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Emerging and hazardous environmental pollutants like phthalic acid esters (PAEs) are one of the recent concerns worldwide. PAEs are considered to have diverse endocrine disrupting effects on human health. Industrial wastewater has been reported as an important environment with high concentrations of PAEs. In the present study, four short-chain PAEs including diallyl phthalate (DAP), diethyl phthalate (DEP), dimethyl phthalate (DMP), and phthalic acid (PA) were selected as a substrate for anaerobic fixed film fixed bed reactor (AnFFFBR). The process performances of AnFFFBR, and also its kinetic behavior, were evaluated to find the best eco-friendly phthalate from the biodegradability point of view. According to the results and kinetic coefficients, removing and mineralizing of DMP occurred at a higher rate than other phthalates. In optimum conditions 92.5, 84.41, and 80.39% of DMP, COD, and TOC were removed. DAP was found as the most bio-refractory phthalate. The second-order (Grau) model was selected as the best model for describing phthalates removal.

The present work aimed to study the removal efficiency of Reactive Blue 222 (RB222) from aqueous solutions by applying a combined process with magnetic sodium alginate beads/H2O2. The effect of various operating parameters including sodium alginate dosage, H2O2 concentration, pH, and dye concentration on the efficiency of the process was investigated. The Freundlich and Langmuir isotherms were used to explain the adsorption process. Adsorption kinetics of RB222 with magnetic sodium alginate beads were also investigated using the pseudo‐first‐, second‐order, and intra‐particle diffusion kinetic models. Optimum conditions for dye removal were determined at [dye concentration] = 50 mg/L, [H2O2] = 250 mg/L, and [pH] = 3 with a reaction time of 180 min. Dye removal percentages obtained in this research were 54.51% and 90.39% using magnetic sodium alginate and magnetic sodium alginate/H2O2 processes, respectively. SEM and XRD were used for the characterization of the obtained magnetic sodium alginate beads. It was revealed that the adsorption of the dye in sodium alginate beads was more consistent with the Freundlich model (R2 = 0.9934) compared to that of the Langmuir model (R2 = 0.7457). Also, the results demonstrated that the adsorption of RB222 in magnetic alginate beads was consistent with the pseudo‐second‐order kinetic models (R2 = 0.9854). © 2018 American Institute of Chemical Engineers Environ Prog, 38: S205–S213, 2019

a b s t r a c tBisphenol A (BPA) is one of the endocrine disrupting compounds that has significant estrogenic effects and if it is not treated, it will enter into water resources and will cause irreparable environmental problems. Thus, this study aims at determining the efficiency of heterogeneous Fenton-like process using modified magnetic nanoparticles with sodium alginate in removing BPA from aquatic environments. In this experimental research, the effects of environmental factors including pH (3-9), contact time (10-180 min), initial concentration of catalyst (0.5-20 g/L), initial concentration of hydrogen peroxide (50-300 mg/L) and the initial concentration of BPA (10-60 mg/L) were studied in removing efficiency of BPA using processes of heterogeneous Fenton-like, alginate sodium and hydrogen peroxide. Results of present study showed that during heterogeneous Fenton-like process, the highest removal efficiency (BPA) is achieved (95%) at pH 5, catalyst concentration 5 g/L, initial concentration of hydrogen peroxide 100 ppm and BPA concentration 20 ppm in 120 min in a way that the processes of sodium alginate and hydrogen peroxide had smaller removal efficiency. Also, studies of kinetic reaction revealed that removal of BPA in heterogeneous Fenton-like process followed a second-order kinetic model (R 2 = 0.98). Results demonstrated that heterogeneous Fenton-like process is able to remove BPA effectively from aquatic environments using modified magnetic nanoparticles with sodium alginate as a catalyst under optimal conditions and this process could be used to remove other similar compounds.