Binary Acetic Acid Research Articles

Solubilities of 2,5-Furandicarboxylic Acid in Binary Acetic Acid + Water, Methanol + Water, and Ethanol + Water Solvent Mixtures

The solubilities of 2,5-furandicarboxylic acid (FDCA) in binary acetic acid + water, methanol + water, and ethanol + water solvent mixtures were measured by a static analytical method with the mass fraction of water in the solvent varying from 0 to 0.3 at atmospheric pressure. Furthermore, the molar enthalpy of fusion (ΔfusH = 55.131 kJ/mol) and fusion temperature (Tfus = 614.45 K) of FDCA were determined by differential scanning calorimetry. The non-random two liquid (NRTL) model and the measured parameters were used to correlate these solubility data, and the relevant parameters were regressed by the least-squares method. The NRTL model was found to provide a satisfactory representation of the experimental data.

Measurement and correlation for solubilities of isophthalic acid and m-toluic acid in binary acetic acid + water and acetic acid + m-xylene solvent mixtures

In this study, the solubilities of isophthalic acid (IPA) and m-toluic acid (m-TA) in binary acetic acid (HAc) + (water or m-xylene) solvent mixtures were measured by using a synthetic method at atmospheric pressure. The mole fraction of HAc in the corresponding solvent mixtures ranges from 0.0000 to 1.000. The measured data show that within the temperature range studied, the solubilities of IPA and m-TA increase with increasing temperature at constant solvent composition. At a given temperature, the solubilities of IPA and m-TA decrease with the decreasing mole fraction of HAc in HAc + water solvent mixtures; whereas the “maximum-solubility effect” was observed in HAc + m-xylene solvent mixtures, and that with the mole fraction of HAc at 0.8761 has the best dissolving capacity for IPA at constant temperature. The experimental solubilities were well correlated by both the nonrandom two-liquid (NRTL) and Apelblat equations, and the calculated solubilities agree satisfactorily with the measured results. Furthermore, the thermodynamic functions including dissolution enthalpy, entropy and Gibbs energy were obtained from the solubility data by using the van't Hoff equation.

Solubilities of Phthalic Acid and o-Toluic Acid in Binary Acetic Acid + Water and Acetic Acid + o-Xylene Solvent Mixtures

The solubilities of phthalic acid and o-toluic acid in binary acetic acid (HAc) + water and HAc + o-xylene solvent mixtures were measured by a dissolution temperature method at atmospheric pressure. The mole fractions of HAc in the corresponding solvent mixtures range from 0.00 to 1.00. The measured data show that, within the temperature range studied, the solubilities of phthalic acid and o-toluic acid increase with the increasing temperature at constant solvent composition and initially decrease with the decreasing mole fraction of HAc in HAc + o-xylene and HAc + water solvent mixtures at constant temperature, respectively. It also shows that, within the solvent composition range studied, the HAc + water solvent mixtures with the mole fraction of HAc at 0.5467 has the highest dissolving capacity for phthalic acid at constant temperature, and the highest solubility of o-toluic acid is obtained in HAc + o-xylene solvent mixtures with the mole fraction of HAc of 0.5408 at constant temperature. The experime...

Solubilities of Isophthalic Acid in Acetic Acid + Water Solvent Mixtures

The solubilities of isophthalic acid (1) in binary acetic acid (2) + water (3) solvent mixtures were determined in a pressurized vessel. The temperature range was from 373.2 to 473.2K and the range of the mole fraction of acetic acid in the solvent mixtures was from x2 = 0 to 1. A new method to measure the solubility was developed, which solved the problem of sampling at high temperature. The experimental results indicated that within the temperature range studied, the solubilities of isophthalic acid in all mixtures showed an increasing trend with increasing temperature. The experimental solubilities were correlated by the Buchowski equation, and the calculate results showed good agreement with the experimental solubilities. Furthermore, the mixed solvent systems were found to exhibit a maximum solubility effect on the solubility, which may be attributed to the intermolecular association between the solute and the solvent mixture. The maximum solubility effect was well modeled by the modified Wilson equation.

Solubilities of 1,3,5-Benzenetricarboxylic Acid and 1,3-Benzenedicarboxylic Acid in Acetic Acid + Water Solvent Mixtures

Using the static analytical method, the solubilities of 1,3,5-benzenetricarboxylic acid and 1,3-benzenedicarboxylic acid in binary acetic acid (2) + water (3) solvent mixtures have been measured. The experimental temperature ranged from (303.2 to 363.2) K, and the mole fraction of acetic acid in the solvent mixtures ranged from (0.411 to 1.000) for 1,3,5-benzenetricarboxylic acid and x2 = (0.310 to 1.000) for 1,3-benzenedicarboxylic acid. The experimental results showed that, within the temperature range of the measurements, the solubilities of 1,3,5-benzenetricarboxylic acid and 1,3-benzenedicarboxylic acid in all the mixtures showed an increasing trend as the temperature increased. The solubility of 1,3,5-benzenetricarboxylic acid increased with the increasing mole fraction of water. Below 323.2 K, as the mole fraction of water increased in the aqueous acetic acid solution, the solubility of 1,3-benzenedicarboxylic acid decreased within the range of measurements. However, above 323.2 K, the aqueous acetic acid solution, of which the mole fraction of acetic acid was 0.544, was the best solvent for 1,3-benzenedicarboxylic acid. A simple explanation was given for this “maximum-solubility effect”. The present results were compared with the data obtained from our previous work. The experimental solubilities had been correlated with the Buchowski equation, and the calculated results showed good agreement with the experimental solubilities.

Solubility of 1-Hydroxyethane-1,1-diphosphonic Acid Monohydrate in Aqueous Acetic Acid Mixtures

The solubility of 1-hydroxyethane-1,1-diphosphonic acid (HEDP) monohydrate (A) in binary acetic acid (B) + water (C) solvent mixtures was measured by using the isothermal method from (293.15 to 328.15) K. A laser monitoring observation technique was employed to determine the dissolution of the solid phase in a solid + liquid mixture. The solubility data were correlated by the combined nearly ideal binary solvent (CNIBS)/Redlich−Kister equation.

Solubility of 1,2,4-Benzenetricarboxylic Acid in Acetic Acid + Water Solvent Mixtures

Using the static analytical method, the solubility of 1,2,4-benzenetricarboxylic acid in binary acetic acid + water solvent mixtures has been measured. The experimental temperatures range from (313.2 to 363.2) K, and the mole fractions of acetic acid in the solvent mixtures range from 0.416 to 1.000. The experimental solubilities were correlated by the Apelblat equation.

Solubility of N-Hydroxyphthalimide in Binary Acetic Acid + Water Solvent Mixtures at (293.2 to 363.2) K

Experimental solubilities are reported for N-hydroxyphthalimide (NHPI) dissolved in binary acetic acid + water solvent mixtures in the temperature range of (293.2 to 363.2) K. The mole fraction of water in the solvent mixtures xwater ranges from 0 to 0.5882. The experimental results show that the solubility of NHPI in the range of 10-2 to 10-3 mole fraction increases significantly with an increase in temperature and xwater. The solubility data were correlated by a modified Buchowski equation, and the parameters h and λ were regressed, which gave good agreement with all experimental data.

Solubility of terephthalic acid in aqueous acetic acid from 423.15 to 513.15 K

Using the steady-state method, the solubilities of terephthalic acid(1) in binary acetic acid(2) + water(3) solvent mixtures in a specially contrived vessel have been measured as a function of temperature in the temperature range 423.15–513.15 K and solvent composition range from x 2 = 1.000 to 0.3103 (molar fraction). The experimental solubilities are correlated with the Apelblat equation. The calculated results show good agreement with the experimental solubilities.

Solid−Liquid Equilibria of 1,4-Benzenedicarboxylic Acid in Binary Acetic Acid + Water Solvent Mixtures at Elevated Temperatures

Solid−Liquid Equilibria of 1,4-Benzenedicarboxylic Acid in Binary Acetic Acid + Water Solvent Mixtures at Elevated Temperatures

Solid−Liquid Equilibria of 1,4-Benzenedicarboxylic Acid in Binary Acetic Acid + Water Solvent Mixtures at Elevated Temperatures

The solubilities of 1,4-benzenedicarboxylic acid in binary acetic acid (2) + water solvent mixtures were measured in a specially contrived vessel in the temperature range from (433.2 to 513.2) K and solvent composition range from (w2 = 0.6 to 1.0) by the steady-state method. Results of these measurements were correlated by a modified Buchowski equation. For the five groups of data studied, the modified Buchowski equation was found to provide an accurate mathematical representation of the experimental data.

Removal of Acetic Acid by Adsorption from an Ethylene Recycle Stream in the Ethylene–Vinyl Acetate Copolymerization Process

The quality of EVA copolymers (ethylene and vinyl acetate copolymers) depends on the impurities in the feed. The removal of acetic acid, formed due to the partial degradation of the EVA copolymer, by adsorption from the recycle ethylene stream has been studied. Activated carbon proved to be useful for this purpose due to its high adsorption capacity and selectivity to acetic acid and its easy and complete regeneration. Adsorption isotherms and breakthrough curves of ethylene, acetic acid, and vinyl acetate, and binary acetic acid–vinyl acetate mixtures have been obtained at 293 K. Mass transfer and pore diffusion coefficients have been determined using two adsorption models. These data have allowed the design of an adsorption installation for the improvement of quality of EVA copolymer.