| Name: | Description: | Size: | Format: | |
|---|---|---|---|---|
| 4.48 MB | Adobe PDF |
Advisor(s)
Abstract(s)
O trabalho desenvolvido teve como objetivo realizar simultaneamente a oxidação
eletroquímica tridimensional de compostos orgânicos adsorvidos no Polímero de Líquido
Iónico poli(dialildimetilamónio) bis(trifluorometanossulfonil)imida e efetuar a sua
regeneração eletroquímica. Utilizou-se os corantes têxteis Reactive Blue 5 e Direct Red
80 como compostos orgânicos modelo e os fármacos diclofenac e ibuprofeno.
O estudo envolveu a degradação dos compostos orgânicos via oxidação
eletroquímica bidimensional e tridimensional, como também a regeneração eletroquímica
do polímero. Em condições otimizadas, recuperações superiores a 84,98 % foram obtidas
após 2 ciclos. Essas condições incluem um volume de solução de 35 mL, rácio de
polímero de 1 mg/mL, diferença de potencial de 5 V, ânodo e cátodo de Mixed Metal
Oxide e aço inoxidável, respetivamente, e 0,04 M de NaCl como eletrólito suporte.
O processo de regeneração eletroquímica leva a uma diminuição na capacidade de
adsorção dos corantes no polímero. Estima-se que a oxidação eletroquímica possa ter um
papel fundamental na diminuição da capacidade de adsorção do polímero após cada ciclo.
Pelo polímero em estudo ser um composto de estrutura catiónica,
preferencialmente compostos aniónicos adsorvem, como os corantes têxteis modelo e os
fármacos diclofenac e ibuprofeno, indicando que a adsorção ao polímero é efetuada por
atração eletrostática.
Comparando a oxidação bidimensional e tridimensional, verificou-se que o
polímero em estudo não funciona como um elétrodo particulado ideal uma vez que não
degrada eficientemente ou mais rapidamente os compostos orgânicos usados neste
estudo.
Concluindo, é possível remover os corantes têxteis (Reactive Blue 5 e Direct Red
80) e os fármacos (diclofenac e ibuprofeno) de soluções aquosas através da adsorção no
poli(dialildimetilamónio) bis(trifluorometanossulfonil)imida e proceder de seguida à sua
regeneração eletroquímica. No entanto, a oxidação eletroquímica tridimensional,
relativamente à oxidação eletroquímica bidimensional não parece ser mais eficiente.
The objective of this work was to simultaneously perform three-dimensional electrochemical oxidation of organic compounds adsorbed on the Polymeric Ionic Liquid poly(diallyldimethylammonium) bis(trifluoromethanesulfonyl)imide and to perform its electrochemical regeneration. The textile dyes Reactive Blue 5 and Direct Red 80 were used as model organic compounds, along with the pharmaceuticals diclofenac and ibuprofen. The study involved two-dimensional and three-dimensional electrochemical oxidation for the degradation of the organic compounds, as well as the electrochemical regeneration of the polymer. Under optimized conditions, recoveries higher than 84,98 % were obtained after 2 cycles. These conditions included a solution volume of 35 mL, polymer ratio of 1 mg/mL, a potential difference of 5 V, anode and cathode of Mixed Metal Oxide and stainless steel, respectively, and 0,04 M of NaCl as the supporting electrolyte. The electrochemical recovery process leads to a decrease in the polymer's adsorption capacity for the dyes. It is estimated that electrochemical oxidation may play a fundamental role in this decrease after each cycle. Since the polymer in this study has a cationic structure, predominantly anionic compounds are adsorbed, such as the model textile dyes and the pharmaceuticals diclofenac and ibuprofen, this indicates that adsorption in this polymer occurs via electrostatic interactions. Comparing the two-dimensional and three-dimensional oxidation, it was found that the polymer under study does not function as an ideal particulate electrode because it does not degrade organic compounds efficiently or quicky in this work. In conclusion, it is possible to remove the textile dyes (Reactive Blue 5 and Direct Red 80) and the pharmaceuticals (diclofenac and ibuprofen) from aqueous solutions through adsorption on poly(diallyldimethylammonium) bis(trifluoromethanesulfonyl)imide and proceed its electrochemical recovery. However, compared to two-dimensional electrochemical oxidation, a three-dimensional electrochemical oxidation system does not appear more efficient.
The objective of this work was to simultaneously perform three-dimensional electrochemical oxidation of organic compounds adsorbed on the Polymeric Ionic Liquid poly(diallyldimethylammonium) bis(trifluoromethanesulfonyl)imide and to perform its electrochemical regeneration. The textile dyes Reactive Blue 5 and Direct Red 80 were used as model organic compounds, along with the pharmaceuticals diclofenac and ibuprofen. The study involved two-dimensional and three-dimensional electrochemical oxidation for the degradation of the organic compounds, as well as the electrochemical regeneration of the polymer. Under optimized conditions, recoveries higher than 84,98 % were obtained after 2 cycles. These conditions included a solution volume of 35 mL, polymer ratio of 1 mg/mL, a potential difference of 5 V, anode and cathode of Mixed Metal Oxide and stainless steel, respectively, and 0,04 M of NaCl as the supporting electrolyte. The electrochemical recovery process leads to a decrease in the polymer's adsorption capacity for the dyes. It is estimated that electrochemical oxidation may play a fundamental role in this decrease after each cycle. Since the polymer in this study has a cationic structure, predominantly anionic compounds are adsorbed, such as the model textile dyes and the pharmaceuticals diclofenac and ibuprofen, this indicates that adsorption in this polymer occurs via electrostatic interactions. Comparing the two-dimensional and three-dimensional oxidation, it was found that the polymer under study does not function as an ideal particulate electrode because it does not degrade organic compounds efficiently or quicky in this work. In conclusion, it is possible to remove the textile dyes (Reactive Blue 5 and Direct Red 80) and the pharmaceuticals (diclofenac and ibuprofen) from aqueous solutions through adsorption on poly(diallyldimethylammonium) bis(trifluoromethanesulfonyl)imide and proceed its electrochemical recovery. However, compared to two-dimensional electrochemical oxidation, a three-dimensional electrochemical oxidation system does not appear more efficient.
Description
Keywords
Polymeric Ionic Liquid Three-Dimensional Oxidation Electrochemical Regeneration Poly(dialyldimethylammonium) Bis(trifluoromethanesulfonyl)imide Direct Red 80 Reactive Blue 5 Diclofenac Ibuprofen Polímeros de líquidos iónicos Oxidação tridimensional Regeneração eletroquímica Poli(dialildimetilamónio) Bis(trifluorometanossulfonil)imida Direct Red 80 Diclofenac Ibuprofeno