No abstract

No abstract

This paper analyses the growth of the adsorbed layer during the course of N 2 adsorption verified in two types of elliptical pores, oblates and prolates, by means of the Broekhoff de Boer theory. The information provided by the value of the thickness of the adsorbed layer permits to characterize the geometrical features of the liquid-vapour interface at every stage of the isotherm, prior and at the onset of capillary condensation. The features of the liquid-vapour interface that are characteristic of the instability at the onset of capillary condensation were identified. Additionally, the critical ellipsoidal pore sizes were calculated, thus identifying the limit of stability for the formation of the liquid-vapour interface during N 2 adsorption.

Objective: To quantify the production of total and reducing sugars, as well as bioethanol from sugarcane bagasse (Saccharum spp.) pretreated with Trametes versicolor and 20 % (P/V) NaOH solution. Design/methodology/approach: An experimental 2K design was used to determine the effect of the volume of inoculant added to wild sugarcane bagasse samples (Factor A; 8 and 10 mL), its incubation period (Factor B; 18 and 24 d), and the bagasse weight/ volume of 20% (P/V) NaOH solution (Factor C; 5 and 20%(P/V), on the production of total and reducing sugars during simple saccharification. ANOVA analysis was used to evaluate the significance of these factors. The production of bioethanol was achieved via simple fermentation using a commercial strain of Saccharomyces cerevisiae. Results: It was found that the highest yields of reducing and total sugars were obtained with the use of 10 mL of inoculant solution and with an 18 d incubation period during biological pretreatments. The ANOVA analysis suggests that Factors A and B influence the release of sugars, while Factor C was irrelevant. The bioethanol production registered concentrations of up to 7.3 mg mL-1 for every 5 g of sugarcane bagasse. Limitations/implications: This study focused on how treatments using T. versicolor and NaOH affected the release of sugars. Optimization of bioethanol production needs to be considered subsequently in another study. Findings/conclusions: The results have implications for the use of pretreatments for the production of bioethanol from agro-industrial residues.