary amine also affects the CO 2 solubility of the PZ/tertiary amine. Hindered amines that form little carbamate show similar CO 2 VLE to tertiary amines with the same pK a , when blended with PZ. The CO 2 absorption rate of most 2.5 m PZ/2.5 m tertiary amines was slightly slower than 2.5 m PZ, probably due to the higher viscosity of the blends. [ABSTRACT FROM AUTHOR]

In this work, two tertiary amine-derived 4′-demethylepipodophyllotoxin (DMEP) conjugates (DC and DP) have been designed and synthesized using N , N , N ′-trimethyl- N ′-(4-carboxyl benzyl)-1,3-propanediamine (CPDM) and 4-(4-methylpiperazinomethyl)benzoic acid (PBA) as the targeting ligands. Both DC and DP exhibited strong in vitro cytotoxicity against small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC) cell lines. Cellular uptake efficiencies of DC and DP in human alveolar type II epithelial cells were significantly enhanced compared to DMEP and etoposide (VP-16), which were demonstrated to be concentration-, time- and energy-dependent. The active transport process of DC and DP might be mediated by organic cation transporters (OCTs). After systemic administration in mice, both DC and DP selectively accumulated in the lung, displaying the highest C max and AUC 0-t values of all tested tissues. Compared with DMEP and VP-16, DC and DP remarkably reduced the lung weight and the number of lung metastases of B16 melanoma in mice, and further prolonged the survival of tumor-bearing mice. Also, DC and DP exhibited comparable levels of cell cycle arrest and cell apoptosis. Furthermore, DC and DP demonstrated minimum toxicity towards vital organs and reduced gastrointestinal injury compared to DMEP and VP-16. Taken together, tertiary amine-derived moieties such as CPDM and PBA represent an efficient yet safe strategy to achieve lung-targeted drug delivery. [ABSTRACT FROM AUTHOR]

Treatment of an ynone-bearing azulene with tertiary amines resulted in transformation of the corresponding enaminone in high yield. The product ratio depended on the group at the structure of the amine. Investigation of the reaction mechanism indicated that treatment of the ynone with a tertiary amine gave the corresponding ammonium salt, followed by removal of an alkyl group to form the enaminone as the final product. The color of the enaminone was different than that of the ynone. [ABSTRACT FROM AUTHOR]

Direct α-alkylation of N -phenyl-tetrahydroisoquinoline with alkyl selenides of desired alkyl chain length and functionality is reported by photoredox catalysis. Construction of hexahydro pyrrolo- and pyrido-isoquinoline scaffolds along with indolines and tetrahydroquinolines is also described by intramolecular C(sp 3 )–C(sp 3 ) cross-couplings. [ABSTRACT FROM AUTHOR]

The extraction of rhenium(VII) from sulfate media by mixtures of tri-iso-octylamine (TIOA) and oxygen-containing reagents (2-octanol, 2-octanone, phenetole) has been examined. The synergistic effect for mixtures of TIOA and electron-donor reagents (ketone, ether) was established. The maximal synergistic enhancement factor (3.1) was observed for the “TIOA-2-octanone” mixture. Rhenium(VII) was extracted by this mixture as (R 3 NH)ReO 4 ∙ 0.2B. The maximal rhenium(VII) extraction was found at weak acid concentrations in aqueous phase (pH ~ 2–3), whereas the “TIOA-ketone” mixture could extract rhenium(VII) from weak alkaline media (pH ~ 7–9) in contrast to the “TIOA-alcohol” mixture. Effective stripping from the loaded “TIOA-2-octanone” mixture was achieved with a 3 mol/L NH 4 OH in 2–3 stages. [ABSTRACT FROM AUTHOR]

Cu I -catalyzed aerobic oxidation of tertiary amines as the substrate involves active radicals as the oxidized intermediates, in which the reduced intermediates, Cu I complexes, play a role of oxygen carriers to activate O 2 into the proton/electron/hydrogen-atom acceptor, while tertiary amines serve as the corresponding donor and afford alpha aminoalkyl carbon-centered radicals. Cu I -catalyzed oxidation of various tertiary amines using aerobic O 2 diffused from air as the ultimate oxidant and air-stable Cu II salts as the catalyst precursor was adopted as the chain initiation for radical polymerization of methyl methacrylate (MMA) in dimethylsulfoxide at 90 °C. The polymerization kinetics was monitored by gas chromatography, while the molecular weight and stereotacticity of PMMA were determined by gel-permeation chromatography and nuclear magnetic resonance spectroscopy. Triethylamine behaved as an efficient substrate while Cu II /2,2′-bipyridine complexes displayed a higher catalytic activity. The polymerization proceeded in a conventional fashion at a comparable rate even using several micromol of Cu II /2,2′-bipyridine complexes per liter, leading to syndiotactic-rich PMMA (syndiotacticity >55%) with an alpha-amino terminal moiety as the residue from the tertiary amine substrate, which was confirmed by UV-induced benzophenone-initiated radical polymerization using the so-obtained PMMA as the macro-sensitizer. The catalyst-performance analysis suggested that each molecule of Cu II /2,2′-bipyridine complexes could generate 3 × 10 2 propagating PMMA radicals in 3 h under optimal conditions. [ABSTRACT FROM AUTHOR]

In present study, 4-anilinoquinazolines scaffold, arylurea and tertiary amine moiety were combined to design, synthesize gefitinib analogs and discover novel anticancer agents. A series of 4-anilinoquinazoline derivatives ( 1 , 2 , 3 and 4 ) bearing arylurea and tertiary amine moiety at its 6-position were synthesized. Their antiproliferative activities in vitro were evaluated via MTT assay against A431 cell and A549 cell. The SAR of the title compounds was discussed. The compounds 2d , 2i and 2j with potent antiproliferative activities were evaluated their inhibitory activity against EGFR-TK. Compound 2j displayed potent inhibitory activity against EGFR-TK. In addition, compound 2j , at 50 mg/kg, can completely inhibit cancer growth in established nude mouse A549 xenograft model in vivo. These results suggest that the 4-anilinoquinazoline derivatives bearing diarylurea and tertiary amino moiety at its 6-position can serve as anticancer agents and EGFR inhibitors. [ABSTRACT FROM AUTHOR]

[Display omitted] • Intramolecularly-catalyzed epoxy vitrimers were designed, and their structure-property relationships were revealed. • Fast stress relaxation was achieved in these vitrimers, and the lowest relaxation time was 253 s at 180 °C. • Lower crosslink densities, higher molality of N(R) 3 and β -OH-COOR, and less bulky side chain led to faster stress relaxation. • Lower crosslink densities and less rigid side chains resulted in low-stiff vitrimers whose repair and remolding were better. Vitrimers are emerging dynamic polymers with exchangeable associated networks that can potentially be used as substitutes for conventional thermosetting polymers, whose healing and recycling are difficult. However, vitrimers have limited engineering applications due to their process complexity, the addition of extra catalysts, and the unclear factors that affect network rearrangement. Herein, epoxy vitrimers with intramolecularly-catalyzed transesterification were prepared by curing an ester-containing epoxy resin with diethylenetriamine and monoamines. The obtained diethylenetriamine-cured vitrimer had favorable tensile stress and modulus (60.86 MPa and 0.94 GPa). The intramolecularly-catalyzed vitrimers exhibited fast stress relaxation, and the relaxation time of monoamine-containing vitrimers was reduced to 253 s at 180 °C. The effect of structure variation on the vitrimers' properties was investigated by controlling the influencing parameters. The molality of the tertiary amine and β -hydroxy esters were directly proportional to faster stress relaxation. A higher crosslink density led to better mechanical properties and a higher glass transition temperature but retarded the stress relaxation. Side-chains with low steric hindrance accelerated the stress relaxation. Repair and remolding were more efficient in the vitrimers with lower stiffness. This study contributes to the design and practical applications of various epoxy vitrimers according to the desired final properties. [ABSTRACT FROM AUTHOR]

To explore low-pressure-driven nanofiltration (LPDNF) membranes with high permeate flux, a novel preparation route was proposed and investigated. First, an amphiphilic copolymer of poly (methyl methacrylate- co -dimethylaminoethyl methacrylate) (P(MMA- co -DMA)) was synthesized via free-radical copolymerization, and then blended with polyvinyl chloride (PVC) to fabricate precursor membranes via non-solvent induced phase separation (NIPS) process. Utilizing the quaternization and cross-linking reaction between p -xylylene dichloride (XDC) and tertiary amine units in PVC/PMMA- co -DMA precursor membranes, positively charged PVC/PMMA- co -DMA LPDNF membranes were obtained. Element alanalysis, X-ray photoelectron spectroscopy and scanning electron microscopy were employed to characterize the composition and morphology of the membranes. Effects of PMMA- co -DMA content and XDC concentration on the LPDNF membranes’ performance were studied and discussed. With the optimized condition, the NF membrane showed the highest salt rejection ( R ) and water flux ( J ), e.g., R MgCl 2 =89.1%, J MgCl 2 =22.1 L/(m 2 h) and R NaCl =45.1%, J NaCl =27.6 L/(m 2 h) at a pressure of 0.3 MPa. Besides, the rejections of the LPDNF membranes for inorganic salts increased in an order of Na 2 SO 4

An analysis of the kinetics of the epoxy–thiol reaction in a model stoichiometric system of monofunctional reagents, 3-mercaptopropionate (BMP) and phenylglycidylether (PGE) is reported. Benzyldimethylamine (BDMA) was employed as initiator in amounts ranging from 0.5 to 2 wt%. These formulations showed a kinetic behavior qualitatively similar to that of commercial adhesives and coatings formulated for a room-temperature cure. Isothermal DSC scans revealed the existence of a relatively long induction period preceding a fast autocatalytic reaction step. Dynamic DSC scans showed that the reaction was shifted to a lower temperature range by increasing the storage period of the initial formulation at 20 °C. This unusual kinetic behavior could be modeled assuming that thiolate anions, slowly generated during the induction period, initiated a fast autocatalytic propagation/proton transfer reaction. The kinetic model included a pseudo-steady state for the initiator concentration and an equilibrium reaction between epoxy and OH groups generated by reaction. A reasonable fitting of isothermal and dynamic DSC runs was achieved in a broad range of temperatures and amine concentrations. In particular, both the length of the induction time and the effect of the storage period were correctly predicted. [ABSTRACT FROM AUTHOR]

In this work, the stopped-flow technique was used to determine the kinetic parameters in terms of pseudo first-order rate constants ( k 0 ) for homogenous reaction of CO 2 into aqueous 3-diethylamino-1,2-propanediol (DEA-1,2-PD) solutions as temperature ranged from 293 to 313 K and amine concentrations ranged from 0.20 kmol/m 3 to 1.00 kmol/m 3 . It was found that k 0 increased with increasing amine concentration and temperature. Both the base-catalyzed hydration and the termolecular models were applied to interpret the experimental data. The results showed that the predicted CO 2 absorption rates exhibited good agreement with experimental data with an absolute average deviation (AAD) of 5.7% and 3.8% with respect to base-catalyzed hydration and the termolecular model, respectively. Furthermore, the p K a of DEA-1,2-PD was experimentally determined over the temperature range from 298 to 318 K. The relationship between experimentally measured second-order reaction rate constants ( k 2 ) and p K a was correlated using the Brønsted relationship. The results suggest that the Brønsted relationship for DEA-1,2-PD developed in this work can predict the reaction rate constant very well with an AAD of 0.8%. [ABSTRACT FROM AUTHOR]

A novel route was developed for the C3-formation of indoles using iodine as the catalyst. This transformation involves the cleavage of the C–N bond of tertiary amines by the Cross-Dehydrogenative Coupling reaction (CDC), and is well tolerated by a range of 1 H -indoles under aerobic conditions. Moreover, this method can be applied to gram-scale synthesis. [ABSTRACT FROM AUTHOR]

Binary mixtures of tertiary amine and acidic extractant showed synergism on the extraction of metals from a weak acid solution but there is uncertainty in identifying the solvent extraction reaction. The nature of interaction between the extractants in the binary mixture affects synergism in extraction reaction. In order to correlate the interaction with the physical properties of each extractant in the binary mixture, extraction of HCl from dilute solution in the absence/presence of rare earth elements (REEs) has been investigated. The extraction order of HCl and REEs was: Cyanex 272 + Alamine 336 > PC88A + Alamine 336 > D2EHPA > Alamine 336. The interaction between strong acidic extractant (D2EHPA) and Alamine 336 was strong enough to form an amine salt which took part in the reaction. In the binary mixture of weak acidic extractant (Cyanex 272 and PC88A) and Alamine 336, each extractant took part in the reaction independently. [ABSTRACT FROM AUTHOR]

To obtain ultrafiltration (UF) membranes with multi-functions in permeation, macromolecule sieving and specific heavy metal removal by adsorption, tertiary amine groups containing amphiphilic block copolymers (poly(methyl methacrylate- b -dimethylamino-2-ethyl methacrylate) (P(MMA- b -DMAEMA))) were designed and synthesized. Then the block copolymers were used to fabricate the tertiary amine block copolymer containing blend membranes with poly(vinylidene fluoride) (PVDF) via a non-solvent induced phase separation (NIPS) process. Hydrogen nuclear magnetic resonance ( 1 H NMR) and X-ray photoelectron spectroscopy (XPS) were used to characterize the bulk and the surface layer compositions of the prepared membranes. It was found that P(MMA- b -DMAEMA) stably retained in the blend membranes and greatly enriched onto the surface layers. The pH-dependent performances of the membranes were investigated in details. With the change of pH values, the surface hydrophilicity, water permeation, dextran sieving behaviors and hexavalent chromium (Cr(VI)) adsorption properties varied greatly. And the membrane performed obviously reversible pH-dependent property. From the results, a feasible method could be inferred for fabricating UF membranes with tunable filtration, macromolecule sieving and anion adsorption properties under different pH conditions. [ABSTRACT FROM AUTHOR]

• A new extended thermodynamic model was developed for CO 2 absorption in aqueous 2-dimethylamino-2-methyl-1-propanol solution. • The CO 2 equilibrium solubility was investigated at different temperatures with various CO 2 partial pressures. • The CO 2 absorption heat was evaluated in aqueous 2-dimethylamino-2-methyl-1-propanol solution. In this work, CO 2 equilibrium solubility in aqueous 2-(dimethylamino)-2-methyl-1-propanol (2DMA2M1P) solution was investigated by varying temperature, CO 2 partial pressure and amine concentration. Dissociation constant (p K a) and CO 2 absorption heat of 2DMA2M1P were calculated. Results show that the CO 2 equilibrium solubility increases with the CO 2 partial pressure but decreases with the increase of temperature. It was also revealed that the CO 2 equilibrium solubility declines when the concentration of 2DMA2M1P increases from 1 to 2 mol/L. In addition, a new extended C f model was proposed for predicting the CO 2 equilibrium solubility, and the predicted results show a good agreement with the experimental measured data with an average absolute deviation (AAD) of 2.08%. Furthermore, the proposed model was validated with the published data of tertiary amines, and the results indicate that the developed model has a good universality in predicting the CO 2 equilibrium solubility. Finally, a comparison with other reported amines was also made in terms of the CO 2 equilibrium solubility and the CO 2 absorption heat. All of them proved that the 2DMA2M1P could be a competitive amine solvents for CO 2 capture. [ABSTRACT FROM AUTHOR]

An I 2 -promoted 3-formylation of free ( N – H ) and N-substituted indoles with tetramethylethylenediamine (TMEDA) and H 2 O as the carbonyl source is achieved, providing 3-formylindole in moderate to excellent yields with good functional group tolerance. This procedure represents an exceedingly attractive alternative to the traditional formylation methods. [ABSTRACT FROM AUTHOR]

In order to advance our project to explore a new archetype of foldamer that preferentially folds in water, we designed two types of tri-functional building blocks with increasingly favorable ketone deprotection properties. Both were selected for their ease of synthetic access and the availability of bulk starting material. While the first building block proved unsuitable for efficient coupling by reductive amination, the second gave rise to almost quantitative yields according to mass spectral monitoring. It was thus effectively turned into a protected dimer and a tetramer. Although their subsequent purification prior to exhaustive ketone deprotection was preparatively impractical in view of their high polarity/water solubility, the stage is now set for transfer of the oligomer synthesis onto the solid phase on resin in view of the efficient five-step synthetic access from affordable bulk material, the favorable deprotection properties, the perspective for introduction of a variety of backbone substituents, and the possibility to protect the amine terminus by Boc or Fmoc protection. [ABSTRACT FROM AUTHOR]

Highlights: [•] The surface of mesoporous silica SBA-15 was modified with DMAPTS in scCO2. [•] Grafting on silica SBA-15 increased with time and DMAPTS concentration. [•] Surface area and pore diameter decreased as DMAPTS grafting increased. [•] scCO2 process is faster and yields a higher grafting density than the method using toluene. [ABSTRACT FROM AUTHOR]

Highlights: [•] A structural model describing the epoxy homopolymerization with tertiary amines is presented. [•] Expressions for relevant pre-gel and post-gel statistical averages are derived. [•] The effect of initiator regeneration and chain transfer is analyzed. [•] Protic impurities have a relevant role on the network build-up. [ABSTRACT FROM AUTHOR]

Highlights: [•] Tertiary amine grafted pore-expanded MCM-41 was found to be highly selective for SO2 adsorption on in presence of CO2. [•] High adsorption capacity of 2.19mmol SO2/g at room temperature with 1% SO2. [•] Adsorption capacity increased threefold under humid condition. [•] The adsorbent was completely regenerated thermally after exposed to dry or humid SO2. [ABSTRACT FROM AUTHOR]

Abstract: Different diluents including 1-decanol, 1-octanol and 2-ethyl-1-hexanol and kerosene have been evaluated in extracting acetic acid from the treated prehydrolysis liquor (TPHL) by triisooctylamine (TIOA) or trioctylamine (TOA). Diluent played an important role in recovering acetic acid from the TPHL, thus affecting the extraction equilibrium and extraction efficiency. Polar diluent like 1-decanol, 1-octanol and 2-ethyl-1-hexanol showed better performance than the nonpolar diluent kerosene. The maximum extraction efficiency was 68.79%, which was from 2-ethyl-1-hexanol. The organic solvent was regenerated and extracted HAc was recovered by aqueous sodium hydroxide. The regeneration efficiency can be improved by increasing molar ratio of sodium hydroxide to HAc. [Copyright &y& Elsevier]

Polyacrylonitrile fiber supported bisquaternary ammonium salts with varying interchain quaternary ammonium (QA) to tertiary amine (TA) ratio, counter ions and linker groups were prepared and characterized by TGA, FTIR, XPS, XRD, SEM, EA and water contact angle. The functionalized fibers were used to catalyze three-component reaction (3CR) and tandem deacetalization-3CR for the synthesis of pyrano[4,3- b ]pyrans, pyrano[3,2- c ]chromenes and pyrano[3,2- c ]quinolines in ethanol-water mixture. Under varying reaction conditions such as time, temperature, catalyst amount and solvents, the catalytic ability of the prepared fiber catalyst was investigated. Under the optimum conditions, the bisquaternary ammonium fiber with acetate counter ion and an interchain QA to TA ratio of 1:1 (PAN BQAc F) showed the best catalytic activity among the prepared fiber catalysts, and it can be used for 10 runs consecutively with only a slight depreciation in catalytic activity. Interestingly, PAN BQAc F can efficiently catalyze tandem deacetalization-Knoevenagel reaction and the relevant novel tandem deacetalization-3CRs for the synthesis of pyran-annulated heterocycles. In the tandem deacetalization reactions, the acetate ion plays an important role of facilitating proton transfer, which makes PAN BQAc F a cooperative and reusable heterogeneous catalyst. [Display omitted] • Novel tandem deacetalization-three component reactions were catalyzed successfully. • Performance depends on ratio of bisquaternary ammonium to tertiary amine moieties. • BQA moiety aids in-situ acid-base property, hydrophilicity and polarity of the fiber. • Excellent catalyst reusability was achieved up to 10 runs with high yields. [ABSTRACT FROM AUTHOR]

Highlights: [•] Lactic acid was extracted from aqueous solution using liquid emulsion membrane. [•] n-Trioctylamine and heptanes were used as carrier and organic solvent, respectively. [•] Optimization of conditions for lactic acid extraction. [•] Optimized conditions resulted in more than 95% recovery of lactic acid. [Copyright &y& Elsevier]