Iranian Research Organization for Science and Technology Advances in Environmental Technology 2476-6674 2 2 2016 04 01 Synthesis of nanocomposite based on Semnan natural zeolite for photocatalytic degradation of tetracycline under visible light 63 70 399 10.22104/aet.2016.399 EN Farzaneh Saadati Faculty of Nanotechnology, Semnan University, Semnan, 35131-19111, Iran Narjes Keramati Faculty of nanotechnology, Semnan University, Semnan, 35131-19111, Iran Mohsen Mehdipour Ghazi Faculty of Chemical, Petroleum and Gas Engineering, Semnan University, Semnan, 35131-19111, Iran Journal Article 2016 06 13 This study investigated the photocatalytic behaviors for the nanocomposite of TiO₂ P25 and Semnan natural zeolite in the decomposition of tetracycline under visible light in an aqueous solution. The structural features of the composite were investigated by a series of complementary techniques that included X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), surface area (BET) measurement, and ultraviolet-visible diffuse reflectance spectroscopy (DRS). The surface area measurement disclosed an enhancement of surface area by ~2 times for the synthesized TiO₂/Semnan natural zeolite than that of commercial TiO₂ P25. The as-prepared photocatalyst (TiO₂/Semnan natural zeolite) showed pH dependence and more than 87% of the tetracycline could be degraded from the solution under visible irradiation within 90 min at a pH of 6. This excellent catalytic ability was mainly attributed to the hybrid effect of the photocatalyst and adsorbent. The results provided new insight into the performance of active photocatalysts on the treatment of pharmaceutical wastewater. In addition, the immobilization of TiO₂ onto Semnan natural zeolite permitted easier separation of the adsorbent from the treated water. https://aet.irost.ir/article_399_3d25ef6bb2a30aa32c8b08f12f435d75.pdf

Iranian Research Organization for Science and Technology Advances in Environmental Technology 2476-6674 2 2 2016 04 01 Comparison and analysis of two natural adsorbents of Sorghum and Ziziphus nummularia pyrene for removal of Erythrosine dye from aquatic environments 71 76 381 10.22104/aet.2016.381 EN Nayereh Yahyaei Department of Chemical Engineering, Shahrood Branch, Islamic Azad University, Shahrood, Iran Javad Mousavi Department of Chemical Engineering, Gas and Petroleum, Semnan University, Semnan, Iran Mehdi Parvini Department of Chemical Engineering, Gas and Petroleum, Semnan University, Semnan, Iran Pedram Mohebi Department of Chemical Engineering, Shahrood Branch, Islamic Azad University, Shahrood, Iran Journal Article 2015 05 13 One pollutant which seriously threatens water resources is dye. Therefore, finding a suitable method to separate the dye in water resources is very important. An adsorption process that uses low cost adsorbents is considered as an efficient strategy for this purpose. In this study, Erythrosine dye removal from an aquatic environment using natural absorbents, namely Sorghum and Ziziphus nummularia pyrene, was reviewed. The effects of different parameters such as pH, contact time, initial density, and the adsorbent amount in the batch system were investigated. The results indicated that increased temperature has no significant effect on the removal of Erythrosine dye, and the highest adsorption was achieved in the first 30 min of adsorbent- dye contact time. Also, most of the adsorption occurred at pH values of 4-8. Moreover, the highest amount of dye removal was observed in a concentration of 20 mg/L for the Ziziphus nummularia pyrene adsorbent and 5 mg/L of the Sorghum adsorbent. Also, the Langmuir and Freundlich equations were used to analyze the adsorption process, where both the Sorghum and Ziziphus nummularia pyrene adsorbents showed a better agreement with the Langmuir isotherm. https://aet.irost.ir/article_381_c5fdde67d1b7067900ed1ac6ed603104.pdf

Iranian Research Organization for Science and Technology Advances in Environmental Technology 2476-6674 2 2 2016 04 01 Photocatalytic degradation of textile dye direct orange 26 by using CoFe2O4/Ag2O 77 84 400 10.22104/aet.2016.400 EN Mohsen Mehdipour Ghazi Faculty of Chemical, Petroleum, and Gas Engineering, Semnan University, Semnan, 35131-19111, Iran Fatemeh Azhdari Faculty of Chemical, Petroleum and Gas Engineering, Semnan University, Semnan, 35131-19111, Iran. Journal Article 2016 05 04 The magnetic and recyclable nanoparticles of CoFe₂O₄ were synthesized by a reverse co-precipitation process. Sonication was used to couple the CoFe₂O₄ surface with Ag₂O. The characteristics and optical properties of the catalyst were studied by powder X-ray diffraction, UV–visible reflectance spectroscopy and scanning electron microscopy analyses. Pure CoFe₂O₄ and CoFe₂O₄/Ag₂O were utilized to determine the visible light photocatalytic degradation of Direct Orange 26. The effects of pH, the initial concentration of catalyst and initial dye concentration on the photocatalytic process were investigated. It was found that the presence of Ag₂O remarkably improved the photocatalytic adsorption capacity and degradation efficiency of CoFe₂O_4­/Ag₂O when compared with the pure CoFe₂O₄. Moreover, due to the magnetic behavior of CoFe₂O₄, these coupled nanoparticles can be easily separated from the aqueous solution by applying an external magnetic field. The prepared Ag₂O-modified CoFe₂O₄ exhibited much higher (about 40%) photocatalytic activity than the unmodified one. The results showed that the loading of the Ag₂O significantly improved the photocatalytic performance of the CoFe₂O₄ in which the Ag₂O acted as a charge carrier to capture the delocalized electrons. https://aet.irost.ir/article_400_4b5b89196b581f9fccc04fa8ee62f50c.pdf

Iranian Research Organization for Science and Technology Advances in Environmental Technology 2476-6674 2 2 2016 04 01 Removal of copper (II) from aqueous solutions by adsorption onto granular activated carbon in the presence of competitor ions 85 94 392 10.22104/aet.2016.392 EN Saeed Almohammadi Department of chemical engineering, Mahshahr branch, Islamic azad university, Mahshahr, Iran Masoomeh Mirzaei Department of chemical engineering, Mahshahr branch, Islamic azad university, Mahshahr, Iran Journal Article 2016 07 01 In this work, the removal of copper from an aqueous solution by granular activated carbon (GAC) in the presence of competitor ions was studied. A batch adsorption was carried out and different parameters such as pH, contact time, initial copper concentration and competitor ions concentration were changed to determine the optimum conditions for adsorption. The optimum pH required for maximum adsorption was found to be 4.5 for copper. Equilibrium was evaluated at 144 h at room temperature. The removal efficiency of Cu(II) was 71.12% at this time. The kinetics of copper adsorption on activated carbon followed the pseudo second-order model. The experimental equilibrium sorption data were tested using the Langmuir, Freundlich, Temkin and Dubinin–Radushkevich (D-R) equations and the Langmuir model was found to be well fitted for copper adsorption onto GAC. The maximum adsorption capacity of the adsorbent for Cu(II) was calculated from the Langmuir isotherm and found to be 7.03 mg/g. Subsequently, the removal of copper by granular activated carbon in the presence of Ag¹⁺ and Mn²⁺ as competitor ions was investigated. The removal efficiency of Cu(II) ions without the presence of the competitor ions was 46% at 6 h, while the removal efficiency of Cu(II) ions in the presence of competitor ions, Ag¹⁺ and Mn²⁺ , was 34.76% and 31.73%, respectively. https://aet.irost.ir/article_392_f5dc1609c14b136c11dee78dae622766.pdf

Iranian Research Organization for Science and Technology Advances in Environmental Technology 2476-6674 2 2 2016 04 01 The effects of operating factors on the removal of total ammonia nitrogen and florfenicol antibiotic from synthetic trout fish farm wastewater through nanofiltration 95 103 389 10.22104/aet.2016.389 EN Ali Reza Solaimany Nazar University of Isfahan Fatemeh Cheshmberah University of Isfahan Mehrdad Farhadian University of Iran Journal Article 2016 07 06 An aquaculture system can be a potentially significant source of antibacterial compounds and ammonia in an aquatic environment. In this study, the removal of total ammonia nitrogen and florfenicol antibiotic from synthetic aqueous wastewater was assessed by applying a commercial TFC (thin film composite) polyamide nanofilter. The effects of pH (6.5-8.5), pressure (4-10 bar), concentration of total ammonia nitrogen (1-9 mg/L), and florfenicol (0.2-5 mg/L) on the removal efficiency of the nanofilter were studied at a constant 70% recovery rate. It was found that by increasing the pH within the range of 6.5 to 8.5, it enhanced the removal efficiency by up to 98% and 100% for total ammonia nitrogen and florfenicol, respectively. With an increase in pressure from 4 to 7 bar, the removal percentage increased and then, it decreased from 7 to 10 bar. The interactions factors did not have significant effects on the both pollutants removal efficiencies. To obtain optimal removal efficiencies, an experimental design and statistical analysis via the response surface method were adopted.<strong></strong> https://aet.irost.ir/article_389_8f8f842200b7520d9de884af8c0a3d84.pdf

Iranian Research Organization for Science and Technology Advances in Environmental Technology 2476-6674 2 2 2016 04 01 Removal of As(V), Cr(VI) and Pb(II) from aqueous solution using surfactant-modified Sabzevar nanozeolite 105 109 398 10.22104/aet.2016.398 EN Kourosh Razmgar Department of chemical engineering, Ferdowsi University Zahra Beagom Mokhtari Hosseini Department of Chemical Engineering, Hakim Sabzevari University Journal Article 2016 08 04 The pollution of water environments is a challenging issue especially in developing countries. Contamination of drinking water with heavy metals has been reported in many parts of the world. Arsenic, chromium and lead are dangerous heavy metals and also common contaminants of drinking water. In this study, the capacity and performance of the surfactant-modified Sabzevar natural nanozeolite (SMSNZ) on the removal of heavy metals from an aqueous solution was investigated. Initially, the appropriate concentration of hexadecyltrimethylammonium bromide HDTMA-Br solution for modification was investigated; it was found that it must be higher than the critical concentration micelle (CMC). Then, the removal of As (V), Cr (VI), and Pb(II) from an aqueous solution was studied using SMSNZ. The results indicated that the removal efficiency was very high in different initial concentrations of heavy metals. The Linear, Langmuir and Freundlich isotherm models were used to investigate the adsorption equilibrium of the surfactant-modified natural zeolite for heavy metals adsorption. The results showed that the Linear isotherm is a better fit for the three studied heavy metals. https://aet.irost.ir/article_398_8d6da3d2387586ccce1a62bb13ad0012.pdf