کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
580640 1453154 2010 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Brazil nut shells as a new biosorbent to remove methylene blue and indigo carmine from aqueous solutions
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی بهداشت و امنیت شیمی
پیش نمایش صفحه اول مقاله
Brazil nut shells as a new biosorbent to remove methylene blue and indigo carmine from aqueous solutions
چکیده انگلیسی
The adsorption of methylene blue and indigo carmine, respectively a basic and an acid dye, was studied on raw Brazil nut shells. The dye removal from solution by BNS was governed by: (i) polarization effects between the colored ions and the surface sites, leading to physisorbed species due to weak electrostatic forces and (ii) diffusion limitations affecting the kinetic parameters. Thermodynamic studies showed that the adsorption of methylene blue and of indigo carmine was spontaneous and exothermic occurring with entropy decrease. H0 values confirmed the physical nature of the adsorption processes. The adsorption followed the Langmuir model and pseudo-second order kinetics over the entire range of tested concentrations but the process was controlled by intraparticle diffusion. The maximal uptakes were 7.81 mg g−1, for methylene blue, and 1.09 mg g−1 for indigo carmine, at room temperature. These results indicate that Brazil nut shells may be useful as adsorbent either for basic or acid dyes.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Hazardous Materials - Volume 174, Issues 1–3, 15 February 2010, Pages 84-92
نویسندگان
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