Turbo-Mixing Reactive Precipitation Lab Analysis
Abstract. An innovative and novel technology method of processing called Turbo-Mixing Reactive Precipitation (TMRP) design proposed as an alternative to this current processing or conventional productions of finer precipitation calcium carbonate (nano-PCC) in turbo-mixing conditions. In this paper, the effect of the stirring rate onto morphology, particle sizes and reaction time of the precipitated CaCO3 particles was discussed. CaCO3 nano particles with an average particle size of approximately 15.75 nm were successfully obtained by stirring rotation speed at 900 rpm. The structural analysis was conducted using a Scanning Electron Microscope (SEM) and a Field Emission Scanning Electron Microscope (FESEM) and results showed that the increasing
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The crystallinity, morphology, structure, shape and molecule size of precipitated calcium carbonate were directly influenced by the stirring action during the carbonation process. As depicted in the Fig. 1, SEM images of nano CaCO3 precipitated at different stirring rate varied from 700, 800, 900, 1000, 1100 and 1200 rpm had shown significant differences in morphology structure influenced by agitation rate, respectively. Results revealed that in Fig. 1 (a) and (b) the particle morphology was tended to rhombic-calcite. Meanwhile, Fig. 1 (c) and (d) showed structured more likely to needlelike-aragonite and Fig. 1 (e) and (f) were indicating to spherical-vaterite. This can be explicated from the perspective of the co-effects of micro-macro mixing and mass transfer theory. At low multiple impeller stirring rotation speed, the level of supersaturation had a wide variety of different local areas in the interface region between particle and agitation medium. Meanwhile, when the multiple impeller stirring rotation speed was excessively high, the micro-macro mixing was significantly increased, and the CO2 transfer coefficient was additionally intensified into the system. Higher multiple impeller stirring rotation speed also will provide a better homogeneity and heterogeneity of nucleation of nano-precipitated CaCO3. This finding was supported by previous researchers' work such as M. Wang et. al., Laifeng et. al. and Martin Back et. al. which described and discussed deeply about the transformation of CaCO3 morphology, influenced by numerous parameters
The crystallinity, morphology, structure, shape and molecule size of precipitated calcium carbonate were directly influenced by the stirring action during the carbonation process. As depicted in the Fig. 1, SEM images of nano CaCO3 precipitated at different stirring rate varied from 700, 800, 900, 1000, 1100 and 1200 rpm had shown significant differences in morphology structure influenced by agitation rate, respectively. Results revealed that in Fig. 1 (a) and (b) the particle morphology was tended to rhombic-calcite. Meanwhile, Fig. 1 (c) and (d) showed structured more likely to needlelike-aragonite and Fig. 1 (e) and (f) were indicating to spherical-vaterite. This can be explicated from the perspective of the co-effects of micro-macro mixing and mass transfer theory. At low multiple impeller stirring rotation speed, the level of supersaturation had a wide variety of different local areas in the interface region between particle and agitation medium. Meanwhile, when the multiple impeller stirring rotation speed was excessively high, the micro-macro mixing was significantly increased, and the CO2 transfer coefficient was additionally intensified into the system. Higher multiple impeller stirring rotation speed also will provide a better homogeneity and heterogeneity of nucleation of nano-precipitated CaCO3. This finding was supported by previous researchers' work such as M. Wang et. al., Laifeng et. al. and Martin Back et. al. which described and discussed deeply about the transformation of CaCO3 morphology, influenced by numerous parameters