الفهرس 
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Abstract
This work focused on the modification of natural attapulgite with a layered double hydroxide to produce a novel sorbent for Sr2+, Ni2+, and Co2+ removal from single and multicomponent solution system. The structural and surface characteristics of both attapulgite (ATP) and modified attapulgite (LDH-ATP) were investigated. Effect of various variables such as initial ion concentration, contact time, temperature and pH in the sorption process in single- and multi-solutions were studied and optimized. The kinetic studies indicated that the sorption is kinetically fast and reaching >90% within 30 min. The sorption of Sr2+, Ni2+, and Co2+ are well defined by non-linear pseudo-second-order model and controlled by intra-particle diffusion mechanism. The sorption equilibrium data were analyzed to evaluate the sorption characteristics and the thermodynamic parameters were calculated. Column tests were also executed to determine the design factors against the concerned ions solutions. The experimental factors influencing the removal of Sr2+, Ni2+, and Co2+ ions from aqueous solutions onto LDH-ATP and their respective levels were studied, as bed depth, A, (1≤A≤3 cm), flow rate, B, (1≤B≤3 ml/min) and initial Sr2+, Ni2+, and Co2+ ions concentration in the solution, C, (10-4 ≤C≤10-2 mol/L). These sorption factors were statistically investigated via means of analysis of variance and factorial design using Minitab software. The studies specified the feasibility of using the modified attapulgite for the removal of Sr2+, Ni2+, and Co2+ from both single and tertiary solutions due to its chemical stability, selectivity and high capacity for the concerned ions. Therefore, it is recommended to be utilized for the removal of ions from radioactive liquid waste.