Influence of freezing in the obtainment of adsorbent carbon precursor blocks made with bananas

Abstract

The use of residues from banana cultivation in the elaboration of adsorbent materials has presented itself favorable due to the decrease of production costs, and also because it provides value to the raw material, and helps to achieve good results, which have been registered by several case studies. The aim of this work was tocharacterize adsorbents carbons elaborated from green and ripe bananas, employing peels, pulp, and whole-grain fruits. For that, it was considered two methodologies that involved or not the freezing as one of the stages in the obtaining of precursor blocks of adsorbent carbons. The physicochemical properties of carbons were evaluated, showing that there were no significant differences in the variables moisture and mass yield, with regard to the use of freezing as one of the stages of blocks confection. Carbons made from green and ripe bananas peels presented lower ash content when it was not employed the freezing. The blocks made with green bananapeels and ripe banana pulp presented more relative density when it was used the freezing. Only the relative density of the blocks made with ripe bananaspulp has presented differences, in which the freezing influenced in the decrease of value of this parameter. Theadsorbents total porosity was larger when it was not used the freezing in the elaboration of the majority of blocks types. Therefore, the use of the freezing proved to be important to promote the agglutination of the mass made with bananas, thus, giving the format and the compaction of the blocks until the end of processing. However, this stage was not relevant, in view of the evaluated physicochemical characteristics.