Arsenic is one of the most toxic compounds you can find. Despite their toxicity, inorganic arsenic compounds are naturally present in small amounts on earth. Humans can be exposed to arsenic through food, water and air. Exposure can also occur through skin contact with contaminated soil or water.
Arsenic, classified as a group 1 human carcinogen by the World Health Organization (WHO) (2011), has been reported at significant concentrations in groundwater due to its toxicity and its presence, l World Health Organization (WHO) and the Vietnamese Ministry of Health has set the maximum contaminant for arsenic at 10 µg / L for drinking water (Choong et al. 2007; Sharma and Sohn 2009).
Arsenic can be removed from the water in different ways. Examples of water purification techniques that can be applied are oxidation (van Genuchten et al. 2012), coagulation (Pramanik et al. 2016), chemical precipitation (Harper and Kingham 1992), membrane filtration (Fogarassy et al. 2009), ion exchange (Ning 2002) etc. among these adsorption there are several advantages compared to other methods, due to the low investment cost, ease of use and efficiency of removal of pollutants .
Many absorbents have been reported for the elimination of arsenic (V), such as chitosan (Chen and Chung 2006) Nano-crystalline kaolinie (Amer and Awwad 2018), Treated zeolite (Ahmad and Awwad 2010), activated carbon (Huang and Fu 1984), Natural siderite and hematite (Guo et al. 2007), alumina (Lin and Wu 2001), Fe7S8 nanoparticles (Cantu et al. 2016), and Magnetite (Yean et al. 2005). The use of products of natural origin, such as apatite, because they are more abundant and effective as adsorbents
Natural Moroccan phosphates are essentially sedimentary in nature. Phosphate rocks are mainly made up of fluoroapatite (Ca5 (PO4)3F) which is weakly crystallized and widely used thanks to its adsorption and ion exchange properties (Cao et al. 2009). The presence of minerals such as calcite and dolomite in the sedimentary apatite is very beneficial for the retention of phosphorus thanks to the good dissolution of these carbonate minerals. This results in an increase in the pH of the reaction medium and in the concentration of Ca2+ ions in solution, which promotes the precipitation of calcium phosphate (Mobasherpour et al. 2011). Apatites have been widely used thanks to their great capacity to immobilize different heavy metals such as Cd2+, Pb2+, Zn2+, Cu2+, Ni2+, Cr6+ (Aklil et al. 2004; Yaacoubi et al. 2014).
The proposed exchange mechanisms are different depending on the element considered and the natural conditions. There are ionic exchanges (exchanges on the cationic sites of Ca2+) associated with a diffusion in the apatitic structure. During this process, the ionic radius and the electronegativity of the metal ion seem to be the main parameters of this mechanism (Cao et al. 2004).
In this work, two objectives were taken into account: The treatment of Moroccan natural phosphate by a heat treatment The second objective is the elimination of As(V) dissolved in synthetic solutions by adsorption on calcined phosphate. In this study, we studied the structure and morphology of FApC using X-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Information on the structure was also obtained by spectroscopy measurements. Fourier transform infrared spectroscopy (FTIR) measurements,The adsorption capacity of As (V) has been demonstrated using the ICP technique.