氟硅酸铵制备氟化钾联产白炭黑的实验研究

以磷肥副产的氟硅酸铵和氢氧化钾为原料,采用一步法制备氟化钾联产白炭黑。探讨主要因素对KF收率和KF纯度的影响,确定适宜的工艺条件为:反应温度82℃,w((NH_4)_2SiF_6)22%,w(KOH)40%,n(KOH)/n((NH_4)_2SiF_6)6.2;在配料比分别为6.2和6.1条件下,考查白炭黑洗涤水多次循环利用对氟化钾纯度、收率等的影响,综合考虑各项指标,最终确定配料比为6.2;在适宜工艺条件下产品各项指标均已达到HG/T 2829—2008、HG/T 3061—2009合格品的要求,且氟化钾产品收率可达94%以上。

Study on preparation of potassium fluoride and silica from ammonium fluorosilicate

Using ammonium fluorosilicate,a phosphate fertilizer by-product,and potassium hydroxide as raw materials,potassium fluoride and silica are prepared through a one-step method.The influences of the main factors on yield of potassium fluoride and purity of potassium fluoride are discussed.The optimum technological conditions are as follows:reaction temperature of 82 ℃,concentration of ammonium fluorosilicate of 22％,concentration of potassium hydroxide of 40％,mole ratio of materials being 6.2,under the conditions of mole ratio of 6.2 and 6.1 respectively,the effects of multiple recycling on the purity and yield of potassium fluoride are discussed.Considering the various indicators,the optimum mole ratio of materials is chosen as 6.2.Under the appropriate technological conditions,the qualification for products prepared can meet the requirements of HG/T 2829-2008 and HG/T 3061-2009,and the yield of potassium fluoride products can reach above 94％.