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Solvent-based CO2 capture is a commonly employed post-combustion technique in processes involving absorber-stripper columns. This study focused on computer simulations with equilibrium- and rate-based modeling of CO2 capture using the amine solvents 2-amino-2-methyl-1-propanol (AMP), diethanolamine (DEA), and methyl diethanolamine (MDEA) and thermodynamic methods involving electrolyte NRTL models. The objective of this study was to understand the impacts of rate-based modeling, the type of amine, and thermodynamic methods on carbon capture. Within this study, the amine-based CO2 capture process from coal-power plant flue gas was studied using Aspen Plus modeling. Simulations were also conducted to determine the impact of thermodynamics and kinetics on the CO2 capture performance of the system. The results were analyzed on the basis of captured CO2 according to the solvents and models. The equilibrium approach was mostly invalid because of the oversimplified ideal stage assumptions through the column. The lowest carbon capture capacity was obtained with MDEA, while DEA yielded the best results. A sensitivity analysis with rate-based modeling showed the significant impact of the inlet CO2 composition. The amine-based CO2 capture process simulation included solution chemistry, electrolyte thermodynamics, rigorous transport property modeling, reaction kinetics, and rate-based multistage simulation, which could be applicable to different solvent systems. [ABSTRACT FROM AUTHOR]

This study employs the sol-gel auto combustion technique fueled by diethanolamine (DEA) to synthesize nanocrystalline magnesium ferrite (MgFe2O4) powders. During the study, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV–visible diffuse reflectance spectroscopy (UV-DRS), photoluminescence spectroscopy (PL), and vibrating sample magnetometry (VSM) were then used in order to determine how differing calcination temperatures influence the structure, chemical bonding, surface texture, morphology, optical, fluorescence, and magnetic properties of the resulting MgFe2O4 powders. The findings from the XRD and FT-IR analysis indicate that a single-phase spinel structure is formed in each of the MgFe2O4 samples. According to UV-DRS analysis, optimal calcination improved sample reflection levels in comparison to the visible and infrared spectral findings for the as-synthesized sample. The calcined samples exhibited bandgap energy (Eg) ranging from 2.11 eV to 2.14 eV, which was greater than the 2.02 eV of the as-synthesized sample. Examination of the PL spectra in the range of 380–700 nm revealed various light emission bands for the samples, which increased significantly in intensity at higher calcination temperatures. Furthermore, higher calcination temperatures also increased the magnetization of the MgFe2O4 spinel powders, while coercivity dropped significantly.

This study focuses on the synthesis and characterization of di-ethanolamine (DEA) and citric acid (CA) surfactant-assisted nanocrystals (NCs) of Zeolite ZSM-5, a known catalyst for hydrocarbon conversion to fuel. Chemical precipitation of NH4/ZSM-5 precursor yielded spherical NCs with average sizes of 8 nm for DEA/ZSM-5 and 6 nm for CA/ZSM-5, as revealed by XRD, SEM, EDX, UV-VIS, and FTIR analyses. UV-VIS analysis demonstrated remarkable optical properties in both NCs. The catalytic performance was evaluated by degrading methylene blue (MB) dye, a model pollutant, using hydrogen peroxide (H2O2) as a pro-oxidant at room temperature. Both DEA/ZSM-5 and CA/ZSM-5 NCs exhibited high MB degradation efficiency (DE), increasing with higher catalyst dosages (10-50 mg). Additional H2O2 (2-5 mL) did not significantly affect MB degradation, possibly due to H2O2's scavenging effect. The highest DEs, 96.02% for DEA/ZSM-5 and 96.06% for CA/ZSM-5, were achieved after 90 minutes, with optimized rates of 21.06 x 10-3 and 13.85 x 10-3 min-1, respectively. The degradation mechanism involves MB adsorption on the catalyst surface, followed by interaction with hydroxyl radical species (OH) to yield H2O, CO2, and other mineralized products. The NCs' small sizes, improved diffusivity, strong adsorption, and favorable catalytic properties contribute to their excellent performance. Notably, the study's low energy consumption and room temperature conditions make it a cost-effective method for environmental pollutant removal. [ABSTRACT FROM AUTHOR]

In this work, the kinetics study on the reaction between CO2 and tertiary amine catalyzed by zinc(II)‐1,4,8,11‐tetraazacyclotetradecane complexes (CM) and zinc(II)‐1,4,7,10‐tetraazacyclododecane complexes (CN) was carried out in a stopped‐flow device. The effects of the catalyst concentration, type of tertiary amines, and temperature on the reaction rate (ν) and catalytic activity (φ) were studied. It was found that the catalyst concentration, tertiary amine with higher pKa, and temperature had positive effects on ν. ν in N‐methyl diethanolamine solution with 10.0 mol m−3 CM and CN were 16.62 and 26.05 folds than the uncatalyzed ν at 298 K, respectively. φ increased with increasing catalyst concentration, decreasing temperature and tertiary amine's pKa. In addition, the kinetics behavior of tertiary amine‐CM/CN‐CO2 systems conformed to the Michaelis–Menten model. The activation energies in catalytic systems were 4%–15% lower than that in the non‐catalytic systems. [ABSTRACT FROM AUTHOR]

The purification of gaseous olefins, such as C2H4 and C3H6, requires the efficient removal of trace CO2 impurities. However, the development of ideal adsorbents with high CO2/olefin selectivity has remained a challenge. In this study, we synthesized a novel adsorbent, denoted as PEI/DEA@FS, by modifying fumed silica (FS) with a combination of polyethylenimine (PEI) and diethanolamine (DEA). At 298 K and 0.0004 bar, PEI/DEA@FS presented the highest CO2 adsorption capacity among previously studied adsorbents, with a value of 2.12 mmol/g. Notably, PEI/DEA@FS demonstrated very high ideal adsorption solution theory selectivity for CO2/C2H4 (>1010) and CO2/C3H6 (>107) at 298 K and 0.01 bar. Breakthrough experiments revealed its excellent separation performance, producing olefins (C2H4 and C3H6) with ultra‐high purity (>99.9%) from a CO2/olefin (1/99) mixture. Moreover, PEI/DEA@FS exhibited outstanding stability over 20 adsorption and desorption cycles, and its CO2 adsorption performance remained almost unchanged under 75% relative humidity in the feed stream. [ABSTRACT FROM AUTHOR]

We report the synthesis, structural characterization and magnetic properties of a series of Co(III)/Dy(III) complexes built up from an N-alkyl derivatized amino-alcohol ligand diethanolamine, functionalized with CnH2n+1 alkyl chains (n = 3, 4, 6, 8 and 10). While n = 3 afforded a butterfly {Co III2 Dy III2 } core, the other alkyl chains (n = 4, 6, 8) afforded hexanuclear triangle-in-triangle {Co III3 Dy III3 } complexes as shown by single-crystal X-ray determinations. Infrared spectroscopy allows us to characterize the C10 derivative complex, which did not crystallize. Magnetic ac susceptibility data collected below 10 K at driving frequencies up to 10 kHz under zero-dc field and up to 1 T provide insight into the SMM behaviour of the studied complexes. The characteristic time of the magnetization dynamics can be understood in terms of the competing Raman, Direct and Orbach-like mechanisms. A relationship between the magnetization dynamics within the family of complexes and the increasing alkyl chain length is discussed. [ABSTRACT FROM AUTHOR]

The adhesion properties of poly(glycidyl methacrylate (GMA)‐co‐butyl acrylate (BA)) statistical copolymers, synthesized by atom transfer radical polymerization (ATRP), are investigated employing three different curing agents or hardeners, such as diethanolamine (DEA), dicyandiamide (DICY), and 2‐cyanoacetamide (2‐CA) on copper, iron, brass, aluminum, and titanium metal surfaces. This work describes the treatment of the different surfaces, establishes the optimal curing conditions from differential scanning calorimetry (DSC) analysis of these novel adhesive systems, and evaluates the results of the single‐lap shear test for metal joints. Thus, by dynamic DSC measurements of the mixtures, a low curing temperature of 90 °C is defined when DEA is used as a curative; while systems based on DICY and 2‐CA require temperatures of 150 °C and 160 °C, respectively. In addition, the curing process of this controlled acrylic copolymer with DICY exhibits a singular behavior, possibly due to the curing reaction mechanism, where multiple epoxy‐amine ring‐opening polyaddition reactions take place between DICY's active hydrogens and epoxy groups of poly(GMA‐co‐BA). This latter curing system shows the highest adhesion features with lap‐shear strength at room temperature of 15.5 MPa, using copper as metallic substrate; however, the best results are obtained using 2‐CA as curing agent with aluminum and iron. [ABSTRACT FROM AUTHOR]

The near-azeotrope mixture of TFE and CO2 is an important concern urging the scientific community to develop new ways for TFE/CO2 separations. In this work, for the first time, Diisopropylamine (DIPA) and Diethanolamine (DEA) are used as solvents for separating a near-azeotropic mixture of CO2 and tetrafluoroethylene (TFE). The complete separation mechanism has been analyzed using ASPEN Plus process simulator. The binary parameters for CO2, TFE, DIPA and DEA have been taken from Cosmotherm software and the pure data parameters have been taken from the literature (NIST). The validation of the processes has been completed by comparing binary parameters with literature and pure parameters with the UNIFAC data. The separation of the near-azeotropic mixture of TFE and CO2 has been investigated where, both solvents can be proposed as good candidates, however DEA is proven better performer than DIPA. In addition, CO2 emissions analysis and Total Annual Cost (TAC) analysis has been performed for the payback period of 3, 5 and 7 years, where DEA proves to be most efficient for TAC while DIPA has less CO2 emissions. [ABSTRACT FROM AUTHOR]

Over the past 30 years, the increasing global temperature due to industrial emissions of greenhouse gases is considered as an immense threat to our environment which needs to be addressed. However, the number of industries has been increasing significantly over the past few decades, leading to the ever increasing emissions and worsening the air pollution situation. Carbon dioxide (CO2) is one of the major greenhouse gas contributing to the rapid climate changes and therefore, collective efforts are required to control its emissions. In this study, 20 experiments were conducted to study the solubility of CO2 in the mixture of two solvents diethanolamine and dimethylformamide (DEA and DMF). Design expert (DOE) software was used to design the solubility experiments in order to optimize the number of experiments and to develop a correlation between various variables such as temperature, pressure and solution concentration. The objective of this work was to measure the CO2 loading capacity in aqueous solutions of DEA and DMF at various operating conditions of temperature, pressure and solution concentrations. It was observed that by increasing the weight percent of DEA in the aqueous solution, solubility tends to increase. The maximum value of 0.7454 mol/mol of CO2 solubility was achieved at pressure of 8 bar and at temperature of 313.15 K which is found to be higher than the monoethanolamine (MEA). In addition to that important design property such as density was also measured at the wide range of temperature and concentrations. The new solubility and density data can be a useful contribution to design a better process to mitigate CO2 from various industrial streams. [ABSTRACT FROM AUTHOR]

The word “dendrimer” begun from two Greek words; i) Dendron: meaning tree, and ii) Meros: meaning portion or fragment. A dendrimer could be a Nanoparticle. It may be a branched macromolecule having a tall degree of atomic consistency, limit atomic weight, dispersion, particular estimate and shape characteristics, and a highly-functionalized, terminal surface. A arrangement of triazine based dendrimer vary in spacer length of center was synthesized by disparate strategy utilizing triazine trichloride and diethanolamine as branching units. Synthesized dendrimer were characterized by ghostly strategies such as FT-IR, 1H-NMR, 13C-NMR, ESIMass spectrometry and Basic examination. A number of dendrimer were synthesized utilizing diverse center in spacer length by dissimilar strategy. Characterization of these Dendrimer was palatably carried out by ghostly strategy. It was watched that chlorine terminated dendrimer were somewhat more thermally steady than hydroxyl ended dendrimer through TGA. On the total, warm solidness was expanded with increment in generation of dendrimer. Warm solidness was autonomous of center moiety or spacer length of dendrimer of same era. With increment within the dendrimer era Glass move temperature was too expanded and was too comparable to TRIAZINE dendrimer. [ABSTRACT FROM AUTHOR]

Heat‐stable salts (HSS), which trigger excessing foaming in absorber, are formed when protonated methyl diethanolamine (MDEA) reacts with the more acidic degraded products in the presence of dissolved oxygen (DO). The aim is to suppress the HSS formation in MDEA solution inaugurally employing a hybrid iron‐based nanoparticles (HINP) oxygen scavenger. It was discovered that the oxygen‐scavenging performance of a more cost‐effective 20 %Fe/HZSM5 was one‐fold higher than the 20 %Fe/MCM‐41. The former was verified for its superior structural properties. The Fe2+ on its surface first reacted with DO, preventing DO from oxidizing the MDEA. Consequently, the absence of hydroxyl radicals eliminated the potential of formic acid formation, hence suppressing the MDEA‐acid HSS formation. [ABSTRACT FROM AUTHOR]

A mononuclear square-planar CuII complex of (5-methyl-1H-pyrazol-3-yl)carbamate, [Cu(C5H6N3O2)2]·4H2O, was synthesized using a one-pot reaction from 5-methyl-3-pyrazolamine and copper(II) acetate in water under ambient conditions. The adsorption of carbon dioxide from air was facilitated by the addition of diethanolamine to the reaction mixture. While diethanolamine is not a component of the final product, it plays a pivotal role in the reaction by creating an alkaline environment, thereby enabling the adsorption of atmospheric carbon dioxide. The central copper(II) atom is in an (N2O2) square-planar coordination environment formed by two N atoms and two O atoms of two equivalent (5-methyl-1H-pyrazol-3-yl)carbamate ligands. Additionally, there are co-crystallized water molecules within the crystal structure of this compound. These co-crystallized water molecules are linked to the CuII mononuclear complex by O—H...O hydrogen bonds. According to Hirshfeld surface analysis, the most frequently observed weak intermolecular interactions are H...O/O...H (33.6%), H...C/C...H (11.3%) and H...N/N...H (9.0%) contacts.

Abstract The adhesion properties of poly(glycidyl methacrylate (GMA)‐co‐butyl acrylate (BA)) statistical copolymers, synthesized by atom transfer radical polymerization (ATRP), are investigated employing three different curing agents or hardeners, such as diethanolamine (DEA), dicyandiamide (DICY), and 2‐cyanoacetamide (2‐CA) on copper, iron, brass, aluminum, and titanium metal surfaces. This work describes the treatment of the different surfaces, establishes the optimal curing conditions from differential scanning calorimetry (DSC) analysis of these novel adhesive systems, and evaluates the results of the single‐lap shear test for metal joints. Thus, by dynamic DSC measurements of the mixtures, a low curing temperature of 90 °C is defined when DEA is used as a curative; while systems based on DICY and 2‐CA require temperatures of 150 °C and 160 °C, respectively. In addition, the curing process of this controlled acrylic copolymer with DICY exhibits a singular behavior, possibly due to the curing reaction mechanism, where multiple epoxy‐amine ring‐opening polyaddition reactions take place between DICY's active hydrogens and epoxy groups of poly(GMA‐co‐BA). This latter curing system shows the highest adhesion features with lap‐shear strength at room temperature of 15.5 MPa, using copper as metallic substrate; however, the best results are obtained using 2‐CA as curing agent with aluminum and iron.

A mononuclear square-planar CuII complex of (5-methyl-1H-pyrazol-3-yl) carbamate, [Cu(C5H6N3O2)2]⋅4H2O, was synthesized using a one-pot reaction from 5-methyl-3-pyrazolamine and copper(II) acetate in water under ambient conditions. The adsorption of carbon dioxide from air was facilitated by the addition of diethanolamine to the reaction mixture. While diethanolamine is not a component of the final product, it plays a pivotal role in the reaction by creating an alkaline environment, thereby enabling the adsorption of atmospheric carbon dioxide. The central copper(II) atom is in an (N2O2) squareplanar coordination environment formed by two N atoms and two O atoms of two equivalent (5-methyl-1H-pyrazol-3-yl)carbamate ligands. Additionally, there are co-crystallized water molecules within the crystal structure of this compound. These co-crystallized water molecules are linked to the CuII mononuclear complex by O--H⋯O hydrogen bonds. According to Hirshfeld surface analysis, the most frequently observed weak intermolecular interactions are H⋯O/O⋯H (33.6%), H⋯C/C⋯H (11.3%) and H⋯N/N⋯H (9.0%) contacts. [ABSTRACT FROM AUTHOR]

HRMS (ESI SP + sp ): I m i / I z i [M + H] SP + sp calcd for C SB 16 sb H SB 13 sb N SB 2 sb O SB 6 sb S: 361.0489; found: 361.0492. o -Tolyl 4-Nitrobenzenesulfonate (1k) General Procedure B using I o i -cresol (5.00 g, 45.8 mmol) afforded the title compound as a beige solid (11.63 g, 87% yield). Keywords: cross-coupling; homogeneous catalysis; transition metals; palladium; process chemistry EN cross-coupling homogeneous catalysis transition metals palladium process chemistry 3159 3171 13 09/11/23 20231004 NES 231004 Graph The palladium-catalyzed Suzuki-Miyaura cross-coupling can rightly be called a workhorse of organic synthesis, with widespread use in total synthesis, medicinal chemistry, and process development, among others. 1-([1,1'-Biphenyl]-4-yl)ethan-1-one (3a) General Procedure C using 4-acetylphenyl 4-nitrobenzenesulfonate ( B 1a b ) (1.00 g, 3.11 mmol) and 2-phenyl-1,3,6,2-dioxazaborocane ( B 2a b ) (713 mg, 3.73 mmol) afforded the title compound as a white solid (501 mg, 82% yield). SP 1 sp H NMR (500 MHz, DMSO- I d i SB 6 sb ): = 7.57 (s, 1 H), 7.08 (br s, 1 H), 6.27-6.28 (m, 2 H), 3.79-3.85 (m, 2 H), 3.74 (m, 2 H), 3.04-3.12 (m, 2 H), 2.78-2.83 (m, 2 H). 2-(Benzo[ b ]thiophen-2-yl)-1,3,6,2-dioxazaborocane (2o) General Procedure A using benzo[ I b i ]thien-2-ylboronic acid (1.5 g, 8.43 mmol) afforded the title compound as a white solid (1.63 g, 78% yield). [Extracted from the article]

Two cobalt(II) and copper(II) complexes, [Co2(PDCA)(µ-PDCA)(H2O)5]·2H2O (1); H2PDCA: pyridine-2,6-dicarboxylic acid and [Cu(DEA)(PDCA)] (2); DEA: diethanolamine, were prepared from a mixed ligand amine/PDCA methyl ester mixture and identified by elemental analysis, FT-IR spectroscopy and single-crystal X-ray diffraction. X-ray structure analysis of 1 revealed a binuclear octahedrally coordinated cobalt(II) complex formed by bridging a PDCA2− between metal centers. In the mononuclear complex 2, the copper atom has an octahedral geometry with CuN2O4 environment formed by one DEA and one PDCA2– ligands in mer form. The ability of the H2PDCA and DEA ligands along with complexes 1 and 2 to interact with ten selected biomacromolecules (BRAF kinase, CatB, DNA gyrase, HDAC7, rHA, RNR, TrxR, TS, Top II and B-DNA) were investigated by docking studies. The results showed that the studied compounds can bind to DNA and proteins. [ABSTRACT FROM AUTHOR]

Although plasticizing materials by modification with small‐molecular chemicals has been extensively utilized in the industrial community, processing poly(vinyl alcohol) (PVA) at high concentrations (CPVA) or with a high degree of polymerization (DP) remains challenging. Optimization the plasticizing conditions is one means of addressing this issue. In this study, two types of frequently used plasticizers, glycerol (GLY) and diethanolamine (DEA), are chosen to plasticize PVA resin with a DP of 2400. Both PVA/plasticizer films possess excellent optical transmittance and mechanical ductility, whereas the films blended with DEA exhibit higher strength than the PVA/GLY films. The viscosity variation in the temperature (Top)–CPVA space is monitored by real‐time viscous flow testing, demonstrating that DEA is more effective for reducing the viscosity of PVA, which should improve the processability, facilitating film‐forming from concentrated solutions. Furthermore, density functional theory calculations and molecular dynamics simulations illustrate that the PVA/DEA system has a lower binding energy, longer hydrogen bond length, and higher isotropic diffusion coefficient, indicating a stable hydrogen bond network and homogenous dispersion of the plasticizer, leading to good solution fluidity and mechanical performance. This study is significant for guiding the design and manufacture of optically transparent, high‐performance PVA films as polarizer precursor. [ABSTRACT FROM AUTHOR]

The surface activity of fatty amide surfactants synthesized under three different conditions are presented. Three reaction conditions, involving transesterification and amidation reactions, were performed. In the first condition, both reactions were conducted under environmental conditions. In the second, transesterification was conducted under supercritical conditions. For the third condition, both reactions took place under supercritical conditions. The transesterification reaction was performed in a preheated batch reactor at 523.15–623.15 K, a pressure of 8–25 MPa, and with a palm oil/methanol ratio of 1:4 v/v, adding supercritical CO2 as a reaction solvent. The amidation reaction was performed in the same reactor as that used for the transesterification at a temperature range of 523.15–623.15 K, a pressure of >8 MPa, and a stoichiometric oil/methanol ratio with 0.072 kg of diethanolamine. [ABSTRACT FROM AUTHOR]

The proposed article relates to synthesis and the study of new propargyl ester derivatives, and biostimulation activity of 4-(bis(2- hydroxyethyl)amino)but-2-yn-1-yl butyrate. Aminomethylation reactions of the obtained propargyl ester with ethanolamine and paraform were carried out in the presence of a catalyst. Copper salts were used as a catalyst. The structure of the new propargyl ester derivatives was established by IR and ¹H-, 13C- NMR spectroscopy. Comparative tests show that the test derivative of the drug 4-(bis(2- hydroxyethyl)amino)but-2-yn-1-yl butyrate showed a higher growth-promoting activity. [ABSTRACT FROM AUTHOR]

The effects of various organic additives, such as diethanolamine (DEA) and ethanolamine (EA), and variations in aging times on the formation and stability mechanisms of spherical aggregates of ZnO nanoparticles (NPs) prepared by using solvothermal synthesis were studied. The experimental results of the structural, morphological and optical properties monitored by using X-ray diffraction, field-emission scanning electron microscopy (FE-SEM) and UV-Vis spectroscopy were supported by quantum chemical calculations at the level of density functional theory (DFT). Understanding the mechanism of spherical ZnO aggregate formation and its stability by mimicking the processes at the computer level was achieved through theoretical simulations of the ZnO surface/additive interactions using (ZnO)36–DEA and (ZnO)36–EA models. The fine-tuned spherical aggregation of ZnO nanoparticles was driven by various interactions, in particular, strong O–H∙∙∙O and weak N–H∙∙∙O hydrogen bonds as controlling interactions. The calculated negative free release energy, ∆G*INT, indicates that the ZnO surface/additive interaction in diethanolamine media is a spontaneous exergonic process (∆G*INT = −7.73 kcal mol−1), whereas, in ethanolamine media, it is an unfavorable, slightly endergonic process (∆G*INT > 0). The presence of two strong O–H∙∙∙O hydrogen bonds and, at the same time, a weaker N–H∙∙∙O hydrogen bond is the key factor for the very good and long-term aggregate stability of ZnO NPs in DEA media. This integrated experimental–theoretical study highlights the stability and compactness of spherical ZnO aggregates of ZnO NPs, prepared in the presence of diethanolamine compared to ethanolamine media, and provides a promising method and flexible design of ZnO nanomaterials to improve their adsorptive and optical properties. [ABSTRACT FROM AUTHOR]

Background. It is known that the composite absorbent DEA + AVRP, used at gas processing plants, remains effective after 1.5 months of operation. Purpose. Improving the technology for purifying sulfur-containing natural and secondary gases using composite sorbents. Methodology. The physicochemical properties of sorbents have been studied, their structure has been studied using IR spectroscopy, potentiometry, photocolorimetry, gas chromatography, thermogravimetry, and MSS. Originality. A technology has been developed for the production of composite absorbents using synthesized polyelectrolytes based on bottom residues in the production of furan compounds with diethanolamine and methyldiethanolamine. Findings. A new matrix of composite absorbents based on nitrogen-containing water-soluble polyelectrolytes, methylethanolamine, diethanolamine and methyldiethanolamine has been obtained. [ABSTRACT FROM AUTHOR]

Supported polyethyleneimine (PEI) adsorbent is one of the most promising commercial direct air capture (DAC) adsorbents with a long research history since 2002. Although great efforts have been input, there are still limited improvements for this material in its CO2 capacity and adsorption kinetics under ultradilute conditions. Supported PEI also suffers significantly reduced adsorption capacities when working at sub‐ambient temperatures. This study reports that mixing diethanolamine (DEA) into supported PEI can increase 46% and 176% of pseudoequilibrium CO2 capacities at DAC conditions compared to the supported PEI and DEA, respectively. The mixed DEA/PEI functionalized adsorbents maintain the adsorption capacity at sub‐ambient temperatures of −5 to 25 °C. In comparison, a 55% reduction of CO2 capacity is observed for supported PEI when the operating temperature decreases from 25 to −5 °C. In addition, the supported mixed DEA/PEI with a ratio of 1:1 also shows fast desorption kinetics at temperatures as low as 70 °C, resulting in maintaining high thermal and chemical stability over 50 DAC cycles with a high average CO2 working capacity of 1.29 mmol g−1. These findings suggest that the concept of "mixed amine", widely studied in the solvent system, is also practical to supported amine for DAC applications. [ABSTRACT FROM AUTHOR]

This work is aimed to develop several cationic amphiphiles based on amino acid derivatives of diethanolamine as potentially membrane-active antibacterial agents. The developed compounds contain two amino acid residues in the polar block and aliphatic chains of various length in the hydrophobic domain. Amphiphiles were obtained in preparative amounts sufficient to confirm their structures and perform a study of antibacterial activity. The synthesized samples based on β-Ala (4c) and GABA (4d) with aliphatic C12 chain in the hydrophobic domain showed a promising level of antimicrobial activity against gram-positive (B. subtilis) and gram-negative (E. coli) bacteria (minimal inhibitory concentration, MIC, 1 μg/mL). Amphiphiles containing aromatic amino acids L-Phe (6a) and L-Trp (6b) in the polar head group and C8 hydrocarbon chain exhibited an antibacterial activity against B. subtilis with MIC of 1 μg/mL. The obtained data on antimicrobial activity make the selected compounds attractive for further detailed study of their mechanism of action. [ABSTRACT FROM AUTHOR]

Objectives Acid gases such as carbon dioxide (CO2) and hydrogen sulfide (H2S) that cause global warming are mainly generated in chemical processes. As a technology for reducing acid gas, the post-combustion capture process is representative. Aqueous alkanolamine solution, which is mainly used in the carbon dioxide absorption process, is used as the most representative chemical absorbent. Thermodynamic data of vapor-liquid equilibrium are important for the economics of process design and operation. In this study, vapor-liquid equilibrium data of water + DEA are measured so that DEA, a secondary amine, can be used in the carbon dioxide absorption process, so that it can be used for designing a new carbon dioxide absorption process. Methods Vapor-liquid equilibrium data of a mixture of water + DEA (diethanolamine) were measured under isothermal conditions of 393.15 K using HSGC (Headspace Gas Chromatography). Results and Discussion The measured vapor-liquid equilibrium data were correlated using NRTL, an activity coefficient model. In addition, as additional thermodynamic data of the absorbent mixture, the density of the DEA aqueous mixture was measured at a temperature of 303.15 K to 333.15 K using a density meter (Anton Paar DMA4500). The measured density data of the mixture was converted into excess volume, and the excess volume data was correlated using the Redilchi-Kister-Muggianu equation. Using the measured water+DEA vapor-liquid equilibrium data, it is expected to reducing the design cost and operating cost of the carbon dioxide absorption processes.

Carbon dioxide (CO2) is an acidic and corrosive gas, and the presence of this gas in the piping system can cause various problems in the industrial sector. Therefore, the CO2 must be separated from the gas stream. One of the CO2 gas separation processes from the gas stream is carried out in a CO2 removal unit, where a desorption unit serves as a solvent regeneration step. Therefore, this study aims to develop a rate-based model and simulation of the reactive desorption process of CO2 gas in a sieve tray column. The rate-based model in the reactive desorption process of CO2 gas is based on film theory, the liquid in the tray is assumed completely agitated due to gas bubbling, the flow pattern of gas is plug flow, and the effect of the reaction on the mass transfer follows the enhancement factor concept. The number of trays used in this study was 20. In addition, the effect of several variables, such as: desorber pressure, rich amine temperature, rich amine flow rate, and reboiler load, was also assessed on the CO2 stripping efficiency. The accuracy of our prediction model is 1.34% compared with industrial plant data. Compared with the chemical engineering simulator simulation results, the average deviation is 4%. Copyright © 2022 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

The present study aimed to investigate the feasibility of blended amine absorbents in improving the CO2 alkanolamine-based absorption of multicycle integrated absorption–mineralization (multicycle IAM) under standard operating conditions (20–25 °C and 1 atm). Multicycle IAM is a promising approach that transforms CO2 emissions into valuable products such as carbonates using amine solvents and waste brine. Previously, the use of monoethanolamine (MEA) as an absorbent had limitations in terms of CO2 conversion and absorbent degradation, which led to the exploration of blended alkanolamine absorbents, such as diethanolamine, triethanolamine, and aminomethyl propanol (AMP) combined with MEA. The blended absorbent was evaluated in terms of the absorption performance and carbonate production in continuous cycles of absorption, precipitation/regeneration, and preparation. The results showed that the fourth cycle of the blend of 15 wt.% AMP and 5 wt.% MEA achieved high CO2 absorption and conversion efficiency, with approximately 87% of the absorbed CO2 being converted into precipitated carbonates in 43 min and a slight degradation efficiency of approximately 45%. This blended absorbent can improve the efficiency of capturing and converting CO2 when compared to the use of a single MEA, which is one of the alternative options for the development of CO2 capture and utilization in the future. [ABSTRACT FROM AUTHOR]

In this paper, the concentration functions of electrical conductivity and pH are determined for aqueous solutions of an ionic liquid based on diethanolamine and boric acid (DEAB). Correlations between the physicochemical properties of an aqueous solution of DEAB and the processes of dissociation of the system components were established. Charge carriers in DEAB solutions are shown to be anions. It was established that an aqueous solution of DEAB has unipolar electrical conductivity and anion-exchange properties with an anion transfer number of 0.79. [ABSTRACT FROM AUTHOR]

In this contribution, the mechanism of carbonyl sulfide (COS) absorption by N‐methyldiethanolamine (MDEA) aqueous solution was explored via theoretical computations. Detailed reaction mechanisms were analyzed using density functional theory (DFT) calculations at the B3LYP‐D3 level of theory. In total, four different pathways for COS absorption by MDEA have been considered. The most favorable pathway for the removal of COS is a three‐step mechanism including the hydrolysis, proton transfer, and dissociation of CO2, and hydrolysis is the rate‐determining step. The mechanisms of the COS absorption by different amines were investigated, and the calculated results suggest that the total energy barrier for the COS absorption by MDEA is comparable to that by monoethanolamine (MEA), diethanolamine (DEA), and diisopropylamine (DIPA), indicating the COS absorption by all the four amines are feasible, while MDEA gives a better performance in terms of thermodynamics. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Supported polyethyleneimine (PEI) adsorbent is one of the most promising commercial direct air capture (DAC) adsorbents with a long research history since 2002. Although great efforts have been input, there are still limited improvements for this material in its CO2 capacity and adsorption kinetics under ultradilute conditions. Supported PEI also suffers significantly reduced adsorption capacities when working at sub‐ambient temperatures. This study reports that mixing diethanolamine (DEA) into supported PEI can increase 46% and 176% of pseudoequilibrium CO2 capacities at DAC conditions compared to the supported PEI and DEA, respectively. The mixed DEA/PEI functionalized adsorbents maintain the adsorption capacity at sub‐ambient temperatures of −5 to 25 °C. In comparison, a 55% reduction of CO2 capacity is observed for supported PEI when the operating temperature decreases from 25 to −5 °C. In addition, the supported mixed DEA/PEI with a ratio of 1:1 also shows fast desorption kinetics at temperatures as low as 70 °C, resulting in maintaining high thermal and chemical stability over 50 DAC cycles with a high average CO2 working capacity of 1.29 mmol g−1. These findings suggest that the concept of “mixed amine”, widely studied in the solvent system, is also practical to supported amine for DAC applications.

The reaction of carbon dioxide (CO2) with aqueous 2,2′-iminodiethanol (trivial name is diethanolamine: DEA) has been investigated using both blue moon ensemble and metadynamics approaches combined with ab initio molecular dynamics (AIMD) simulations. A spontaneous direct proton transfer from DEA zwitterion (DEAZW) to DEA but not to H2O has been observed in straightforward AIMD simulation in the time scale of ps. The ab initio free-energy calculations reproduced the overall free-energy difference, predicting the ionic products DEA carbamate ion (DEAC) and the protonated DEA (DEAH). The computed free-energy barrier for the first reaction step, which is the CO2 binding (48 kJ mol−1), is found to agree reasonably well with the available experimental data (52–56 kJ mol−1). By contrast, the barriers for the next step, the deprotonation of zwitterion realized either via reaction with DEA or H2O, are underestimated by 25–35 kJ mol−1 compared to the experimental reference. A part of this error is attributed to the neglected reversible work needed to bring two reactants together, which might significantly contribute to the free-energy of activation of bimolecular reactions in a dilute solution. The computed free-energy profile is compared with our results [Y. Kubota et al., J. Chem. Phys. 146, 094303 (2017)] for the same reaction in 2-aminoethanol (trivial name is monoethanolamine: MEA). [ABSTRACT FROM AUTHOR]

Abstract In this study, a strong anionic resin was used to remove the chloride ion in the diethanolamine of sweetening unit of gas refinery. A laboratory pilot has been investigated as a resin-filled bed to evaluate the reaction temperature, chloride ion concentration, resin saturation, resin recovery rate, optimal reaction temperature, diethanolamine flow rate, hydrogen strength and resin performance in this work. The resin saturation time, capacity of resin, optimal reaction temperature and changes in chloride concentration of the output stream from resin were determined in this research. Finally, the optimal amount of water to regulate the pH of the resin and the optimal amount of 4% sodium hydroxide solution to recycle the resin were calculated. It was found that one liter of resin is able to absorb 20.77 g of chloride. The temperature of 50 °C was considered as the optimal temperature of ion exchange reaction by comparing the amount of caustic and water consumption for resin recovery and regulation of neutral acidity, respectively. In this study, the amount of 4 wt.% caustic and water at a temperature of 50 °C for recovery of 134 g of resin obtained was equal to 8.5 and 5 L, respectively.

Abstract Numerous autism spectrum disorder (ASD) risk genes are associated with Wnt signaling, suggesting that brain development may be especially sensitive to genetic perturbation of this pathway. Additionally, valproic acid, which modulates Wnt signaling, increases risk for ASD when taken during pregnancy. We previously found that an autism‐linked gain‐of‐function UBE3AT485A mutant construct hyperactivated canonical Wnt signaling, providing a genetic means to elevate Wnt signaling above baseline levels. To identify environmental use chemicals that enhance or suppress Wnt signaling, we screened the ToxCast Phase I and II libraries in cells expressing this autism‐linked UBE3AT485A gain‐of‐function mutant construct. Using structural comparisons, we identify classes of chemicals that stimulated Wnt signaling, including ethanolamines, as well as chemicals that inhibited Wnt signaling, such as agricultural pesticides, and synthetic hormone analogs. To prioritize chemicals for follow‐up, we leveraged predicted human exposure data, and identified diethanolamine (DEA) as a chemical that stimulates Wnt signaling in UBE3AT485A–transfected cells, and has a high potential for prenatal exposure in humans. DEA enhanced proliferation in primary human neural progenitor cell lines (phNPC), but did not affect expression of canonical Wnt target genes in NPCs or primary mouse neuron cultures. Instead, we found DEA increased expression of the H3K9 methylation sensitive gene CALB1, consistent with competitive inhibition of the methyl donor enzymatic pathways.

A unique class of β-boron-functionalized non-steroidal anti-inflammatory compound (pinB-NSAID) was previously synthesized via copper-catalyzed 1,2-difunctionalization of the respective vinyl arene with CO2 and B2pin2 reagents. Here, pinacolylboron-functionalized ibuprofen (pinB-ibuprofen) was used as a model substrate to develop the conditions for pinacol deprotection and subsequent boron functionalization. Initial pinacol-boronic ester deprotection was achieved by transesterification with diethanolamine (DEA) from the boralactonate organic salt. The resulting DEA boronate adopts a spirocyclic boralactonate structure rather than a diazaborocane–DABO boronate structure. The subsequent acid-mediated hydrolysis of DEA and transesterification/transamination provided a diverse scope of new boron-containing ibuprofen derivatives. [ABSTRACT FROM AUTHOR]

Copyright of New Building Materials / Xinxing Jianzhu Cailiao is the property of New Building Materials Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Simplifying device layout, particularly avoiding the complex fabrication steps and multiple high-temperature treatment requirements for electron-selective layers (ESLs) have made ESL-free perovskite solar cells (PSCs) attractive. However, the poor perovskite/substrate interface and inadequate quality of solution-processed perovskite thin films induce inefficient interfacial-charge extraction, limiting the power conversion efficiency (PCEs) of ESL-free PSCs. A highly compact and homogenous perovskite thin film with large grains was formed here by inserting an interfacial monolayer of diethanolamine (DEA) molecules between the perovskite and ITO substrate. In addition, the DEA created a favorable dipole layer at the interface of perovskite and ITO substrate by molecular adsorption, which suppressed charge recombination. Comparatively, PSCs based on DEA-treated ITO substrates delivered PCEs of up to 20.77%, one of the highest among ESL-free PSCs. Additionally, this technique successfully elongates the lifespan of ESL-free PSCs as 80% of the initial PCE was maintained after 550 h under AM 1.5 G irradiation at ambient temperature. [ABSTRACT FROM AUTHOR]

A novel combinatorial approach including computer-aided simulation and robust statistical data-based methods was introduced to intensify the chemical absorption process of H 2 S by diethanolamine (DEA) from sour industrial off-gas. Effects of three parameters (lean amine H 2 S impurity (LAHI), lean amine temperature (LAT) and column pressure (CP) on the alteration trends and sensitivity of H 2 S removal were studied using response surface methodology (RSM) and Sobol's sensitivity analysis (SA). Then, the optimal conditions for maximizing the H 2 S removal were determined. Results depicted that H 2 S removal will be decreased at higher LAHI and LAT. SA showed that LAHI (83%) was the most impactful factor on H 2 S removal. LAT (15%) and CP (2%) showed a relatively-low and negligible effects on the removal efficiency, respectively. It was shown that low impact of LAT and CP on H 2 S removal arised from weak variations of thermodynamic parameters of H 2 S absorption (H 2 S solubility, equilibrium constant, and enthalpy of absorption) with those factors. Maximum H 2 S removal of 99.995% was resulted at the optimal values of LAHI = 0.01 mol H2S /mol DEA , LAT = 53.7 °C, and CP = 1500 kPa. [Display omitted] • H 2 S absorption by diethanolamine (DEA) was studied in industrial scale. • Effects of H 2 S loading, lean amine temperature and column pressure on H 2 S removal were examined. • Sensitivity analysis disclosed the strongest impact of H 2 S loading on removal efficiency. • Column pressure has a negligible impact on H 2 S removal. • Process optimization for the maximization of removal efficiency was done. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) is an acidic and corrosive gas, and the presence of this gas in the piping system can cause various problems in the industrial sector. Therefore, the CO2 must be separated from the gas stream. One of the CO2 gas separation processes from the gas stream is carried out in a CO2 removal unit, where a desorption unit serves as a solvent regeneration step. Therefore, this study aims to develop a rate-based model and simulation of the reactive desorption process of CO2 gas in a sieve tray column. The rate-based model in the reactive desorption process of CO2 gas is based on film theory, the liquid in the tray is assumed completely agitated due to gas bubbling, the flow pattern of gas is plug flow, and the effect of the reaction on the mass transfer follows the enhancement factor concept. The number of trays used in this study was 20. In addition, the effect of several variables, such as: desorber pressure, rich amine temperature, rich amine flow rate, and reboiler load, was also assessed on the CO2 stripping efficiency. The accuracy of our prediction model is 1.34% compared with industrial plant data. Compared with the chemical engineering simulator simulation results, the average deviation is 4%. [ABSTRACT FROM AUTHOR]

Diethanolamine, monoethanolamine, iminodiacetic acid, and glycine are important fine chemical intermediates, often requiring simultaneous quantitative analysis in various applications. This presents the challenge of accurately quantifying multiple substances within a single sample. The catalytic dehydrogenation of diethanolamine and monoethanolamine has garnered significant research interest, yet no analytical method has been reported for the simultaneous quantification of reactants and products in the dehydrogenation reaction mixtures of different alkanolamines. A high-performance liquid chromatography (HPLC) method has been developed for the simultaneous quantification of diethanolamine (DEA), iminodiacetic acid (IDA), glycine (Gly), and monoethanolamine (MEA) in aqueous solutions using 2,4-dinitrofluorobenzene (DNFB) for pre-column derivatization. The method demonstrated excellent linearity, with correlation coefficients (R2) of 0.9999, 0.9997, and 0.9998 for IDA, DEA, and Gly, respectively. The detection limits (LODs) were 0.02, 0.08, and 0.01 mg L−1, respectively. The quantification limits (LOQs) were 0.06, 0.24, and 0.03 mg L−1, respectively. Spiked recovery rates ranged from 96.99 % to 104.32 %, with relative standard deviations (RSDs) between 0.70 % and 3.03 %. For MEA and Gly, the R2 values were 0.9970 and 0.9990, the LODs were 0.12 and 0.01 mg L−1, the LOQs were 0.36 and 0.03 mg L−1, and spiked recoveries ranged from 96.24 % to 104.82 %, with RSDs between 1.22 % and 3.68 %. Compared to other methods, this HPLC approach offers superior sensitivity, accuracy, and precision. This method provides a robust reference for the individual or simultaneous quantification of alkanolamines, glycine, and iminodiacetic acid in aqueous matrices. It offers new insights into the simultaneous analysis of alkanolamines with multiple organic acids in complex matrices. Additionally, the method can guide the optimization of catalytic dehydrogenation processes for alkanolamines, potentially extending the advantages of dehydrogenation catalysts to other reactions. [Display omitted] • An HPLC analytical method using DNFB pre-column derivatization has been developed. • The problem of simultaneous quantification of diethanolamine, iminodiacetic acid, and glycine in aqueous matrices has been solved. • The problem of simultaneous quantification of monoethanolamine and glycine in aqueous matrices has been solved. • The challenge of simultaneously quantifying reactants and products in disparate alkanolamine-catalyzed dehydrogenation procedures has been overcome. [ABSTRACT FROM AUTHOR]

To improve the anticancer activity of commercial drugs, a series of well-defined Janus dendrimer conjugates with chlorambucil (CLB) and naproxen, which feature diethanolamine groups and ethylene glycol in the structure, were synthesized and characterized in detail. The anticancer activity of all synthesized dendrons and dendrimers were tested and screened against six human cancer cells. In vitro all conjugates at 25 μM exhibit selectivity towards human mammary adenocarcinoma (MFC-7) cells as compared to U-251, PC-3, and HCT-15 cells, while being only slightly active in SKLU-1 and K-562 cells. The IC 50 values showed that the best growth suppressor of MFC-7 (4 ± 0.3 μM) was the second-generation dendrimer with four chlorambucil and four naproxen moieties. The result indicates that Janus dendrimers are promising molecular scaffolds for the design of more potent anticancer drugs. Further biological evaluations, such as the anticancer activity of the Janus dendrimers in vivo , are ongoing. [Display omitted] [ABSTRACT FROM AUTHOR]

Refineries produce about four percent of the global carbon dioxide emissions, close to one billion tons per year. Globally, the refining sector is the third largest producer of carbon dioxide after the electricity generation and cement industry.This greenhouse gases is a major cause of global warming and climate change and is a serious threat to human health and the environment. One way to reduce this greenhouse gas into the atmosphere is to reduce carbon dioxide by reversing this gas in the fuel cycle.The Fluid Catalytic Cracking unit (FCCU) is one of the emissions sources of this greenhouse gas in Abadan Refinery,which produces 230 tons per hour of combustion gases,it has 12.7% mole of carbon dioxide. Identifying the sources of carbon dioxide emissions in Abadan Refinery and simulating the chemical absorption of this greenhouse gas and converting it into methanol fuel is one of the objectives of this study. Methods: In this research, the concentration of carbon dioxide emitted from the emission sources of Abadan Refinery has been measured by Testo 350-XL and GC. Due to the fact that the concentration of carbon dioxide in the combustion gases of the FCC unit was the highest amount, so the chemical absorption of carbon dioxide from the combustion gases of this unit by 30 wt% diethanolamine solvent and converted into methanol during a hydrogenation reaction has been simulated with Aspen Hysys software. Finally, the economic calculations of the project were performed. Results: The overall efficiency of chemical absorption of CO2 in the simulation with software is 92% and the purity of captured CO2 is 94.6%. With this method, 1003 ton per day of carbon dioxide in FCC unit can be absorbed and recovered and also converted into methanol product. In the simulation of the conversion of recovered carbon dioxide into methanol, the amount of 686 ton per day of methanol with a purity of 99.8% was obtained. The economic calculations of the project show that the cost of reducing emissions per ton of carbon dioxide is $ 19. The internal rate of return on the project is 22% and the net present value of the project is $ 92 million. The return time on investment of this project is 3 years. Conclusion: Diethanolamine has a high efficiency in absorbing carbon dioxide from combustion gases.By chemical absorption method with this amine, carbon dioxide pollutant can be recovered from combustion gases that produced in refineries and used as an inexpensive feed to produce methanol fuel.This method, in addition to creating added value, prevented the emission of this greenhouse gas into the environment.

8-Aryl-7H-acenaphtho[1,2-d] imidazoles were produced by a catalytic process utilizing diethanolamine sulfate-functionalized graphene oxide. The process was implemented using acenaphthoquinone, ammonium acetate, and aromatic aldehydes via a one-pot reaction under solvent-free conditions. The applied catalyst smoothly catalyzed the reactions at high yields. The developed catalyst offered several advantages including carbon structure, eco-friendliness, cost-effectiveness, and ease of handling and storage. The applied procedure also exhibited several priorities over reported ones such as high yield, short reaction time, no-byproducts, environmental compatibility, and simple work-up. Durability and stability of catalyst were also examined in five cycles which showed no significant reduction in the catalytic activity. [ABSTRACT FROM AUTHOR]

Integrated absorption–mineralization (IAM) involves the transformation of CO2 in a chemical-based solution with brine used as the absorbent to form insoluble carbonates and is promising for carbon capture, utilization, and storage. Various types of absorbents such as monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), and aminomethyl propanol (AMP) were examined in multicycle integrated absorption–mineralization (multicycle IAM) involving absorption, precipitation, and regeneration steps between 20 °C and 25 °C at atmospheric pressure in order to reveal their performance in terms of CO2 absorption and conversion and absorbent degradation. We found that 5 wt.% AMP offered 89.5% CO2 absorption capacity per unit of absorbent converted into the amount of solid carbonate within 4 cycles. In addition, it was moderately degraded by 64.02% during the first cycle and then reduced from 30% to 10% in the next cycle (>2 cycles). In comparison with MEA, which was used as the initial absorbent, AMP provided a fivefold increase in the speed of multicycle IAM. [ABSTRACT FROM AUTHOR]

Diethanolamine (DEA) is used for amine wash to remove toxic gases such as hydrogen sulphide (H2S) while processing crude oil and in other pharmaceutical products. The detection of diethanolamine is of prime importance to avoid its harmful impact. In this study, we have designed a lossy mode resonance (LMR)-based optical fiber sensor for the detection of DEA. An optical fiber probe was fabricated by coating a bulk layer of titanium dioxide (TiO2) on the core of the optical fiber (probe-1). To extend this study, we prepared biosynthesised gold nanoparticles and coated them on to the top of the TiO2-layer-coated probe (probe-2). The surface structure was confirmed using characterization techniques such as FESEM, HRTEM and UV-visible spectroscopy. Further, a comparative study among probe-1 and probe-2 has been carried out in terms of their performance parameters such as sensitivity, figure of merit, limit of detection, repeatability and response time. The sensitivity of the TiO2 bulk layer/AuNP bilayer-coated optical fiber probe (probe-2) was observed to be 16 079.63 nm RIU−1 (0.074 nm mM−1), which was approximately double the sensitivity of the TiO2 bulk layer-coated optical fiber probe (probe-1). Selectivity experiments were also performed to confirm the high sensitivity of the sensor towards DEA. [ABSTRACT FROM AUTHOR]

In this paper, we describe the synthesis of cationic amphiphiles based on aliphatic and aromatic amino acids and diethanolamine derivatives. The calculation of the hydrophilic-lipophilic balance for a number of structures makes it possible to identify the structures with potential antimicrobial activity against gram-positive and gram-negative bacterial strains. The schemes for the synthesis of mono/bivalent cationic lipoamino acids and lipopeptides are developed. Two series of amphiphiles are obtained in preparative quantities for subsequent microbiological studies and determining the minimum inhibitory concentration. [ABSTRACT FROM AUTHOR]

In this study, an industrial acid gas removal (AGR) process which uses amine-based solvents was designed and simulated. The selection of suitable absorbents is crucial for an effective AGR process. Therefore, various single and blended amine-based solvents for capturing acid gases were evaluated through a comprehensive procedure, including solvent screening and process design steps. First, various solvents were screened for their CO2 and H2S absorption efficiencies. Promising solvents were then selected for the process design step, in which all process alternatives were simulated and rigorously designed using Aspen Plus. The non-equilibrium rate-based method with an electrolyte non-random two-liquid thermodynamic model was employed for modeling the absorption column. All processes were evaluated in terms of energy requirements, costs, and carbon emissions. The results show that a blend of methyldiethanolamine and piperazine solutions are the most promising solvents for the AGR process, as they can save up to 29.1% and 30.3% of the total annual costs and carbon emissions, respectively, compared to the methyldiethanolamine + diethanolamine solvent process. [ABSTRACT FROM AUTHOR]

In this study, a strong anionic resin was used to remove the chloride ion in the diethanolamine of sweetening unit of gas refinery. A laboratory pilot has been investigated as a resin-filled bed to evaluate the reaction temperature, chloride ion concentration, resin saturation, resin recovery rate, optimal reaction temperature, diethanolamine flow rate, hydrogen strength and resin performance in this work. The resin saturation time, capacity of resin, optimal reaction temperature and changes in chloride concentration of the output stream from resin were determined in this research. Finally, the optimal amount of water to regulate the pH of the resin and the optimal amount of 4% sodium hydroxide solution to recycle the resin were calculated. It was found that one liter of resin is able to absorb 20.77 g of chloride. The temperature of 50 °C was considered as the optimal temperature of ion exchange reaction by comparing the amount of caustic and water consumption for resin recovery and regulation of neutral acidity, respectively. In this study, the amount of 4 wt.% caustic and water at a temperature of 50 °C for recovery of 134 g of resin obtained was equal to 8.5 and 5 L, respectively. [ABSTRACT FROM AUTHOR]