Banca de QUALIFICAÇÃO: JOÃO GABRIEL BEZERRA COSTA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : JOÃO GABRIEL BEZERRA COSTA
DATE: 13/03/2020
TIME: 13:30
LOCAL: Sala do CATRE
TITLE:

Active carbon from textile waste: synthesis, characterization and application reactive dye removal from a synthetic wastewater. 

KEY WORDS:

 

 textile wastewater, removal of color, waste cotton fiber (RFA), adsorption, activated carbon (CAT)

 

PAGES: 83
BIG AREA: Engenharias
AREA: Engenharia Química
SUMMARY:

The textile industry demands an enormous amount of water resources, thence generates large volumes of wastewater with a high polluting potencial. Among these contaminants, textile dyes, since they give color to recipiente bodies, appear to have a distinctive role in the environmental approach. Regarding this, the presente work proposes a cyclical reuse of the solid textile waste, whose usual destinations point to low added value products, for the synthesis of activated carbon and removal of dyes from textile wastewater. Therefore, 100% cotton fibers (RFA), which are the main natural matrix of the textile industry, were used. The RFA was impregnated with H₃PO₄and pyrolysed in a vertical tubular oven at a rate of 5 °C/min and remained for 3 h at 500 ° C under N_2(g) flow, obtaining the activated carbon (CAT). A commercial activated carbon (CAC) was used as a direct comparison parameter. The RFA showed low fixed carbon content (C_fixo= 2.98%), semicrystalline structure (IC = 77.88%) of type Iα cellulose and flat twisted ribbon morphology with no pores on its surface. On the other hand, RFA+H₃PO₄showed an increase in its stability and carbon availability for the synthesis of activated carbon by the appearance of phosphate bridges that promoted crosslinking of cellulose chains, resulting in a satisfactory pyrolysis yield (η_pir= 60,145 %). CAT and CAC coals showed irregular morphologies, amorphous structures and close isoelectric points (pH_iso= 2.62 and 2.29, respectively), with CAT showing good textural properties (S_BET=1096 m²/g; V_TP= 0.81 cm³/g; d_Pm= 1.5) when compared to CAC and others reported in the literature. The adsorption tests reached a maximum removal of 75.41% and 65.36% for CAT and CAC, respectively, in 12 h. Both systems fitted better to pseudo second order kinetic model (R²_CAT= 0.99518 and R²_CAC= 0.99746) with k₂,_CAT= 2194.16336 g/mg*min and k_2,CAC= 2194.16336 g/mg*min. The equilibrium isotherm data denoted a physical and favorable adsorption process with maximum adsorption capacities of q_max,CAT= 131.23844 mg/g and q_max,CAC= 58.91475 mg/g. A better fit was obtained for the Freundlich model for CAT (R²= 0.9908) and for Langmuir for CAC (R²= 0.999917).

BANKING MEMBERS:
Presidente - 2929066 - ANDRE LUIS LOPES MORIYAMA
Externa ao Programa - 1415657 - ANDREA OLIVEIRA NUNES
Externa ao Programa - 1415919 - KATHERINE CARRILHO DE OLIVEIRA
Externa ao Programa - 2668814 - MAGNA ANGELICA DOS SANTOS BEZERRA SOUSA