Severity Factor as an Efficient Control Parameter to Predict Biomass Solubilization and Saccharification During Acidic Hydrolysis of Microalgal Biomass

A Correction to this article was published on 16 May 2020

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In this paper, the acidic pretreatment of microalgal biomass is investigated, and the solubilized biomass and hydrolyzed sugars were evaluated. The process is analyzed through the severity factor approach (acidic combined severity factor (ACSF)). A suitable kinetic model is developed and applied, and it is shown that the severity factor theory works. A discussion and comparison are presented with respect to the literature methods, which are mainly related to lignocellulosic biomass. In the case of microalgae, reaction orders for biomass and acid are shown to be the main parameters, and no other assumptions are needed. Two regions of the acidic treatment process have to be evaluated: low and high reactivity regions. Furthermore, a suitable experimental design is required in order to provide an appropriate reaction spectrum to obtain a good estimation of the kinetic parameters. A logarithmic severity factor range (ln ACSF) between 5 and 6 is able to solubilize around 80% of biomass and to hydrolyze more than 90% of sugars present in the biomass.

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  • 16 May 2020

    Reference: de Farias Silva, C.E., Bertucco, A. Severity Factor as an Efficient Control Parameter to Predict Biomass Solubilization and Saccharification During Acidic Hydrolysis of Microalgal Biomass. Bioenerg. Res. 11, 491���504 (2018).


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The authors would like to thank CNPq – Brazil (National Research Council of Brazil) - Process number 249182/2013-0, for the resources and fellowship. C.E.F. Silva designed and performed the experiments; summarized, analyzed, and discussed the results; wrote the article; and approved the final version. A. Bertucco analyzed the results, wrote the article, and approved the final version.


This study was funded by CNPq—Brazil (National Research Council of Brazil) Process number 249182/2013-0.

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Correspondence to Carlos Eduardo de Farias Silva.

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de Farias Silva, C.E., Bertucco, A. Severity Factor as an Efficient Control Parameter to Predict Biomass Solubilization and Saccharification During Acidic Hydrolysis of Microalgal Biomass. Bioenerg. Res. 11, 491–504 (2018).

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  • Phenomenological kinetics
  • Microalgae
  • Bioethanol
  • Acidic hydrolysis
  • Activation energy