Synthesis, characterization and application of analcime to control nitrate ions from the ground water samples from Wadi El-Assiuti – Egypt as a low-cost and locally available adsorbent

Abstract

Abstract In this study, the sorption behavior of synthetic (Analcime) zeolites with respect to nitrate ions has been studied in order to consider its application to purity ground water. Analcime or also can be called analcite (“weak”) is a kind of grey, white or colorless tectosilicates minerals. It is hydrated sodium aluminum silicates which exist in cubic form in crystalline. Analcime was successively synthesized from kaolinite as a raw material using the fusion with NaOH method. The conditions of hydrothermal crystallization (zeolitization) were found to be at temperature of 170 C˚, and time span between 36 h and 72 h for kaoline with the molar composition of 6Na2O: 0.75Al2O3:30SiO2. 780H2O.The synthetic materials have been characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), thermo gravimetric (DTA/TGA) analysis and Surface area and porosity of synthesized analcime .The results indicate that the crystallization of analcime not affected by the hydrothermal reaction time. Also analcime was tested as adsorbents for the removal of nitrate ions from the ground water samples from Wadi El-Assiuti – Egypt .The adsorption capacities of nitrate ions by analcime, as a function of its concentration, were determined at room temperature by varying analcime concentration for each water samples. During the process, all the other parameters (pH and contact time) were kept constant with respect to the initial concentration of nitrate ions in the water samples. It was found analcime has good removal efficiency obtained at pH 6-7.6, adsorbent dosage 10-12 g/L, and contact time 60 min. The Langmuir constants model for NO3 − ion sorption on the adsorption isotherms is fitted well. The RL value in the present investigation was equal or less than one, indicating that the adsorption of NO3 −ion by analcime is favorable.