| Calcium carbonate is an important functional filler and widely used in paper, paint and reconstituted tobacco industries, etc. As a filler used in reconstituted tobacco, not only could improve the physicochemical properties of reconstituted tobacco, but also could improve smoking quality and reduce production cost with appropriate amount. In the production process, actually, this filler retention rate is not high, which lead to serious loss of calcium carbonate and pulp whitewater pollution, limiting the calcium carbonate filler’s function. Therefore, the modified preparation for calcium carbonate will be a feasible way to solve this problem.Modified calcium carbonate were synthesized by gas-liquid carbonization method, (NaPO3)6and C6H807as the modifier, C4H5KO5 and K3C6H5O7-H2O as additive (ratio of 1:1, in an amount of 2%). The (NaPO3)6 and C6H8O7 on the impact modification effect and the mechanism of CaC03 were studied. Further the two complex were discussed and the complex optimum proportion were got. The effects of initial carbonation temperature, the amount of additives, the concentration of Ca(OH)2 and CO2 were studied, too. We determined the optimum parameters that could synthetic excellent performance modified CaCO3 through the orthogonal experiment. Last, the modified CaCO3 were used in the reconstituted tobacco production. At the same time, the different proportions of CaCO3 filler and different types of diatomaceous earth to the effects of reconstituted tobacco ash and the mainstream smoke were researched.When (NaPO3)6 is added into Ca(OH)2 slurry, hydroxyapatite structure was formed on the CaCO3 surface and increasing the steric hindrance of CaCO3 growth process, results in preferred orientation growth for the spindle. Citric acid and Ca2+ formed the chelate calcium citrate by coordination bonds in the slurry, it adsorbed on the surface of the CaCO3 grains and reduced the surface energy of the crystallite. That could keep the CaCO3 crystal nucleus stable in the system. When increasing the amount of C6H8O7, calcium carbonate particle size decreases. The results show that when (NaPO3)6 and C6H8O7 complex ratio of 1:1, the average particle size of calcium carbonate prepared as 4.82 μm, specific surface area of 11.573 m2/g, the morphology is spindle-shaped.The technological parameters were optimized by the orthogonal experiment. The results show that the modified calcite CaCO3 with average particle size of 4.91 μm, the specific surface area of 16.431 m2/g and the ash content of 19.25% can be prepared at the carbonization temperature of 40℃, the compound modifier amount of 1%, the CO2 concentration of 100% and with the Ca(OH)2 concentration of 9%.Both the research and the applications have shown that the ash content 8.25% higher than the commercial CaCO3 when the modified CaCO3 was added to the reconstituted tobacco, the main stream smoke and smoking quality results are better than the commercial CaCO3. Moreover, with the increase of adding amount of modified CaCO3 gradually, the ash content also gradually rise. In addition, the ash content of 17.16% diatomite higher than the commercial CaCO3 and the release amount of the carbon monoxide, nicotine, tar volume can be reduced.
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