Aqueous Solutions Of Diethanolamine Research Articles

Elucidating flow-directed 98% CO2 absorption using millimeter-sized coiled flow inverters: Nanocellulose-aided sustainable scope

The Sustainable Development Goals (SDGs) adopted by the United Nations drive the global efforts to discover a sustainable carbon capture method for the reduction of anthropogenic CO2 emissions. Concentrated alkanolamine solutions are being used as CO2 capture mediums for batch processes amid several disadvantages, such as energy intensiveness and poor efficiency. In this work, millimeter-sized coiled flow inverters (CFI) have been explored as a point-source CO2 capture tool for highly efficient, continuous operations. Solvent and CO2 gas flow rates are found to dictate the slug flow regime and, more specfically, slug lengths. High interfacial area and residence time remain the driving factors for enhanced CO2 capture using CFI. About 98% CO2 absorption efficiency has been achieved for 3% aqueous diethanolamine solution in CFI . The efficacy of nanocellulose, a sustainable nanomaterial has been unearthed for CO2 capture at low flow rate.

Modeling, Simulation, and Membrane Wetting Estimation in Gas-Liquid Contacting Processes Including Shell-Side Reaction: Biogas Upgrading Using DEA Solution.

The basic principles of a steady-state mass transfer model and the resistance-in-series film model are assessed with the aid of a series of experiments in a gas-liquid contact membrane mini-module (3 M Liqui-Cel MM-1.7 × 5.5) using an aqueous solution of diethanolamine (DEA) of 0.25 M (mol/L) for biogas upgrading. Experimental data show that CO2 removal may exceed 67% and reach 100% in combination with the highest possible recovery of CH4 when employing biogas flow rates in the range of 2.8 × 10-5 - 3.6 × 10-5 m3/s and solvent flow rates within 0.47 × 10-5 - 0.58 × 10-5 m3/s. For the experimental data set, a correlation has been developed, effectively interpolating CO2 removal with the gas and liquid flow rates. The wetting values calculated are concentrated close to each other for the same liquid flow rate without considerably depending on the gas flow rate, especially when applying the Hikita-Yun (reaction rate-shell-side correlation) compared with the Hikita-Costello pair. Furthermore, the calculated wetting diminishes with increasing liquid flow rate, a result that is consistent with previous modeling attempts and relevant literature indications. The assumption of enhanced mass transfer in the liquid-filled part of the membrane pores due to the reaction is scrutinized, leading to objectionable computational wetting values. It is shown that for a concentration of DEA equal to 0.25 M the Hatta numbers and the enhancement factors are not equal in the whole reaction path; thus, the choice of the shell-side correlation has an appreciable impact on the overall analysis, especially for the determination of the wetting values.

Evaluating the Effectiveness of Piperazine on Carbon Dioxide Loading in N-Methyl Diethanolamine Aqueous Solutions and Water/Oil Microemulsions

Evaluating the Effectiveness of Piperazine on Carbon Dioxide Loading in <i>N</i>-Methyl Diethanolamine Aqueous Solutions and Water/Oil Microemulsions

Modeling H2S solubility in aqueous MDEA, MEA and DEA solutions by the electrolyte SRK-CPA EOS

In this study, an electrolyte cubic plus association equation of state (e-CPA EOS) has been proposed to predict the vapor–liquid equilibrium of (H2S) in aqueous solutions of monoethanolamine (MEA), diethanolamine (DEA), and methyldiethanolamine (MDEA). This EOS is composed of repulsive forces, short-range interactions, short-range ionic interactions, association term, long-range ionic interactions, and Born term. The Soave– Redlich– Kwong EOS is used as a non-electrolyte part. A new iterative procedure based on the Jacobi method is introduced to obtain the compositions of all species in the liquid phase. The genetic algorithm (GA) is used to find the optimal values of binary interaction coefficients between molecules and ions. Compared with experimental data, the e-CPA EOS model successfully describes the vapor–liquid equilibrium of H2S in the aqueous solutions of MEA, DEA, and MDEA. The average absolute deviations for 313 data of MEA-H2S-H2O, 156 data of DEA-H2S-H2O, and 145 data of MDEA-H2S-H2O systems were obtained as 8.20 %, 8.04 %, and 9.41 %, respectively. In addition, for some similar cases, the capability of the e-CPA EOS was compared with the Clegg–Pitzer, N-Wilson-NRF, e-NRTL, and e-CTS models. The results indicated that the e-CPA EOS has less error than the four other models.

Energy, exergy, economic, and environmental analysis of natural gas sweetening process using lean vapor compression: a comparison study

Abstract Gas sweetening with an aqueous solution of diethanolamine is a crucial and common process in natural gas processing. However, the process, particularly in the solvent regeneration section, consumes a substantial amount of energy, significantly escalating the cost of gas. This paper presents a simulation and optimization of an existing natural gas refinery plant using a lean vapor compression method. The simulation results indicate that the current process requires 2.73 GJ/tacid gas for solvent regeneration, with exergy destruction of 14,120.59 kW in the solvent regeneration section. The total annualized cost for the current process is 11.68 M$. A modified scheme is proposed to address the issue of high energy consumption and the associated costs. The proposed scheme demonstrates significant improvements in the aforementioned parameters. Specifically, energy for solvent regeneration, exergy destruction in the solvent regeneration section, total annualized cost, and cost of gas are reduced by 16.12 %, 25.04 %, 20.97 %, and 20 % compared to the current process, respectively. These improvements enhance the thermoeconomic indexes, making the proposed scheme a viable and cost-effective alternative to the current process.

Perspectives on the green hybrid blend of diethanolamine-glycerol for post-combustion carbon dioxide capture via a Y-type micro-reactor

CO2 capture by aqueous primary and secondary alkanolamine solutions is a recognized technology in industrial CO2 separation processes. Yet, certain obstacles caused by high-energy consumption due to the amine regeneration demands, and the formation of thermally stable salts require to be overcome for the development of these solvents. In this paper, glycerol, as a beneficial by-product of biodiesel production, has been introduced as a second promising CO2 absorbent for aqueous diethanolamine solution in a Y-type micro-reactor with dimensions of 800 µm × 4 cm × 19 cm. The experiments of CO2 capture into the hybrid blend of DEA-Glycerol were investigated at ambient pressure and the operating temperature of 25–45 °C, volumetric gas flow rate of 100–300 ml/min, DEA concentrations of 1.5–2.5 M, and glycerol concentrations of 5–15%wt. Experimental results demonstrated that adding 10 wt% glycerol in the aqueous blend of 2.5 M DEA-Glycerol boosts the CO2 removal percentage, RP, up to 96.89%, and enhances the volumetric overall gas-phase mass transfer coefficient, KGaV, and volumetric mass transfer flux, NAaV, to 34.89 kmol/m3.h.kPa and 88.04 kmol/h.m3, respectively. Furthermore, based on the Box-Behnken statistical responses, under the constant concentration of 2 M of DEA, increasing the presence of glycerol from 5 to 10 wt% in the hybrid blend of DEA-Gly can intensify the CO2 RP, KGaV, and NAaV values by 2.12% and 8.66%, and 1.80%, respectively, illustrating the glycerol contribution on the CO2 capture process.

Stabilization of [BMIM][PF6] ionic liquid membrane in structurally optimized multilayer ceramic support through aqueous DEA solution for CO2/CH4 separation

The stability of the ceramic supported liquid membranes (SLMs) is one of the most interesting research subjects. In this work, the SLMs’ stability for CO2/CH4 separation was investigated. Following pressing α-Al2O3 substrates at 400, 600, and 800 bar, colloidal and polymeric TiO2 intermediate and top layers were coated. Aqueous diethanolamine (DEA) solution was used as solvent in the SLM to optimize support structure based on CO2/CH4 separation performance. The pressed support at 800 bar and coated with TiO2 demonstrated best performance and selected for further study. Subsequently, 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]) ionic liquid (IL) was immobilized inside the selected support and used as the supported ionic liquid membrane (SILM) for CO2/CH4 separation. The SILM separation performance was evaluated under different pressures and temperatures. Temperature was found to has greater effect than pressure due to a decrease in IL's viscosity and an increase in penetrant diffusivity. At 25 °C and 1 bar, SILM exhibited consistent and reliable performance as CO2 and CH4 permeabilities of 244.0 and 7.4 Barrer, respectively, and CO2/CH4 selectivity of 33.0 over 6 h. The findings contribute to understanding the implementation of multilayer ceramic SILMs for CO2/CH4 separation and highlight its potential along with opening up new avenues.

The comparative modeling of solubility of carbon dioxide in amine solutions using SAFT-HR and PC-SAFT equation of state

In this paper, we applied PC-SAFT and SAFT-HR equations of state so as to reproduce the solubility of carbon dioxide in aqueous diethanolamine solution. By using these equations, we have been able to model the solubility of carbon dioxide in aqueous amine solution in more than 350 experimental data points with wide range of amine molar concentration (0.01–0.12), temperature (300 K –478 K), carbon dioxide partial pressure (0.0001 KPa –5473 KPa), and carbon dioxide loading (0.04 –1.1). Ternary systems including water, carbon dioxide and diethanolamine have also been modeled by PC-SAFT and SAFT-HR equations of state based on bubble pressure algorithm. Binary interaction parameters are set to zero to show the genuine capability of equations of state in reproducing such experimental data. Provided modeling results have been obtained from MATLAB R2019b software for PC-SAFT equation of state are less deviated with experimental data. Overall average relative deviation of SAFT-HR and PC-SAFT are 45.452% and 4.374% respectively which show that PC-SAFT is a robust equation of state in predicting the solubility data of carbon dioxide in aqueous alkanolamine solutions.

Experimental investigation on CO2 desorption kinetics from MDEA + PZ and comparison with MDEA/MDEA + DEA aqueous solutions with thermo‐gravimetric analysis method

AbstractThe carbon dioxide discharged from fossil fuels combustion products is considered as a major contributor to global warming. The current investigation aimed at CO2 desorption kinetics in 3.25 mol L–1 methyldiethanolamine (MDEA)–0.1 mol L–1 piperazine (PZ) rich amine aqueous solution with thermo‐gravimetric analysis (TGA) method under different heating rates of 2.5, 5, 10, and 20 °C min–1. The kinetics parameters were determined by comparison of 40 mechanism functions with thermal analysis kinetic method. The average activation energy E was 59.16 kJ mol–1, preexponential factor A was 5.54 × 108, and the most probable mechanism function was G(α) = [–ln(1 – α)]3/2. In addition, the kinetic parameters of CO2 desorption process from three rich amine aqueous solutions (MDEA, MDEA + diethanolamine(DEA), MDEA + PZ) were compared and the influence of kinetic parameters was further discussed. The desorption rate models of three rich amine aqueous solutions were established and desorption rates were well predicted. The order of desorption rate inferred from desorption rate model was MDEA &gt; MDEA + DEA &gt; MDEA + PZ. The results indicated that TGA combined with thermal analysis kinetics was an effective and quick method with high accuracy, easy operation, and good repeatability for screening absorbents preliminarily in laboratory. © 2021 Society of Chemical Industry and John Wiley &amp; Sons, Ltd.

Simulation and Optimization of the Acid Gas Absorption Process by an Aqueous Diethanolamine Solution in a Natural Gas Sweetening Unit.

The presence of carbon dioxide in natural gases can lower the quality of natural gas and can cause CO2 freezing problems. Therefore, using reliable techniques for the reduction and elimination of carbon dioxide from natural gases is necessary. The aqueous diethanol amine (DEA) solution’s ability to simultaneously absorb H2S and CO2 from sour natural gases makes it possible to use this solution in the natural gas sweetening process. The goal of this work was to determine the maximum amount of the removed CO2 by an aqueous DEA solution in one of the gas sweetening plants of the National Iranian South Oilfields Company (NISOC). For this purpose, based on the obtained designed experiment results using the L9 orthogonal array Taguchi method, the experiments were conducted and three levels of amine concentrations (25, 28, and 30 wt %), temperatures (40, 50, and 60 °C), and circulation rates of lean amine (220, 240, and 260 m3 h–1) were considered as the key operational parameters on CO2 removal. To evaluate the ability of the HYSYS simulation software and the Kent–Eisenberg thermodynamic model to predict CO2 absorption by an aqueous DEA solution in the gas sweetening process, the field data were compared with the results of the simulation. It was observed that the maximum removal of CO2 is achieved at a lean amine concentration of 30 wt %, a temperature of 40 °C, and a circulation rate of 260 m3 h–1. Also, the experimental results indicate that the effects of the selected process variables on CO2 absorption are not linear and the most effective parameter on carbon dioxide removal is the concentration of amine in an aqueous solution and the temperature of the lean amine has the least effect. Besides, the obtained simulation results are in the range of the unit design basis but have some deviations from field data. The findings of this study can help in better understanding of the selection of the effective variables in the natural gas sweetening process and obtaining their appropriate values to achieve the highest efficiency.

Effects of diethanolamine and ethylene glycol + diethanolamine aqueous solutions on methane hydrate stability conditions: Experimental measurements and thermodynamic modeling

In this work, a total of 83 dissociation conditions data of methane hydrate in the attendance of diethanolamine (DEA) and diethanolamine + ethylene glycol (EG) aqueous solutions were first experimentally measured: 45 data for DEA and 38 data for DEA + EG aqueous solutions. The data were measured using a stainless steel (SS–316) cell by employing an isochoric pressure-search method. The methane hydrate stability conditions in various aqueous systems containing 0.09, 0.15, 0.25 mass fractions of DEA, (0.05 mass fraction of DEA + 0.05 mass fraction of EG), (0.05 mass fraction of DEA + 0.10 mass fraction of EG), and (0.15 mass fraction of DEA + 0.10 mass fraction of EG) were measured in the pressure range of 3.23–8.38 MPa and the temperature range of 274.1–283.0 K. It was observed that DEA causes thermodynamic inhibition of methane hydrate formation, and using 0.25 mass fraction of DEA in an aqueous solution shifts the methane hydrate stability temperatures to about 4.2 K. Also, it was concluded that although DEA has weaker strength compared to EG, it can be used as a gas sweetening agent and thermodynamic hydrate inhibitor. For modeling purpose, the van der Waals–Platteeuw (vdWP) model was employed for the hydrate phase, the Peng-Robinson equation of state (PR EoS) was utilized to compute the methane fugacity in the gas phase, and the NRTL activity coefficient model was applied to calculate the nonideality of the aqueous phase. The AAEs (K) obtained from this thermodynamic model for DEA and DEA + EG aqueous solutions are 0.2 and 0.4, respectively.

Solubility of CO2 in Aqueous Solutions of Diethanolamine (DEA) and Choline Chloride

In this study, the solubility of CO2 in DEA in the presence and absence of choline chloride was reported at different temperatures of 276.15, 298.15, 313.15, and 333.15 K, and pressure range of 4-15 bar. The solubility of CO2 was evaluated using the pressure decay method in a batch isochoric stirred absorption cell. Also, the design of experiments performed with Qualitek-4 software using the Taguchi method. Henry’s law constants at three different temperatures were calculated from the correlation of solubility data. Results showed that increasing the initial pressure and DEA concentration and also decreasing the temperature, increases the solubility of CO2. Optimum operating conditions to maximize the amount of CO2 absorption including the temperature of 276.15 K (minimum level), the initial pressure of 15 bar (maximum level), the concentration of DEA of 40 wt.% (maximum level), and the concentration of choline chloride of 5 wt.% (middle level). Also, Qualitek-4 software predicted the amount of solubility at the optimum conditions which was 7.5% different from the measured value.

CO2 absorption into aqueous diethanolamine solution with nano heavy metal oxide particles using stirrer bubble column: Hydrodynamics and mass transfer

Abstract In this research, the TiO2, ZnO, and ZrO2 nanofluids based on the DEA solution were provided exploiting the ultrasonic dispersion system to investigate the impact of the nano-particles on the CO2 absorption in a continuously stirred bubble column. The nano-particle concentration was determined in the range 0.01−0.10 wt%,. Bubble size distribution along column axis measurements was carried out using the high-speed digital camera. The influences of several factors such as CO2 partial pressure, solid loading, nanoparticle type, and stirring speed on the hydrodynamic characteristics and CO2 absorption performance were examined in detail. The presence of nanoparticles increased the gas holdup and interfacial area up to optimum value and then had a negligible effect. The stirrer speed increased the gas holdup and interfacial area up to optimum value and then decreased. Furthermore, the results showed that the adding nanoparticles in the range of 0.01−0.1 wt% increased CO2 absorption efficiency between 25.2–43.8% and the optimum value of nanoparticles can be an effective key parameter at the absorption phenomena into a dilute amine solution. Also, it was determined that at optimum stirrer speed, the removal efficiency of ZnO, TiO2, and ZrO2 nanofluids was caused an increase of about 12.1 % 8.0 %, and 13.3 %, respectively.

Effect of different PVDF and additives on the properties of hollow fiber membranes contactors for CO2 separation

AbstractIn the present work, different poly(vinil fluoride) (PVDF) were selected for preparing membranes, based on the fact that they are able to form polymer solutions with different viscosities. This characteristic can affect spinning, as well as, mass transfer between the polymer solution and precipitation bath; therefore, each PVDF solution can differently affect membrane formation. The effect of different additives in the polymer solutions was also investigated. Flat sheet and hollow fiber membranes were characterized by Scanning Electron Microscopy analysis, contact angle, gas permeation, porosity, and membrane gas–liquid contactor tests, aiming carbon dioxide removal. The hollow fibers prepared by the polymer which formed a less viscous solution (named PVDF‐I) had a faster light transmittance decay, which started around 150 s before the more viscous solution (PVDF‐II). Hollow fibers obtained using PVDF‐I and propionic acid, in the polymer solution, presented the best gas–liquid contactor performance. CO2 removal increased from 21 to 35.1%, for PVDF‐II and PVDF‐I, respectively, using aqueous diethanolamine solution, as absorbent liquid. In conclusion, even though PVDF‐I and PVDF‐II membranes were obtained by using the same spinning conditions and experimental methodology, the difference between the polymers properties certainly affected the final membrane morphology and transport properties.

Carbon dioxide desorption from aqueous solutions of monoethanolamine and diethanolamine in a microchannel reactor

In this study, the process of carbon dioxide (CO2) desorption from two saturated solutions of monoethanolamine (MEA) and diethanolamine (DEA) was performed in a microchannel made of stainless-steel grade 316 with a circular cross-section (diameter: 800 μm, length: 35 cm). The operating variables in this study were temperature (55, 75 and 95 °C), rich solvent flow rate (0.3, 0.9 and 1.5 ml/min), and inlet solvent concentration (10, 20 and 30 wt% of the amine). The mass transfer efficiency was determined based on the desorption percentage, volumetric liquid-side mass transfer coefficient (kLaV), volumetric overall mass transfer flux (NCO2aV), and energy consumption per unit mass CO2 (R). The results showed that the use of a microchannel significantly increased the mass transfer rate and decreased energy consumption per removed CO2. The results also showed that the amount of kLaV for the two solvents of MEA and DEA was 1.91 and 3.48 1/s, respectively. Moreover, the R-value for the two solvents of MEA and DEA was 1.3 and 1.63 MJ/kg CO2, respectively, which is at least three times lower than that of other mass transfer devices.

Experimental Mutual Solubility Data for Cyclohexane and Water in Aqueous Solutions of Diethanolamine

This study presents liquid–liquid equilibrium solubility data of the mutual solubility of cyclohexane and water in aqueous solutions of diethanolamine (DEA). Measurements were taken using a series of jacketed cells connected to a thermostat to maintain the desired solubility temperature. Different concentrations of DEA (15, 25, 35, 45, and 50 wt %) were prepared and mixed with cyclohexane in the measuring cells at temperatures ranging from 298 to 318 K and atmospheric pressure. Once thermodynamic equilibrium had reached, samples from the aqueous phase were analyzed for cyclohexane content using a gas chromatograph-mass spectrometer, while samples from the hydrocarbon-rich phase were analyzed using a water content apparatus. Results showed that the solubility of cyclohexane increased with an increase in DEA concentration and varied directly with the temperature. Similarly, the solubility of water in the organic phase exhibited an increasing trend with an increase in temperature and concentration of DEA. The alkanolamine concentration effect was modeled using an activity coefficient model that was successfully used to estimate the activity coefficient of cyclohexane in the aqueous DEA phase from the measured solubility data.

Fabrication and characterization of poly(vinylidene fluoride)–polytetrafluoroethylene composite membrane for CO2 absorption in gas–liquid contacting process

ABSTRACTThe wetting resistance of poly(vinylidene fluoride) (PVDF) membrane is a critical factor which determines the carbon dioxide (CO2) absorption performance of the gas–liquid membrane contactors. In this study, the composite PVDF–polytetrafluoroethylene (PTFE) hollow fiber membranes were fabricated through dry‐jet wet phase‐inversion method by dispersing PTFE nanoparticles into PVDF solution and adopting phosphoric acid as nonsolvent additive. Compared with the PVDF membrane, the composite membranes presented higher CO2 absorption flux due to their higher effective surface porosity and surface hydrophobicity. The composite membrane with addition of 5 wt % PTFE in the dope gained the optimum CO2 absorption flux of 9.84 × 10−4 and 2.02 × 10−3 mol m−2 s−1 at an inlet gas (CO2/N2 = 19/81, v/v) flow rate of 100 mL min−1 by using distilled water and aqueous diethanolamine solution, respectively. Moreover, the 5% PTFE membrane showed better long‐term stability than the PVDF membrane regardless of different types of absorbent, indicating that polymer blending demonstrates great potential for gas separation. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47767.

An Experimental Study of a Hollow-Fiber Membrane-Contacting System for Carbon Dioxide/Methane Separation

Summary Separation of carbon dioxide (CO2) from methane (CH4) using a gas/liquid membrane-contacting system is a promising alternative to conventional absorption techniques, such as wet scrubbers. The main objective of this research was to design, develop, and implement a hollow-fiber membrane-contacting system to absorb and separate CO2 from CH4 in a simulated flare-gas stream. A gas/liquid contacting system was constructed using microporous polytetrafluoroethylene (PTFE) hollow fibers as a highly hydrophobic membrane. The module used for the experimental studies had 51-mm diameter and 200-mm effective length. The membrane module had a packing density of 60%, and the PTFE hollow fiber used in this module had a mean pore size of 0.48 µm. Experiments were conducted in a laboratory-scale plant fed with a simulated flare-gas mixture containing 2.5% CO2 balanced with CH4 that could produce varying concentrations of inlet gas using a mass-flow controller. CO2-separation-experimentation studies were performed, and the effect of operational variables on the separation efficiency of the system has been studied. To optimize the gas-separation performance of the membrane module, the effects of gas/liquid-flow rates, the concentration of absorbent, and the nature of the scrubbing liquid were examined. The absorption efficiency of deionized (DI) water and aqueous solutions of sodium hydroxide (NaOH) and diethanolamine (DEA) as the physical and chemical absorbents were compared. Results indicated that increasing the flow rate and concentration of the scrubbing liquid can enhance the separation efficiency; however, increasing the flow rates of the gas phase had a negative effect on the CO2-absorption performance of the system. The conventional chemical-absorption processes for the separation of CO2 have many drawbacks, such as flooding, channeling, and foaming that can impair the mass transfer between gas and liquid, and possible equipment failure caused by corrosion. Membrane processes can offer attractive opportunities for gas-treatment applications, including removal of acidic-gas compounds from flare-gas streams that can help to mitigate the adverse health effects associated with burning the waste gases.

Modeling CO2 absorption in aqueous solutions of DEA, MDEA, and DEA + MDEA based on intelligent methods

ABSTRACTRemoving CO2 as an acidic-potential component from different gaseous flows is a main topic in different industries producing green-house gases, especially in natural gas sweetening units. A group of well-known absorbents for CO2 are the amine solutions. The common amine compounds consisting di-ethanolamine (DEA), methyl-di-ethanolamine (MDEA), and their mixture in aqueous solution have been investigated in this study. The effort was to develop new models for estimation of CO2 loading capacity of the presented amine solutions using genetic programing (GP) and stochastic gradient boosting (SGB) trees as two advanced and novel machine learning approaches in this area. A total of 175 sets of experimental data of CO2 absorption including independent variables (temperature, CO2 partial pressure, concentrations of DEA and MDEA in water) and objective function (CO2 loading capacity) were collected from literature and fed to the mentioned algorithms (GP and SGB) as input dataset. Then, each algorithm was run over the dataset, separately and two new models were created. Finally, strict statistical evaluations were implemented to assess the estimating capability of the new models. The statistical parameters including correlation coefficients (R2 SGB = 0.99848 and R2 GP = 0.99087), root-mean-square deviations (RMSDSGB = 0.00903 mol/mol and RMSDGP = 0.02244 mol/mol) and average absolute relative deviations (AARDSGB = 0.95628% and AARDGP = 8.71909%) show that the utilized powerful algorithms have enhanced the applicability of the new developed models providing good` estimations in operational processes. Final results show superiority and more accuracy of the new SGB model for confident predictions in amine process.

Solubility Determination and Thermodynamic Modeling for the System NaCl–NH4Cl–Diethanolamine–H2O

In this work, the solubility behavior of salts NaCl and NH4Cl was investigated in aqueous diethanolamine (DEA) solution by varying both temperature and the solvent composition. DEA has been prevalently used in the postcombustion process to capture CO2, but a limited amount of references can be found pertaining to any solid–liquid system containing DEA. It was experimentally determined that the solubility of NaCl decreases, whereas the solubility of NH4Cl increases with the addition of DEA (x′DEA = 0–0.2). The solubility of both salts increases if temperature is raised from 283 to 353 K. The common-ion effect was examined for the quaternary system when both salts are present in the solution. By the regression of solubility data with the Mixed Solvent Electrolyte model, we proved that readjusting the middle-range interaction parameters between Cl–-DEA and DEAH+-Cl– would lower the relative deviation (within 5%) for each proposed ternary system. A comprehensive chemical model was further constructed based on...