Produção de bioetanol a partir da amêndoa da semente da manga (Mangifera indica L.).

Abstract

It is a growing need to develop technologies aimed at producing clean energy such as biofuels (ethanol) from starchy materials, which are rich in fermentable sugars. In recent years it comes to observing the world a great interest in the use of agro-industrial waste in getting renewable fuels, such as bioethanol. Thus, this work was developed with the aim of studying and determine optimized conditions for the production of bioethanol using the process of acid hydrolysis of starch extracted from seed kernels removed from the sleeve (Mangifera indica L.) followed by fermentation submerged by Saccharomyces cerevisiae. The starch extracted from seed of the sleeve was removed by decantation, at temperatures below 10 ºC for 72 h, dried at 50 °C, sieved (65mesh) and only then was characterized. The practical performance presented extraction processes, was 14.86% and the yield of dry matter was 3.25%, with high purity. The observation scanning electron microscopy showed starch granules natural mango with ellipsoid and oval shape, with dimensions of 19.6 mm in length and 10.9 mm in width. The pattern shown crystallinity by X ray diffractometry, was from the type A typical grains and a degree of crystallinity of 19.4%; Then, the starch was subjected to acid hydrolysis using, as a catalyst, sulfuric acid (H2SO4), and phosphoric acid (H3PO4) at different acid concentrations (1, 3 and 5), ratio 1: 8, different temperatures (80, 100, 120 °C) for 30, 60 and 90 minutes of reaction. The starch based on its chemical and physical-chemical with the value of 60.72% characterization has promising source of glucose to acid hydrolysis aimed at obtaining bioethanol. In the process of acid hydrolysis for both types catalysts the best results are obtained glucose concentrations at 120 ° C, acid concentration of 5% and the starch weight ratio of 1:8, with the yield for the hydrolysis H2SO4 (89.4%) and the (H3PO4) of (75.5%) process mainly this effective in removing inhibitors; longer fermentation these hydrolysates was also satisfactory for both conditions evaluated, with factor conversion of glucose to ethanol from 51% to 47% H2SO4 and H3PO4 for. The fermentation tests of the hydrolysates using industrial Saccharomyces cerevisiae Y-904 strain in beaker with 500 mL of medium, shaken at 170 rpm, 32 °C 0 followed by 12h of fermentation. The productivity and efficiency of the process of obtaining ethanol from starch extracted from seed kernel of the sleeve, the value of 0.042 g / Lh of ethanol and 100% for the hydrolyzate liquor with sulfuric acid. Thus, it was demonstrated excellent potential of the ethanol production process from starch extracted from the seed kernel of mango using H2SO4 catalyst.