Density, ultrasonic velocity, electrical conductivity, viscisity and Raman Spectra of methanolic Mg(ClO4)2, Mg(NO3)2 and Mg(OAc)2 solutions

Density, ultrasonic velocity, electrical conductivity, viscosity, and Raman spectra of methanolic Mg(ClO4)2, Mg(NO3)2, and Mg(OAc)2 solutions were measured as functions of concentration (dilute to saturation) and temperature (273.15 e T/K e 313.15). The isentropic compressibility, electrical conductivity, and Raman spectral data reveal the following order of anion-solvent interactions and mobility in methanol: OAc- < NO3 - < ClO4 -. Anionic effect on the isentropic compressibility and conductivity roughly appear to follow Hofmeister series. Transport properties and Raman spectra also indicate a moderate solvent-shared ion pairing in concentrated Mg(NO3)2 solutions

The influence of functionality on the adsorption of p-hydroxybenzoate and phthalate at the hematite - electrolyte interface

Kinetics of adsorption of p-hydroxy benzoate and phthalate on hematite 13electrolyte interface were investigated at a constant ionic strength, I =

Kinetics and adsorption behaviour of benzoate and phthalate at the alpha-alumina- water interface : influence of functionality

Asystematicstudyonthei

Adsorption and surface complexation of trimesic acid at the alpha-Alumina electrolyte interface

Adsorption kinetics, adsorption isotherms and surface complexation of trimesic acid onto α-alumina surfaces were investigated. Adsorption kinetics of trimesic acid with an initial concentration of 0.5 mM onto α-alumina surfaces were carried out in batch method in presence of 0.05 mM NaCl(aq) at pH 6 and 298.15, 303.15 and 313.15 K. Adsorption isotherms were carried out at 298.15 K, pH 5–9, and 0.05 mMNaCl(aq) by varying trimesic acid concentration from 0.01 to 0.6 mM. Three kinetics equations such as pseudo-first-order, pseudo-second-order and Ho equations were used to estimate the kinetics parameters of the adsorption of trimesic acid on the α-alumina surfaces. Ho equation fits the experimental kinetics data significantly better and the estimated equilibrium concentration is in excellent agreement with the experimental value. The adsorption data were fitted to Freundlich and Langmuir adsorption model and the later best fits the adsorption isotherms. Comparison of adsorption density of trimesic acid with that of benzoic and phthalic acids follows the sequence: benzoic acid < trimesic acid < phthalic acid. The negative activation energy and the Gibbs free energy for adsorption indicate that the adsorption of trimesic acid onto α-alumina is spontaneous and facile. DRIFT spectroscopic studies reveal that trimesate forms outer-sphere complexes with the surface hydroxyl groups that are generated onto α-alumina surfaces in the pH range of the stud

Adsorption comparison at the á-alumina/water interface: 3,4- dihydroxybenzoic acid vs catechol

Adsorption kinetics and isotherms and the surface complexation of 3,4-dihydroxybenzoic acid (3,4DHBA) and catechol at the -alumina/electrolyte interface were investigated. The state of equilibrium for adsorption of 3,4-DHBA onto -alumina surface at pH 5 was attained at 120 min, whereas it was 90 min for catechol, but at pH 10 the state of equilibrium for the both the systems was same ( ∼60 min). The pseudo-second-order kinetic equation of nonlinear form (Eq. (3)) fits the experimental kinetic data significantly better than the linear form (Eq. (2)) in the entire time duration. The adsorption density of 3,4-DHBA onto the -alumina surfaces at pH 10 and at similar experimental conditions is equivalent to catechol. DRIFT spectra indicate that 3,4-DHBA forms both outer- and inner-sphere complexes and catechol forms bidentate mononuclear complex with the -alumina surface