کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5139078 | 1494861 | 2017 | 37 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Sorption of Cr(III) and Cr(VI) to K2Mn4O9 nanomaterial a study of the effect of pH, time, temperature and interferences
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
![عکس صفحه اول مقاله: Sorption of Cr(III) and Cr(VI) to K2Mn4O9 nanomaterial a study of the effect of pH, time, temperature and interferences Sorption of Cr(III) and Cr(VI) to K2Mn4O9 nanomaterial a study of the effect of pH, time, temperature and interferences](/preview/png/5139078.png)
چکیده انگلیسی
A Rancieite type material (K2Mn4O9) nanomaterial was synthesized and tested for the removal of chromium (III) and chromium (VI) from aqueous solutions. The synthesized nanomaterial was characterized using powder XRD and SEM. XRD showed weak diffraction peaks at only at the angles associated with K2Mn4O9. The SEM corroborated that the nanoparticles were present; however, the nanoparticles were clustered into larger aggregates. Batch studies were performed to determine the optimum pH, capacity, time dependency, interferences, and the thermodynamics of the binding. The optimum pH for the binding of Cr(III) and Cr(VI) were determined to be pH 5 and pH 2, respectively. Isotherm studies were performed at temperatures of 4 °C, 25 °C, and 45 °C for Cr(III) and Cr(VI) and showed binding capacities of 21.7 mg/g, 36.5 mg/g, 41.8 mg/g for Cr(III). The Cr(VI) binding capacities were 4.22 mg/g, 4.08 mg/g, and 3.25 mg/g at the respective temperatures. The thermodynamic studies showed that the binding processes for the reactions were spontaneous and endothermic, with a â H was 17.54 kJ/mol for Cr(III) and 6.05 kJ/mol for Cr(VI). The â G of sorption for Cr(III) were determined to be â 3.88 kJ/mol, â 5.83 kJ/mol and â 7.03 kJ/mol at the aforementioned temperatures. The ÎG values for the Cr(VI) sorption were determined to be â 4.89 kJ/mol, â 5.64 kJ/mol, and â 6.05 kJ/mol. In addition, the ÎS values for Cr(III) and Cr(VI) were determined to be 77.92 J/mol and 39.49 J/mol, respectively. The thermodynamics indicate that the binding of Cr(III) and Cr(VI) is spontaneous and endothermic.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Microchemical Journal - Volume 133, July 2017, Pages 614-621
Journal: Microchemical Journal - Volume 133, July 2017, Pages 614-621
نویسندگان
J.P. Valle, B. Gonzalez, J. Schulz, D. Salinas, U. Romero, D.F. Gonzalez, C. Valdes, J.M. Cantu, T.M. Eubanks, J.G. Parsons,