A Semiempirical Kinetic Model for Dissolution of Colemanite in Aqueous CH₃COOH Solutions

Abstract

In this study the dissolution of Colemanite in aqueous acetic acid solutions was investigated in a batch reactor employing the parameters of particle size, solid-to-liquid ratio, and temperature. It was found that the dissolution rate increases with increasing temperature and decreasing solid-to-liquid ratio and particle size. The most effective parameter was particle size with a power of −1.420 after temperature and solid-to-liquid had less effect than the other parameters. The conversion rate increased up to 3.365 M acid concentration and then decreased with increasing acid concentration. No important effect of stirring speed was observed. The activation energy of the process was determined to be 51.490 kJ mol-1. It was determined by graphical and statistical methods that the reaction fits a model in the form of −ln(1 − X) = kt. The following semiempirical mathematical model, which expresses the process well, was established: −ln(1 − X) = 56 664(D)-1.42(S/L)-0.270 exp(−6193.0/T)t, where X is the conversion fraction, D the particle size, S/L, the solid-to-liquid ratio, and T the reaction temperature.

Production of crystalline boric acid and sodium citrate from borax decahydrate

“…(6)) (Alkan and Dogan, 2004;ZareNezhad, 2003), acetic acid (Eq. (7)) (Ekmekyapar et al, 2008;Ozmetin et al, 1996) and citric acid (Eq. (8)) (Ciftci, 2012), was investigated in terms of their B 2 O 3 extraction conditions.…”

Kinetics of sulfuric acid leaching of cadmium from Cd–Ni zinc plant residues

“…Concerning metal species in elemental form, during leaching experiments oxidation occurs to the divalent state according to reactions (5)- (9) and therefore the solubilization conditions can be predicted from relevant E h -pH diagrams, as presented in …”

“…This behavior could be explained by the fact that as the acid concentration in the medium increases, the apparent rate of product increases and as the product reaches the saturation value near the solid particle; it forms a difficult soluble solid film layer around the particle. Consequently, the dissolution process slows down [9].…”

Investigation of Leaching Kinetics of Ulexite Waste in Oxalic Acid Solutions

“…Filtration of calcium salts from pregnant solution has an important role in the production of boric acid, since these salts reduce the quality of the boric acid produced and generate environmental pollution. 6,16 Bayca reported that boric acid is currently produced in Turkey by the acid leaching process. In this process, colemanite concentrate is leached with a hot sulfuric acid solution, the result being calcium ions.…”