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Sistemas microemulsionados aplicados ? remo??o da cor de efluente t?xtilBeltrame, Leoc?dia Terezinha Cordeiro 21 October 2006 (has links)
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Previous issue date: 2006-10-21 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Effluent color resulting from textile dyeing processes has been one of the biggest environmental problems faced by the textile industry. In particular, reactive dyes are highly resistant to conventional wastewater treatment methods. New technologies have been contemplated, some of which have been applied in industrial treatment plants, but color removal has not been efficiently attained. Since microemulsion systems provide good results in heavy metals and proteins extraction processes, their use in dyes extraction has been suggested and investigated. In this work, a real textile wastewater from an exhaustion dyebath has been treated, which contains the following reactive dyes: Procion Yellow H-E4R (CI Reactive Yellow 84), Procion Blue H-ERD (CI Reactive Blue 160) and Procion Red H-E3B (CI Reactive Red 120), in addition to auxiliary compounds normally found in dyeing processes with reactive dyes. The dyes Remazol Blue RR and Remazol Turquoise Blue G (Reactive Blue 21) have also been examined in view of the presence of heavy metals in these molecules. The microemulsion system comprised dodecyl ammonium chloride (as a cationic surfactant), water or wastewater as aqueous phase, kerosene as oil phase, and one of the following alcohols as cosurfactant: isoamyl alcohol, n-butyl alcohol and n-octyl alcohol. The pseudo-ternary diagrams were constructed in order to define Winsor s equilibrium regions. The influence of parameters such as pH, C/S (cosurfactant/surfactant) ratio, distribution coefficient, initial dye concentration, salinity, temperature, phases relative amounts, loading capacity of the microemulsion phase and dye reextraction rate has also been investigated. An experimental planning (Scheff? Net) was used to optimize the extraction process. The removal of color and metals reached levels as high as 99% / A cor do efluente resultante dos processos de tingimento tem sido um dos principais problemas ambientais enfrentados pela ind?stria t?xtil. De modo especial, efluentes contendo corantes reativos s?o altamente resistentes aos processos de tratamento convencionais. Novas tecnologias t?m sido buscadas, algumas j? em escala industrial, por?m nem sempre ? poss?vel atingir a efici?ncia desejada. Por serem utilizadas de forma eficiente em processos de extra??o de metais e de prote?nas, buscou-se utilizar as microemuls?es na extra??o de corantes. Para este estudo, um efluente real foi examinado, consistindo no banho de exaust?o de um processo de tingimento contendo os seguintes corantes: Procion Amarelo H-E4R (CI Reactive Yellow 84), Procion Azul H-ERD (CI Reactive Blue 160) e Procion Vermelho H-E3B (CI Reactive Red 120), al?m de auxiliares normalmente encontrados em processos de tingimento com corantes reativos. Para estudar a remo??o de metais ligados ?s mol?culas dos corantes, utilizaram-se ainda os corantes Remazol Azul RR e Remazol Azul Turquesa G (Reactive Blue 21). Os sistemas de microemuls?o foram formados pelo cloreto de dodecilam?nio (tensoativo cati?nico), ?gua ou efluente como fase aquosa, querosene como fase oleosa e um dos seguintes ?lcoois como cotensoativos: ?lcool isoam?lico, n-butanol e n-octanol. Os diagramas pseudo-tern?rios, representativos dos sistemas microemulsionados em estudo, foram desenvolvidos a fim de delimitar as regi?es de exist?ncia de equil?brio de fases (sistema de classifica??o Winsor). Verificou-se a influ?ncia de par?metros como: pH, raz?o C/T (cotensoativo/tensoativo), coeficiente de distribui??o, concentra??o inicial de corante, salinidade, temperatura, rela??o das fases, capacidade de carga da fase de microemuls?o e reextra??o do corante. Uma metodologia de planejamento experimental (Rede de Scheff?) foi utilizada para otimizar a extra??o. A remo??o da cor e de metais alcan?ou ?ndices de extra??o superiores a 99%
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