ETD Collection

Permanent URI for this collectionhttps://wiredspace.wits.ac.za/handle/10539/104


Please note: Digitised content is made available at the best possible quality range, taking into consideration file size and the condition of the original item. These restrictions may sometimes affect the quality of the final published item. For queries regarding content of ETD collection please contact IR specialists by email : IR specialists or Tel : 011 717 4652 / 1954

Follow the link below for important information about Electronic Theses and Dissertations (ETD)

Library Guide about ETD

Browse

Filters

20101

Settings

Author: search.filters.author.Kapanji, Kutemba Kaina

Search Results

Now showing 1 - 1 of 1
  • No Thumbnail Available
    Item
    The removal of heavy metals from wastewater using South African clinoptilolite
    (2010-04-09T06:47:52Z) Kapanji, Kutemba Kaina
    This research concerns the further characterisation and establishment of adsorption behaviour of the South African clinoptilolite. Synthetic single- and multi-component wastewaters were used, and experiments conducted in both batch and column systems at 25oC ± 2. Wastewaters containing heavy metals ions Cu2+, Co2+, Ni2+ and Cr3+, were used at different feed concentrations (50 - 500 mg/L), and adsorbed onto natural and homoionic (Na+, K+, Ca2+, NH+ 4) forms of the zeolite. The Na+-form clinoptilolite had an improved cation exchange capacity over the natural one, and the selectivity series of metal ions by these two forms varied. Brunauer Emmett Teller surface area analysis carried out also confirms that preconditioning clinoptilolite with Na+ ions results in an increase in pore diameter, allowing for easier diffusion of ions and more adsorption. An atomic adsorption spectrophotometer (AAS) was used to analyse metal ions in solution. Adsorption efficiencies with over 75% of metal ions adsorbed in the first hour of contact were recorded, and complete adsorption equilibrium being reached in 4 hrs. Regeneration of Na+-form and natural clinoptilolite (using 0.5M NaCl stripping solution) initially showed an increase in loading capacities, then a decrease with the subsequent cycles. A comparison between two particle sizes revealed that smaller particle sized clinoptilolite have slightly higher adsorption capacities. The equilibrium data also fitted well with the linear form of the Langmuir and Freundlich isotherms at lower concentrations of 50 mg/L.