Change search
ReferencesLink to record
Permanent link

Direct link
Adsorption of heptyl xanthate at the metal sulphide/aqueousinterface
2004 (English)Licentiate thesis, comprehensive summary (Other academic)
Abstract [en]

In sulphide mineral flotation a sufficient hydrophobicity of the mineral surfaces is obtained by the adsorption of collector chemicals at the metal sulphide/aqueous interface. This surface alteration is of fundamental and applied interest. In this thesis, attenuated total reflection infrared spectroscopy has been used to monitor the adsorption kinetics and the orientation of heptyl xanthate when adsorbed onto three solid surfaces - germanium, zinc sulphide and lead sulphide in-situ. The choice of using the ATR technique is because it is very suitable when working with water as solvent, and the choice of germanium as internal reflection element is because of its small penetration depth due to a high refraction index. The Chemical Bath Deposition method has been used to deposit metal sulphides onto germanium internal reflection elements. For determining the adsorption of heptyl xanthate onto lead sulphide a novel method has been tested, and verified as capable in recovering information about surface reactions at a lead sulphide/aqueous interface. In the study of surface reactions the substrate is of vast importance, implying that the chemistry of the surface has to be well characterised. This work has utilized X-ray Photoelectron spectroscopy, and ATR spectroscopy, in the characterisation of the different surfaces. The adsorption kinetics has been followed to adsorption equilibrium at different concentrations. In the case of heptyl xanthate adsorbed at the zinc sulphide/aqueous interface, an adsorption isotherm has been calculated from the equilibrium data. On the assumption that the adsorption step was rate controlling a second order rate equation was derived and adsorption rate data tested according to this equation. In addition, an orientation study of the heptyl xanthate molecule at the different interfaces was performed, which requires polarised infrared light. In the case of heptyl xanthate adorbed onto germanium, both surface excess and a degree of alignment of the alkyl chain from the surface normal has been calculated.

Place, publisher, year, edition, pages
Luleå: Luleå tekniska universitet, 2004. , 44 p.
Licentiate thesis / Luleå University of Technology, ISSN 1402-1757 ; 2004:01
Research subject
Chemistry of Interfaces
URN: urn:nbn:se:ltu:diva-16791Local ID: 00954260-adfb-11db-879f-000ea68e967bOAI: diva2:989778
Godkänd; 2004; 20070127 (ysko)Available from: 2016-09-29 Created: 2016-09-29Bibliographically approved

Open Access in DiVA

fulltext(27684 kB)0 downloads
File information
File name FULLTEXT01.pdfFile size 27684 kBChecksum SHA-512
Type fulltextMimetype application/pdf

Search in DiVA

By author/editor
Fredriksson, Andreas

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

ReferencesLink to record
Permanent link

Direct link