Sepiolite has been treated with ethanol under isothermal conditions and characterized by XRD, SEM, FT-IR, and BET measurements. The materials showed a typical lamellar structure and fibrous morphology. After treatment of sepiolite, the surface area of the solid is significantly improved while the material structure still remains. | VNU Journal of Science: Natural Sciences and Technology, Vol. 32, No. 4 (2016) 64-71 Characteristics and Rhodamine B Adsorption Ability of Modified Sepiolites Nguyen Tien Thao1,*, Ta Thi Huyen1, Doan Thi Huong Ly1, Han Thi Phuong Nga1,2, 1 2 Faculty of Chemistry, VNU University of Science Faculty of Environment, Vietnam National University of Agriculture Received 6 July 2016 Revised 05 August 2016; Accepted 01 September 2016 Abstract: Sepiolite has been treated with ethanol under isothermal conditions and characterized by XRD, SEM, FT-IR, and BET measurements. The materials showed a typical lamellar structure and fibrous morphology. After treatment of sepiolite, the surface area of the solid is significantly improved while the material structure still remains. Both fresh and treated sepiolites were used as adsorbents for the adsorption of rhodamine B in water. In isothermal conditions, both samples exhibit a good ability to adsorb rhodamine B in water. Experimental results indicate that the adsorption of rhodamine B for sepiolite was fitted to the Langmuir and Freundlich adsorption models. The treated sepiolite showed a higher adsorption capacity than does the fresh sample. Keywords: Sepiolite, Adsorbent, rhodamine B, Langmuir, Freundlich. 1. Introduction* of synthetic organic compounds consisting of aromatic structures that are stable in water [1, 4, 5]. These dyes may be treated by the photodegradation or advanced oxidation process [2, 4]. Photosynthesis was known as a promising way to eliminate these toxic compounds but has a limitation due to inhibition of sunlight penetration; while the advanced oxidation process usually requires to use expensive oxidants such as H2O2 [2, 3]. Recently, scientists are therefore focused on the removal of dye from effluent using the adsorption methods, which do not generate secondary harmful substances resulting from the incomplete oxidation of dyes [5-10]. Activated carbon, clays, mesoporous silicas are A vast amount of .
