Zeolites are naturally occurring aluminosilicate with several applications in many fields related to pollution control, radioactive waste management, petroleum refining, purification of gases, agriculture and others. Although, natural zeolites are not common in Egypt but bentonite sediments are. Therefore, the production of zeolites using bentonite minerals is an important issue in waste management. To convert bentonite clay to zeolitic materials, sodium hydroxide at different concentrations with two different treatments (magnetic stirring and autoclave treatments) were used. Obtained results indicated that zeolitic materials has been produced. X-ray diffraction analysis, Infra-red spectroscopy, chemical composition, cation exchange capacity and accessibility of internal sites were used to characterize the produced zeolitic materials. The nature of obtained zeolitic materials depend on the method of contact between clay and alkaline agent. Autoclave treatment showed the conversion of montomorillonite and kaolinite in the bentonite clay sediment to sodalite and analcime zeolitic materials, while magnetic stirring converted the same mineral to sodalite only when 3M NaOH was used. The CEC values of produced zeolitic materials increased with the rise in NaOH concentration until 2M, thereafter a decrease was observed for both treatment. Obtained results indicated that although ammonium is widely used to measure CEC, it seems inappropriate to apply to materials having smaller pores than the diameter of ammonium ion such as sodalite. Produced zeolitic materials have internal sites accessible to exchange with different ions and suitable to utilize in removing heavy metals or other ion toxicants from wastewater. Potentialities of produced zeolititc materials to remove heavy metals from industrial wastewater were studied as a function of contact time. The maximum percentage of metals removed was increased more than two to more than three times than initial bentonite with different arrangement of metals removed. The current study indicated that zeolitic materials produced not only had high affinity for metal ions but also had high selectivity for certain ions.

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