| Aiming to various antimonial waste material of the smelting system output can not be recycled and damage to the environment at the same time, through analysis of the points of antimony slag of copper anode mud property, this paper suggests new technology of ‘Sodium sulphide alkaline leaching-Antimony oxide precipitates-refining and excepting miscellaneous’ sodium antimonate production. It finds a new route for antimony resources recycling and provides meaningful reference for the actual production process. This paper researches on the preparation process and the of dynamics Sodium sulphide alkaline leaching and air catalytic antimony slag sulfur oxide generation antimonous sodium antimonate sodium acid. the following conclusions was obtained:(1)Experimenting on antimony slag using Na2 S + Na OH alkaline leaching, and investigating the effect of various factors on the leaching process of antimony, we determines the optimum conditions for leaching: 165 g·L-1 sodium sulfide concentration, 30 to 40 g·L-1 sodium hydroxide concentration, solid-liquid ratio 1:5, leaching temperature 85℃ to 90℃, reaction time is 1-1.5 hours. testing in that conditions, the antimony leaching rate > 95%, the leaching residue containing antimony < 6%. Pb, Cu, Ag, Fe and other metal into the slag rate > 97%. Antimony and other metal separation as well as metal impurity elements is enriched effectively.(2)By studying the alkali leaching process of antimony slag dynamics we find that, in 55℃-85 ℃ temperature range, the leaching process belongs to chemical reaction control, temperature has a significant effect on leaching rate, and reaction apparent activation energy is 47.86 k J· mol- 1.(3)Through studying the experiment of leach liquor preparing crude sodium antimonate by air catalytic oxidation, we determines the best conditions in antimony oxide, that is 0.75 g·L-1for the amount of potassium permanganate catechol, addition amount not exceeding 0.5 g·L-1, blast strength1.415 m3·m-2·min-1, sodium hydroxide excessive coefficient 1.5 to 1.6, the reaction temperature 75℃-85 ℃, oxidation time 6 to 8 h. The oxidation of antimony rate of more than 98.06%, and the antimony concentration is less than 0.3 g·L-1 after precipitation.(4)In dynamics research of sulfur oxide generation antimonous acid sodium. by the way of isolation and half-life method dealing with the data of the experiment, the kinetics equation and activation energy of the reaction can also be obtained. Under the condition of catalytic reaction kinetics equation is:1.1610.4889Sb]×k=[Na OH][ ×dtd[Sb]-The response of the apparent activation energy for Ea = 5.04 k J ·mol-1, which determines the reaction step is diffusion and mass transfer control.(5) Low content of impurities and high whiteness sodium antimonate quality products could be gotten by removing impurity and refining crude antimony in sodium acid soluble. SEM analysis showed that sodium antimonate even distuibuted sizes, good dispersion, large particle size, the average grain size of 80 microns. Antimony total recovery > 91.23%... |
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