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The massive scale of industrial development has resulted in environmental pollution in general and water contamination in particular. It is important at the present time to treat water for the purpose of eliminating or reducing pollutants, especially toxic pollutants, such as phenol compounds. In this study, zeolite (4A) was prepared firstly from the available and cheap materials using an inclined rotary disk. Then, physical, mechanical, and chemical properties were also studied. Experiments were conducted to determine these properties using local clay and the following results were obtained: Zeolite (4A) 70% and clay 30%, the time of calcination 3 h at a temperature of 850��C, breakage resistance of 17 Ib pounds, surface area 530-590 m2/g, grinding value 14% and moisture absorption ratio 30%. The prepared zeolite (4A) was used in the process of removing phenolic compounds (chlorophenol, nitrophenol) by the adsorption method. Different amounts of prepared zeolite (5g/l and 10g/L) will be used in the treatment process and different concentrations (2mg/L, 5 mg/L and 10 mg/L) of the pollutants Nitrophenol and Chlorophenol were used in the contaminated water tested. The removal process was carried out with a mixing speed of 200 rpm and pH (7.5-8.5). From the results of this study, we note that the highest percentage of Nitrophenol removal is (84.8%) when using an amount of zeolite (5g) and highest percentage of Nitrophenol removal is (95.5%) when using an amount of zeolite (10g) while that the highest percentage of Chlorophenol removal is (78.3%) when using an amount of zeolite (5g) and highest percentage of Chlorophenol removal is (0.894) when using an amount of zeolite (10g) it could be deduced that the percentage of the removal of nitrophenol was higher than that of chlorophenol because its solubility of chlorophenol in water is higher than the solubility of Nitrophenol.

Since their discovery in 1958, atrazine and other members of s-triazine family have been extensively applied in order to control grassy and broadleaf weeds in crops. Although, it was proved by many researchers that atrazine was slow and partially degradable material. These pesticides were widely used to enhance crop quality and yield. Atrazine degradation can be achieved by the effects of air, sun, water, microorganisms and temperature. Thermal degradation plays an important role in agrochemicals elimination; so a better understanding of the role of thermal degradation of atrazine is essential. Quantitative determination of pesticide residues was studied by calculating the amount of herbicide residues left after decomposition using a simple thermo analytical technique (TG, DSC). In this study, we found that all samples undergo the process of melting, evaporation, decomposition and oxidation at a temperature higher than the maximum registered climate temperature which made us conclude that 80–90%wt) of the pesticides stay in the environment without change under 100 °C on different parts of plants like fruits, leaves, and some penetrate into the ground to reach the roots or continue to the groundwater causes toxic problems to their consumers and environmental pollution. This result gave the motivation to find a more effective approach to reduce the harmful effect of these pollutants. In this regard, biological degradation of atrazine by using two legumes roots rhizobium bacteria was investigated. It is found that both rhizobium are able to treat atrazine at moderate temperature (30 °C). In comparison to chickpea rhizobia, bean rhizobia showed a higher performance with a removal efficiency of 43.21% and 57.42% at mild and high atrazine concentrations (5 mg/L and 10 mg/L) respectively. The results from this research offer an elegant way to remove the harmful effect of herbicides through degradation and to bring the safe use of herbicides a step closer to applications.

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