عنوان مقاله [English]
نویسندگان [English]چکیده [English]
Hexavalent chromium is a pollutant found in surface and underground waters that causes serious environmental hazards. Chromium enters water as a result of industrial activities such as electroplating, dyeing, leather tanning, and metal manufacturing. The objective of the present laboratory-experimental study was to remove chromate from industrial effluents using silicon nanoparticles. The experiments were performed with both simulated synthetic wastewater and true wastewater. Various parameters such as pH, contact time, and different concentrations of Cr(VI) and SiO2 were examined. The data obtained were analyzed using the Excel and SPSS Ver. 16. It was found that Cr(VI) removal increased with decreasing pH and increasing contact time. The highest Cr(VI) removal was achieved at pH=3 and a contact time of 120 minutes. It was also observed that removal observed to obey the Langmuir isotherm and pseudo second-order kinetic models, respectively. The findings indicate that silicon nanoparticles are capable of removeing Cr(VI) from industrial effluents. Given the Cr(VI) removal efficiency of 93.6% achieved under optimum conditions and the removal efficiency of 88.6% achieved in real samples, the method may be recommended as a highly efficient one for removing Cr(VI) from industrial wastewaters.
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