Leaching rates of Icel-Yavca dolomite in hydrochloric acid solution


Akarsu H., YILDIRIM M.

MINERAL PROCESSING AND EXTRACTIVE METALLURGY REVIEW, cilt.29, sa.1, ss.42-56, 2008 (SCI-Expanded) identifier identifier

Özet

Experiments were performed in aqueous hydrochloric acide (HCl) solutions over the bulk solution pH -0.01 to 0.71 and at temperatures of 25, 40, 50, 70, and 85 degrees C. Variation of the dissolution recoveries, temperature, and pH with the time were studied. The logarithms of the chemical dissolution rates (r) obtained at constant hydrodynamic conditions for various temperatures and pH were consistent with r = k(1)a(H)(,)(+) (bulk), where k(1) stands for the chemical rate constant and a(H)(,)(+) (bulk), designates the hydrogen ion activity in the bulk solution. The overall dissolution rate constants were obtained by plotting the R values calculated by using the (Ca2+, Mg2+) concentrations measured against the time. The overall dissolution rate constant obtained was inconsistent with the corresponding rate constants in the literature reported by Letterman (1995). The apparent activation energy obtained over the temperatures 25 to 85 degrees C was 0.13 kJ.mol(-1).

Experiments were performed in aqueous hydrochloric acide (HCl)

solutions over the bulk solution pH

 

0.01 to 0.71 and at temperatures

of 25, 40, 50, 70, and 85C. Variation of the dissolution recoveries,

temperature, and pH with the time were studied. The

logarithms of the chemical dissolution rates (r) obtained at constant

hydrodynamic conditions for various temperatures and pH were

consistent with r

 

¼ k1aH

ş

,bulk

 

, where k1 stands for the chemical rate

constant and a

 

H

ş

,bulk

 

, designates the hydrogen ion activity in the

bulk solution. The overall dissolution rate constants were obtained

by plotting the R values calculated by using the (Ca

 

2ş, Mg2ş) concentrations

measured against the time. The overall dissolution rate

constant obtained was inconsistent with the corresponding rate constants

in the literature reported by Letterman (1995). The apparent

activation energy obtained over the temperatures 25 to 85C was

0.13 kJ

 

 mol