The kinetics of aluminum
leaching from sludge solid waste (SSW) using hydrochloric acid at different
leaching temperatures (30-90°C) was studied. A mathematical model was developed based on a
shrinking core model by assuming first-order kinetics mechanisms for leaching
and an equilibrium linear at the solid-liquid
interface. The proposed model is suited to fit experimental data with three
fitting parameters and to simulate the leaching of aluminum from SSW, which was
validated with the mass transfer coefficient (kc, cm/s),
diffusion coefficient (De,
cm2/s), and reaction rate constants (k, cm/s). The evaluated kc,
De, and k are expected to follow an increasing
trend with increasing temperature. The correlation coefficient ≥ 0.9795, the
root mean square error ≤ 0.399, the mean relative deviation modulus ≤ 6.415%,
and the value of activation energy is 13.27 kJmol-1. The proposed model could describe the kinetics of
aluminum leaching from the SSW DWT in accordance with test parameters and
relevant statistical criteria. Valuable information on the results of this work
can be given for the purposes of the simulation, optimization, scaling-up, and
design of the leaching
process.
