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This research is a proposal for replacing carbonated silt used as neutralizing agent in acid leaching technology with residual dust from marble industry. The liquor neutralization process in pressure acid leaching contains sulfuric acid concentration to excess with pH values equal to 1.9 units, which allows using solid calcium carbonate residues from marble industry. The research was carried out at laboratory scale with an agitation regime of 68 rpm. The multilevel factorial design was used, where two factors are studied: solid mass of neutralizing agent (1, 2, 3 and 4 g) and temperature (50 °C and 700 °C. Behavior of variables was also assessed by means of kinetic model. The statistical models showed a direct relationship between the increase of solid in the mass and the temperature, where the first factor exerts a positive influence on the process. The best pH results are obtained in test 1, for (50 °C and 1 g), where values from 2.37 to 2.53 are achieved between one to ten minutes. [ABSTRACT FROM AUTHOR]