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Zhao Hua Ren – One of the best experts on this subject based on the ideXlab platform.
mechanism on micellization of amino sulfonate Amphoteric Surfactant in aqueous solutions containing different alcohols and its interfacial adsorptionJournal of Molecular Liquids, 2020Co-Authors: Jing Huang, Zhao Hua RenAbstract:
Abstract The process of micellization of Amphoteric Surfactant sodium 3-(N-dodecyl ethylenediamino)-2-hydroxypropyl sulfonate (C12AS) in aqueous solution without or with alcohols including methanol, ethanol, 1-propanol and 1-butanol and their adsorption behavior at air-liquid interface were investigated with both the tensiometry and the conductometry at 298.15 K. The effect of chain length of alcohol on micellar and interfacial properties were discussed. Some parameters including surface excess concentration (Γmax), minimum area per Surfactant molecule (Amin) at air-liquid interface, degree of ionization of micelle, Gordon parameters and cohesive energy density of pure or mixed solvent, and standard free energy of adsorption and micellization, etc. are estimated. At the same amount of alcohol in g/L, the addition of different alcohols changes the values of Γmax, Amin and critical micelle concentration (cmc) of C12AS. Also, the effect of alcohol was discussed. The obtained thermodynamic parameters were used to confirm these behaviors of interfacial adsorption or micellization. These behaviors can be explained theoretically by the change in the polarity or cohesive energy of pure or mixed solvents, the surface charge density of micelle, the partition coefficient of alcohol between micellar pseudophase and intermicellar phase, and the conformation of head group of C12AS on adding alcohol. These findings help with understanding self-assembly behavior of C12AS molecule having electronic delocalization structure at air-liquid interface or in bulk phase and the effect of additives on them, and these results can also provide some information for the design of Surfactant formulations and their application in many fields.
a molecular thermodynamic approach to predict the micellization of binary Surfactant mixtures containing amino sulfonate Amphoteric Surfactant and nonionic SurfactantAiche Journal, 2017Co-Authors: Zhao Hua RenAbstract:
A molecular-thermodynamic approach was adopted to predict the value of mixed critical micelle concentration (cmc) for the binary Surfactant mixtures constituted by an amino sulfonate Amphoteric Surfactant, sodium 3-(N-dodecyl ethylenediamino)-2-hydropropyl sulfonate (abbr. C12AS), and a nonionic Surfactant, octylphenol polyethylene ether (OP-n, where n denotes the average number of oxyethylene glycol ether). In this investigation, considering two positive charges on the hydrophilic group of C12AS, which is unlike to conventional zwitterionic Surfactants having one positive charge (such as, alkylbetaine, etc.), three schemes were designed to obtain the geometric parameter describing the dipole structure of C12AS. According to the selected optimum scheme, four cases corresponding to the different conformations of both the headgroup and the hydrocarbon chain of Surfactant were discussed. The results show that the predicted value of mixed cmc for the C12AS/OP-n mixtures agrees well with the experiment value. The deviation of the predicted value from the experimental value can be explained by the effect of the hydrophilicity of OP-n on the process of micellization. This article is protected by copyright. All rights reserved.
effect of isopropanol on the micellization of binary mixture containing amino sulfonate Amphoteric Surfactant in aqueous solution mixing with octylphenol polyoxyethylene ether 7Journal of Molecular Liquids, 2017Co-Authors: Zhao Hua Ren, Jing Huang, Yan Cheng Zheng, Lu LaiAbstract:
Abstract A systematic investigation of the effect of isopropanol (IPA) on the micellization of binary mixtures of an Amphoteric Surfactant, sodium 3-( N -dodecyl ethylenediamino)-2-hydroxypropyl sulfonate (C12AS), with a nonionic Surfactant, octylphenol polyoxyethylene ether having seven oxyethylene glycol ether (OP-7), the interaction between them, and thermodynamic parameters was performed in the water-IPA mixed solvent media (the concentration of IPA in bulk solution is within the range of 0 to 100 g/L) at 25 ± 0.2 °C. The values of critical micelle concentration ( cmc ) of individual Surfactants and their mixtures were determined by both the tensiometry and the UV–vis spectrometry. According to the pseudophase separation and other theromdynamic models (including Clint’s model, Rubingh’s model, Maeda’s model, etc.), molar fractions of components and activity coefficients in mixed micelle, interaction parameters between two Surfactants, and thermodynamic parameters were calculated from the corresponding relationships. The variation of the cmc and the micellization parameters with the concentration of IPA can be explained by the structure-breaking ability of IPA and the change in the conformation of C12AS. The synergistic effect between two Surfactants can be observed and has a strong dependence on the concentration of IPA. Thermodynamic data show that the micellization for the C12AS/OP-7 mixture is a entropy-driven spontaneous process. The addition of IPA is a disadvantage to the formation of mixed micelle. In comparison with the case in aqueous solution without IPA, the presence of IPA causes a remarkable contribution of entropy to the process of micellization and the contribution increases with the concentration of IPA.
Xueqing Qiu – One of the best experts on this subject based on the ideXlab platform.
enhancement and mechanism of a lignin Amphoteric Surfactant on the production of cellulosic ethanol from a high solid corncob residueJournal of Agricultural and Food Chemistry, 2019Co-Authors: Hongming Lou, Cheng Cai, Yuxia Pang, Tianqing Lan, Haifeng Zhou, Xueqing QiuAbstract:
A lignin Amphoteric Surfactant and betaine could enhance the enzymatic hydrolysis of lignocellulose and recover cellulase. The effects of lignosulfonate quaternary ammonium salt (SLQA) and dodecyl dimethyl betaine (BS12) on enzymatic hydrolysis digestibility, ethanol yield, yeast cell viability, and other properties of high-solid enzymatic hydrolysis and fermentation of a corncob residue were studied in this research. The results suggested that SLQA and 1 g/L BS12 effectively improved the ethanol yield through enhancing enzymatic hydrolysis. SLQA had no significant effect on the yeast cell membrane and glucose fermentation. However, 5 g/L BS12 reduced the ethanol yield as a result of the fact that 5 g/L BS12 damaged the yeast cell membrane and inhibited the conversion of glucose to ethanol. Our research also suggested that 1 g/L BS12 enhanced the ethanol yield of corncob residue fermentation, which was attributed to the fact that lignin in the corncob adsorbed BS12 and decreased its concentration in solution to a safe level for the yeast.
Enhancement and Mechanism of a Lignin Amphoteric Surfactant
on the Production of Cellulosic Ethanol from a High-Solid Corncob
Residue, 2019Co-Authors: Hongming Lou, Cheng Cai, Yuxia Pang, Tianqing Lan, Haifeng Zhou, Xueqing QiuAbstract:
A lignin Amphoteric Surfactant and
betaine could enhance the enzymatic
hydrolysis of lignocellulose and recover cellulase. The effects of
lignosulfonate quaternary ammonium salt (SLQA) and dodecyl dimethyl
betaine (BS12) on enzymatic hydrolysis digestibility, ethanol yield,
yeast cell viability, and other properties of high-solid enzymatic
hydrolysis and fermentation of a corncob residue were studied in this
research. The results suggested that SLQA and 1 g/L BS12 effectively
improved the ethanol yield through enhancing enzymatic hydrolysis.
SLQA had no significant effect on the yeast cell membrane and glucose
fermentation. However, 5 g/L BS12 reduced the ethanol yield as a result
of the fact that 5 g/L BS12 damaged the yeast cell membrane and inhibited
the conversion of glucose to ethanol. Our research also suggested
that 1 g/L BS12 enhanced the ethanol yield of corncob residue fermentation,
which was attributed to the fact that lignin in the corncob adsorbed
BS12 and decreased its concentration in solution to a safe level for
using recyclable ph responsive lignin Amphoteric Surfactant to enhance the enzymatic hydrolysis of lignocellulosesGreen Chemistry, 2017Co-Authors: Cheng Cai, Xuejuan Zhan, Meijun Zeng, Hongming Lou, Yuxia Pang, Jia Yang, Dongjie Yang, Xueqing QiuAbstract:
In order to enhance the enzymatic hydrolysis of lignocelluloses and recycle Surfactants after enzymatic hydrolysis, a pH-responsive lignin Amphoteric Surfactant (SLQA) was prepared by the quaternization of sulfonated lignin (SL). Compared with SL, SLQA could much more effectively enhance the enzymatic hydrolysis of lignocelluloses. With an increase in the quaternization degree, enhancement of the enzymatic hydrolysis of lignocelluloses by the SLQA gradually increased. Adding 2 g L−1 SLQA-80 (mass radio of quaternizing agent to SL was 80%) could increase the enzymatic digestibility of pretreated eucalyptus and corncob residues (CCR) from 36.7% and 37.8% to 84.3% and 90.5%, respectively. The adsorption of SLQA on lignin film was larger than that of SL, and the lignin film became more hydrophilic after adsorbing SLQA. Thus, SLQA could cause more effective steric hindrance and form a hydration layer to reduce the non-productive adsorption of cellulase on lignin. The purified SLQA-80 exhibited sensitive pH-responsive property, and 90.8% of SLQA-80 could be recycled by adjusting the pH of hydrolysate after enzymatic hydrolysis. Adding recyclable SLQA could not only obviously enhance the enzymatic hydrolysis of lignocelluloses, but could also enable the comprehensive utilization of lignocelluloses. This method is of great significance to reducing the cost of cellulosic ethanol.
Naoto Koshizaki – One of the best experts on this subject based on the ideXlab platform.
Photoluminescence of ZnO Nanoparticles Prepared by Laser Ablation in Different Surfactant SolutionsThe Journal of Physical Chemistry B, 2005Co-Authors: Hiroyuki Usui, Yoshiki Shimizu, Takeshi Sasaki, Naoto KoshizakiAbstract:
ZnO nanoparticles were prepared by laser ablation of a zinc metal plate in a liquid environment using different Surfactant (cationic, anionic, Amphoteric, and nonionic) solutions. The nanoparticles were obtained in deionized water and in all Surfactant solutions except the anionic Surfactant solution. The average particle size and the standard deviation of particle size decreased with increasing Amphoteric and nonionic Surfactant concentrations. With the increase of the Amphoteric Surfactant concentration, the intensity of the defect emission caused by oxygen vacancies of ZnO rapidly decreased, while the exciton emission intensity increased. This indicates that anionic oxygen in the Amphoteric Surfactant molecules effectively occupied the oxygen vacancy sites at the ZnO nanoparticle surface due to charge matching with the positively charged ZnO nanoparticles.