Banca de DEFESA: JOICY RIBEIRO DOS SANTOS

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : JOICY RIBEIRO DOS SANTOS
DATE: 03/05/2022
TIME: 15:00
LOCAL: videoconferência
TITLE:

Optimization of biosorption process through factorial design for removal of Pb2+  metal ions from aquatic systems using mandacaru in natura

KEY WORDS:

Remediation, mandacaru, Cereus jamacaru, biosorption, factorial design, metal ion Pb2+

PAGES: 85
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Analítica
SPECIALTY: Análise de Traços e Química Ambiental
SUMMARY:

The search for sustainable solutions for decontamination of water by heavy metals is a topic of absolute relevance for the future of humanity, given the ability of humans and the industrial processes developed by them to pollute the environment and consequently change the natural cycle of life. In this context, studying the natural products in order to develop new methodologies of remediation, which are low cost, efficient, easy to apply and that bring fast results is a way to mitigate these environmental damages. Therefore, this research work sought to develop a cheap and accessible biosorbent for the removal of metal ions 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 (PW/OP), pulp with cover (PWP) and core (C) and used in natura. It was performed the chemical characterization of the regions 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 effect of the variables that affect the biosorption process (pH, contact time, mandacaru region and ionic strength). Using the ANOVA tool, the statistical model that best 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 solution, no NaCl addition, total time of 4h and PWP region. A remediation simulation was applied on control sample and real effluent samples of stream and sea water using the metal ion Pb2+. The removal of this contaminant was 97.3, 100 and 59.9%, for stream water, control water and sea water, 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 water contaminated with this metal ion, opening new possibilities for applications of this bioadsorbent material in in real scenarios of environmental contamination.

BANKING MEMBERS:
Presidente - 2413537 - POLLYANA SOUZA CASTRO
Interna - 1805556 - LUCIENE DA SILVA SANTOS
Externo à Instituição - ANDRÉ HENRIQUE BARBOSA DE OLIVEIRA - UFC
Externa à Instituição - SUELY SOUZA LEAL DE CASTRO - UERN