Otimização do processo de biossorção através do planejamento experimental para remoção de íons metálicos Pb2+ de sistemas aquáticos utilizando mandacaru in natura

• Ano de defesa: 2022
• Autor(a) principal: Santos, Joicy Ribeiro dos
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal do Rio Grande do Norte; Brasil; UFRN; PROGRAMA DE PÓS-GRADUAÇÃO EM QUÍMICA
• Palavras-chave em Português: Química; Remediação; Mandacaru; Biossorção; Cereus jamacaru; Planejamento experimental; Íon metálico Pb2+
• Link de acesso: https://repositorio.ufrn.br/handle/123456789/47533

The search for sustainable water decontamination solutions is a topic of absolute relevance for the future, given the ability of humans and the industrial processes developed by them to pollute the environment changing the natural cycle of life. In this context, natural products investigations to develop new remediation methodologies, which are low cost, efficient, easy to apply bringing fast results is a way to mitigate these environmental damages. Therefore, this research sought to develop a cheap and accessible biosorbent for the metal ions removal using a native plant species of the caatinga, Cereus jamacaru, popularly known as mandacaru. The mandacaru stems were divided in three regions denominated pulp without cover, pulp with cover and core used in natura. It was performed the regions chemical characterization by Fourier transform infrared spectrometry (FTIR) and quantification of total carbohydrates, soluble proteins and phenolic compounds in the aqueous extract. After the preliminary test of biosorption, a factorial design was applied with the objective to evaluate and optimize the variables affects the biosorption process (pH, contact time, mandacaru region and ionic strength). Using the ANOVA tool, the best model that fitted the data was the statistically significant and predictive model with the correlation coefficient of R2 of 0.9031, R-adj of 0.8243 and p < 0.05, with pH 5, without NaCl addition, total time of 4h and pulp with cover region. A remediation simulation was applied on control sample and real effluent samples of stream and sea water with removal of 100, 97.3 and 59.9%, respectively. The adjustment to the pseudo-second order kinetic model suggests chemisorption as the determining process for biosorption. Thus, we can conclude that the mandacaru regions demonstrated potential capacity to remediate contaminated water, opening up new possibilities for bioadsorbent applications in real scenarios of environmental contamination.