Hybrid approaches based on hydrodynamic cavitation, peroxymonosulfate and UVC irradiation for treatment of organic pollutants: fractal like kinetics, modeling and process optimization.

Hydrodynamic cavitation (HC) was emerged as one of the most potential technologies for industrial-scale wastewater or water treatment. In this work, a combined system of HC, peroxymonosulfate (PMS) and UVC irradiation (HC - PMS - UVC) was constructed for effective degradation of carbamazepine. The effect of several experimental parameters and conditions on the carbamazepine degradation was considered. The results show that the degradation and mineralization rates increases with an increase in the inlet pressure from 1.3 to 4.3 bars. The rates of carbamazepine degradation with the combined processes of HC - PMS - UVC, HC - PMS, HC - UVC, and UVC - PMS were 73%, 67%, 40% and 31%, respectively. Under the optimal conditions of reactor, the carbamazepine degradation and mineralization rates were 73% with 59%, respectively. The kinetics of carbamazepine degradation was studied applying a fractal-like approach. So, a new model was proposed by combining first order kinetics model and fractal-like concept. The obtained results show that the proposed fractal-like model gives a better performance compared with traditional first order kinetics model. It has been demonstrated that the HC - PMS - UVC process is a potential treatment method to destroy pharmaceutical pollutants from water and wastewater sources.

Alginate-Based Hydrogel Beads as a Biocompatible and Efficient Adsorbent for Dye Removal from Aqueous Solutions.

In this study, sodium alginate was employed as a starting material for preparing two kinds of biocompatible adsorbents, including calcium alginate hydrogel beads and magnetic hydrogel beads. Fourier transform infrared spectroscopy, X-ray diffraction pattern, and scanning electron microscopy/energy-dispersive X-ray techniques were used to characterize the prepared adsorbents. The performance of the prepared adsorbents for the removal of methyl violet from aqueous solution was studied in detail. Both kinetics and equilibrium aspects of methyl violet adsorption were investigated, and the obtained equilibrium and kinetics data were described with various adsorption models. The effects of initial dye concentration, adsorbent dosage, and temperature on adsorption performance were investigated. Thermodynamic parameters of adsorption were obtained as well.