The use of insoluble mater of Moroccan oil shale for removal of dyes from aqueous solution

ISSN: 2410-9649 Chham et al / Chemistry International 4(1) (2018) 67-77 iscientic.org. 68 www.bosaljournals/chemint/ editorci@bosaljournals.com same time, there are concerns, and there is the need to find cheap and efficient methods for the industrial waste water prior to disposal in to natural waters (Gürses et al., 2006; Wang et al. 2005). The removal of dyes from wastewater has been extensively studied for decades, and many technologies have been developed, including oxidative degradation (Jadhav et al., 2011), biochemical degradation (Gardiner et al., 1978; Li et al., 2015), photo-degradation (Kalyani et al., 2009; Thiam et al., 2016), electrocoagulation (Janoš et al., 2003), electrochemical degradation (Espantaleón et al., 2003), and adsorption (Han et al., 2008; Mittal et al., 2010). The advantages and disadvantages of every removal technique have been extensively reviewed (Chiou et al., 2006; Hameed et al., 2009). Among these methods, adsorption has been found to be one of the most well-known and economic techniques for dye removal due to its easy operation, high efficiency, low cost, and recyclability (Low et al., 1990). Most recently, much attention has been paid to the development of crude biomass materials, such as peanut husk (Guechi et al., 2016), coconut husk (Vadivelan et al., 2005), potato peel (Amin et al., 2009), rice husk (Salleh et al., 2011), and pomegranate peel (Guechi et al., 2016), for the removal and separation of dyes from the wastewater. Their removal of dyes in an economic way remains an important issue for researchers and environmentalists. The adsorption is an excellently tentative election especially using in expensive and high adsorption capacity adsorbent without requiring any additional pretreatment step be for application. Adsorption is superior to other waste water treatment techniques in terms of its initial cost, flexibility and simplicity of design, ease of operation and insensitivity to toxic pollutants (Gupta et al., 2007; Tan et al., 2008; Sachdeva et al., 2009; Al-Ghouti et al., 2009; Akgul et al., 2011; Alexandro et al., 2011). Mining and processing of the oil shale will significantly disturb the environment, as are sult of pollution by dust particles and ash derived from the oil shale (Toomik et al., 1998; Jaber et al., 1999). Valorization of these valuable by product will reduce the environmental impact and will make oil shale development economically feasible for energy production in the future (Hamadi et al., 2012). In this context, the present study is part of a series of studies that we conducted on the possibility of producing adsorbent materials from Moroccan oil shale (Ichcho et al., 2003; Ichcho et al., 2005; Ichcho et al., 2006). The choice of this material for this application, elaboration of adsorbents material, was ducted by two factors; the reserve estimated at 80 billion tons in Tarfaya and 20 billion tons in Timahdit and its composition rich in organic matters, constituted a source of carbon, chemically linked to the mineral matrix (carbonates, silicates and clays). The previous were focalized great attention to the activation of a precursor obtained after decarbonization of the raw rock of oil shale. The methods used are based on thermal activation (Ichcho et al., 2003; Ichcho et al., 2005) without chemical activation by different activates agents (phosphoric acid, sulfuric acid, sodium hydroxide, potassium hydroxide, zinc chloride,...) (Ichcho et al., 2005; Ichcho et al., 2006). The adsorbent obtained by these methods have a good structural properties and showed a good affinity against the organic and inorganic pollutants stable (Ichcho et al., 2003; Ichcho et al., 2005 ; Ichcho et al., 2006; Khouya et al., 2006). On the other hand, El Harti et al. optimize the procedure parameters of elaboration the adsorbents from two precursors; the raw rock Y and the decarbonized raw rock YH. The parameters examined in this study are: the activation temperature, the residence time in the furnace and the atmosphere gas. The textural and structural characteristics of the prepared adsorbents and their removal capacity of the methylene blue molecule revealed that the best adsorbents are obtained upon activation of the two precursors at 300 °C in air but with durations of different activation, 2h for Y and 2.30 for YH (El Harti et al., 2012). Zhao et al. (Zhao et al., 2014) removed MB from solution by using oil shale ash, the experimental results showed that both the Langmuir and Freundlich models fitted the MB adsorption data well with an adsorption capacity as high as 250 mg/g. Removal of MB by OSA was relatively fast and equilibrium could be achieved in 2 h. Recently Gouza et al. (Gouza et al., 2017) study the effect of heat treatment on the surface properties of selected bituminous shale for cationic dye sorption, the result show that the active sites from shale play an important role for MB removal. As a result, this natural, widely available and low-cost resource can be a good adsorbent used for many removal applications of specific pollutants.Therefore, two principal objectives were fixed for the present research: (a) Studied of experimental conditions for the preparation of the adsorbents prepared from the decarbonized oil shale (denoted as YH in the text), such as time and temperature of thermal treatment, mass ratio of adsorbent. (b) Tested the ability of the elaborated adsorbents to retain the methylene blue (MB) which was a dye, commonly employed as indicator to evaluate adsorbents and compared their adsorption capacities with some others activated carbons, and determination of best conditions of adsorption (contact time, pH of MB and heating temperature of solution). MATERIAL AND METHODS