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The analysis of sensibility of a process has been applied to numerous engineering fields like a tool for the development of mathematical models, since it allows to determine which of the different operation variables has a bigger influence on the results of interest of the process. In this work,starting from the equation of global speed of identified precipitation for the cobalt sulfide, is made an analysis that allows to obtain the indexes of sensibility with which the system responds to the changes in the work variables that have shown significant effects on the operation. [ABSTRACT FROM AUTHOR]

The precipitation of Ni and Co mixes sulphides is one of the stages of the ammoniacal technological process in the cuban nickel industry, but the oxidation of sulphides disturbs its storage and transportation. This paper exposes results from chemical characterization by X-ray diffraction and mineragraphic analysis of mixed sulphides as well as from the kinetic investigation of the thermal oxidation of samples in isothermal and no isothermal regime. It's determined de most probable model and kinetic parameters of the physical-chemical transformations that occurs in oxidation process. It's concluded that oxidation of mixed sulphide concentrate follows 4 stages: lost of water and ammonio, degradation of superior sulphides, formation of sulphates and degradation of sulphates into oxides. Degradation of sulphides into oxides degradation of sulphides to oxides Nickel and cobalt sulphides obtained through leaching technology carbonates ammoniacal of laterític ferrous nickelitic ore is characterized and is studied in the kinetics of oxidation concentrated in nickel and cobalt sulphides applying the isothermic and not isothermic methods, being determined the most probable pattern and the kinetic parameters of the physical chemical transformations that take place in the process of oxidation. [ABSTRACT FROM AUTHOR]

Studied is the efficiency of selective precipitation of cobalt from synthetic carbonate ammoniacal solutions using as precipitation agents for ammonium hydrogen sulphide and sodium hydrogen sulphide, being determined the most adequate conditions of precipitation. The analysis done permit to identify the factors that influence the development of the reactions of nickel and cobalt precipitation. Obtaining are the mathematical static models that characterize the reactions of precipitation of cobalt, and compare the precipitation influence of each precipitant agents. [ABSTRACT FROM AUTHOR]

The stage of precipitation of nickel and cobalt sulphide mixed from industrial solutions, using ammonium hydrogen sulphide as agent for precipitation, have been studied during this research. The thermodynamic analysis of the precipitation and interchange reactions, permitted us to determined the mathematical models showing the dependency existing between the constant of equilibrium and temperature. In the development of the reactions precipitation of nickel and cobalt sulphide mixed from carbonate ammoniacal solutions are influenced by the following factors: temperature, time, recirculation of sulphide and agitation. Obtaining are the mathematical statistic models that characterize the reactions of precipitation nickel and cobalt. [ABSTRACT FROM AUTHOR]