فهرست مطالب اعظم السادات قرقچیان

Cyanide is one of the toxins and different ways to reduce it have been studied. These include ozone oxidation methods, ultraviolet radiation degradation, alkaline chlorination, and hydrogen peroxide degradation. Each of these methods has various disadvantages and advantages, but among them, surface adsorption is an effective and efficient method. On the other hand, zeolites, which are crystalline aluminosilicate and juicy alkali and alkaline earth metals, have the ability to absorb cations and anions. To prepare a cyanide solution, it was used sodium cyanide salt based on the standard method In this work, it has been studied the adsorption of cyanide ion from aqueous solutions using zeolite nanoparticles and the factors affecting on it. In this study, the factors of the effect of the initial pH of the solution, the effect of the initial concentration of the solution, the effect of the adsorbent amount, the effect of the contact time and the effect of temperature on the surface adsorption of cyanide ions with the nano-adsorbent zeolite clinoptilolite were investigated. And after the studies, the optimal and appropriate values for each of the effective parameters pH=6, contact time 40 min, adsorbent dosage 1g/l, temperature 22°C and initial concentration of 150 mg/l. Under these optimal conditions, the highest percentage of anion cyanide uptake was obtained on the nano-adsorbent of zeolite clinoptilolite 85%. The relationship between empirical data and the equation of Langmuir, Freundlich and Tamkin equations was also investigated. The R2 values for Langmuir, Frondelich, and Temkin's alliances were 0.8337, 0.9837, and 0.99, respectively, indicating that there was a greater match between the experimental data and the Temkin temperature than the other two.

Adsorption of cyanide ion from aqueous solutions using zinc oxide nanoparticles and the affecting factors such as pH, concentration of cyanide ion, adsorbent dosage, contact time and temperature have been studied in this paper. The optimal conditions for adsorption of cyanide anion on nano zinc oxide were obtained at pH=6, contact time 80 min, adsorbent dosage 0.07g, temperature 15°C and initial concentration of 250 mg/l. Under these optimal conditions, the highest percentage of adsorption of cyanide was obtained to be 96%. Moreover, the results showed that experimental data is best fitted with Langmuir isotherm equation rather than Freundlich and Temkin isotherms. The maximum adsorption capacity obtained about 24.85 mg/g. In addition, kinetic studies showed that the adsorption of cyanide anion on nano-adsorbent zinc oxide complied well with second-order kinetics model.