钾长石-磷矿-硝酸脲体系分解钾长石的探讨

详细研究了钾长石与磷矿、硝酸脲反应的提钾新工艺， 验证了钾长石-磷矿-硝酸脲体系分解钾长石提取有效钾的可行性。通过正交实验得到各因素对钾溶出率影响大小依次为：反应温度>硝酸用量>反应时间>尿素与硝酸物质的量比。得到适宜的工艺条件：尿素和硝酸物质的量比为1:1；5.5 mol/L的硝酸用量为4 mL；反应温度为120 ℃；反应时间为2 h。在此条件下有效钾的溶出率可达96.23%，水溶性钾溶出率可达29.65%。通过单因素寻优实验得出钾长石与磷矿、硝酸脲反应提取有效钾的适宜工艺条件：反应温度为105～115 ℃，硝酸用量约为4.7 mL，反应时间约为2 h。

Study on extraction of potassium feldspar from potassium feldspar-phosphate rock-urea nitrate system

New technology of refining potassium from the potassium feldspar-phosphate rock-urea nitrate system was studied in detail，the feasibility of this system to resolve potassium feldspar extracting effective potassium was validated.The orthogonal experiment results showed that the sequence of factors which affected potassium extraction ratio was: reaction temperature>dosage of nitric acid>reaction time>the amount-of-substance ratio of urea to nitric acid.The suitable technology conditions were obtained as follows：the amount-of-substance ratio of urea to nitric acid was 1∶1，nitric acid（5.5 mol/L） dosage was 4 mL，reaction temperature was 120 ℃，and reaction time was 2 h.Under those conditions，the effective potassium extraction rate could be up to 96.23%，and water-soluble potassium extraction rate reached 29.65%.The suitable technology conditions through the optimization of single factor experiments were as follows: reaction temperature was at 105～115 ℃， dosage of nitric acid was about 4.7 mL，and reaction time was about 2 h.