Skip to Main Content
Skip Nav Destination
GEOREF RECORD

Quantification of hematite and goethite concentrations in kaolin using diffuse reflectance spectroscopy; a new approach to Kubelka-Munk theory

Italo Gomes Goncalves, Carlos Otavio Petter and Jaqueline Lepkoski Machado
Quantification of hematite and goethite concentrations in kaolin using diffuse reflectance spectroscopy; a new approach to Kubelka-Munk theory
Clays and Clay Minerals (October 2012) 60 (5): 473-483

Abstract

Kaolin ores are usually contaminated by some Fe-bearing minerals, the strong colors of which degrade the quality of the final product. A spectroscopic technique is sought to quantify the content of hematite and goethite, the main contaminant minerals in the kaolin from Capim River in Brazil, was the focus of this study. The total Fe content obtained through X-ray fluorescence showed a poor correlation with the brightness of kaolin, due to the inability to differentiate between the Fe contained in the (oxyhydr)oxides and the Fe present in the crystalline structure of kaolinite, especially when the Fe-bearing minerals occur in small quantities. Here, a new generic technique to quantify Fe (oxyhydr)oxides in kaolin, based on the Kubelka-Munk theory, is presented. A new interpretation of the theory was made that enables its use without the need to measure thin layers of material. The results with synthetic goethite and hematite were very positive (R (super 2) (sub pred) nearly equal 0.99) and experiments with contaminants from the mine are already underway.


ISSN: 0009-8604
EISSN: 1552-8367
Coden: CLCMAB
Serial Title: Clays and Clay Minerals
Serial Volume: 60
Serial Issue: 5
Title: Quantification of hematite and goethite concentrations in kaolin using diffuse reflectance spectroscopy; a new approach to Kubelka-Munk theory
Affiliation: Universidade Federal do Rio Grande do Sul, Departamento de Engenharia de Minas, Laboratorio de Processamento Mineral, Rio Grande do Sul, Brazil
Pages: 473-483
Published: 201210
Text Language: English
Publisher: Clay Minerals Society, Chantilly, VA, United States
References: 20
Accession Number: 2013-009611
Categories: Sedimentary petrology
Document Type: Serial
Bibliographic Level: Analytic
Illustration Description: illus. incl. 3 tables
S34°00'00" - N05°15'00", W74°00'00" - W34°00'00"
Country of Publication: United States
Secondary Affiliation: GeoRef, Copyright 2017, American Geosciences Institute. Abstract, Copyright, Clay Minerals Society. Reference includes data from GeoScienceWorld, Alexandria, VA, United States
Update Code: 201307
Close Modal

or Create an Account

Close Modal
Close Modal