Influence of Selected Saccharides on the Precipitation of Calcium-Vaterite Mixtures by the CO2 Bubbling Method

Abstract

Calcium carbonate is a compound existing in living organisms and produced for many biomedical applications. In this work, calcium carbonate was synthesized by a CO2 bubbling method using ammonia as a CO2 absorption promotor. Glucose, fructose, sucrose, and trehalose were added into the reaction mixture to modify characteristics of precipitated calcium carbonate particles. To determine the polymorphic form of produced calcium carbonate particles, Fourier transform infrared spectroscopy (FTIR-ATR) and X-ray diffraction (XRD) analysis were performed. Scanning electron microscopy (SEM) was used to estimate the size and shape of produced particles. Mixtures of vaterite and calcite were synthesized in all experiments. The percentage content of the vaterite in the samples depended on used additive. The highest concentration of vaterite (90%) was produced from a solution containing sucrose, while the lowest concentration (2%) was when fructose was added. Saccharides affected the rate of CO2 absorption, which resulted in a change in the precipitation rate and, therefore, the polymorphic composition of calcium carbonate obtained in the presence of saccharides was more varied.

Structure and phase analysis of calcium carbonate powder prepared by a simple solution method

“…The detailed quantitative results based on Rietveld refinement method analysis were then used for crystallite size calculation using the Scherer method [ 38 ]. Qualitative analysis of the synthesized CaCO 3 powder was carried out by comparing the vibration bending mode ratio between the vaterite phase in the 744 cm −1 area and calcite which was located at the wave number 711 cm −1 [ 39 ].

Figure 2 Space-filling representation of the crystal structure of trigonal calcite (a) and orthorhombic vaterite (b) in three dimensional lattice vectors; blue, brown and red sphere represent Ca atom, C atom, and O atom.

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“…The detailed quantitative results based on Rietveld refinement method analysis were then used for crystallite size calculation using the Scherer method [38]. Qualitative analysis of the synthesized CaCO 3 powder was carried out by comparing the vibration bending mode ratio between the vaterite phase in the 744 cm À1 area and calcite which was located at the wave number 711 cm À1 [39].…”

Synthesis Methods and Favorable Conditions for Spherical Vaterite Precipitation: A Review

“…Although amino acids did not promote the CO 2 absorption and the formation of high supersaturation, their stabilizing effect on the vaterite was prevalent. On the other hand, the addition of sucrose into the initial solution of calcium chloride and ammonia reduced the reaction time [85]. Sucrose facilitated the absorption of CO 2 and caused the high supersaturation in the system, which promoted the creation of vaterite.…”

Precipitation and Transformation of Vaterite Calcium Carbonate in the Presence of Some Organic Solvents

“…The results obtained in our experiments showed that the addition of an organic solvent to the reaction mixture reduced the proportion of vaterite in the freshly precipitated calcium carbonate particles, even when precipitation occurred faster, i.e., in the presence of isopropanol. Earlier studies on CaCO 3 precipitation by carbonation in the presence of ammonia indicated that acceleration of the CaCO 3 precipitation process promotes the formation of vaterite [15,49]. Moreover, vaterite stabilization is observed in systems containing carbamate ions, which can be formed in solutions containing ammonia or primary amines and bicarbonate ions [26,50].…”