The ozonation of extremely polluted petrochemical wastewater: Effect of catalysts, initial pH, volumetric flow rate and concentration of ozone on oxidation rate
Journal Title: Journal of Biodiversity and Environmental Sciences (JBES) - Year 2015, Vol 6, Issue 1
Abstract
Ozonation of an extremely polluted petrochemical wastewater from styrene and propylene oxide production and the influence of different factors on the treatment efficiency were investigated. The treatment efficiency was the highest under alkaline conditions and with the use of catalysts. Optimal values of ozone concentration and volumetric flow rate of the ozone-oxygen mixture were 20 mg L–1 and 400 L (L × h)–1, respectively. The use of H2O2 (0.075 wt%) as a catalyst allowed the maximum COD conversion (93%) and acetophenone removal (98%) to be achieved after 60 min. In the meantime, at an optimal concentration of MnSO4.5H2O (0.1 wt%), the treatment efficiency in terms of COD and acetophenone removal increased up to 85% and 84%, respectively. Acetophenone was completely removed from the wastewater when the ozonation time was increased to 90 min, using H2O2 or MnSO4.5H2O as a catalyst, while phenol, styrene, and ethylbenzene were entirely removed after 60 min. During the ozonation process an abnormal increase in pH appeared due to •OH-radical formation. This interesting phenomenon resulted in the possibility of increasing the treatment efficiency by lengthening the time during which the maximum pH as well as the maximum quantity of •OH-radicals were observed.
Authors and Affiliations
Quyen Ngo, Linh Dao, Evgeniy Grigoriev, Alexandr Petukhov
Investigation of forest area and density changes in Middle Zagros using aerial photos interpretation and GIS in the various distances of the village (a case study: Kakareza region, Lorestan province)
This study located in the Oak trees coppice of kakareza situated on 45th kilometers on the way to Aleshtar from northeast of Khorramabad at the middle area of zagros. In this study cognitional changes (area and accumula...
Responses of morphological characteristic and grain yield of maize cultivars to water stress at reproductive stage
In order to evaluate some morphological and grain yield of maize cultivars (S704, BC678 and H500) under water stress at grain filling stage (no stress and stress), a factorial experiment (using RCB design) with three re...
Leaf epidermal anatomy of dominant aquatic plant species in Swat Valley, Pakistan
Total 21 species (15 genera and 12 botanical families) were studied for their foliar anatomy for the first in district Swat, Pakistan because the said plants have multiple diagnostic economic importance and foliar anatom...
Evaluation of Water Intake Structures for Municipal Water Supply Scheme in Lagos, Nigeria.
The aim of this study was to evaluate some of the grass root problems that tend to frustrate municipal water supply efforts of the Lagos State Water Corporation. This was achieved by understudying three water withdrawal...
Essential Oil Variation within and between Stachys inflata Benth. and Stachys lavandulifolia Vahl. Populations from Iran
Although several species of Stachys possess characteristic essential oils, only a few published studies have described within and between populations of their volatile constituents. The aim of the present study was to ev...