Enrichment of yellow passion fruit peel by the squeeze-flow technique using Lucina pectinata shell as a source of calcium carbonate

Abstract

The global discussion and adoption of practices related to sustainability, culminated in the reuse of residues from the agroindustry in accordance with the 3R's used in the country. According to current data from the IBGE, in 2020 Brazil produced 690 thousand tons of yellow passion fruit (M) - (Passiflora edullis f. flavicarpa), being the largest producer in the world. However, about 70% of this percentage is husk and seed, which if improperly discarded can cause impacts to the environment. The peel of this fruit is composed of cellulose, hemicellulose, lignin and pectin, which are connected through intermolecular calcium bridges, being able to establish interactions with species external to its structure, making it promising for reuse. In this sense, this study aimed to reuse the shells of Lambreta (L) - Lucina pectinata as a source of calcium carbonate, using it to enrich the yellow passion fruit peel using the squeeze-flow technique. The investigations were carried out from the variation of the proportionality between the two biomasses, generating new materials that were named ML11, ML12, ML13, LM12 and LM13. The effects of the mixture of biomasses were evidenced through the characterization techniques: FTIR, TG/DTG, DSC and SEM. The thermal degradation events of the samples were evaluated through the kinetic and thermodynamic parameters by the Kissinger method. The results obtained showed an increase in the thermal stability of the yellow passion fruit fiber constituents by enrichment with calcium carbonate from Lucina pectinata in samples ML11, ML12. It can be noted that the low activation energy in the LM12 and ML13 samples leads to a decrease in the thermal stability of these materials, indicating an ideal condition in the proportionality between the two biomasses involved, favoring the application of these materials in thermochemical processes. Through the observations carried out in the FTIR experiments, it was possible to observe the suppression of the band related to the -CO (1605 cm-1) stretching, indicating the efficiency of the squeeze-flow technique in the passion fruit structure, corroborating the micrographs obtained.