A study of recovery and separation of heavy metal ions from waste solutions using precipitate flotation
- Authors: Ren, Xiang (Sean)
- Date: 1999
- Type: Text , Thesis , PhD
- Full Text: false
- Description: An important industrial problem is the production of wastewater containing a large amount of heavy metal ions. The study described in this thesis is trying to use precipitate flotation technology to explore techniques for not only removing heavy metal ions from the solution, but also selectively separating them to recycle of the recoyered metal value from industry wastewater. Zinc and copper hydroxide precipitation and flotation behaviour have been studied. lt shows that it is almost impossible to separate copper and zinc ion using hydroxide precipitate flotation when the solution contains Fe3+ or Al3+ ions. The influence of additional ions such as Ca2+ and Mg2+, and other electrolytes on the flotation and separation have been studied. DLVO theory has been used to explain the mechanisms occurring in the process. A new process, named "self-carrier" precipitate flotation us~g anionic surfactants, has been developed to improve the flotation recovery and reduce the consumption of collector. The mechanism of the process is discussed in detail with reference to data collected from Optical Microscopy, Scanning Electron Microscopy and Zeta Potential Measurement. The xanthates are the most commonly used class of sulphide mineral collectors. This study investigated the copper sulphide precipitate reactions and the aggregation behaviour, the influence of oxidation, additional ions etc., and successfully used xanthate to float the sulphide precipitates. The mechanisms occurring in this process have been discussed. The investigation of the sulphide precipitate flotation behavior using a cationic collector has also been carried out to discover the possibility of copper and zinc separation. An important application of this study is the flotation and separation of copper and zinc ions from industry wastewater. The tailing wastewater from a mineral processing plant, Woodlawn Mines (N.S.W., Australia), which contains high concentrations of harmful heavy metal ions was used to test the flotation and separation of the heavy metal ions. Both xanthate and cationic collectors have been investigated for the flotation separation. Effective separation has been achieved .
- Description: Doctor of Philosophy
A study of sulphur xanthates in relation to their role in froth flotation of sulphide minerals
- Authors: Honeyman, Ronald
- Date: 1980
- Type: Text , Thesis , Masters
- Full Text: false
- Description: Potassium alkyl xanthates are commonly used as collectors in the flotation of sulphide minerals. Much research has been directed to the formulation of mechanisms responsible for the hydrophobicity of the sulphide minerals in xanthate flotation. Alkyl dixanthogen plays an important role in this mixed-potential mechanism, and is regarded as the species which imparts hydrophobicity to the mineral surface. Winter has recently suggested that sulphur xanthates, which are chemically very similar to alkyl dixanthogen, may play a significant role in the processes rendering the sulphide minerals hydrophobic during froth flotation. The aim of this investigation was to develop techniques for the separation and identification of sulphur xanthates at very low levels of conecentration. Techniques employed were Molecular Emission Cavity Analysis Spectroscopy and High Performance Liquid Chromatography. It was possible to extract the sulpur xanthates from simulated flotation liquors, separate the individual species, and determine them to a level of 0.05 ppm in the liquor. Aklyl sulphur dixanthates were found to disproportionate in methanol solution.
- Description: Masters Degree in Applied Science
Chemistry of bis(O-ethyldithiocarbonato)cadmium(II) and flotation properties of aminodithiocarbonates
- Authors: Griffiths, Philip
- Date: 1976
- Type: Text , Thesis , Masters
- Full Text: false
- Description: Masters of Applied Science