氟硅酸制备白炭黑和氟化氢铵的工艺研究  

Study on Preparation Technology of Silica and Ammonium Bifluoride from Fluosilicic Acid

作　　者：周桂明[1] 郑典模[1] 李少飞[1] 胡颖进[1] 

机构地区：[1]南昌大学环境与化学工程学院,南昌330031

出　　处：《硅酸盐通报》2013年第1期30-34,共5页Bulletin of the Chinese Ceramic Society

摘　　要：研究以氟硅酸和氨水为原料,通过沉淀反应、搅拌陈化、固液分离得滤液和滤渣,滤渣经酸化、水洗、喷雾干燥等工艺过程制备白炭黑,滤液经真空法制备氟化氢铵,所得氨水作为原料返回系统循环使用。实验考察了氟硅酸与氨水滴加的体积比、底液与氨水体积比、反应温度、陈化时间等因素对白炭黑DBP值的影响,获得制备白炭黑的最佳工艺条件:氟硅酸与氨水滴加的体积比为1∶6,底液与氨水体积比为0.6,反应温度为75℃,陈化时间为6 h,此条件下得到的白炭黑DBP值为3.53 mL/g,并对其进行了FT-IR、XRD、TEM表征和粒径检测,证实产物为白炭黑,粒径(d50)235 nm。氟化氢铵经XRD和SEM表征,确定产物为氟化氢铵,纯度为98.7%。Taking fluosilicic acid and ammonia as the material, filtrate and residue were obtained via precipitation reaction, stirring aging and solid-liquid separation , filtrate was prepared to the silica by a series of processes of acidification, washing and spray drying, and residue was prepared to the ammonium bifluoride by vacuum method, the ammonia as raw material return system recycling. Several effects of reaction factors were investigated and optimum conditions were confirmed as follows： the dropwise add volume ratio of fluosilieic acid and ammonia was 1 ： 6, the volume ratio of base solution and ammonia was 0.6,reaction temperature was 75 ℃, aging time was 6 h. Under the optimum conditions, the DBP of silica was 3.53 mL/g, The product was characterized by FT-IR, XRD , TEM and particle size detection, the results showed that the product was silica , and the particle size of product was 235 nm （d50）. The ammonium bifluoride was characterized by XRD and SEM, the results confirmed that the product was ammonium bifluoride, and the purity of product was 98.7%.

关 键 词：氟硅酸 氨水 白炭黑 氟化氢铵 

分 类 号：TQ127[化学工程—无机化工]