黝铜矿碱性体系制备佛酸钠的试验研究.

The alkaline extraction method is adopted to selectively extraction the antimony from the tetrahedrite in the system of sodium sulfide and sodium hydroxide. Then, high temperature and pressure oxidation precipitation was used to generate sodium antimonate from alkaline extraction solution. And the effects of alkaline extraction process parameters on the antimony extraction rate and antimony precipitation process parameters on the precipitation rate of sodium antimonate were studied respectively. The results show that the best conditions of extraction antimony from tetrahedrite at high temperature and high pressure are： extraction temperature is 150 °C, extraction time is 6 h, liquid solid ratio is 6; 1, sodium sulfide concentration is 120 g/L, sodium hydroxide concentration is 80 g/L. Under these conditions, the extraction rate of antimony reaches more than 80 %, which is much higher than that of 45 % under low temperature and ordinary pressure. The optimum reaction conditions for preparing sodium antimonate by high temperature and high pressure oxidation of tetrahedrite leaching solution are as follows: reaction time 2 h, excess coefficient of sodium hydroxide 1.6, oxygen pressure 0. 8 MPa and temperature 150 °C. With these conditions, the antimony precipitation rate can reach more than 98%. The results show that the sodium antimonate prepared by this method meets the industrial needs in terms of product quality, particle size and morphology. [ABSTRACT FROM AUTHOR]