Optimization of Processing Conditions for the Preparation of Cubic Nano-sized Calcium Carbonate by Intermittent Bubbling Carbonation
[Objective] The optimal process conditions were explored for preparing cubic nanosized calcium carbonate with uniform morphology and narrow particle size distribution.[Methods]An improved intermittent bubbling carbonization method was adopted to synthesize cubic nano-sized calcium carbonate.Many significant operational conditions were investigated,including carbonation temperature,the initial concentration of calcium hydroxide,the injection flow rate of carbon dioxide,sodium hexametaphosphate addictive and the stirring rate which have important effects on the particle size and reaction time.In addition,size distribution,field emission scanning electron microscopy and X-ray diffraction were applied to characterize the particle.[Results]The optimum conditions were as follows:The carbonization temperature was 10℃,the initial Ca (OH)2 concentration was 3.8％(W/W),the flow rate of CO2 was 300 mL · min-1,2％ sodium hexametaphosphate was added after 5 min of reaction time,and the stirring rate was 800 r · min-1.The cubic nanosized calcium carbonate was obtained with an average particle size of 40 nm.XRD results showed that the cubic nano-sized calcium carbonate was identified as calcite with hexagonal structure.[Conclusion]This method is simple with a stable and reliable quality of product.Moreover,there is no need for the secondary carbonation.Thus the research has a great significance to industrial production.
国家科技期刊平台
NSTL
万方数据
维普
