SABINE NEUSATZ GUILHEN

SABINE NEUSATZ GUILHEN

(Fonte: Lattes)

Resumo

Possui graduação em Química com atribuições Tecnológicas e Biotecnológicas pelo Instituto de Química da Universidade de São Paulo (2005), mestrado (2009) e doutorado (2018) em Tecnologia Nuclear (Materiais) pelo Instituto de Pesquisas Energéticas e Nucleares (IPEN), Universidade de São Paulo. Tem experiência em Química Analítica com ênfase em Análise de Traços, atuando principalmente no desenvolvimento de métodos analíticos empregando técnicas espectrofotométricas (AAS, ICP OES e ICP-MS) para caracterização de amostras ambientais, arqueológicas, biológicas, forenses e nucleares. Atualmente, ocupa o cargo de Tecnologista em "Caracterização Química" no Centro de Química e Meio Ambiente (CQMA) do IPEN (CNEN/SP), onde desempenha atividades de pesquisa e desenvolvimento tecnológico em atendimento às demandas institucionais ligadas ao Ciclo do Combustível Nuclear e aos Programas de Pesquisa de caráter multidisciplinar, em apoio a projetos de Inovação Tecnológica e ao Programa de Pós-Graduação do IPEN/USP. Além disso, atua na geração de produtos tecnológicos e no desenvolvimento de materiais adsorventes de baixo custo e alto valor agregado visando o aproveitamento de materiais e resíduos naturais e/ou renováveis no tratamento de efluentes e rejeitos. (Texto extraído do Currículo Lattes em 4 maio 2023)

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Biosorption of methylene blue by bone meal
2024 - ARAUJO, LEANDRO G. de; MARTINS, GABRIEL F.; CAMPERA, ALEXSSANDRA A.A.; MARUMO, JULIO T.; GUILHEN, SABINE N.
Sorption technologies have been proposed for the treatment of water containing methylene blue (MB), a toxic and persistent pollutant. Despite its environmental risks, the role of process variables in MB removal has not been fully explored through experimental design. The objective of this study is to assess the potential of bone meal powder (BMP), an underexplored agricultural byproduct, as an affordable adsorbent for the removal of MB from water. BMP was subjected to a series of analytical characterization techniques, and its adsorption capacity was evaluated through a comprehensive factorial design, which investigated the effects of biosorbent dosage, solution pH, and initial MB concentration. The study revealed that the highest adsorption level was 14.49 mg g−1, attained under the following conditions: 1 g L−1 BMP, pH 11, and 100 mg L−1 MB. The adsorption equilibrium was reached within 60 min, with a measured capacity (qexp) of 18 mg g−1. Theoretical adsorption isotherms indicated a capacity of 63 mg g−1, which aligned well with the Langmuir model. To predict adsorption outcomes, machine learning models were applied, with multiple linear regression performing best. Optimization of decision trees and neural networks improved accuracy but risked overfitting. FT-IR, XRD, and ICP analyses indicated ion exchange as a significant mechanism of adsorption. In desorption studies, H2SO4 was the most effective agent, achieving 68.72% desorption efficiency. BMP exhibited optimal recyclability for up to four cycles before efficiency declined.
Uranium biosorption by hydroxyapatite and bone meal
2022 - WATANABE, TAMIRES; GUILHEN, SABINE N.; MARUMO, JULIO T.; SOUZA, RODRIGO P. de; ARAUJO, LEANDRO G. de
Biosorption has been examined for the treatment of aqueous solutions containing uranium, a radiotoxic pollutant. Nevertheless, the evaluation of the role of process variables by experimental design on the use of hydroxyapatite and bone meal as biosorbents for uranium has not yet been previously addressed. In this study, the effects of adsorbent dosage (M), initial uranium concentrations ([U]0), and solution pH were investigated, using a two-level factorial design and response surface analysis. The experiments were performed in batch, with [U]0 of 100 and 500 mg L−1, pH 3 and 5, and adsorbent/uranium solution ratios of 5 and 15 g L−1. Contact time was fixed at 24 h. Removal rates were higher than 88%, with a maximum of 99% in optimized conditions. [U]0 and M were found to be the most influential variables in U removal in terms of adsorption capacity (q). The experiments revealed that bone meal holds higher adsorption capacity (49.87 mg g−1) and achieved the highest uranium removal (~ 100%) when compared to hydroxyapatite (q = 49.20 mg g−1, removal = 98.5%). The highest value of q for both biomaterials was obtained for [U]0 = 500 mg L−1, pH 3, and M = 5 g L−1. Concerning the removal percentage, bone meal achieved the best performance for [U]0 = 500 mg L−1, pH 3, and M = 15 g L−1. Further experiments were made with real radioactive waste, resulting in a high uranium adsorption capacity for both materials, with 22.11 mg g−1 for hydroxyapatite and 22.08 mg g−1 for bone meal, achieving uranium removal efficiencies higher than 99%.
Role of point of zero charge in the adsorption of cationic textile dye on standard biochars from aqueous solutions
2022 - GUILHEN, SABINE N.; WATANABE, TAMIRES; SILVA, THALITA T.; ROVANI, SUZIMARA; MARUMO, JULIO T.; TENORIO, JORGE A.S.; MASEK, ONDREJ; ARAUJO, LEANDRO G. de
The point of zero charge (PZC) is an inherent electrokinetic property of biochars (BC). It influences the adsorption process under certain pH conditions. Herein, we report the method of determination of the PZC values of ten standard BCs. We used the salt addition method to select the BCs with suitable properties for methylene blue (MB) removal from aqueous solutions. The standard BCs were obtained by pyrolyzing five different biomasses at two distinct temperatures (550°C and 700°C). The BCs derived from rice husk (pHPZC at 7.22 and 7.64 for RH550 and RH700, respectively) and softwood pellets (pHPZC at 6.57 and 6.78 for SWP500 and SWP700, respectively) were selected for their compatibility with cationic dyes such as MB. Results from adsorption experiments indicated the potential use of the RH biochar as an adsorbent for the removal of MB from aqueous solutions. The removal efficiencies were 68.83% and 71.97% for RH550 and RH700, respectively. Considerably low values were obtained for SWP550 and SWP700 (21.61% and 22.84%, respectively). Equilibrium was achieved at 2 h for RH550 and 1 h for RH700, and the adsorption kinetics for the RH BCs could be described by a pseudo-second order equation. The results revealed that even when produced under comparable conditions, BCs obtained from different feedstocks exhibited different cationic dye removing abilities. BCs optimized for the removal of cationic or anionic dyes can be easily engineered by appropriately matching the feedstock with the processing conditions.
Uranium removal from aqueous solution using macauba endocarp-derived biochar
2021 - GUILHEN, SABINE N.; ROVANI, SUZIMARA; ARAUJO, LEANDRO G. de; TENORIO, JORGE A.S.; MASEK, ONDREJ
The main aim of this study was to evaluate options for addressing two pressing challenges related to environmental quality and circular economy stemming from wastage or underutilization of abundant biomass residue resources and contamination of water by industrial effluents. In this study we focused on residues (endocarp) from Macaúba palm (Acrocomia aculeata) used for oil production, its conversion to activated biochar, and its potential use in uranium (U) removal from aqueous solutions. Batch adsorption experiments showed a much higher uranyl ions (U(VI)) removal efficiency of activated biochar compared to untreated biochar. As a result of activation, an increase in removal efficiency from 80.5% (untreated biochar) to 99.2% (after activation) was observed for a 5 mg L 1 initial U(VI) concentration solution adjusted to pH 3 using a 10 g L 1 adsorbent dosage. The BET surface area increased from 0.83 to 643 m2 g 1 with activation. Surface topography of the activated biochar showed a very characteristic morphology with high porosity. Activation significantly affected chemical surface of the biochar. FTIR analysis indicated that U(VI) was removed by physisorption from the aqueous solution. The adsorbed U(VI) was detected by micro X-ray fluorescence technique. Adsorption isotherms were employed to represent the results of the U adsorption onto the activated biochar. An estimation of the best fit was performed by calculating different deviation equations, also called error functions. The Redlich-Peterson isotherm model was the most appropriate for fitting the experimental data, suggesting heterogeneity of adsorption sites with different affinities for uranium setting up as a hybrid adsorption. These results demonstrated that physical activation significantly increases the adsorption capacity of macauba endocarp-derived biochar for uranium in aqueous solutions, and therefore open up a potential new application for this type of waste-derived biochar.
Variations in essential elements after malignant transformation of kidney epithelial tubular cells
2020 - BELLINI, MARIA H.; SOUZA, ALEXANDRE L. de; SILVA, FABIO F. da; GUILHEN, SABINE N.; FERREIRA, RAFAEL V. de P.; ARAUJO, LEANDRO G. de; OLIVEIRA, JOAO E. de; MARUMO, JULIO T.
Cell line-based research is a valuable tool for the study of cancer physiopathology and the discovery of new drugs for use in clinical practice. In this study, inductively coupled plasma mass spectrometry (ICP-MS) was used to estimate Ca, Co, Cu, Fe, K, Mg, Mn, Na, P, S, Se, and Zn in epithelial tubular cells (HK-2) and kidney tumor cells (Caki-1 cells). The most relevant difference was a decrease in the contents of Ca, Cu, Fe, K, Mg, Mn, Na, P, S, and Zn. A significant accumulation of Co was also detected in Caki-1 cells. The fold change variation of each element concentration between HK-2 and Caki-1 cells was Ca (‒0.40), Co (1.37), Cu (‒0.68), Fe (‒0.56), K (‒0.40), Mg (‒0.41), Mn (-0.54), Na (‒0.33), P (‒0.31), S (‒0.26), and Zn (‒0.73). These findings indicate that the elements mainly affect the metabolic pathways of epithelial kidney cells. Thus, our findings open a new avenue for RCC target therapy