含硫铝酸钠溶液中铁质量浓度的变化规律

Variation of mass concentration of iron in sulfur sodium aluminate solution

在260℃高压溶出黄铁矿制备高硫高铁的铝酸钠溶液,研究溶液温度、保温时间、苛性比（αk）以及Na_2CO_3,Na_2SO_4和Na_2C_2O_4等杂质对溶出液中铁质量浓度的影响。研究结果表明：溶液温度为50℃和60℃时,随着保温时间的延长,溶液中铁质量浓度略有降低;苛性比为3.0左右时,随着Na_2CO_3质量浓度的升高,溶液中铁质量浓度略有升高,而Na_2SO_4和Na_2C_2O_4质量浓度的升高则能显著提高溶液中的铁质量浓度;随着溶液苛性比的升高,溶液中铁质量浓度在苛性比为2.0~2.5之间有1个急剧升高的区间,然后逐渐趋于稳定。

The sodium aluminate solution with high iron and sulfur content was prepared by the high-pressure digestion of pyrite at 260 ℃. The influences of temperature, residence time, caustic ratio αk and the content of Na_2CO_3, Na_2SO_4 and Na_2C_2O_4 on the mass concentration of iron in sodium aluminate solution were investigated. The results show that the mass concentration of iron decreases slightly with the increase of residence time when the solution temperatures are 50 ℃and 60 ℃. When αk is approximately 3.0, the mass concentration of iron increases slightly with the increase of Na_2CO_3 mass concentration and obviously with the increase of Na_2SO_4 and Na_2C_2O_4 concentration. The mass concentration of iron increases rapidly with αk from 2.0 to 2.5 and then enters a relatively stable state with the continuous increase of αk.