Bioethanol preparation and separation from pineapple peel upon combining fermentation and pervaporation through biochar-containing PDMS membranes

Abstract

Ethanol is an alternative to replace the fossil fuels. Different sources have been studied to produce second generation ethanol, such as food waste. The goal in this work was the investigation of pineapple peel as sugar source for ethanol production by fermentation and its separation from the broth. Sugar from pineapple peel was extracted with water and the rich phase was pre-treated with filtration in cloth, and a conventional filter (14 µm). Then, the filtrate was fermented to ethanol using Saccharomyces cerevisiae. The fermentation broth was fed to a pervaporation system containing polydimethylsiloxane membranes, with 0 and 2 wt% biochar from pineapple waste, in order to purify bioethanol and remove it from the broth. The yield of bioethanol in fermentation broth was 88%, after 24 hours. Pervaporation tests revealed higher flux and selectivity for non-containing biochar membranes, showing values of 120 g/m²h and 1.0 v/v% of ethanol in permeate. The results showed the potential of the use of pineapple waste as the sugar source for biofuels such as bioethanol.