Solubility Of Succinic Acid Research Articles

Selection of competitive adsorption additives to relieve product inhibition of maleic acid hydrogenation in proton exchange membrane flow cell reactor: A molecular dynamics simulation

Adsorption of products on carbon carriers and the sluggish mass transport of products in the catalytic layer lead to product inhibition in proton exchange membrane flow cell reactor (PEMFCR), which seriously decreases hydrogenation performance. Here, via molecular dynamics simulations, an alleviative mechanism of competitive adsorption additives on product inhibition is proposed by choosing biomass derivatives maleic acid (MA) as hydrogenation model compound and ethanol (EtOH) as an additive model. The enhanced solvation and competitive adsorption synergistically promote the outflow of product succinic acid (SA) from the catalytic layer. Strong hydrophobic-hydrophobic interactions between EtOH and SA promote solvation and solubility of SA in the solvent water, and meanwhile the competitive adsorption steric hindrance of EtOH on adsorption interfaces weakens van der Waals interactions between SA and carbon carriers. Accordingly, the main structural characteristics that influence competitive adsorption of additives, such as, amphiphilic structure, polarity, molecular weight, and size of hydrophobic moiety, are exacted for selection of favorable additives. Among the studied water miscible alcohol and ketone additives, isopropanol (iPrOH) is proved to be favorable, which is further verified by the highest increase (64.3%) of hydrogenation conversion of MA in experiments. This work could provide theoretical guidance for selecting high-performance additives, intensifying heterogeneous hydrogenation in PEMFCR.

Measurement and correlation for solubilities of succinic acid, glutaric acid and adipic acid in five organic solvents

In this study, the solid-liquid equilibrium (SLE) data of succinic acid (SA) and glutaric acid (GA) and adipic acid (AA) in N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAC), dimethyl sulfoxide (DMSO), 1-Methyl-2-pyrrolidinone (NMP) and sulfolane were determined by using the method of dynamic laser at atmospheric pressure. The experimental SLE data indicates that within the temperature range studied (286.25–358.75 K), the solubilities of SA, GA and AA in above five solvents is proportional to the temperature. Meanwhile, three thermodynamic models (Apelblat model, λh model, the modified nonrandom two liquid (NRTL) activity coefficient model) were used to correlate the experimental data, the results show that the correlated data is generally consistent with the experimental data. The result of Akaike Information Criterion (AIC) analysis filter out the best model for every system. In addition, the thermodynamic functions (dissolution enthalpy, entropy, Gibbs energy) were obtained from the SLE data by calculating the van't Hoff equation.

Solubility of succinic acid, glutaric acid and adipic acid in propionic acid + ε-caprolactone + water mixtures: Experimental measurement and thermodynamic modeling

The solubilities of succinic acid, glutaric acid and adipic acid in propionic acid + water solvent mixtures at 304.25–354.65 K, and in propionic acid + ε-caprolactone + water solvent mixtures at 297.65–351.25 K were determined by the synthetic method at atmospheric pressure. The experimental data in propionic acid + water solvent mixtures were correlated by the modified Apelblat equation and modified nonrandom two-liquid (NRTL) activity coefficient model. The results showed that the calculated solubility data by the modified NRTL models had a better agreement with the experimental data, and the value of average relative deviation was 1.923%. And the solubilities of succinic acid, glutaric acid and adipic acid in ternary propionic acid + ε-caprolactone + water solvent mixtures predicted by the modified NRTL model agree with the experimentally determined results satisfactorily, which showed that the modified NRTL model would be suitable model for predicting the solubilities of succinic acid, glutaric acid and adipic acid in propionic acid + ε-caprolactone + water.Furthermore, the thermodynamic functions including dissolution enthalpy, entropy and Gibbs energy were obtained from the solubility data by using the van't Hoff equation.

Solubility of succinic acid, glutaric acid and adipic acid in propionic acid + ε-caprolactone mixtures and propionic acid + cyclohexanone mixtures: Experimental measurement and thermodynamic modeling

By dynamic laser method, the solubilities of succinic acid, glutaric acid and adipic acid in propionic acid + ε-caprolactone mixtures and propionic acid + cyclohexanone mixtures were determined under atmospheric pressure. The experimental temperature ranged from 283.95 to 340.45 K, and the mass fraction of propionic acid in the solvent mixtures ranged from 0.00 to 1.00 respectively. It was found that when the solvent composition is constant, the solubilities of succinic acid, glutaric acid and adipic acid would increases with the increase of the temperature. What is more, at constant temperature, with the mass fraction of propionic acid in mixtures increasing, the solubilities of glutaric acid and adipic acid increase gradually, on the contrary, the solubility of succinic acid decrease gradually. The experimental data were correlated by the modified Apelblat equation and the modified nonrandom two-liquid (NRTL) activity coefficient models. The maximum value of average relative deviation was 3.015%, which shows the values of the solubility calculated showed good agreement with the experimental observations. Furthermore, the thermodynamic functions including dissolution enthalpy, entropy and Gibbs energy were obtained from the solubility data by using the van't Hoff equation.

Determination and Correlation for the Solubilities of Succinic Acid in Cyclohexanol + Cyclohexanone + Cyclohexane Solvent Mixtures

The solubilities of succinic acid in binary cyclohexanone + cyclohexanol solvent mixtures at 304.25–354.65 K, in binary cyclohexane + cyclohexanol solvent mixtures at 300.15–346.15 K, in binary cyclohexane + cyclohexanone solvent mixtures at 297.65–351.25 K, and in ternary cyclohexanol + cyclohexanone + cyclohexane solvent mixtures at 306.95–343.15 K were determined by the synthetic method at atmospheric pressure. The experimental solubility data in binary solvent mixtures were correlated by the Apelblat equation and nonrandom two-liquid (NRTL) activity coefficient model, and the calculated solubility data by the models have a good agreement with the experimental data. Then, the solubilities of succinic acid in ternary cyclohexanol + cyclohexanone + cyclohexane solvent mixtures were predicted by the NRTL model and compared with the experimental solubility data. Finally, the solubilities of succinic acid in the three studied binary solvent mixtures were compared with the solubilities of glutaric acid and a...

Binary and ternary solid-liquid phase equilibrium for the systems formed by succinic acid, urea and diethylene glycol: Determination and modelling

In this work, the solid-liquid phase equilibrium for binary system of succinic acid+diethylene glycol at the temperatures ranging from (298.15 to 333.15)K and ternary system of (succinic acid+urea+diethylene glycol) at 298.15K, 313.15K and 333.15K was built by using the isothermal saturation method under atmospheric pressure (101.2kPa), and the solubilities were determined by a high-performance liquid chromatography. The solid-phases formed in the ternary system of ((succinic acid+urea+diethylene glycol)) were confirmed by Schreinemaker’s method of wet residue, which corresponded to urea, succinic acid, and adduct 2:1 urea-succinic acid (mole ratio). Three isothermal phase diagrams for the ternary system were constructed based on the measured mutual solubility. Each isothermal phase diagram included six crystallization fields, three invariant curves, two invariant points and two co-saturated points. The crystalline region of adduct 2:1 urea-succinic acid is larger than those of the other two solids. The solubility of succinic acid in diethylene glycol was correlated with the modified Apelblat equation, λh equation and NRTL model; and the mutual solubility of the ternary ((succinic acid+urea+diethylene glycol)) system was correlated and calculated by the NRTL model. The interaction parameters’ values of succinic acid-urea were acquired. The value of RMSD was 7.11×10−3 for the ternary system. The calculation results had good agreement with the experiment values. Furthermore, the densities of equilibrium liquid phase were acquired. The phase diagrams and the thermodynamic model of the ternary system could provide the basis for design of the adductive crystallization process which was used to separate succinic acid with high purity from dicarboxylic acid mixtures.

Determination and Correlation of Solubilities for Succinic Acid in the Adipic Acid + Glutaric Acid + Acetone Mixture and Adipic Acid in the Succinic Acid + Glutaric Acid + Acetone Mixture

To provide fundamental thermodynamic data for the crystallization separation of succinic acid and adipic acid from mixed dibasic acid, the solubilities of succinic acid in various mass fractions of the adipic acid + glutaric acid + acetone mixture and adipic acid in various mass fractions of the succinic acid + glutaric acid + acetone mixture were measured by the dynamic method at a temperature range of 277.85–327.95 K under atmospheric pressure. The results showed that the solubility of succinic acid in acetone increased with increasing mass fraction of adipic acid and glutaric acid in the mixed solvent at the same temperature. Similarly, the solubility of adipic acid in acetone increased with increasing mass fraction of succinic acid and glutaric acid in the mixed solvent at the same temperature. The ideal solution equation, Apelblat equation, λh equation, and nonrandom two-liquid (NRTL) equation were applied to correlate the experimental solubility data, which were all in good agreement with the four e...

Solubilities of Succinic Acid in Acetic Acid + Water Mixtures and Acetic Acid + Cyclohexane Mixtures

The solubilities of succinic acid in acetic acid + water solvent mixtures at (303.2 to 333.2) K and acetic acid + cyclohexane solvent mixtures at (303.2 to 343.2) K were determined. It was found that the solubility of succinic acid in acetic acid + cyclohexane mixtures increases with increasing mass fraction of acetic acid at constant temperature. However, for the system of acetic acid + water solvent mixtures, acetic acid with the mass fraction of 0.20 shows the best dissolving capacity for succinic acid. The experimental data were well-correlated with universal quasi-chemical (UNIQUAC) equations, and the solubilities calculated by the model were in good agreement with experimental data.

Solubility of succinic acid in different aqueous solvent mixtures: Experimental measurement and thermodynamic modeling

Data on corresponding solid–liquid equilibrium of succinic acid in different aqueous solvent mixtures was measured with temperature range from 278.15K to 333.15K under atmospheric pressure by employing the gravimetric method. The experimental results indicated that the solubility of succinic acid in the binary mixtures increases with increasing both temperature and mass fraction of organic solvents. The experimental data were well-correlated with the modified Apelblat equation, the λh equation and the van’t Hoff equation. In addition, the calculated solubilities showed good agreement with the experimental results. It was found that the modified Apelblat equation could obtain the better correlation results than the other two models. The standard enthalpy, standard entropy, and Gibbs free energy change of solution of succinic acid were calculated from the solubility data by using the modified Apelblat model. Moreover, the experimental data and model parameters would be useful for optimizing the process of purification of succinic acid in industry.

Solubility of Succinic Acid in Ethanol Plus Water Systems from 278.15 K to 333.15 K

In an equilibrium vessel, the solubilities of succinic acid in binary aqueous ethanol solvents were measured by the analytical stirred-flask method with the temperature ranging from 278.15 to 333.15 K at atmospheric pressure. Data on the corresponding solid–liquid equilibrium of succinic acid in binary aqueous ethanol solutions are essential for industrial design and further theoretical studies. The effect of solvent composition and temperature on the solubility is discussed. The solubility data were correlated with the Combined Nearly Ideal Binary Solvent/Redlich-Kister (CNIBS/R-K) model. The solubility measured in this study can be used for succinic acid purification or optical resolution by the preferential crystallization procedure.

Solubility of Succinic Acid in Binary Mixtures

Solubility of Succinic Acid in Binary Mixtures