(中南大学 冶金与环境学院，长沙 410083)
摘 要: 总结焦锑酸钠传统处理方法的优缺点，计算并绘制不同温度下Sb-H2O系φ-pH图。结果表明：在高温高压下可以用氧气将不同形式的Sb3+氧化为Sb5+，提出在3种不同体系中采用加压氧化方式制备焦锑酸钠的清洁生产工艺。首先，用氧气加压氧化硫代亚锑酸钠得到焦锑酸钠产品，锑的沉淀率达到99.80%，与空气氧化法相比，加压氧化法大幅度缩短了氧化时间。其次，在KOH体系加压氧化溶解锑白，焦锑酸钾溶液加入NaOH沉淀产出焦锑酸钠产品，加压氧化过程锑白完全溶解，产品中几乎不含Sb3+。再次，在NaOH体系锑白直接加压氧化产出焦锑酸钠，但焦锑酸钠产物中Sb3+含量仍在1.0%左右。最后，在NaOH体系锑白配合溶解，亚锑酸钠溶液经过加压氧化产出合格焦锑酸钠产品，锑的沉淀率达到97.70%。这两个体系用氧气加压氧化代替传统的H2O2，降低了成本。加压氧化法为焦锑酸钠的清洁生产工艺发展提供了一种新的思路。
关键字: 锑；加压氧化；浸出；沉淀
（School of Metallurgy and Environment, Central South University, Changsha 410083, China）
Abstract:The advantages and disadvantages of the traditional treatment methods of sodium pyroantimonate were summarized, and the φ-pH diagram of the Sb-H2O system at different temperatures was calculated and drawn. The result shows that the φ-pH diagrams of Sb-H2O system at different temperatures indicate that Sb3+ can be oxidized into Sb5+ with oxygen gas at high temperature and high pressure. Therefore, a series of clean technologies for producing sodium pyroantimonate by pressure oxidation in three different solutions were proposed. Firstly, sodium thioantimonite is oxidized with oxygen gas at high pressure to get the sodium pyroantimonate product, the precipitation ratio of antimony can reach 99.80%. And the reaction time of pressure oxidation is greatly reduced compared to that by air oxidation method. Secondly, Sb2O3 is dissolved in KOH solution by pressure oxidation to obtain a KSb(OH)6 solution, then NaOH is added into to prepare sodium pyroantimonate. Sb2O3 is completely dissolved during the pressurized oxidation process, and the product contains almost no Sb3+. Thirdly, sodium pyroantimonate can be directly prepared from Sb2O3 by pressure oxidation in NaOH system, but the Sb3+ content in this product is still among 1.0%. At last, Sb2O3 is dissolved in NaOH solution to get NaSb(OH)4 solution, and then qualified sodium pyroantimonate can be prepared from NaSb(OH)4 solution by pressure oxidation. The precipitation ratio of antimony reaches 97.70%. The pressure oxidation with oxygen gas in these two systems is used instead of the conventional agent of hydrogen peroxide, which has low cost. The pressure oxidation method provides a new idea to the development of clean production process for producing sodium pyroantimonate.
Key words: antimony; pressure oxidation; leaching; precipitation
