Dynamic Analysis of Bioethanol Production from Corn Stover and Immobilized Yeast

Abstract

The use of low cost and abundant corn stover in yeast fermentation can reduce product costs. In this study, bioethanol was produced from a hydrolysate of corn stover using immobilized yeast. A kinetic model was established for the total reducing sugar consumption and the production of bioethanol. The parameter estimation for kinetic modeling considered the main process variables during bioethanol production from corn stover. Total reducing sugar concentrations decreased exponentially in the bioethanol fermentation for 6 h; consumption was more than 90%. To use kinetic modelling of yeast growth for bioethanol fermentation, the value of μmax reached 0.2891 h -1 , and the matrix inhibition constant (KIS) and production inhibition constant (KIP) were 8.9154 g/dm 3 and 0.00676 g/dm 3 , respectively. To use kinetic modelling of fermentation time on bioethanol, the maximum ratio of bioethanol production rate (qmax) reached 1.427 g/g•L. However, KIS was 2.813 g/dm 3 , and KIP was 0.0149 g/dm 3 .

Bioconversion of pomegranate residues into biofuels and bioactive lipids

“…These discrepancies may be due to the presence of growth inhibitors on PR extract that are not included in the Hinshelwood model. The estimated values of K pp , K px , K sx and K sp are in the range of values reported in the literature (Birol et al, 1998; Jin et al, 2012; Kostov et al, 2012; Tian and Chen, 2016).…”

“…The μ max values ranged between 0.0038 and 0.0079 1/h, except for the value obtained from the yeast S. coipomoensis in anaerobic conditions, which was 0.00024 1/h. The corresponding values in the literature using the Hinshelwood model range from 0.231 to 0.289 1/h by using free or immobilized cells of yeast S. cerevisiae growing on glucose (Kostov et al, 2012), sweet sorghum stalk juice (Jin et al, 2012) and corn stover (Tian and Chen, 2016). The low μ max values in the present study may be due to the cell growth inhibition by ethanol and/or inhibitory compounds generated during PRs pretreatment.…”

Bioconversion of pomegranate residues into biofuels and bioactive lipids

“…The ߤ ௫ values ranged between 0.0038 and 0.0079 1/h, except for the value obtained from the yeast S. coipomoensis in anaerobic conditions, which was 0.00024 1/h. The corresponding values in the literature using the Hinshelwood model range from 0.231 to 0.289 1/h by using free or immobilized cells of yeast S. cerevisiae growing on glucose (Kostov et al, 2012), sweet sorghum stalk juice (Jin et al, 2012) and corn stover (Tian and Chen, 2016). The low ߤ ௫ values in the present study may be due to the cell growth inhibition by ethanol and/or inhibitory compounds generated during PRs pretreatment.…”

“…Specifically, bioethanol apart from its variety of commercial applications in cosmetology and in food and pharmaceutical industry, is also widely used as an engine fuel, on its own, or blended with gasoline. However, the utilization of the so-called "1 st generation" bioethanol, deriving from the fermentation of hydrolyzed corn starch or sucrose juice, runs into the "food vs fuel" dilemma (Gray et al, 2006), therefore the production of the so-called "2 nd generation" bioethanol (deriving through the valorization of waste streams) is considered as a very important scientific priority worldwide (Rastogi and Shrivastava, 2017;Sarkar et al, 2012;Tian and Chen, 2016). On the other hand, biodiesel produced by a variety of renewable resources (i.e.…”

Waste Cassava Tuber Fibers as an Immobilization Carrier of Saccharomyces cerevisiae for Ethanol Production

“…Popular methods of immobilizing cells for ethanol fermentation include calcium alginate entrapment and natural adsorption because the techniques are simple and conduct under mild condition (Razmovoski and Vučurović 2011;Zheng et al 2012;Tian and Chen 2016). When using entrapment, yeast cells inoculated are trapped within a gel matrix and they are maintained throughout fermentation; conversely, the cells trapped inside the calcium alginate beads may suffer from a mass transfer limitation of nutrients and O2, as well as the removal of the CO2 and ethanol produced (Phisalaphong et al 2007;Yu et al 2007;Zhu 2007).…”