Determination of contact angles of powders by capillaric dewatering of filter cakes

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2005

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Eratak, Özlem Deniz

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Solid-liquid contact angle is an important parameter in many particulate processes of the mineral, ceramic and chemical industries. In particular, modification of the contact angle through surface active agents plays a crucial role in froth flotation of minerals. In the case of flat solid surfaces, direct measurement of the contact angle is possible. However, such flat surfaces can not be obtained with finely divided solids typically encountered in flotation applications. Then, indirect methods based on powder beds as thin layers of powders deposited on glass plates or packed columns are used for the determination of apparent contact angles. This thesis presents an alternative novel method based on the capillaric dewatering of filter cakes for the measurement of the receding contact angle and correlates the contact angles measured as such with column wicking and micro-flotation test results of zircon and rutile mineral particles. The experimental procedure is simple and fast. The results have proven that the proposed method is reliable and give a good measure of the contact angle in the absence and presence of surface active non-wetting agents.

Subject Keywords

Surface chemistry.

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http://etd.lib.metu.edu.tr/upload/12605901/index.pdf
https://hdl.handle.net/11511/14804

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

Ö. D. Eratak, “Determination of contact angles of powders by capillaric dewatering of filter cakes,” M.S. - Master of Science, Middle East Technical University, 2005.