الفهرس 
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Abstract
The problem of water and soil pollution is one of the most substantial problems that recent studies are interested in finding solutions to due to the environmental and health hazards it causes. This study aims to synthesize zeolite from low-cost materials as clay mineral (kaolin) which is widely available in Wadi Hajoul - Suez – Egypt. Synthetic zeolite has many characteristics; high purity and larger cavities that identify it from its counterparts which increases the efficiency of the adsorption process for heavy metals. The synthesized zeolite is characterized by different spectroscopic techniques XRD, XRF, SEM, and IR. Also, the concentration of heavy metals was analyzed by the ICP technique. The Cation Exchange Capacity (CEC) showed a high value of 401.09 meq/100 g clay for synthesized zeolite. Through the process of hydrothermal calcination (metakaolinization) of raw material (kaolin) at 800oC for 6 hours. The amorphous phase (metakaolinite) appeared at 24 hours. Metakaolinite was treated under hydrothermal with 1.0 M NaOH solution without additional catalysts as a silica source at 90oC/2d under atmospheric pressure to produce the zeolite crystals. Crystallization times of 48 hours created zeolite type Y. The concentrations of heavy metals in the solutions before and after treatments with adsorbent materials have followed at different times and concentrations. The three kinetic parameters for pseudo-first-order (PFO), pseudo-second-order (PSO), and intra-particle diffusion (IPD). Removal of heavy metals can be described by Langmuir, Freundlich, and Harkins-Jura sorption isothermal models to evaluate the adsorption behavior of synthetic zeolite, natural zeolite, and kaolin.SEZ, NZ, and EK were applied to estimate the mechanism of fixation of heavy metals in soil treatment. Eruca sativa was grown in contaminated soils in pots (split-plot under completely randomized). In addition, the heavy metal concentrations, physical, and chemical properties of soil were evaluated before and after cultivation. The results’ mean values of heavy metals determine at a significant level (P< 0.05) using statistical analysis (SAS) to separate the differences between the treatments and the control. According to the results, the SEZ was more sensitive to retaining Cd2+, Pb2+, and Zn2+ but had a low sensitivity to retaining Zn2+. The removal efficiency for the adsorbents in the single solution were (100٪ for Pb2+, 99.93 for Cd2+, and 99.86٪ for Zn2+ when using SEZ, (99.88٪ for Pb2+, 28.44٪ for Cd2+ , and 09.92٪ for Zn2+ by NZ, and (100٪ for Pb2+, 83.90٪ for Cd2+, and 73.15٪ for Zn2+ when using EK . While the removal efficiency for the adsorbents in the ternary solutions were (100٪ for Pb2+, 99.91٪ for Zn2+, and 98.99٪ for Cd2+ by SEZ, 94.09٪ for Pb2+ and less than 5٪ for Cd2+, and Zn2+ by NZ, and 90.14٪ for Pb2+, 16.84 for Cd2+, and 19.53٪ for Zn2+ when using Ek. The Langmuir isotherm model was significantly more favorable for the experimental data for evaluating the adsorption behavior of the three adsorbents. The results showed that the ability of the adsorbents to remove heavy metals increases with increasing contact time and that the PSO is the best for describing adsorption rates. In the case of applying the adsorption experiment in industrial wastewater, the sorption efficiency values ranged (from 99.40٪ - 95.42٪) for SEZ, (98.30٪ - 78.89٪), (96.56٪ to 49.59٪) for NZ, and the EK respectively. Addition rates of 3٪ and 5٪ for SEZ were very suitable to significantly reduce heavy metal concentration in contaminated soil and bioavailability of heavy metals in shoots of Eruca sativa plants, while NZ and EK required 10٪ to obtain the same effect. Finally, the results confirmed that the Na-Y zeolite was successfully synthesized from kaolin extracted from Wadi Hajoul with a molar ratio for Al/Si 2.23 and an ideal ratio equal to almost 100٪ of the raw material (kaolin) used. Synthetic zeolite was preferred and more efficient than natural zeolite and kaolin for the treatment of wastewater and contaminated soil.