Potential Slow Release Fertilizers and Acid Soil Conditioners Obtained by One-Pot Mechanochemical Activation of Chrysotile:Cement Roofing Sheets with K2HPO4

• Autor(a) principal: Borges,Roger
• Data de Publicação: 2019
• Outros Autores: Wypych,Fernando
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Journal of the Brazilian Chemical Society (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532019000200326
• topic: chrysotile; cement roofing sheets; mechanochemical activation; slow release fertilizer

Chrysotile:cement roofing sheets were milled with and without K2HPO4. As indicated by X-ray diffraction (XRD), the samples crystallinities were reduced with the increasing milling time. The same tendency was observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), with disaggregation of the chrysotile fiber bundles and formation of non-fibrous micrometric agglomerate particles. After milling for 16 min, most of the phases present in the cement and chrysotile were transformed into amorphous materials, except quartz, in which the structure integrity was preserved, and calcium carbonate, where the particles were reduced to nanometric size. Both milled samples were submitted to release experiments in water, where the characteristics of a potential slow release fertilizer and acid soil conditioner were observed. The process is a viable alternative not only to eliminate the hazard of chrysotile fibers without the need to remove them from the cement matrix, but also as aggregation value to the milled almost amorphous mixture.