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1

Removal of reactive blue 29 dye by adsorption on modified chitosan in the presence of hydrogen peroxide

Naghizadeh A., Nabizadeh R.

Environment Protection Engineering

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2016

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Vol. 42, nr 1

149--168

EN

Industrial effluents that carry dyestuff into natural water systems are serious environmental concern. Complex aromatic structures of dyes make them more stable and more difficult to remove from the effluents discharged into water bodies. In the present study, removal of reactive blue 29 dye with chitosan and modified chitosan with Cu complexes from aqueous solution was investigated in a batch adsorption system with respect to the changes in the contact time, pH of solution and chitosan dosage. Adsorption isotherms of the dye onto chitosan were also studied. The results revealed that the adsorption capacity of chitosan with Cu complexes is lower than that of chitosan without Cu complexes. Also effect of H2O2 on adsorption when we used chitosan without Cu complexes is more considerable. The results also demonstrated that adsorption capacity of reactive blue 29 dye on chitosan was higher at lower pHs. Finally, the Langmuir isotherm showed the best conformity to the equilibrium data.

2

Upgrading the effluent quality of an aerated lagoon with horizontal roughing filtration

Nabizadeh R., Naddafi K., Khazaei M., Fard R. F., Izanloo H., Yavari Z.

Environment Protection Engineering

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2015

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Vol. 41, nr 3

121--136

EN

Removal of suspended solids and microorganisms from an aerated lagoon effluent with a horizontal roughing filter (HRF) was investigated. The aerated lagoon receives Qom municipal wastewater. The HRF was operated at three filtration rates of 0.5, 1.0 and 1.5 m3/(m2·h) during four month operation period. The measured values of turbidity, TSS, COD, pH, temperature and flow rate of HRF at the former filtration rate were 79±12 NTU, 100±11 mg/dm3, 190±12 mg/dm3, 7±0.1 °C, 17±8 °C and 0.82 dm3/min, respectively. The differences between inlet and outlet values of pH and temperature were not significant (P > 0.05). Measures turbidity, TSS and COD in HRF final effluent were 15±13.7 NTU, 37±295 mg/dm3, 64±39.7 mg/dm3, respectively, which corresponds to 81.1%, 63% and 66.3% removal efficiencies, respectively. A decrease of removal efficiency was observed upon increasing filtration rates. The Spearman correlation coefficients between the head-loss and removal efficiencies ranged from 0.578 to 0.968 pointing to a direct relationship. Results of modeling approach revealed appropriate compliance between the values of the observed and predicted TSS for higher filtration rates.

3

Kinetics of degradation of perchloroethylene under ultrasonic irradiation and photooxidation in aqueous solution

Kargar M., Nabizadeh R., Naddafi K., Nasseri S., Mesdaghinia A., Mahvi A. H., Alimohammadi M., Nazmara S.

Environment Protection Engineering

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2013

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Vol. 39, nr 4

29--38

EN

Sonolysis and photodegradation of various compounds such as chlorinated aliphatic hydrocarbons are the recent advanced oxidation processes. Perchloroethylene PCE is one of these compounds mainly used as a solvent and degreaser. In this work, elimination of perchloroethylene in aqueous solution by ultrasonic irradiation and photooxidation by UVC were investigated. Head space gas chromatography with FID detector was used for analyses of PCE. Results showed that PCE could be effectively and rapidly degraded by ultrasonic irradiation, photooxidation by UVC and combination of these methods. The order of studied reactions for degradation PCE has been determined.

4

Potential of granulated modified nanozeolites Y for MTBE removal from aqueous solutions: Kinetic and isotherm studies

Ghadiri S. K., Nabizadeh R., Mahvi A. H., Nasseri S., Mesdaghinia A. R., Talebi S. S.

Polish Journal of Chemical Technology

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2012

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Vol. 14, nr 2

1-8

EN

Adsorption of methyl tert-butyl ether (MTBE) from aqueous solutions by granulated modifi ed nanozeolites Y was investigated. Nanozeolite Y powders were converted into granulated zeolites and subsequently modifi ed with two cationic surfactants (20 mmol/dm3), to be used as adsorbent. Granulated nanozeolites were characterized by BET surface area analysis, elemental analysis and X-ray diffractometer. Hexadecyltrimethylammonium (HDTMA-Cl) modifi ed granulated zeolite had more effective performance than N-cetylpyridinium bromide (CPB) modifi ed granulated zeolite. The most conventional adsorption isotherms and kinetic models were applied to describe MTBE adsorption and reaction dynamic, respectively. The equilibrium sorption data fi tted the Langmuir 2 isotherm model and the kinetic study was followed the pseudo-second-order model. The maximum adsorption capacities for HDTMA-Cl modifi ed zeolite and CPB modifi ed granulated zeolite were 333.33 and 142.8 mg/g, respectively as calculated by the Langmuir model. This study demonstrated that the removal of mtbe by granulated modifi ed nanozeolites Y is a promising technique.