پديدآورندگان :
Mohammadi Sayed Zia szmohammadi@yahoo.com Department of Chemistry, Payame Noor University, Tehran, Iran , Karimi Mohammad Ali - Department of Chemistry, Payame Noor University, Tehran, Iran , Mofidi Nasab Nastaran - Department of Chemistry, Payame Noor University, Tehran, Iran
چكيده فارسي :
Dyes are used in many industries such as food, paper, carpets, rubbers, plastics, cosmetics, and textiles in order to color their products. The discharge of colored wastewater from these industries into natural streams has caused many significant problems such as increasing the toxicity and chemical oxygen demand (COD) of the effluent, and also reducing light penetration, which has a derogatory effect on photosynthetic phenomena. From the aesthetic point of view, the presence of dyes, in particular carcinogenic compounds, in surface and underground waters is not safe, pleasant, or welcomed. Recently, governments have been under severe pressure by their constituents to stop this type of effluent from entering public watercourses, unless it is treated properly [1]. The most commonly used methods for color removal are biological and chemical precipitation. However, these processes are effective and economic only in cases where solute concentrations are relatively high [2]. There are advantages and disadvantages of various methods of dye removal from wastewaters [3]. Many physicochemical methods have been tested, but only that of adsorption is considered to be superior to other techniques. This is attributed to its low cost, easy availability, simplicity of design, high efficiency, ease of operation, biodegradability, and ability to treat dyes in more concentrated forms [4]. In recently years, the magnetic activated carbon have been widely used as an adsorbent for the removal of toxic metals and organic pollutants from aqueous solutions due to their large specific surface area, chemical and mechanical stability, layered structure and high capacity.In the present work, the removal of methylene blue from aqueous system based on magnetic activated carbon was evaluated. The physicochemical and morphological characterization of the synthesized magnetic activated carbon was studied by using XRD and FT-IR techniques. Then, the magnetic activated carbon was used for removal of methylene blue and the equilibrium data was evaluated by adsorption isotherm model and thermodynamic equations. The maximum adsorption capacity of methylene blue on the magnetic activated carbons was 51.8 mg g−1.
