Liquid Waste Treatment and Immobilization Using Local Geo Media

Liquid waste treatment and immobilization using local geo media. Unpublished Doctor of Philosophy dissertation, Ain Shams University, Cairo, 2014. The utilization of low cost clay materials as selective adsorbents represent one of the most effective possibilities of radionuclides and heavy metals treatment and removal from radioactive and industrial liquid waste resulting from different civil activities. This study investigated the feasibility of using the Egyptian clay minerals including Alexandria bentonite, K-95 (A-Bent), Wadii el Faregh bentonite (W-Bent) and Abu Zeneima Sina kaolin clay (S-kaol) as a low cost adsorbent for the removal of monovalent cation such as Cs (I), divalent cations represented in Co(II), Ba (II), Ni(II), Sr(II) and trivalent cation as Eu (III) from aqueous solution. to achieve the aim of the work, the conditions for adsorption, including initial metal ion concentration, ph, contact time and temperature were investigated with respect to the removal efficiency of metal ions. In addition, the evidences for physicochemical characteristics of the previous clay minerals obtained from X-ray diffraction (XRD) and scanning electron microscope (SEM), X-ray fluorescence analysis (XRF), cation exchange capacity (CEC), potentiometric titration to determine point of zero charge (PZC), digestion analysis were investigated to understand the adsorption mechanism. All physical and chemical characterization of bentonite samples show that, bentonite samples have excellent sorption properties to be used in liquid waste treatment. According to the batch experiments technique and the Langmuir , Freundlich, DubininRadushkevich (D-R), Temkin models , all cations under investigation undergo a chemisorption reaction on the clay samples and when comparison was made with other low cost adsorbent bentonite either, better or equivalent adsorption capacity was found. Kaolin has a lower activity in comparison with bentonite clay minerals and this may be due to it has no interlayer nor swelling or expansion properties. At the same time kaolin can be used because of its selective cation properties due to its porous nature. The sodium form of (A-Bent) was prepared and it used in comparison with (A-Bent) itself. It was found that (Na-Bent) is more preferred than (A-Bent) in the uptake of strontium over all range of concentrations and at lower concentrations for cobalt and cesium