Banca de DEFESA: LUCAS LOPES SAMAGAIO

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : LUCAS LOPES SAMAGAIO
DATE: 25/09/2023
TIME: 14:00
LOCAL: https://conferenciaweb.rnp.br/webconf/wagner-27
TITLE:

Recovery of Phosphorus and Ammonium from Effluents from the Autocatalytic Deposition Process of Nickel as Struvite

PAGES: 58
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Inorgânica
SPECIALTY: Físico Química Inorgânica
SUMMARY:

Phosphorus and nitrogen are fundamental elements for use as a fertilizer in agriculture. Currently there are two problems involving these nutrients resources: its depletion, expected to occur later this century, and its presence in excessive amounts in water bodies, causing the phenomenon of eutrophication. In this context, the present work aims to recover the phosphorus and ammonium present in effluents from processes for the deposition of nickel by autocatalytic process. This effluent, due to the oxidationreduction reactions that occurs for the deposition of nickel on the surface of the desired material, has high concentrations of phosphorus species, mainly phosphite, derived from the oxidation of hypophosphite added as a reducing agent during the process. The effluent, after the removal of Ni2+, will undergo advanced oxidative processes and subsequent struvite precipitation. Thus, first the characterization of the industrial effluent was performed, followed by Ni2+ removal, reducing Ni2+ to Ni0. After nickel removal, another characterization of the effluent was performed. Based on the characteristics of the effluent, the production of phosphite was performed in order to prepare a synthetic effluent with the maximum similarity to the real industrial effluent, using the same principle of the oxidation-reduction reaction between nickel and hypophosphite. The concentration of Ni2+ showed a 99.99% reduction after the treatment. In contrast, phosphite (HPO32-) had its concentration increased by 27%. The study of phosphite production showed that nickel-catalyzed oxidation of hypophosphite also produced phosphate. At the end of the investigation, it is intended to establish appropriate procedures for obtaining struvite from the effluent, favoring its use as a fertilizer and avoiding inappropriate disposal in water bodies.

COMMITTEE MEMBERS:
Presidente - Interno ao Programa - 1601156 - WAGNER ALVES CARVALHO
Membro Titular - Examinador(a) Interno ao Programa - 1838759 - JANAINA DE SOUZA GARCIA
Membro Titular - Examinador(a) Externo à Instituição - PATRICIA ALVES CARNEIRO
Membro Suplente - Examinador(a) Interno ao Programa - 2351974 - JULIANA DOS SANTOS DE SOUZA
Membro Suplente - Examinador(a) Externo à Instituição - GABRIELA TUONO MARTINS XAVIER