Dynamic Modeling Application To Evaluate the Performance of Spathaspora passalidarum in Second-Generation Ethanol Production: Parametric Dynamics and the Likelihood Confidence Region

Abstract

Lignocellulosic materials and agro-industrial residues are essential in a sustainable biorefinery. The effective fermentation of renewable sugars is still an important challenge for an economically viable production of biofuels and biochemicals. This challenge involves biological aspects, such as choosing the microbial platform, and industrial aspects. These aspects can be assessed employing mathematical models to understand the complex synergies between the microorganism and processes. In this work, the performance of the yeast Spathaspora passalidarum was evaluated for the fermentation of xylose and glucose at different proportions, initial concentrations, and initial cell densities using an unstructured−unsegregated kinetic model. The likelihood confidence region, correlations between the parameters, and the convergence of the parameters through the optimization process were identified. It was also possible to identify that π Xyl, max , μ Glu, max , K ' S, Xyl , Y ' PEth/SGlu , Y ' PEth/SXyl , and Y ' X/SGlu were the most representative parameters, due to the high correlation (positive and negative) they have with the other model parameters. It was also possible to identify how initial substrate concentrations affected the specific uptake substrate and ethanol production rates; in this sense, the increase in the glucose concentration causes a decrease in the specific ethanol formation rate at a high concentration of xylose for S. passalidarum cultivated in the conditions proposed by this study.

Sorption behavior and mechanisms of thallium to microplastics

“…The fitting results of the adsorption kinetics of the PS group showed that the PSO model fitted better at low initial Tl(I) concentration, and the distance to the data points was closer than that of the PFO model, which indicated that chemical adsorption might be the main mechanism for adsorption between PS and Tl(I) (Ho and McKay, 2000;Santos et al, 2021). The chemical mechanism may involve electron sharing and exchanging, complexation, coordination and/or chelation between Tl(I) and MPs (Martinez-Jimenez et al, 2021). Based on the theory proposed by Weber and Morris (Weber and Boell, 1962), the Weber and Morris Model was used to identify the intra-particle diffusion mechanism (Figure S1).…”

Statistical Analyses of a Population Balance Model of a Batch Crystallization Process

“…Simplifying assumptions, including disregarding variable correlations and assuming a Gaussian distribution of parametric errors, are applied without fully considering the possible implications, raising doubts about the significance of the estimated parameters and the validity of interpretations regarding the observed kinetic phenomena . On the other hand, other fields of chemical processes, such as biotechnology − and catalysis, − have recognized the importance of analyzing experimental data for the development of appropriate models.…”