Banca de DEFESA: RAYANNE MACÊDO ARANHA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : RAYANNE MACÊDO ARANHA
DATE: 17/02/2020
TIME: 09:00
LOCAL: Auditório do NUPEG I
TITLE:

Treatability studies of creosote contaminated soil applying advanced oxidative process using iron chelate activated persulfate

KEY WORDS:

Soil remediation; Advanced oxidation process; Persulfate; Creosote; Polycyclic aromatic hydrocarbons.

PAGES: 90
BIG AREA: Engenharias
AREA: Engenharia Química
SUMMARY:

A significant portion of contaminated soil contains organic liquid pollutants known as Non-Aqueous Phase Liquids (NAPLs). Creosote is a type of DNAPL (Dense Non-Aqueous Phase Liquids) and therefore has the ability to migrate to significant subsurface depths until it reaches an impermeable layer where it accumulates. Thus, it may be present at different stages in the underground medium, such as vapor, dissolved and sorbed NAPL (residual and free). It is a complex mixture of organic constituents containing mainly aromatic polycyclic hydrocarbons (HPAs). HPAs are persistent organic pollutants that tend to adsorb into solid particles due to their physicochemical properties. Advanced oxidation processes can be applied to remedy contaminated sites with HPAs through the use of oxidizing agents such as persulfate. This oxidant can be activated by iron ions generating sulfate free radicals () that react with organic species causing partial or complete mineralization. In this work, the partitioning of HPAs contained in creosote between vapor, aqueous, DNAPL and sorbed phases was evaluated. In addition, treatability assays using iron chelate activated persulphate were applied to sandy soils artificially contaminated with creosote and phenanthrene. From the phase distribution evaluation, the highest contaminant concentration was detected in the sorbed phase. Treatability trials performed on creosote contaminated soil showed that 61.4% of the PAHs selected were removed. Phenanthrene (PHE) has been shown to be one of the most recalcitrant HPAs. Thus, treatability tests on phenanthrene contaminated soil were performed and higher removal percentages were obtained and it was possible to reach levels below the intervention value established by the Environmental Company of São Paulo (CETESB) for industrial areas. Kinetic assays indicated that the degradation kinetics of PHE adequately fit a second order model. Based on the results of this study, chemical oxidation proved to be an effective remediation technology for soil contamination by HPAs.

BANKING MEMBERS:
Externo à Instituição - EDSON LUIZ FOLETTO - UFSM
Interno - 1670497 - HUMBERTO NEVES MAIA DE OLIVEIRA
Externa à Instituição - MARILDA MENDONÇA GUAZZELLI RAMOS VIANNA - USP
Presidente - 1149554 - OSVALDO CHIAVONE FILHO