Graduate Thesis Or Dissertation
 

Preparation and laboratory evaluation of stationary-phase iron-oxide-based adsorbents for removal of metals from waste waters

Público Deposited

Contenido Descargable

Descargar PDF
https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/h415pd706

Descriptions

Attribute NameValues
Creator
Abstract
  • Several potential sorbent materials containing iron oxides were prepared and evaluated for potential to remove divalent metals from waste waters. These included a ferrihydrite-coated sand, maghemite incorporated in Dowex[Trademark] ion exchange resin, gothite and two thermally activated ferrihydrites. Attempts to prepare sorbents from steel shot by coating with ferrihydrite or by thermal oxidization resulted in cemented solids rather than pellets. Ferrihydrite activated at 295°C had a surface area of 113-202 m²/g, followed by gothite at 72-92 m²/g and ferrihydrite-coated sand at 0.78-1.4 m²/g. Zinc adsorption was evaluated by placing 5 g ferrihydrite-coated sand, 0.1 g maghemite in Dowex or 0.1 g gothite in batch reactors containing 40-50 mL of zinc solution, adjusting to various pH values, allowing to react for 96 hours, and analyzing the supernatant for zinc. The data fitted poorly to an ion exchange model using nonlinear regression. The adsorption site densities determined from the regression analysis were 8.0x10⁻⁸ moles per gram of ferrihydrite-coated sand and 4.1x10⁻⁵ moles per gram of White. Maghemite in Dowex did not provide any additonal zinc removal capacity in excess of the ion exchange capacity of the resin. Kinetic experiments showed that zinc adsorption onto ferrihydrite-coated sand was 86% complete after 96 hours. Based upon this study, the most promising sorbent appears to be gothite, although the "activated ferrihydrites" are also worthy of further study. Neither ferrihydrite-coated sand and maghemite in Dowex appear to be practical sorbents, based on their low zinc adsorption site density. Maghemite in Dowex might be useful in applications requiring magnetic sorbents.
License
Resource Type
Fecha Disponible
Fecha de Emisión
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Academic Affiliation
Non-Academic Affiliation
Subject
Declaración de derechos
Publisher
Peer Reviewed
Language
Digitization Specifications
  • File scanned at 300 ppi (Monochrome, 24-bit Color) using ScandAll PRO 1.8.1 on a Fi-6670 in PDF format. CVista PdfCompressor 4.0 was used for pdf compression and textual OCR.
Replaces

Relaciones

Parents:

This work has no parents.

En Collection:

Elementos

Miniatura Título Fecha de subida Visibilidad Acciones
file details MayMichaelLee1999.pdf 2017-08-15 Público Descargar