TY - JOUR ID - 1531 TI - Ultrasound-assisted adsorption of Cr (VI) ions from aqueous solution: Experimental study and CFD simulation JO - Journal of Applied Research in Water and Wastewater JA - ARWW LA - en SN - AU - Niknezhad, Nazanin AU - Azimi, Neda AU - Ahmadi, Shahin AD - Department of Chemical Engineering, Kermanshah Branch, Islamic Azad University, Kermanshah, Iran AD - Department of Chemical Engineering, Kermanshah Branch, Islamic Azad University, Kermanshah, Iran. AD - Department of Chemistry, Kermanshah Branch, Islamic Azad University, Kermanshah, Iran Y1 - 2021 PY - 2021 VL - 8 IS - 1 SP - 41 EP - 49 KW - Adsorption KW - Ultrasound KW - CFD modeling KW - Bentonite KW - Nanoparticles KW - Activated carbon KW - Sono-container DO - 10.22126/arww.2020.5153.1165 N2 - The purpose of this study was numerical and experimental investigations on the influence of ultrasound on Cr (VI) removal from aqueous solution by adsorption onto activated carbon nanoparticles. The effect of key factors on Cr (VI) elimination like media pH, absorbent mass, initial concentration of Cr (VI) and the location of ultrasound transducers were considered. To perform CFD modeling of ultrasound propagation, the vibrations of 1.7 MHz piezoelectric transducers (PZTs) were defined based on the dynamic mesh model. The experimental results indicated that by pH raising from 2 to 8, Cr (VI) removal efficiency had a decreasing trend and at pH=8, it had the lowest value. The adsorption rate increased by augmentation in the adsorbent mass (AM) due to the enhancing its specific surface area. In comparison with using a shaker, ultrasound showed lower needed contact time for Cr (VI) elimination at identical conditions. In addition, CFD results depicted that the acoustic streams were induced in the direction of ultrasound propagation, which is caused to reach the better mixing and Cr (VI) removal efficiency. Finally, the experimental data were adopted with the Langmuir and Freundlich isotherms. The comparison of these models showed that both models were well suited to experimental findings and the data compatibility with Langmuir model was greater. UR - https://arww.razi.ac.ir/article_1531.html L1 - https://arww.razi.ac.ir/article_1531_a0a17ebad6d1049f9faf8a751291b889.pdf ER -