Synthesis of aluminum hydroxide nanoparticles from the residue of aluminum anodization for application in polymer materials as antiflame agents

The reuse and recycling of industrial waste for the production of new materials can be a viable alternative to contribute to environment preservation. An industrial process known to generate an important amount of waste is the anodization in the aluminum industry. As such, this study aimed to reuse residues from anodization processes in the synthesis and application of aluminum nanoparticles. The synthesis of the nanoparticles was carried out through precipitation in an aqueous medium. The efficacy of the process was determined by studying the effects of the temperature and the concentration of the two reagents employed: sodium hydroxide and hydrochloric acid. The experimental conditions were evaluated from a 23 experimental design. The synthesized materials were analyzed using XRF, XRD, FTIR, TEM and TGA. The results confirmed that nanoparticles were successfully obtained from the anodization residue. The nanoparticles synthesized were employed as flame-retardant additives in polymeric materials and their properties showed a good performance for industrial application. Moreover, by this synthesis it was possible to obtain aluminum hydroxide nanoparticles that after heat treatment was changed to aluminum oxide, being in both cases, materials which have a wide variety of applications.