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Extra??o do corante reactive blue 19 utilizando tensoativo n?o i?nico / Extraction of Reactive Blue 19 dye using nonionic surfactantMelo, Ricardo Paulo Fonseca 20 July 2012 (has links)
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Previous issue date: 2012-07-20 / The generation of effluent from the finishing process in textile industry is a serious
environmental problem and turned into an object of study in several scientific papers.
Contamination with dyes and the presences of substances that are toxic to the environment
characterize this difficult treatment effluent. Several processes have already been evaluated to
remove and even degrade such pollutants are examples: coagulation-flocculation, biological
treatment and advanced oxidative processes, but not yet sufficient to enable the recovery of
dye or at least of the recovery agent. An alternative to this problem is the cloud point
extraction that involves the application of nonionic surfactants at temperatures above the
cloud point, making the water a weak solvent to the surfactant, providing the agglomeration
of those molecules around the dyes molecules by affinity with the organic phase. After that,
the formation of two phases occurred: the diluted one, poor in dye and surfactant, and the
other one, coacervate, with higher concentrations of dye and surfactants than the other one.
The later use of the coacervate as a dye and surfactant recycle shows the technical and
economic viability of this process. In this paper, the cloud point extraction is used to remove
the dye Reactive Blue from the water, using nonionic surfactant nonyl phenol with 9,5
etoxilations. The aim is to solubilize the dye molecules in surfactant, varying the
concentration and temperature to study its effects. Evaluating the dye concentration in dilute
phase after extraction, it is possible to analyze thermodynamic variables, build Langmuir
isotherms, determine the behavior of the coacervate volume for a surfactant concentration and
temperature, the distribution coefficient and the dye removal efficiency. The concentration of
surfactant proved itself to be crucial to the success of the treatment. The results of removal
efficiency reached values of 91,38%, 90,69%, 89,58%, 87,22% and 84,18% to temperatures
of 65,0, 67,5, 70,0, 72,5 and 75,0?C, respectively, showing that the cloud point extraction is
an efficient alternative for the treatment of wastewater containing Reactive Blue / A gera??o de efluente proveniente do processo de acabamento na industria t?xtil
? um grave problema ambiental e se transformou em objeto de estudo em diversos trabalhos
cient?ficos. A contamina??o por corantes e a presen?a de subst?ncias que s?o t?xicas ao meio
ambiente caracterizam este efluente de dif?cil tratamento. V?rios processos j? foram avaliados
para remover e at? degradar tais poluentes s?o exemplos: a coagula??o-flocula??o, tratamento
biol?gico e processos oxidativos avan?ados, mas ainda n?o foram suficientes para possibilitar
a recupera??o do corante ou pelo menos do agente separador. Uma alternativa para este
problema ? a extra??o por ponto nuvem que envolve a aplica??o de tensoativos n?o i?nicos a
temperaturas acima do ponto de nuvem, tornando a ?gua um solvente fraco para o tensoativo,
proporcionando a aglomera??o destas mol?culas ao redor do corante por afinidade a fase
org?nica. Depois disso ocorre a forma??o de duas fases: uma chamada de dilu?da pobre em
corante e tensoativo e a coacervato com concentra??o de corante e tensoativo bem maior que
a outra fase. A utiliza??o posterior do coacervato como reciclo de corante e tensoativo mostra
a viabilidade t?cnica e econ?mica do processo. Neste trabalho a extra??o por ponto nuvem ?
utilizada para remover o corante Reactive Blue da ?gua utilizando tensoativo n?o-i?nico nonil
fenol com 9,5 etoxila??es. O objetivo ? solubilizar as mol?culas de corante no tensoativo,
variando-se a concentra??o deste e a temperatura para estudar seus efeitos. Avaliando a
concentra??o de corante na fase dilu?da ap?s a extra??o ? poss?vel analisar vari?veis
termodin?micas, construir isotermas de Langmuir, determinar o comportamento do volume
de coacervato para uma concentra??o de tensoativo e temperatura, o coeficiente de
distribui??o e a efici?ncia de remo??o de corante. A concentra??o de tensoativo mostrou-se
fundamental para o sucesso do tratamento. Os resultados de efici?ncia de remo??o
alcan?aram valores de 91,38%, 90,69%, 89,58%, 87,22% e 84,18% para temperaturas de
65,0, 67,5, 70,0, 72,5 e 75,0?C, respectivamente, mostrando que a extra??o por ponto nuvem
? uma alternativa eficiente para o tratamento de efluentes contendo Reactive Blue
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