Agroquímica

URI Permanente desta comunidade

http://repositorio.ufes.br/handle/10/17376
Programa de Pós-Graduação em Agroquímica

Centro: CCENS
Telefone: (28) 3552 8731
URL do programa: http://www.agroquimica.alegre.ufes.br/pos-graduacao/PPGAQ

Navegar

Navegando Agroquímica por Assunto "Adsorção de cromo hexavalente"

Agora exibindo 1 - 1 de 1
  • Nenhuma Miniatura disponível
    Item
    Adsorção de cromo hexavalente por hidróxido de alumínio amorfo em meio aquoso: isotermas e termodinâmica
    (Universidade Federal do Espírito Santo, 2022-02-15) Oliveira, Sara de Jesus; Burak, Diego Lang; https://orcid.org/0000000267583517; http://lattes.cnpq.br/2501042964619476; https://orcid.org/0000000271299690; http://lattes.cnpq.br/4230219901556586; Anastácio, Simone Aparecida Fernandes; https://orcid.org/0000-0002-7030-6748; http://lattes.cnpq.br/0532528200582514; Neves, Mirna Aparecida; http://lattes.cnpq.br/4696981882395783
    The presence of potentially toxic metals in the environment lethally affects the ecosystem, which means that environmental responsibility actions have being developed in order to minimize the damage caused by those elements. Therefore, this study has been evaluated the removal of hexavalent chromium by amorphous aluminium hydroxide in aqueous media under experimental temperature conditions of 25, 45 and 55 °C, and concentrations of adsorbate ranging from 30 to 300 mg L -1 . The adsorbate has been synthesized by the precipitation method, and characterized by the diffuse reflectance in near infrared (NIR) method, obtaining three significant peaks that described the product. By using partition coefficient (Kp), it was possible to establish the saturation point on the adsorbate active sites. The equilibrium isotherms, based on the determination coefficient (R2 ) indicated the adjustment order: Sips> RedlichPeterson> Koble-Corregan> amorphous aluminium hydroxide Langmuir> Jovanivich> Freundlich. The negative values of (∆G°) and enthalpy (∆H°) indicated that the reaction is spontaneous and the process is exothermic, respectively. The maximum adsorption capacity (qmax) of the amorphous aluminium hydroxide was 77,52 mg g-1 , which proves the removal efficiency in the hexavalent chromium in aqueous media.