西藏硼镁矿制取硼酸联产碳酸镁工艺研究

提出了西藏硼镁矿综合利用的新工艺，即用硫酸铵复分解法分解西藏硼镁矿制取硼酸和碳酸镁。考察了反应温度、反应时间、硫酸铵的初始浓度、硫酸铵的用量比等工艺条件对硼浸出率的影响。较佳工艺条件为：反应温度100 ℃、反应时间2~2.5 h、硫酸铵的初始浓度为9%~11%（质量分数）、硫酸铵的用量为理论量的110%。在此工艺条件下，硼酸的收率可达95%，碳酸镁的收率可达90%以上。该工艺充分利用了西藏硼镁矿的硼、镁资源，提高了硼的收率。

Study on preparation of boric acid and magnesium carbonate from Tibetan szaibelyite

A new technique is proposed for multi-purpose utilization of Tibetan szaibelyite by metathetical reaction with ammonium sulfate to prepare boric acid and magnesium carbonate.Effects of technique conditions,such as reaction temperature,reaction time,initial concentration of ammonium sulfate,and proportion of ammonium sulfate to its stoichiometry,on the leaching rate of boron were investigated.The optimum process conditions were as follows,reaction temperature was 100 ℃,reaction time was at 2.0~2.5 h,initial concentration of ammonium sulfate was at 9%~11 %(mass fraction),and the proportion of ammonium sulfate to its stoichiometry was 110%.The yields of boric acid and magnesium carbonate could reach over 95% and 90%,respectively.The technique is favorable to making full use of the boron and magnesium in Tibe-tan szaibelyite and increasing the yield of boron.