Nb_2O_5粒度的工艺控制研究

Research on Process Control of Nb_2O_5 Particle Size

采用分步沉淀法将铌液沉淀生成Nb（OH）_5,经洗涤、烘干、煅烧获得Nb_2O_5产品,研究了Nb_2O_5粒度的工艺控制条件。结果表明,在料液中先通入0.1MPa的氨气,中和料液pH值至4,自然冷却16h后快速通入0.3MPa氨气直至反应完成（沉淀终点料液pH控制为9）,产物经洗净、240℃烘干6h、860℃煅烧后,即可得到平均粒径（D50）为1~5μm的Nb_2O_5产品。当铌液的浓度增大到一定范围时,最终煅烧出的Nb_2O_5平均粒径增大;煅烧炉温升高,煅烧出的Nb_2O_5平均粒径也增大。

Nb（OH）5 was obtained from niobium liquid by fractional precipitation, and then Nb2O5product was prepared by washing, drying and calcination. Process control conditions ofNb2O5particle size were studied. The results show that the obtained Nb2O5 product has average particle size （D50） of 1-5 μm by the process as follows：bubbling 0.1 MPa ammonia into the feed liquid, neutralizing niobium liquid pH to 4,natural cooling for 16 h,quickly bubbling 0.3 MPa ammonia to complete reaction （precipitation end pH = 9） ,washing,drying at 240 ℃ for 6 h and calcination at 860 ℃. When niobium liquid concentration increa- ses to a certain range, the final Nb2O5product has increased average particle size. With increased calcination furnace temperature,the average particle size of the calcined Nb2O5 product increases.