【摘要】 采用稀土含量0.55%REO磷矿为原料在间歇实验装置中进行二水物湿法磷酸模拟生产,研究了湿法磷酸生产中工艺条件及活性添加剂对磷矿中稀土走向的影响。研究结果表明:较低的体系温度、高的磷酸浓度及较大的液固比均有利于稀土在磷酸中的富集;控制合适的SO24-浓度有利于硫酸钙晶体的成长,可减少磷酸稀土的共晶和吸附作用,从而提高稀土的浸出率,在硫酸与磷矿的化学计量比为1.1时可形成易于洗涤和过滤的类球状聚晶;通过添加活性添加剂控制硫酸钙的结晶速度和结晶形貌,从而减少磷酸稀土和硫酸钙的共晶和吸附作用,以提高稀土在磷酸中的富集;添加不同活性添加剂,稀土在磷酸中的富集程度不同,其中以NS-2,NS-1及IA-1对稀土在磷酸中的富集影响尤著,稀土总浸出率可达75%以上。更多还原

【Abstract】 The wet phosphoric acid production process was simulated in the batch reactor with phosphorite concentrate containing 0.55% REO.The effect of process factors and active additives on the distribution of RE during the wet-process of phosphoric acid production was studied.The results indicated that it was beneficial for the RE enrichment in phosphoric acid with lower temperature,higher concentration of phosphoric acid and larger ratio of liquid to solid.It was also benefit for gypsum crystal growing with appropriate SO2-4 concentration which could decrease the eutectic and sorption of RE phosphate,so as to increase the RE leaching rate.When the stoichiometric ratio of sulfuric acid and phosphate was up to 1.1,the calcium sulfate formed as spherical polycrystalline which was easy to be filtered and scrubbed.The rate and shape of crystal of calcium sulfate could be controlled with active additives,so as to decrease the eutectic of rare earth phosphate and sorption of calcium sulfate.The effect of different active additives on the enrichment of the rare earth in wet-process phosphoric acid was different and the leaching rate of rare earth was more than 75% with NS-2,NS-1 and IA-1.更多还原