List of Articles اکسیداسیون

• Open Access Article
  • Abstract Page
  • Full-Text
  
  1 - Evaluation of the efficiency of the advanced aerobic process by the Moving bed bioreactor (MBBR) method in wastewater treatment of detergent production industries
  saeed poorkareem Fariba Ostovar Kamran Taghavi
  Abstract In this study, the aerobic biological process was investigated by the moving bed bioreactor (MBBR) method for wastewater treatment of detergent industries. The mean of COD and LAS in raw wastewater were 10231 mg/L and 210 mg/L, respectively. In this study, th More

  Abstract In this study, the aerobic biological process was investigated by the moving bed bioreactor (MBBR) method for wastewater treatment of detergent industries. The mean of COD and LAS in raw wastewater were 10231 mg/L and 210 mg/L, respectively. In this study, three different concentrations of LAS (210, 500, and 1000 mg/L) were used to determine the efficiency of the whole system in removing COD and LAS. The BOD5/COD ratio increased from 0.2 in raw wastewater to 0.45 after pretreatment. In the MBBR system in reactor 1 with 36 hours of hydraulic rate time (HRT), the highest removal efficiencies of 93.41% and 95% were obtained for COD and LAS, respectively. In Reactor 2 with similar conditions to HRT of 36 hours, the highest removal efficiencies for COD and LAS were 94.20% and 99.99%, respectively. By changing the amount of injected air from 30 L/min to 50 L/min and then 70 L/min, the removal efficiency in the amount of air injected about 50 L/min was increased. Organic charge loading (OUR) studies also showed a reduction in specific oxygen consumption from about 11 mg O2/gr MLSS.hr at the beginning of the operation period to about 2 mg O2/gr MLSS.hr at the end of the period. This study showed that the MBBR process, can meet the environmental output standards for the treatment of detergent industry wastewater and be used as an efficient method in detergent industry wastewater treatment. Manuscript profile
• Open Access Article
  • Abstract Page
  • Full-Text
  
  2 - Studying structural properties of polyethylene waxes with infrared spectroscopy
  Mina Alizadehaghdam
  Polyethylene waxes are ethylene oligomers with unique properties, high crystallinity, linearity and low solubility in the solvents which provides a variety of applications in different industries such as electrotechnique, rubber, textile, fertilizer production, etc. Inf More

  Polyethylene waxes are ethylene oligomers with unique properties, high crystallinity, linearity and low solubility in the solvents which provides a variety of applications in different industries such as electrotechnique, rubber, textile, fertilizer production, etc. Infrared spectroscopy (FTIR) is a simple and common analysis to examine the chemical and physical properties of polyethylene such as structure identification, chemical composition and crystallinity evaluation. Physical properties of a polyethylene wax largely depends on its branching degree. Absorption at the wavelength 1378 cm-1 associated with methyl groups symmetric deformation is used for determining the number of branches. Rocking vibration of methyl and methylene groups in the wavelength ranges of 800-1200 cm-1 and 720-770 cm-1 respectively are applied for identification of the branch type. Absorption of vinyl, trans vinylene and vinylidene unsaturation and carbonyl groups introduced into the structure by wax oxidation, were investigated. Absorption intensity was related to the number of absorbing species by molar absorption parameter or absorption coefficient based on the Beer-Lambert law. Some experimental relations were also introduced based on nuclear magnetic resonance spectroscopy. Deconvolution of the double absorption in the range 720-730 cm-1, associated with rocking vibration of methylene groups, to the crystalline and amorphous bands led to the crystallinity estimation. Manuscript profile