Banca de DEFESA: ARYANDSON DA SILVA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : ARYANDSON DA SILVA
DATE: 27/02/2023
TIME: 14:00
LOCAL: Auditório do CCET
TITLE:

Synthesis of LTA zeolites for CO2 adsorption

KEY WORDS:

CO2 adsorption; synthesis; residue; selectivity; LTA zeolite

PAGES: 140
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Inorgânica
SPECIALTY: Determinação de Estrutura de Compostos Inorgânicos
SUMMARY:

Currently, CO2  is the main gas that causes the greenhouse effect, mainly because it is easily obtained in combustion processes, which is the main form of energy conversion used by humanity and the amount of gas emitted into the atmosphere has increased over time. of the years, therefore, studies that aim to mitigate or end emissions are increasingly present in the scientific community. LTA zeolites synthesized from different silicon sources were then compared, cation exchange was performed on these materials, they were then characterized by x-ray diffraction (XRD), X-ray fluorescence (XRF), analysis of textural properties by adsorption and argon desorption at 77K and then applied to CO2 adsorption at low pressures up to 10 atm at room temperature, compared with model isotherms by Langmuir, Freundlich and Temkin and the best results applied to more extreme conditions, from 5 bar to 25 bar at 200°C, and selectivity tests were carried out in a fixed bed column, with a gaseous mixture of CO2/CH4. From the XRD it was possible to observe the formation of the crystalline phases characteristic of the LTA zeolite, and analyzing the argon adsorption and desorption isotherms it was possible to confirm the cation exchange process by the considerable increase in the specific area and volume of micropores. This increase significantly influenced the adsorption of CO2, as it was possible to observe by the isotherms, where the materials containing calcium absorbed a greater amount than the materials in sodium form. When applied under extreme conditions of temperature and pressure, we see that the materials continue to adsorb with increasing pressure, even at temperatures of 200°C and from the selectivity study, we see that all materials showed good selectivity for CO2, in the CO2/CH4 mixture, adsorbing more than 99% of CO2 and less than 1% of CH4 in 10 minutes.

COMMITTEE MEMBERS:
Externo à Instituição - ADONAY RODRIGUES LOIOLA - UFC
Externo à Instituição - FABIO GARCIA PENHA - IFRN
Interna - 1805556 - LUCIENE DA SILVA SANTOS
Externa à Instituição - MARIELE IARA SOARES DE MELLO - UFRN
Presidente - 1308577 - SIBELE BERENICE CASTELLA PERGHER