Ostrich Eggshell as an Alternative Source of Calcium Ions for Biomaterials Synthesis

Obtaining hydroxyapatite with different precursors for application as a biomaterial

“…Manhães et al [55] synthesized calcium phosphates by wet neutralization reaction, from the precursor calcium chloride (CaC l2 .2H 2 O) with atomic ratio Ca/P of 1.67, and calcination at 800 °C, and observed by granulometric analysis a wide distribution of agglomerate sizes, with values of mean diameter of 12 μm; in the samples obtained in this work, the mean diameter of the agglomerates was 0.9 μm, which consequently had enhanced surface area that favors absorption by the organism. The tendency of particle agglomeration was higher for the smaller particles, which agreed with the literature [3,49,56].…”

“…In the samples obtained by the two routes the characteristic peaks of HAp were present. An observed difference between the HAp obtained was related to the presence of a peak in the region of 1600 and 3400 cm -1 , relative to the OH group of the lower intensity hydroxyl in sample 2, possibly from the presence of structural H 2 O; bands at 1470 and 1420 cm -1 of symmetrical stretching of the C-O group were also identified [56,60,61]. According to the result of the FTIR it was observed that the hydroxyapatite obtained by the biological precursor had less amount of hydroxyl group (OH) in the structure, which may be associated with increased crystallinity of the same, corroborating with the XRD results and confirming the greater stability of the microstructure when compared to the mineral precursor.…”

Nanostructured Hydroxyapatite from Hen´s Eggshells Using Sucrose as a Template

“…Figure 1 shows the XRD diffractogram and the XRF results of the CaO obtained from hen´s eggshells calcined. The diffractogram shows the peaks exclusively for CaO, indexed according to ICSD 52783, indicating that the temperature and time used were sufficient for the complete transformation of CaCO 3 into CaO, as also reported by Caliman et al 32 for ostrich eggshells.…”

The circular economy of agro and post‐consumer residues as raw materials for sustainable ceramics

“…4 In particular, regarding ceramic materials, several scientific works propose agro-industrial residues in tiles, bricks, cements, foam glasses, bioceramics, geopolymers, etc. [5][6][7][8][9][10][11][12][13][14][15][16][17] Looking at chemical composition and calorific power of agro residues, exists the real possibility of exploiting both the organic component to create lightening and to low the firing temperature, and the inorganic ones, represented for example by the presence of specific elements useful for a functionalization (eg, presence of phosphorus into cattle bone flour ash available for a fertilizer effect). In this specific area that the research of the authors, aimed at making ceramic products, has been developed in the past and present years.…”