Shirsath S R, Sonawane S H, Saini D R, Pandit A B
Department of Chemical Engineering, Vishwakarma Institute of Technology, 666 Upper Indira Nagar, Pune 411037, India.
Department of Chemical Engineering, National Institute of Technology, Warangal, AP 506004, India.
Ultrason Sonochem. 2015 May;24:132-9. doi: 10.1016/j.ultsonch.2014.12.003. Epub 2014 Dec 13.
The continuous production of calcium carbonate (CaCO3) by precipitation method at room temperature was carried out in a stirred reactor under ultrasonic environment and was compared with the conventional stirring method. The effect of various operating parameters such as Ca(OH)2 slurry concentration, CO2 flow rate and Ca(OH)2 slurry flow rate on the particle size of CaCO3 was investigated. The calcium carbonate particles were characterized by Fourier transform infrared (FTIR), wide angle X-ray diffraction (WXRD) and particle size. The morphology was studied by using scanning electron microscopic (SEM) images. The particle size obtained in the presence of ultrasonic environment was found to be smaller as compared to conventional stirring method. The particle size is found to be reduced with an increase in the concentrations of Ca(OH)2 and increased with increasing CO2 flow rate for both the methods. The slurry flow rate had a major effect on the particle size and the particle size decreased with increased slurry flow rate. Only calcite phase of CaCO3 was predominantly present as confirmed by the characterization techniques for both the preparation methods. In most of the cases rhombohedral calcite particles were observed.
在超声环境下，于搅拌反应器中在室温下通过沉淀法连续生产碳酸钙（CaCO₃），并与传统搅拌法进行比较。研究了各种操作参数，如Ca(OH)₂浆料浓度、CO₂流速和Ca(OH)₂浆料流速对CaCO₃粒径的影响。通过傅里叶变换红外光谱（FTIR）、广角X射线衍射（WXRD）和粒径对碳酸钙颗粒进行了表征。利用扫描电子显微镜（SEM）图像研究了其形态。发现在超声环境下获得的粒径比传统搅拌法更小。两种方法中，粒径均随着Ca(OH)₂浓度的增加而减小，随着CO₂流速的增加而增大。浆料流速对粒径有主要影响，粒径随着浆料流速的增加而减小。通过两种制备方法的表征技术证实，仅方解石相的CaCO₃占主导地位。在大多数情况下，观察到菱形方解石颗粒。
