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The steam explosion was carried out in the absence (autohydrolysis) and presence of phosphoric acid to evaluate the effects of temperature (180 and 210 °C), acid concentration (0 and 19 mg g -1 , dry basis) and pretreatment time (5 and 10 min) on the structure and reactivity of sugarcane bagasse. Glucan recovery was used as the main response factor for pretreatment optimization through a central composite design. Autohydrolysis at 210 °C for 10 min had a good pretreatment performance but phosphoric acid catalysis (19 mg g -1 ) resulted in better yields under considerably milder conditions (180 °C, 5 min). Hydrolysis of both substrates for 96 h using 8 wt.% total solids and 30 mg g -1 Cellic ® CTec2 (Novozymes) provided total glucose yields of 75% in average. The production of cellulosic ethanol was assessed by both separate and simultaneous hydrolysis and fermentation using Saccharomyces cerevisiae. Freeze-drying of pretreatment water solubles reduced the concentration of furfural, hydroxymethylfurfural and acetic acid by more than 80% and this eliminated their inhibitory effect on yeast fermentation.

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The use of biofuels is increasingly important in order to mitigate the consumption of petroleum and increase the energy use of renewable sources. The estimative is that in 2040 the demand for oil will intensificate by 26% and part of it will have to be supplied by renewable energy. Biofuels offer a reliable alternative and among the process associated to biofuels production, thermal cracking results on a liquid product (bio-oil) with similar characteristics to the fossil fuels, particularly when performed with triglyceride sources (TG). In this sense, the main goal of this work is to propose an alternative sequence of chemical processes aiming to boost an oil refinery chain into a green refinery by producing, co-processing and improving bio-oil characteristics obtained from triglyceride source. Some bio-oil characteristics like density, acidity (AI), iodine index (II), oxygen content (OC), carbon number distribution and chemical compositions are presented. The properties of bio-oil obtained from the thermal cracking of triglycerides might be compared to petroleum and its derivate. Although the characteristics are similar between them, the bio-oil requires upgrading to reduce its high acid index, until achieve levels acceptable for its processing at a refinery. The content of olefins and oxygen might be reduced through hydrotreatment process. The hydrotreatment can promote the saturation of the double bonds and remove the oxygen atoms. The hydrotreatment unit is present in most of the refineries and further investigations are required to evaluate the hydrogen consumption. The proposal of this work is divided in four steps: the first is to produce bio-oil through triglyceride’s thermal cracking in a continuous and steady state regime; the second process is to promote the esterification of bio-oil to reduce its acid index; the third stage is co-processing bio-oil in a distillation unit being fractionated into desired fractions; the fourth step involves hydrotreatment to reduce both iodine index and oxygen content. Thus, the co-processing of bio-oil appears to be a promising approach to increasing the biofuels content in an oil refinery, to reduce sulfur and to maintain the quality parameters of commercial fuels.

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This article presents the experimental data on distillation of bio-oil obtained from thermal cracking of a mixture of castor oil and its methyl esters. The interpretation of the data can be found in Menshhein et al. (2019) available on https://doi.org/10.1016/j.renene.2019.04.136. Experiments were carried out using a simple distillation apparatus and the products were quantified and qualified from Gas Chromatography – Flame Ionization Detector (GC-FID) with standards compounds. Data were presented in terms of distillation equipment and distillation curve values of volume and temperature of the crude bio-oil sample. Information about GC-FID methods and chromatograms of from standard heptaldehyde and methyl undecenoate and their analytical curve. Carbon number data of crude bio-oil sample was also showed.