Currently, studies with bioceramics are gaining prominence and being much explored, especially hydroxyapatite (Hap), due to it structural versatility, presenting it self as one of the main calcium phosphates in nature, more stable and more insoluble in ambient conditions, having 30% to 70% of the mass of bones and teeth, making it interesting to use as a biomaterial – as they are highly biocompatible and osteointegrators -, bioestimulators, acting in the process of generating fuels, among others.

Calcium oxide for the production of hydroxyapatite was obtained, in this work, using chicken eggshell, and to improve the porosity, which is the focus of the present study, starch was added.

Porosity is an interesting factor both in the production of biomaterials and catalysts because they confer unique properties to the material when compared to a non-porous material. The distribution, size and geometry of pores also change the properties of ceramics. Both for biomaterials and for catalysts, the greater the amount of pores, the greater the area of the solid, and both in adhesion to bone and in its catalytic reaction, it takes place on the surface of the solid, so the greater the surface, the more reactions will occur and the more effective will be the solid. These properties lead to important applications such as selective separation of molecules, selective catalysis to products, reagents or intermediates, selective adsorption, etc.

In this context, the present work aims to compare the distribution of pores, as well as their size and geometry, between the hydroxyapatite produced by adding starch as a porogenic agent and the “ambient” hydroxyapatite (without the use of porogenic agents). The samples were submitted to Scanning Electron Microscopy (SEM), Thermogravimetric Analysis (TGA) and Fourier Transform Infrared Spectroscopy (FTIR) analyses, verifying an increase in porosity in the sample with starch which, as seen, is important for its role as a catalyst.