Concepción-Rosabal, B., Bogdanchikova, N., De la Rosa, I., Olguin, M.T., Alcantara, D. and Rodriguez-Fuentes, G. (2006) Properties and Utilization of Natural Zeolites. 7th International Conference on the Occurrence, New Mexico, 16-21 July 2006, 88-89.

has been cited by the following article:

• TITLE: Removal of Ag(I) from Aqueous Solution by Japanese Natural Clinoptilolite

  AUTHORS: Takaaki Wajima

  KEYWORDS: Clinoptilolite, Ag(I) Removal, Adsorption, Natural Zeolite

  JOURNAL NAME: Advances in Chemical Engineering and Science, Vol.6 No.4, October 12, 2016

  ABSTRACT: The present study examined the adsorption of silver ion in aqueous solution onto natural clinoptilolite zeolite from Futatsui Mine, Akita Prefecture, Japan. The effects of various parameters, i.e., solution pH, adsorbent dosage, adsorption time, silver ion solution concentration, and temperature, on silver ion adsorption process onto clinoptilolite were examined. Additionally, the thermodynamics of the silver ion adsorption process was investigated. The optimum pH for silver adsorption was determined to be around 4.0. The adsorption process could be well described by the Langmuir isotherm model. The calculated maximum adsorption capacity was 0.64 mmol/g. Adsorption kinetics studies were also conducted. The results showed that the adsorption process preferentially followed the pseudo-second-order kinetics model over the pseudo-first-order model. Furthermore, with decreasing aqueous solution temperatures, the adsorption kinetics became slower and the amount of silver ion adsorbed increased. The thermodynamic values, ΔG0, ΔH0, and ΔS0, indicated that adsorption was an exo-thermic and spontaneous process.