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In the preparation of nanocomposites, there is competition between the dispersion of nanoparticles and the formation of agglomerates. In this study, radical copolymerization of ethyl acrylate and methyl methacrylate initiated by 2,2‐azobis (isobutyro) nitrile (AIBN) was performed, in the presence of titanium oxide (TiO2) nanoparticles modified in a new approach; a good dispersion of the nanoparticles in the unsaturated polyester (UP) matrix was obtained. The TiO2 nanoparticles were exposed to 3‐(methacryloxy) propyl trimethoxy silane as the coupling agent. The presence of coupling agent‐grafted TiO2 nanoparticles in the copolymerization process resulted in the formation of a polymeric layer on the surface of the TiO2 nanoparticles (doubly modified‐TiO2). The grafting of coupling agent molecules and consequently copolymer macromolecular chains onto the surface of TiO2 nanoparticles was investigated using Fourier transform infrared (FTIR) analysis. It found that the formation of an acrylate layer on the sur...

7 páginas, 6 figuras, 1 tabla., This laboratory research was carried out to evaluate the performance of a multistage anaerobic biofilm reactor, with six compartments and a working volume of 70 L, for the treatment of a strong synthetic nitrogenous and high-strength wastewater at an operational temperature of 26 ± 0.5 °C. Initially, the performance of the reactor was studied when subjected to an increase in the hydraulic retention time (HRT) at a constant influent COD concentration of 10,000 mg/L. Five different HRTs were studied: 0.25, 0.67, 1, 3 and 5 days, which were equivalent to 6, 16, 24, 72 and 120 h, respectively. By increasing the HRTs from 6 h to 1 day, COD and BOD removal efficiencies were increased from 63% to 84% and from 66% to 87%, respectively. Moreover, at an HRT of 3 days, COD and BOD removal efficiencies were equal, reaching 93%. In the second phase of the research, the effect of adding nitrate with a concentration of 3000 mg/L at an influent organic loading rate of 10 g COD/L d was researched on the reactor performance and the amount of biogas produced. Denitrification took place almost solely in the first three compartments of the reactor, with efficiencies of 85%, 95% and 98%, respectively. The nitrite produced was only detected in the first and second compartments at concentrations of 138 and 24 mg/L, respectively. In addition, no accumulation of nitrite was detected in the reactor. Furthermore, the denitrification caused an increase in the total volume of produced biogas from 102 to 178 L/d., The authors gratefully acknowledge the financial support of the Water Research Center of Greentech (Co., Ltd.), Shiraz and the R&D center of Anshan Corporation.