Preparation and characterization of nano hydroxyapatite / Clinoptilolite and the removal of environmental pollutants Fluorine S. Jalalvandi Fard,a M. Zendehdel,a* , M.Haddadia a Department of Chemistry, Faculty of Science, Arak University, Arak38156-8- 8349; Iran *Corresponding author: m-zendehdel@araku.ac.ir 1. Introduction The increasing population and urbanization of society caused to increase production and distribution of toxic chemicals, into the environment [1]. One of the known disruptors is Fluoride. Since most types of pollution, water pollution is caused by fluorine, the concentration Fluoride is one of the most important factors in choosing safe drinking water. In the 1930s in America, it was found that the cause of death and paralysis in humans Is fluorine. According to one of organizations of Health America in this areas, bone cancer that is caused by fluoride is three times [2]. In this study NaP:HAp nanocomposite was used as an effective adsorbent for removal of fluoride from aqueous solution and Also in this study, Box-Behnken design with three-level and four-factor has been employed determination of effective process parameters . Fluoride uptake quantitatively evaluated using the Langmuir and Freundlich models [3]. 2. Experimental Part or Theoretical Details The starting materials used in this study included, calcium nitrate (CNT), potassium dihydrogen phosphate (KPP), ammonia and deionized water. All chemical materials supplied by Merck and aqueous solutions were made dissolving them in deionized water. XRD, FT-IR, TGA,EDX and SEM were used to characterization of obtained product. At first NaP zeolite and hydroxyapatite was prepared separately. Clinoptilolite Natural Zeolite has been developed of Semnan mine. and then nanocomposite of NaP:HAp synthesized with hydrothermal method at 40˚C for 24h. Batch experiments were carried out using synthetic NaP:HAp. The effect of solution PH (4-11), temperature (25-55 ̊C), initial adsorbent dose (1-3 g) and i