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The aim of this systematic review was to evaluate the risk factors for cage subsidence (CS) after oblique lumbar interbody fusion (OLIF). The cohort and case-control studies which reporting potential risk factors for CS following OLIF were searched in PubMed, Embase, and Web of Science from database inception to June 17, 2023. Two researchers independently screened the literature, extracted data, and evaluated the quality of the literature according to the Newcastle Ottawa Scale. RevMan5.3 software was used for Meta analysis. χ2 statistics and I 2 statistics were used to evaluate heterogeneity, and the analysis results were represented by forest plots. A total of 8 studies with 280 cases of CS from 832 patients who underwent OLIF met the inclusion criteria. Elderly patients over 60 years old (odds ratio [OR] 2.44, 95% CI 1.38–4.31, P = 0.002), osteoporosis (OR 4.18, 95% CI 2.30–7.61, P = 0.002), end plate injury (OR 5.72, 95% CI 2.32–14.11, P = 0.0002), and overdistraction of intervertebral space (OR 1.67, 95% CI 1.3 2–2.11, P < 0.0001) were potential risk factors, while Hounsfield units value of the vertebral body (OR 0.97, 95% CI 0.95–1.00, P = 0.02) is a protective factor. The number of operative segments did not increase the risk of CS. Older age, osteoporosis, endplate injury, and overdistraction of the intervertebral space may increase the risk of CS after OLIF. Although the incidence rate of CS is low, implementing effective preventions is a priority for clinicians based on these risk factors. [ABSTRACT FROM AUTHOR]

Water-lean amine absorbents have potential in reducing regeneration energy consumption for post-combustion CO 2 capture. In this work, dimethyl sulfoxide (DMSO) was proposed as a cosolvent to develop water-lean monophasic absorbents for capturing CO 2 in the simulated flue gas treatment. CO 2 absorption and desorption performance has been investigated for nonaqueous/water-lean systems involving three secondary alkanolamines and compared with the conventional monoethanolamine (MEA). Effect of water content in these absorbents on reaction products, regeneration energy consumption and capture performance was also discussed. Interestingly, the DMSO-based amine blends can maintain the monophasic state before and after CO 2 absorption at the investigated conditions. Water-lean absorbent of 2-(butylamino)ethanol (BAE)/DMSO/H 2 O was proposed for energy-efficient CO 2 capture, due to the observed high cyclic capacity and super-low energy consumption. Increasing water content in the absorbents can slightly improve the absorption capacity and cyclic capacity, but significantly increased the regeneration energy. Maintaining the water content not higher than 10 mass% can reduce the regeneration energy by 48–55% compared with the benchmark aqueous 30% MEA (4.05 MJ kg−1 CO 2), which makes the proposed absorbent as a compelling candidate in the conventional CO 2 capture process without major process modification. [Display omitted] • The predicted and observed phase behaviors of amine/DMSO/Water matched well each other. • BAE/DMSO absorbents showed monophasic state during CO 2 absorption. • Nonaqueous DMSO-based system presented super-low regeneration energy consumption. • Increasing water content can both increase capture capacity and the regeneration heat duty. • BAE-DMSO-10%H 2 O can reduce energy consumption by about 45% than aqueous 30% MEA. [ABSTRACT FROM AUTHOR]

The solubility of CO 2 in aqueous potassium lysinate (LysK) solutions was measured in a stirred reactor at temperatures from 298 to 353 K, for 9.0, 17.4, 25.3, 33.1 and 41.2 mass% LysK and CO 2 partial pressures up to 110 kPa. The vapor-liquid equilibrium (VLE) data were interpreted using the modified Kent-Eisenberg model. The apparent equilibrium constants of carbamate hydrolysis and amino acid deprotonation were correlated as a function of temperature, CO 2 loading (expressed as mole CO 2 per mole LysK) and LysK concentration to fit the experimental solubility data. The proposed model satisfactorily predicted the VLE data for the H 2 O-LysK-CO 2 system, especially at moderate to high CO 2 loading, with an average absolute deviation within 3.2%. Liquid species in the CO 2 -loaded LysK solutions were also qualitatively characterized by 13 C NMR experiments. [ABSTRACT FROM AUTHOR]

In this work, CO 2 solubility in aqueous potassium lysinate solutions has been measured for the concentrations of (1.25–3.28) mol·kg −1 and at temperatures of (313–343) K. The vapour-liquid equilibrium data were correlated using a Soft model and a semi-empirical (SE) model. The proposed models can match well with the experimental data with AAD within 20%. The heat of absorption for LysK was estimated as about (55–70) kJ·mol −1 CO 2 absorbed from the solubility data. The lower heat of absorption, compared with that of 30 mass% MEA, will be beneficial for the reduction of regeneration energy. [ABSTRACT FROM AUTHOR]

[Display omitted] • Solvent-dependent phase transition behaviors for alkanolamine-glycol ether system. • A novel SPID method was proposed to predict the monophasic and the biphasic state. • Phase type I and II systems exhibited different CO 2 capture performance. • 50–60% reduction in regeneration energy consumption for nonaqueous MAE-based absorbents. Nonaqueous amine-based absorbents, particularly liquid biphasic solvents, have recently received increasing attention due to the potential for reducing the energy penalty of CO 2 capture. In this work, a series of glycol ethers were used as cosolvents dissolving primary and secondary alkanolamines. Phase transition behavior, CO 2 absorption and desorption characteristics have been investigated for the nonaqueous 5.0 M amine blends. Different phase behaviors upon CO 2 absorption were discussed and well explained by the polarity change and the solubility parameter interaction distance (SPID) of components and the reaction products. Regeneration energy requirement was also experimentally estimated and compared with the reference aqueous monoethanolamine (MEA). The species in the CO 2 -loaded solution play a central role in regulating phase separation behaviour and CO 2 capture performance. A defined SPID value was recommended to predict the monophasic and the biphasic states. Advanced systems of 2-(methylamino)ethanol (MAE) with diethylene glycol dimethyl ether (DEGDME) as liquid biphasic solvent and MAE with ethylene glycol monomethyl ether (EGME) as single phase solvent were proposed for energy-efficient CO 2 capture. Among the systems investigated, MAE/EGME has the lowest regeneration energy consumption estimated at about 1.75 MJ kg−1 CO 2 captured. The ionic carbonated products of alkanolamines can trigger the phase change behaviour due to their limited solubility in the more hydrophobic and weakly polar DEGDME, resulting in two opposite phases enriched in different components. Benefiting from the high enrichment (>95 %) of CO 2 captured in the lower phase and the large cyclic capacity, MAE/DEGDME biphasic solvent can reduce the energy consumption by 50–59 % compared with aqueous MEA. [ABSTRACT FROM AUTHOR]

Aqueous amino acid salts are attractive absorbents for carbon dioxide (CO 2 ) capture due to low volatility and resistance to oxidative degradation. The kinetics of CO 2 absorption into aqueous solutions of potassium histidinate (HisK) was investigated using a wetted wall column at concentrations ranging from 0.26 to 2.07 M and temperatures from 298 to 333 K. Density, viscosity of aqueous HisK and physical solubility of N 2 O in these solutions were measured. A temperature dependant ion parameter h His − was correlated to estimate Henry׳s constants of CO 2 . The zwitterion and termolecular mechanisms as well as ionic strength effect on reaction rate were applied to interpret the absorption rate of CO 2 in non-ideal systems. Under the pseudo-first-order regime, the overall reaction rate constants increase strongly with the increasing HisK concentration and temperature. HisK shows comparable chemical reactivity toward CO 2 with the industrial standard monoethanolamine (MEA). The partial reaction order with respect to HisK was found to be an average value of 1.26. Zwitterion deprotonation by water and HisK should be the rate-determining step. Two proposed models from zwitterion and termolecular mechanisms could successfully predict the experimental data within 12% AAD. The activation energy was calculated to be approximately 25.0 kJ mol −1 . [ABSTRACT FROM AUTHOR]

Amino acid salts have potential use as alternative absorbents to alkanolamines for post combustion CO 2 capture, because of their negligible volatility, resistance to oxidative degradation and fast absorption rates. In this work, the density and viscosity of CO 2 -free and CO 2 -loaded aqueous solutions of potassium lysinate (LysK) and potassium prolinate (ProK) were measured at temperatures from (298.15 to 348.15) K and for their concentrations from (0.2 to 3.0) mol L −1 . The data were correlated accurately ( R 2 ≥ 0.99) as a function of temperature, concentration and CO 2 loading by nonlinear regression analysis. The solubility of CO 2 in 2.5 mol L −1 amino acid salt solutions was also determined in vapor–liquid equilibrium vessels at temperatures (313 and 333) K and CO 2 partial pressures relevant to flue gas conditions. It was found that, the CO 2 absorption capacity of LysK is higher than that of industrially used monoethanolamine (MEA) and the CO 2 loadings vary as LysK > ProK > MEA at given CO 2 partial pressures. Moreover, LysK may offer higher cyclic loading than MEA for CO 2 capture. [ABSTRACT FROM AUTHOR]

Abstract: Carbonate-based solvents have advantages over amines for capturing CO2 from fossil fuel-fired power stations. However, due to slow reaction kinetics, boric acid has been proposed as rate promoter in carbonate-based solvents for reducing CO2 emission. In this work, borate promotion mechanism has been validated and vapor liquid equilibrium for 35wt% carbonate solutions with 1wt%, 3wt% boric acid was investigated at 323K, 333K and 343K. Based on complexation reaction with mannitol, results show that the tetrahydroxy borate ion, B(OH)4 −, is considered as a reactive specie toward carbon dioxide absorption. Effect of boric acid and temperature on equilibrium CO2 partial pressures was discussed in the investigated CO2 loading range. [Copyright &y& Elsevier]

• Henry's constants of N 2 O and CO 2 in MAE, 2-ME and their blends were measured. • VLE data of CO 2 + MAE + 2-ME system at various mass% MAE were determined. • A modified Kent-Eisenberg model can represent the VLE data with AARD of 12.6%. • K CO 2,app was well correlated as a function of temperature and carbonated degree of MAE. Nonaqueous secondary alkanolamine-based systems, replacing conventional water with 2-alkoxyethanols as cosolvents, have recently attracted much attention for an energy-efficient CO 2 capture process. In this work, physical solubility of N 2 O and CO 2 in 2-(methylamino)ethanol (MAE), 2-methoxyethanol (2-ME) and their blends was measured and correlated at temperatures ranging from (283.2 to 333.2) K. Vapor-liquid equilibrium (VLE) data for the CO 2 + MAE + 2-ME system at 7.8, 19.4 and 39.1 mass% MAE were also measured in a stirred equilibrium cell at temperatures of (313.2–393.2) K and CO 2 partial pressures up to 270 kPa. VLE data were represented by a modified Kent-Eisenberg model with an AARD of 12.6%. The apparent equilibrium constants considering the liquid nonideality were well correlated as a function of temperature, concentration of carbamate product and CO 2 loading. [ABSTRACT FROM AUTHOR]

Abstract: The absorption of carbon dioxide (CO2) into aqueous 35wt.% equivalent potassium carbonate (K2CO3) solution was performed using a wetted wall column at temperatures from 313K to 343K. Effect of arginine concentrations on absorption rates of CO2 into carbonate solutions was investigated and the second-order rate constant k 1 was obtained using two-film model. Preliminary screening results showed that arginine was an effective promoter in aqueous K2CO3 solution for CO2 capture. The reaction of CO2 with arginine is described using zwitterionic mechanism. The overall reaction kinetic constant k ov strongly increased with the increase of arginine concentration and absorption temperature under the investigated range. Based on the pseudo-first-order regime, the reaction rate parameters were obtained from the kinetic measurements and k 1 was determined as 33,641 and 85,367Lmol−1 s−1 at 315K and 325K, respectively with activation energy of 71.9kJmol−1. The overall reaction rate for CO2 absorption into promoted K2CO3 were described as the following equation: . [Copyright &y& Elsevier]

Abstract: Effluents from alkaloid processing plants could have adverse environmental effects. In this work, liquid–liquid extraction using trialkylphosphine oxide Cyanex 923 (TRPO) as an extractant has been proposed for alkaloid wastewater treatment. Partition behaviors of tyramine and morphine against pH were discussed and extraction equilibrium experiments were performed with various organic solvents at the optimal conditions. 50v/v% TRPO/kerosene was found as suitable solvent and showed good extraction performance due to hydrogen bond interaction and hydrophobic interaction with alkaloid compounds. Extraction mechanism and the complex species extracted were identified by slope analysis and FTIR spectra. Experimental overall mass transfer coefficients and recovery of tyramine were obtained under a range of hydrodynamic conditions in a handmade hollow fiber contactor. Model predictions based on a resistance in series model matched well with these experimental values for 50% TRPO/kerosene systems. Mass transfer resistances in this process were also analyzed. [Copyright &y& Elsevier]

Abstract: The removal of phenols from wastewater has been investigated under various operational conditions using hydrophobic hollow fiber membrane contactors. Experimental overall mass transfer coefficients were obtained in both handmade and Liqui-Cel modules. Model predictions based on a resistance in series model with solvent-filled membrane pores matched well with experimental values for tributyl phosphate/Shellsol extraction systems. However, the predictions were in poor agreement with experimental data obtained when 50% pentanol/xylene was used to treat industrial wastewater in the handmade module. Further analysis showed that the operational pressure on the aqueous side and the breakthrough pressure for the two solvents probably influenced the position of the interface within the membrane pores. This change in wetting patterns resulted in significant differences in mass transfer and solute recovery which can be accounted for by adjusting the position of the interface within the membrane fiber. [Copyright &y& Elsevier]

The effect of plate material on the dispersed-phase holdup in a Karr reciprocating plate column is studied. Existing models cannot predict the observed degradation of the performance of plates as they foul. Experimental data of dispersed-phase holdup have been obtained for a 10 vol% tributyl phosphate/kerosene-phenol-water system in a 50 mm Karr column under various operating conditions using stainless steel, Nylon, and Teflon plate materials. Characteristic velocities decreased with increasing agitation intensity for all systems studied. The characteristic velocities in the column with the Teflon plates were lower than with the other plate materials at the same operating conditions for aqueous-phase dispersion. The characteristic velocities in the column with stainless-steel plates were lower than with other plate materials for organic-phase dispersion. A comparison of the experimental holdups with predictions of existing models assesses the accuracy of the models. The effect of the wetting characteristics of the plate material, 1.406(1 + Cosθ)−0.1373, incorporated into a physical property parameter C ψ in the Kumar and Hartland model, gives a good fit for all the experimental data studied. [ABSTRACT FROM AUTHOR]

The accurate prediction of hollow-fiber membrane performance is limited by models of the shell-side mass-transfer coefficient. A review of the literature suggests that there have been in excess of 30 correlations for this coefficient. This article investigates these correlations in parallel-flow randomly-packed modules and cross-flow hollow-fiber membrane contactors. In particular, the variation of the Sherwood number on the shell side against the Reynolds number and packing density is considered. Shell-side mass-transfer performance is also investigated experimentally in a 10% (v/v) tributyl phosphate (TBP) in Shellsol2046/phenol/water system in four membrane modules. Data are compared with existing model predictions. The predicted values from four correlations agreed well with the observed data in randomly-packed hollow-fiber modules. In the commercial modules, experimental results varied greatly as a function of the Reynolds number. The use of a more consistent approach for the calculation of the linear fluid velocity on the shell side allowed the development of a generalized correlation, Shs = 0.055Re0.72 Sc0.33, (R2 = 0.77), that can predict the shell-side mass-transfer coefficient for both handmade and commercial membrane modules. [ABSTRACT FROM AUTHOR]

Abstract: Some stable three-liquid-phase extraction systems have been used for isolation and separation of glycyrrhizic acid (GA) and liquiritin (LQ) in aqueous Glycyrrhizia uralensis Fisch extract. Partition behaviors of two compounds were investigated at various conditions. Organic extractants and the pH of solution were two main factors to affect their partitioning among the phases and separation strategies. Different extraction profiles showed that the stronger the electron-donating capability of extractants, the higher the upper-limit of pH in the region for co-extracting GA and LQ, and the higher the lower-limit of pH in the region for stripping GA or LQ from the organic phase. Of all the investigated systems, the three-liquid-phase system containing poly(ethylene glycol-ran-propylene glycol) (EOPO2500) and tri-butyl phosphate (TBP) was the most suitable for separation and purification of licorice extract. FTIR and fluorescence spectroscopic investigations showed that hydrogen bond interaction and hydrophobic interaction among the phases were the main driving forces to affect the partition behaviors of two compounds. [Copyright &y& Elsevier]

Simultaneous quantitative determination of glycyrrhizic acid and liquiritin in Glycyrrhiza uralensis extract was developed using a high performance liquid chromatography (HPLC) coupled to an evaporative light scattering detector (ELSD). A Luna C18 column was used, along with a mobile phase consisting of acetonitrile and 3.0% (v/v) aqueous acetic acid in a gradient elution mode, at a flow rate of 1.0 mL/min. Parameters of ELSD were 105°C for the drift tube temperature and 2.8 L/min for the gas flow-rate. Retention times of liquiritin and glycyrrhizic acid were 4.1 and 8.3 min, respectively. Logarithmic calibration curves were obtained for glycyrrhizic acid from 0.50 to 5.72 μg (r² > 0.999) with a precision of 0.95% R.S.D and for liquiritin from 0.30 to 6.00 μg (r² > 0.999) with a precision of 0.59% R.S.D. The limit of quantitation (LOQ) of glycyrrhizic acid and liquiritin were 168.3 ng and 200 ng (S/N=3), respectively. This method was successfully applied to quality evaluation in licorice raw materials and related commercial formulations. [ABSTRACT FROM AUTHOR]

Abstract: Several new three-liquid-phase extraction systems containing ethylene oxide–propylene oxide (EOPO) random copolymers have been developed. These systems were used for treating simulated wastewater containing phenol and p-nitrophenol (p-NP). Effects of pH, phase-forming components and their concentrations on partition behaviors of phenolic compounds were investigated. Results showed that phenol and p-NP could be unevenly and efficiently partitioned among the phases at pH 9.3, with about 80% phenol in the top phase and 95% p-NP in middle phase, respectively. Separation factor of two compounds increased remarkably with the increase of pH from 4.0 to 10.0. The three-liquid-phase system containing poly(ethylene glycol-ran-propylene glycol) and butyl acetate (BA) was proved to be suitable for phenol and p-NP separation. The separation factor was over 13 at pH 8.43. [Copyright &y& Elsevier]

Abstract: A novel process for 6-aminnopenicillanic acid (6-APA) production from penicillin G fermentation broth was developed, which integrated some new technologies such as three-liquid-phase extraction and solvent sublation. A new three-liquid-phase extraction system containing ethylene oxide-propylene oxide (EOPO) random copolymer was used to separate and purify penicillin G from its filtrated broth and trace organic extractant in the aqueous phase of back-extraction was removed by solvent sublation. Experimental results showed that above 90% of penicillin G could be distributed into the upper organic phase at pH below 3.0, and most of impurities and some phenylacetic acids (PAA) were partitioned into the copolymer-rich middle phase. About 70% organic solvent could be stripped by one-step solvent sublation from penicillin G aqueous solution. The purity of 6-APA produced by the above-simplified process could be above 98% and other quality parameters reached the level of the conventional process. [Copyright &y& Elsevier]

• Solubility of N 2 O into EGME, EGEE and MEA-glycol ether solutions was measured. • Solubility of CO 2 in 5.0 M MEA-glycol ether solutions was obtained by the N 2 O analogy. • A mathematical model was proposed to interpret the VLE data of CO 2 -MEA-glycol ether systems. • The AADs are within 0.8% for Henry's constant and 10% for CO 2 solubility, respectively. Non-aqueous mixtures of monoethanolamine (MEA) with glycol ethers as low viscosity absorbents have potential advantages for CO 2 capture. In this work, physical solubility of N 2 O and CO 2 in glycol ethers (2-methoxyethanol and 2-ethoxyethanol) and their blends with MEA was measured and correlated at temperatures ranging from (293.15 to 333.15) K. Physical solubility of CO 2 in the blends was also estimated by N 2 O/CO 2 analogy method. A mathematic model based on the reaction mechanism was proposed to interpret the vapour-liquid equilibrium data for the systems of CO 2 /MEA/glycol ether solution. Results show that glycol ethers have greater ability to dissolve CO 2 than glycols and water. The apparent chemical equilibrium constant was obtained and correlated as a function of temperature by non-linear regression. The proposed model could reasonably fit the experimental data with an average absolute deviation within 10%. The heat of absorption of CO 2 in MEA/glycol ether systems was also calculated. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Reaction kinetics of CO 2 with ProK in ethanol solvent was measured in a stirred cell reactor. • Effect of polar solvents on the partial reaction order with regard to ProK was discussed. • The individual reaction rate constants in the ZM and TM models were correlated. Abstract Water-lean absorbents have potential applications for energy-efficient CO 2 capture. In this work, the chemical kinetics of the reaction between carbon dioxide (CO 2) and potassium prolinate (ProK) in ethanol, ethylene glycol and water solvents was measured in a stirred cell reactor with a stable gas-liquid interface at temperatures from 275.2 to 285.2 K and ProK molar concentrations up to 2.0 M. The experiments were performed under the pseudo-first-order regime to determine the overall kinetic rate constant (k ov) using two-film theory. The results showed that the reaction rates in each polar solvent increase considerably as the increasing ProK concentrations and temperatures. The reaction order was found to be in the range of 1.4–2.0 with respect to ProK concentration, depending on the solvents used. The kinetic results for the reaction in ethanol were also interpreted based on zwitterion mechanism and termolecular mechanism. The calculated from the two proposed models match well with the experimental data. [ABSTRACT FROM AUTHOR]

Highlights • Nonaqueous MEA + EGME mixtures have proposed as chemical absorbents for CO 2 capture. • Physical properties of CO 2 -free and CO 2 -loaded MEA + EGME systems were measured. • Experimental data were well correlated by the proposed models. • The AADs are within 4.5% for (ρ , η) and 19.5% for CO 2 solubility respectively. Abstract Non-aqueous amine-based absorbents are considered as a potential application for CO 2 removal from biogas to reduce energy consumption, due to lower heat capacity and evaporation enthalpy of organics than conventional water solvent. In this work, monoethanolamine (MEA) + 2-methoxyethanol (EGME) mixtures were proposed as a novel CO 2 carrier. The density and viscosity of CO 2 -free and CO 2 -loaded MEA + EGME solutions were measured at temperatures of (293–353) K, for 10–100 mass % MEA. CO 2 solubility in 31.0 mass% (5.0 M) MEA solutions was investigated at temperatures from 313 K to 393 K and CO 2 partial pressures up to 260 kPa. The excess molar volumes and the ratio of viscosity η · η EGME −1 were correlated by Redlich-Kister equation and Weiland's model, respectively. The vapour-liquid equilibrium data were correlated by using a semi-empirical model, i.e. CO 2 partial pressure as a function of temperature and CO 2 loading. The predicted values and the measured data matched well each other, with AAD within 0.2% for density, 4.5% for viscosity and 19.5% for CO 2 solubility respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • Water-lean EGHE-based CO 2 absorbents with novel water balance control was proposed. • Effect of water content on CO 2 capture performance of amine/EGHE/H 2 O was discussed. • EAE-EGHE-10%H 2 O showed about 40 % reduction in regeneration energy than aqueous MEA. Maintaining water balance in water-lean solvents is drawing special attention as it may affect the capture performance and process stability. In this study, novel water-lean solvents containing ethylene glycol monohexyl ether (EGHE) and secondary alkanolamines was proposed for energy-saving postcombustion CO 2 capture. Excess water from wet flue gas can be discharged from the desorber overhead condensate which can produce a spontaneous phase-separation feature. Less than 0.8 mass% EGHE was observed in the water-rich phase of the biphasic condensate. Effect of water content in these absorbents on CO 2 capture performance was discussed. Most notably, regeneration energy consumption increased significantly as increasing water content in the absorbent. The proposed water-lean absorbents with 10 % H 2 O can reduce the regeneration heat duty by about 40% in comparison with aqueous MEA, indicating that the novel water balance design can make it competitive in a practical sense. [ABSTRACT FROM AUTHOR]

[Display omitted] • Three types of phase transition behaviors for water-lean ProK-based CO 2 absorbents. • Water content plays a central role in regulating phase change behaviors. • L-L-S three phase absorbent shows great advantages over the reported biphasic system. • Phase change mechanisms were proposed based on composition analysis of each phase. • The underlying reason for excellent capture performance of the proposed system was unveiled. Water-lean phase change amino acid salts (AAS) are of great interest as potential absorbents for post-combustion CO 2 capture. In this work, effect of water content in the absorbent containing potassium prolinate (ProK) and 2-butoxyethanol (EGBE) on the phase behavior and capture performance was investigated to mimic water accumulation during wet flue gas treatment. Three types of phase separation behaviors were observed for the first time after CO 2 absorption from the homogenous liquid, as increasing water content in the absorbent. Phase change mechanisms were proposed based on composition analysis of each phase, which can well explain the improved regeneration efficiency by desorbing CO 2 -rich phases for the three-phase system. Noticeably, forming liquid–liquid-solid phase change for water-lean ProK/EGBE absorbent shows a promising strategy with advantages of high energy efficiency and water balance management for CO 2 capture. [ABSTRACT FROM AUTHOR]

The effects of the presence of a low-melting temperature inorganic salt (sodium sulfate) on the phase transformation, particle morphology and chroma of titanium dioxide white pigment were investigated. Powders were characterized by X-ray powder diffraction, scanning electronic microscopy, ultraviolet–visible–near infrared spectroscopy, infrared spectra and chroma measurements. For titanium dioxide pigments containing a lower salt content, the anatase–rutile phase transformation and crystal growth of titanium dioxide were inhibited. On the other hand, the anatase–rutile phase transformation and crystal growth of titanium dioxide was accelerated by the addition of higher salt concentrations. The chroma was observed to change with rutile content and morphology of the prepared samples. Here, the enhancement effects of salt doping on the phase transformation and crystal growth of titanium dioxide are understood via liquid-phase sintering processes. [ABSTRACT FROM AUTHOR]

The effect of gas compressibility on the fluid flow characteristics of a 350 MW air‐cooled turbo‐generator is investigated in this paper. Two gas models taking gas compressibility and incompressibility into account are established for numerical calculation. Then, a one‐fourth physical model based on the practical ventilation structure and basic assumption is built to analyse the flow velocity and flow rate using the finite volume method (FVM). The FVM‐predicted flow rate and flow velocity of cooling medium in the air cavity, stator and rotor of the generator show the distribution characteristics of flow rate and velocity in the generator is affected by the gas compressibility model selection. The comparison of FVM‐predicted flow rate and experimental value shows that the FVM‐predicted results using the gas compressibility model is more accurate when comparing to those using the incompressible model. Therefore, the gas compressibility model is an appealing approach to analyse the flow fluid characteristics of the air‐cooled turbo‐generator. [ABSTRACT FROM AUTHOR]

• Densities and viscosities of partially carbonated solutions of MAE + 2-alkoxyethanols were measured. • Dimensionless ρ loaded · ρ CO2-free −1 and η loaded · η CO2-free −1 were well represented by the proposed correlations. • The fitting parameters in model correlations are strongly solvent-dependent. • Intermolecular interactions proved by FTIR are responsible for the dramatic increase in viscosity. Nonaqueous blends of alkanolamines with 2-alkoxyethanols have recently attracted much attention for an energy-efficient CO 2 capture process. In this work, densities and viscosities of partially CO 2 -loaded mixtures of 2- (methylamino)ethanol (MAE) with 2-methoxyethanol (EGME), 2-ethoxyethanol (EGEE) and 2-butoxyethanol (EGBE) were measured at atmospheric pressure over the temperature range of (293.15 to 353.15) K with amine mass fractions of (0.10, 0.30 0.40 and 0.50) containing various CO 2 loading. It was observed that both densities and viscosities of the carbonated solutions showed noticeable changes as increasing CO 2 loading, amine concentration and temperature. Dimensionless parameters from the CO 2 -free and CO 2 -loaded property data were fitted by proposed correlations. The calculated values of density and viscosity from the correlation models matched well with the experimental results of MAE + CO 2 + 2-alkoxyethanols, with AARDs within 0.28% and 2.20% for density and viscosity respectively. These results are useful to evaluate the mass transfer and hydrodynamic performance in a CO 2 capture process using these nonaqueous absorbents. [ABSTRACT FROM AUTHOR]

Abstract: The separation efficiency of butyl acetate (BA) from the wastewater of penicillin plant can be improved by solvent sublation. The mechanism of enrichment of BA at the air–water interface is important to the separation process. The predicted adsorption isotherm from BA solution showed that a molecular adsorption mechanism of BA on the air–water interface alone could not elucidate the high sublation efficiency. The physicochemical properties of the wastewater should be considered to be different from those of BA solution. The stability and microstructure of the wastewater emulsion were studied by both optical microscopy and freeze fracture transmission electron microscopy (FFTEM). The agitated wastewater was relatively an unstable emulsion. It could be mainly stratified into three layers with different microstructures: the upper cream layer, the middle layer and the bottom layer. The upper cream layer was a BA-enriched layer verified by FTIR and gas chromatography. In combination of the physicochemical properties, the emulsion properties played an important role in improving the sublation efficiency. The emulsified BA droplets could be effectively enriched into the organic layer by different mechanisms during the sublation. [Copyright &y& Elsevier]

• Water-lean AAS + EGME blends have proposed as potential absorbents for CO 2 capture. • Physical properties of CO 2 -free and CO 2 -loaded water-lean systems were measured. • Experimental data were well represented by the proposed empirical correlations. • The AADs are within 3.8% for (ρ , η) and 16.6% for CO 2 solubility respectively. Water-lean amino acid salt (AAS) solutions have attracted special attentions for energy-efficient CO 2 absorbents. In this work, 2-methoxyethanol was proposed as a novel anti-solvent due to its excellent properties such as low volatility, low specific heat capacity and low viscosity. Density and viscosity were measured at atmospheric pressure for water-lean blends of potassium sarcosinate (SarK) or potassium L -prolinate (ProK)/water/2-methoxyethanol over the temperature range from (293 to 353) K and the AAS molality up to 4.914 mol·kg−1. Partially CO 2 loaded solutions were also investigated. Equilibrium solubility of CO 2 in AAS/water/2-methoxyethanol solutions was measured in a stirred equilibrium cell at temperatures of (313, 333 and 373) K and CO 2 partial pressures up to 190 kPa. These property data were correlated using empirical correlations as a function of AAS molality, CO 2 molality and/or temperature. The predicted values of density and viscosity matched well with the measured data, with AADs within 0.31% for density and 3.76% for viscosity. The solubility data of CO 2 were fairly fitted with a proposed Soft model. [ABSTRACT FROM AUTHOR]

Nonaqueous CO 2 absorbents, composed of secondary alkanolamines and 2-alkoxyethanols, have attracted much attention for an energy-efficient CO 2 capture process. In this work, densities and viscosities of partially CO 2 -loaded mixtures of 2-(butylamino)ethanol (BAE) + 2-butoxyethanol (EGBE) and 2-(ethylamino)ethanol (EAE) + EGBE were measured at atmospheric pressure over the temperature range of (293.15 to 353.15) K with amine mass fraction (w 1) of (0.10, 0.30 and 0.50) containing various CO 2 loading. With increasing CO 2 loadings, significant increases in both density and viscosity were observed. Dimensionless ρ loaded · ρ CO2-free −1 and η loaded · η CO2-free −1 from the CO 2 -free and CO 2 -loaded systems were fitted by proposed correlations as a function of temperature, amine concentration and CO 2 loading. The calculated values of density and viscosity from the correlations are in good agreement with the experimental results, with AADs within 0.15% and 1.60% for density and viscosity respectively. The dramatic increase in viscosity of carbonated solutions was interpreted by the intermolecular interactions and the formation of ionic products in the mixtures based on the FTIR spectral results. • Densities and viscosities of partially carbonated solutions of EGBE + EAE/ BAE were measured. • Dimensionless ρ loaded · ρ CO2-free −1 and η loaded · η CO2-free −1 were well represented by the proposed correlations. • Strong chemical interactions were confirmed by FTIR as a result of the formation of amine ionic couples. [ABSTRACT FROM AUTHOR]

• Densities and viscosities of EGHE + three secondary alkanolamines were measured. • The V E and Δ η values are negative at the investigated conditions for all three systems. • The sign and magnitude of excess properties was discussed from two opposing aspects. • Experimental data were well represented by the proposed Redlich-Kister correlations. Nonaqueous solvents containing secondary alkanolamines and 2-alkoxyethanols, have recently gained significant attention for energy-efficient CO 2 capture process. However, the information of physicochemical property, particularly involving 2-(hexyloxy)ethanol (EGHE), is very limited for mass transfer and process modeling development. In this work, densities and viscosities were measured for binary mixtures of EGHE with 2-(methylamino)ethanol, 2-(ethylamino)ethanol and 2-(butylamino)ethanol at temperatures of (293.15–353.15)K and atmospheric pressure in the entire concentration range. The excess/deviation properties were derived from the experimental data and fitted by the Redlich-Kister equation to estimate the binary interaction parameters. The variation of excess properties with solvent composition and temperature was also discussed in terms of intermolecular interactions. The calculated from the proposed correlations matched well with the experimental values, with AARDs within 0.01% and 1.60% for density and viscosity respectively. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Mixtures of amines and glycol ethers were proposed as energy efficient CO 2 absorbents. • CO 2 capture performance and reaction mechanisms in nonaqueous systems were explored. • About 50% reduction of solvent regeneration energy was observed for the proposed systems. Abstract High energy consumption for CO 2 capture using aqueous amines is still a major drawback limiting its deployment on a global scale. In this work, the absorption-desorption performance of CO 2 into several blends of monoethanolamine (MEA) or diethanolamine (DEA) with glycol ethers (2-methoxyethanol (2ME) and 2-ethoxyethanol (2EE)) as nonaqueous solvents has been investigated at ambient pressure. Reaction mechanisms and the relative heat duty for these nonaqueous systems were also explored and compared with those of the aqueous MEA. Results showed that the nonaqueous absorbents with 5.0 M MEA had comparable absorption capacity with aqueous 5.0 M MEA and higher desorption efficiency resulting in a larger cyclic capacity (1.45 mol kg−1). Higher partial pressure ratio of CO 2 to solvent vapor under the desorption conditions was also observed for these nonaqueous systems. 13C NMR, FTIR spectra and online conductivity analysis provided evidences that CO 2 can react with MEA in nonaqueous solvents forming the ionic couples (i.e. protonated MEA and carbamate) as well as carbamic acid at high CO 2 loading. The mixture of MEA and 2ME or 2EE could significantly reduce the energy consumption by about 55% as compared to the benchmark aqueous 5.0 M MEA system. [ABSTRACT FROM AUTHOR]

A mixture system of water-lean amino acid salts (AAS) using ethylene glycol (EG) as a solvent has potential use for CO 2 capture to reduce energy consumption. In this work, physicochemical properties such as density, viscosity and N 2 O solubility of potassium prolinate (ProK) or potassium lysinate (LysK) + water + EG solutions were measured over the temperature range from (303.15 to 353.15) K and molality range from (0.481 to 4.331) mol·kg −1 . Partially CO 2 loaded solutions were also investigated. Densities and viscosities of solutions increase with the increasing molality of AAS and CO 2 , but decrease with the increasing temperature. The use of EG in the aqueous AAS systems replacing water can substantially increase the N 2 O solubility. The Henry’s constants of N 2 O for water-lean AAS solutions were calculated and compared with those for aqueous AAS solutions. These experimental data of properties were correlated using empirical correlations as a function of temperature, molality of AAS and/or CO 2 . The experimental results and the predictions from the models matched well each other for both ProK-based and LysK-based water lean systems, with AAD within 0.12% for density, 2.36% for viscosity and 2.0% for N 2 O solubility respectively. [ABSTRACT FROM AUTHOR]

Nitrogen-doped ordered mesoporous carbon spheres (N-OMCs) were conveniently produced by using a soluble urea–phenol–formaldehyde resin as the precursor and triblock copolymer F127 as a soft template. The obtained carbon spheres with a mean diameter of around 240 nm possessed a variable surface nitrogen content of 0.38–1.4 wt.%, an ordered Im 3 m mesostructure, and a uniform pore size of around 2.8 nm. The nitrogen atoms were mostly bound to the graphitic network in two forms, that is, pyridinic and pyrrolic nitrogen, providing adsorption sites for acidic gases. The N-OMC materials exhibited a good performance for the capture of typical acidic gases such as CO 2 (2.43 mmol g −1 ) and SO 2 (119.1 mg g −1 ). [ABSTRACT FROM AUTHOR]

Abstract: Impurities cannot readily be removed during crystallization of avermectin B1a. This study aims to investigate the main impurity effects on the crystallization of avermectin B1a. Impurities, A1a, A2a, B2a and saccharides, were isolated from avermectins crude powder by adsorption column chromatography. Impurity effects on nucleation rate, crystal morphology, and purity of crystals were studied by varying the amount of impurity (0–26.1%, w/w) as well as the relative supersaturation ratio (S, 1.8–2.8). Results showed that A1a, A2a and B2a suppressed primary nucleation. Saccharides promoted nucleation at low supersaturation, while they slightly inhibited nucleation at high supersaturation. A2a and B2a had a marked effect on the crystal morphology, while A1a and the saccharides did not show any significant effect on the crystal morphology. A1a, A2a and B2a could be incorporated into the growing crystals due to the similarity of their structure with the host molecule. [Copyright &y& Elsevier]

Water-lean absorbent has great potential in energy savings over aqueous amines for CO 2 capture. Measurements on density and viscosity for the ternary systems of monoethanolamine (MEA), 2-(methylamino)ethanol (MAE), 2-(ethylamino)ethanol (EAE) or 2-(butylamino)ethanol (BAE) + 2-butoxyethanol (EGBE) + water have been performed at atmospheric pressure and temperatures from 293.15 to 353.15 K. The total amine concentrations in these systems were held at two constant mass fractions in the range of 30-60 mass%. Excess molar volume (V E) and viscosity deviation (Δ η) of the ternary systems were also derived from the experimental data and correlated with Cibulka parameters with the aid of Redlich-Kister equation to fit the measured ternary properties from their pure components. The addition of water into the binary (amine +EGBE) systems can affect greatly the molecular interactions. The V E values of the ternary blends are found to be negative over the investigated conditions. However, Δ η values are observed to be positive except in the rich (amine + EGBE) concentration region. The variations of V E and Δ η were represented and interpreted with molecular interactions and structural effects. • Densities and viscosities of ternary systems (amine + EGBE + H 2 O) were measured. • V E and ∆η of the ternary systems were derived from the experimental property data. • Excess/deviation properties were well represented by the proposed correlations. • Cibulka equation was used to correlate the contribution of the ternary effect. • Intermolecular packing effect and hydrogen bonding can reasonably interpret the results. [ABSTRACT FROM AUTHOR]

Nonaqueous amine-based blends have great potential for energy-efficient CO 2 absorbent. In this work, densities and viscosities were measured for liquid binary mixtures of 2-(ethylamino)ethanol (EAE) and 2-(butylamino)ethanol (BAE) with 2-butoxyethanol (EGBE) at temperatures of (293.15–353.15)K over the entire concentration range and atmospheric pressure. Intermolecular interactions between EGBE and two secondary amines with different carbon chain length were discussed. The excess molar volume (V E), viscosity deviations (∆η) and excess Gibbs free energy (∆G ⁎ E) were calculated from the experimental data and also correlated with the Redlich-Kister equation to estimate the binary interaction parameters. The experimental data and the calculated from the proposed correlations for the studied binary mixtures matched well each other, with AADs within 0.01% and 1.45% for density and viscosity respectively. The variation of excess properties was also discussed in terms of intermolecular interactions. Weak interactions on mixing these binary mixtures with different mass fractions were observed from the FTIR spectra analysis. • Densities and viscosities of binary blends EGBE + secondary alkanolamines (EAE and BAE) were measured. • Excess properties (V E, ∆η and ∆G ⁎ E) of binary mixtures were calculated and well represented by Redlich-Kister correlations. • Weak interactions including intermolecular hydrogen bonding were confirmed by FTIR results. [ABSTRACT FROM AUTHOR]

Densities and viscosities for the binary liquid mixtures of monoethanolamine (MEA) with 2-alkoxyethanols (2-ethoxyethanol (EGEE) and 2-butoxyethanol (EGBE)) were measured over the entire concentration range at temperatures of 293.15–353.15 K and atmospheric pressure. From the experimental results, the excess molar volume (V E), viscosity deviations (∆ η) and excess Gibbs free energy of activation of viscous flow (∆ G ⁎E) were calculated and the excess/deviations properties for the studied binary systems were fitted with the Redlich-Kister equation to estimate the binary interaction parameters. The results were analyzed in terms of intermolecular interactions between unlike molecules and intramolecular interactions within like associated molecules. The densities and viscosities of CO 2 -loaded solutions were also measured and correlated with the proposed correlations. The calculated values of density and viscosity for the binary/ternary systems are in good agreement with the experimental values, with AADs within 0.2% for density and 3.2% for viscosity. The FTIR spectral analysis for the binary mixtures of MEA with 2-alkoxyethanols at various concentrations suggests the presence of weak interactions between component molecules in the systems, and also supports the findings of excess properties. • Densities and viscosities of the binary blends MEA + 2-alkoxyethanols (EGEE and EGBE) were measured. • Densities and viscosities of CO 2 -loaded solutions were reported and correlated with the proposed correlations. • Excess properties (V E, ∆ η and ∆ G ⁎E) of binary mixtures were derived and fitted by Redlich-Kister equation. • Intermolecular interactions were discussed and confirmed by FTIR for the binary systems MEA + 2-alkoxyethanols. [ABSTRACT FROM AUTHOR]