| Antimony oxychlorides Sb^Ch and SbOCl are a kind of inorganic flame retardants with high efficient retardancy. The acidic hydrometallurgy technology of antimony is a new process for treating complex antimony ores or concentrates and fine processing the antimony products. By using intermediate products in the acidic hydrometallurgy of antimony as raw materials, the new processes for preparing Sb^sClj and SbOCl flame retardants were developed in the doctorial thesis. The flame retardancy and flame retardant mechanisms were studied systematically in the thesis. The flame retardant application foundation of Sb*O jC^ and SbOCl were laid for their wide use in the future.The process for producing flame retarding Sb^sCb directly from the chlorination-leaching solution of jamesonite concentrate was first studied in this paper. After reduction, the chlorination-leaching solution was hydrolyzed by water. The impurities of the hydrolysate were removed by treating with the mixture solutions. The product of flame retarding Sb4O5Cl2 was obtained with high purity(99.85%), high whiteness(96.6), good light stability, sheet shape and average of 4.35 urn. the various impurities in the reduction solution not only affected on the hydrolysis process of SbClj, but also disturbed the forming process of Sb^sCb crystal, changed the shape of Sb4O5Cl2 crystal.The flame retarding SbOCl was first synthesized directly from the rude Sb^sCK, an intermiediate product of the acidic hydrometallurgy of antimony, in a low acidity system at low temperature and a high acidity system at high temperature, respectively. The rude Sb^Cli powder reacted with its saturated solution of concentration hydrochloric acid and SbOCl was formed when the reaction time is more than 18h, agitation velocity more than 40r/s , P (Sb3+)^290g.r' and cCH^S.lmoLL"1. the product SbOCl is cubic shape with high purity(99.80%), high whiteness(96.6), and average size of 5.90 um.In order to increase the acidity, HC1 gas was bubbled into the reacting solution which had been saturated with SbjOsCb- The rude Sb^sCh powder was added after bubbled and SbOCl was synthesized directly when P (Sb^^SSOg-L"1, c(H+)^9.70mol.L"1, T=100-11(TC. The product is very pure(99.70%) with high whiteness(93.0), average size of 10.30 um and cubic shape. The recovery rate was 70-80%.The produce costs of SbOCl with the two synthesis methods were much lower than the general methods. The amount of discharge chlorine in the acidic hydrometallurgy of antimony would be reduced, and it was also good to environmentThe studies of flame applications indicated that the prepared Sb^sCI? and SbOCl had excellent flame retardancy. When cooperated with C1(PVC) and Br(DBDPO) compounds in different polymers, the flame retardant synergetic effects of the two are greater than ultra-fine SbiO.^, and SbOCl is the best The additive mass would reduce about 16.0% and 2.0% in contrast with ultra-fine Sb^Oa in condition of the same oxygen index when cooperated with chlorine. When added to the soft PVC as the flame retardant the heat releasing rate(HRR) sequence of the flame retardant materials from high to low is, soft PVC?soft PVC containing ultra-fine St^Os梥oft PVC containing Sb4O5Cl2 -籹oft PVC containing SbOCl.The studies also indicated that the transparency ratios of the polymers containing antimony oxychlorides are higer than that containing tiny StbOj, and the dosage of coloring matters is reducedmarkedly. In same granularity, the transparency ratios of PVC films containing SbOCI and Sb^jCl? were 2.08 and 1 .39 times of that containing tiny SbjOj. In same tinting degree, the dosages of coloring matters in different polymers containing SbOCI and Sb4O5Cl2 reduced 42-65% and 30-56% respectively.The refractive indexes of SbOCI and ShjOsClj crystals were mensurated as 1.69 and 1 .74, which explained their good transparency ratio and tinting capability when used in polymers. When using SbOCI and Sb^Ch for substitute of the ultra-fine ShbOs in 70"C insulating and flame retarding cable materials, all the i...
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