石蜡乳液中直接沉淀制备单分散性的纳米氧化镁

摘要

MgO nanoparticles were prepared by using a direct deposition method, in which, the precursor, alkaline magnesium carbonate/paraffin, was firstly obtained by direct precipitation of the mixture of MgCl2·6H2O and Na2CO3 in paraffin emulsion, and then calcined at 600℃. The nanoparticles were characterized by using TG-DTA, FTIR, XRD, BET and FESEM. Under the optimum conditions, the as-prepared MgO nanoparticles were hexagonal crystals with a uniform size of around 60 nm and a specific surface area of 132.54 m2·g−1. The optimum preparation conditions were: MgCl2·6H2O concentration, 0.6 mol·L−1; Na2CO3 concentration, 0.6 mol·L−1;reaction time, 0.5 h;calcination temperature, 600℃, and calcination time, 3 h.%MgCl2·6H2O和 Na2CO3在石蜡乳液中直接沉淀出碱式碳酸镁/石蜡前驱体，该前驱体在600℃条件下焙烧后获得MgO纳米粉体。采用TG-DTA、FTIR、XRD、BET和FESEM等手段对MgO粉体进行表征分析，并研究焙烧温度和物料比对纳米 MgO 的粒径及形貌的影响。结果表明，在最佳工艺条件下，石蜡乳液体系中能够得到分散性好、晶粒呈六边形、颗粒均匀、平均粒径约60 nm和比表面积132.54 m2·g−1的纳米MgO。其最佳工艺条件为：MgCl2·6H2O溶液浓度0.6 mol·L−1、Na2CO3溶液浓度0.6 mol·L−1、反应时间0.5 h、焙烧温度600℃和焙烧时间3h。