摘要
以水氯镁石和氨气为原料,在不加入任何添加剂的条件下,利用直接沉淀法,制备具有高料浆质量分数的氢氧化镁阻燃剂。研究了搅拌强度、氨镁摩尔比、氨气加入流量、陈化时间、反应温度、氯化镁浓度对制备氢氧化镁粒度分布以及料浆浓度的影响,确定了最佳工艺条件:搅拌强度350 r/min、氨镁摩尔比2∶1、氨气加入流量320 mL/min、陈化时间90 min、反应温度60℃、氯化镁浓度4.30 mol/L。用扫描电子显微镜、X射线衍射仪和激光粒度分布仪表征产品的形貌、结构及粒度。在最佳工艺条件下制备得到的氢氧化镁D501.43μm,D902.40μm,料浆质量分数12.26%,Mg收率69.41%,氢氧化镁纯度99.60%,白度99.34。
Magnesium hydroxide of high mass fraction slurry was directly synthesized without any additives,using bischofite and ammonia as raw materials.Stirring speed,mole ratio of ammonia to magnesium,ammonia gas addition rate,ageing time reaction temperature and magnesium chloride concentration were studied to find their influences to magnesium hydroxide slurry concentration and particle size.The optimum processing conditions were obtained as follows：stirring speed 350 r/min,mole ratio of ammonia to magnesium 2∶1 ,ammonia addition rate 320 mL/min,aging time 90 min,reaction temperature 60 ℃ and magnesium chloride concentration 4.30 mol/L.The effects of characterize product morphologies, structures and size distributions involved were studied through scanning electron microscope,X-ray diffractometer and laser particle analyzer.The magnesium hydroxide obtained under the optimal reaction conditions had D50 of 1 .43 μm,D90 of 2.40 μm,purity of 99.60% and whiteness of 99.34.The reaction yield reached 69.41% with magnesium hydroxide slurry mass fraction of 1 2.26%.
出处
《化学工程》
CAS
CSCD
北大核心
2014年第6期74-78,共5页
Chemical Engineering(China)
基金
科技部科技支撑计划项目(2009BAE83B02)
青海省科技厅基金项目(2010-G-221A)
西部之光项目(2011-1)
关键词
氢氧化镁
氨气法
氯化镁
高质量分数料浆
magnesium hydroxide
ammonia gas method
magnesium chloride
high mass fraction slurry
作者简介
宋雪雪（1988-），女，硕士研究生，主要从事新型无机材料研究；
李丽娟（1962-），女，研究员，通信联系人，E-mail：lilj180508@gmail．com。
