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Biochars (BCs) are very versatile adsorbents, mainly, in the effectiveness of adsorption of organic and inorganic compounds in aqueous solutions. Here, the sugarcane biomass (SCB) was used to produce biochar at different carbonization times: 1, 2, 3, 4, and 5 h, denominated as BC1, BC2, BC3, BC4, and BC5, respectively. The superficial reactivity was studied with adsorption equilibrium experiments and kinetics models; Methylene Blue (MB) was used as adsorbate at different pH values, concentrations, and temperatures. In summary, the carbonization time provides the increase of superficial area, with exception of BC4, which decreased. Equilibrium studies showed inflection points and fluctuations with different initial dye concentration and temperature; SCB showed the best adsorption capacity compared to the BCs at the three temperatures tested, varying with the increase of MB concentration, suggesting the dependence of these two main factors on the adsorption process. The proposed adsorption mechanism suggests the major influence of Coulomb interactions, H-bonding, and π-interactions on the adsorption of MB onto adsorbents, evidencing that the adsorption is led by physical adsorption. Therefore, the results led to the use of the SCB without carbonization at 200 °C, saving energy and more adsorbent mass, considering that the carbonization influences weight loss. This study has provided insights of the use of SCB in MB dye adsorption as a low-cost and eco-friendly adsorbent.

-An autonomous sugarcane bioethanol plant was simulated in EMSO software, an equation oriented process simulator. Three types of fermentation units were simulated: a six parallel fed-batch reactor system, a set of four CSTR in steady state and one consisting of a single stoichiometric reactor. Stoichiometric models are less accurate than kinetic-based fermentation models used for fed-batch and continuous fermenter simulations, since they do not account for inhibition effects and depend on a known conversion rate of reactant to be specified instead. On the other hand, stoichiometric models are faster and simpler to converge. In this study it was found that the conversion rates of sugar for the fermentation systems analyzed were predictable from information on the composition of the juice stream.Those rates were used in the stoichiometric model, which accurately reproduced the results from both the fed-batch and the continuous fermenter system.

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A pandemia do novo Coronavírus (COVID-19) provocou uma série de mudanças em todo o mundo. A educação teve que se readequar para atender todos os alunos de todos os níveis de ensino. No entanto, problemas foram evidenciados sobre diversos aspectos, principalmente pela baixa acessibilidade dos estudantes. Assim, compreender a visão dos alunos em relação ao Ensino Remoto Emergencial (ERE) é de suma importância para a melhor readequação das aulas, considerando que milhões de alunos no Brasil não possuem infraestrutura básica como computador e internet, para continuarem as aulas pelo ERE. Nesse sentido, esta pesquisa teve como objetivo identificar as possibilidades e desafios na aprendizagem de estudantes do ensino médio no ERE. No processo metodológico desta investigação de abordagem qualitativa, utilizou-se um questionário aplicado via Google Forms, com os discentes de um colégio estadual. Os resultados sinalizam como possibilidades, a continuidade dos estudos, poder estudar em casa e flexibilização de horário; a ausência de contato físico e diálogo com os professores, provocaram dificuldades de aprendizagem como consequência.