Density, Viscosity, and Surface Tension of Aqueous Solutions of Potassium Glycinate + Piperazine in the Range of (288.15 to 323.15) K

Abstract

Densities and viscosities of aqueous solutions of potassium glycinate (PG) þ piperazine (PZ) composed of x PG /x PZ (mol/mol) = 1.0/0, 0.9/0.1, 0.8/0.2, 0.7/0.3, and 0.6/0.4 have been measured at (288.15, 303.15, 313.15, and 323.15) K. Surface tensions of aqueous solutions of (PG þ PZ) have been determined at 288.15 K. Correlations by means of mathematical fitting were developed for the predictions of density, viscosity, and surface tension of the aqueous solutions of (PG þ PZ) using the experimental data of this work. Results show that the densities and viscosities decrease as the temperature increases. The densities of the studied solutions decrease with the increase of PZ mole fraction in the solutions, while viscosities of the solutions increase. The surface tensions of the solutions almost decrease linearly as the PZ mole fraction in the solution increases from 0 to 0.4. The prediction values from correlation equations for density, viscosity, and surface tension are in good agreement with the experimental values. The correlation equations for each property can offer additional data for aqueous solutions of (PG þ PZ).

Density, Viscosity and Excess Molar Volume of the Aqueous Ionic Liquid Tris(monoethanolamine) Citrate at 293.15–323.15 K

“…Validation details can be also found in our previous work [30,31]. Results of validation in this work using glycol and glycerol at 295.15 K are shown in Table 2.…”

“…Reported results are the average values of five samples. Experiments were carried out by the following procedures [30,31]. (1) Determining the volume of the pycnometer: first, determine the mass of the empty dry pycnometer.…”

“…The temperature control system was the same as that for the density measurements. The flow times of samples were recorded using a stopwatch with accuracy ±0.01 s. Experiments were carried out as follows [30,31]. The viscometer was cleaned with 15 % H 2 O 2 and 15 % HCl before use.…”

Measurement and prediction of densities, viscosities, and surface tensions for aqueous solutions of potassium citrate

“…It can be found that, as expected, the viscosities of the aqueous PC solutions decrease with the increase of temperature, and increase as the molar concentration of aqueous PC solution increases. Compared with aqueous amino acid salt such as potassium glycinate and potassium taurate, the viscosities of aqueous potassium citrate are larger than that of aqueous potassium glycinate and potassium taurate under the same conditions of concentration and temperature [12,14]. This is because of molecular weight of the potassium citrate is higher than that of them.…”

“…The density, viscosity and surface tension of aqueous amino acid salts can also be obtained from the literature [12][13][14] Then the solution was transferred into a 50 mL standard flask and deionized water was added into the flask to the mark. The potassium citrate solution was prepared in a 50 mL standard flask to a given concentration.…”