Document Type : Research Paper

Authors

• S Sadeghi
• M Rabbani
• M Khosravi
• F Ahari Hashemi
• I Bayat

Abstract

In this research, adsorption of molybdenum has been investigated by a new silica aerogel. This hydrophobic silica aerogel synthesized on the basis of TMOS (tetra methyl ortho silicate) precursor and in the presence of two co-precursors, tri fluoro propyl-tri methoxy silane and di-ethyl tri-methyl silyl phosphite. As the obtained results show, this aerogel is highly capable to uptake Mo in an optimum concentration of metal solution of about 10 ppm, the optimum pH about 4, contact time about 5 hours and the adsorbent dose about 3gr for 50ml of metal solution. The kinetics approaches show that the rate of this adsorption follows a first order reaction and the rate constant (Kad) is equal to 0.1248(h^-1). The thermodynamic approaches have also been studied, and thereby the feasibility and the spontaneous nature of  Mo ions adsorption on aerogel have been demonstrated. A comparison between obtained results from silica aerogel and the activated carbon shows the more capability of the synthesized silica aerogel.

Highlights

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Keywords

• Adsorption
• Molybdenum
• Silica Aerogel
• Activated Carbon
• Hydrophobic
• Precursor