Pretreatment of stabilized leachate using ozone/persulfate oxidation process

Chemical Engineering Journal (Impact Factor: 4.32). 01/2013; 221. DOI: 10.1016/j.cej.2013.02.038


A combination of ozonation and persulfate ðO3=S2O2� 8 Þ was used to treat stabilized landfill leachate. COD,
color, and NH3–N, ozone and persulfate doses, pH and reaction time were evaluated to define the optimum
operational conditions. The results indicated that under optimum operation conditions (i.e.
210 min of ozonation, a COD=S2O2� 8 ratio (1 g/7 g), and pH 10), the best removal values of COD, color,
and NH3–N were 72%, 93%, and 55%, respectively. The biodegradability (BOD5/COD ratio) has improved
from 0.05 to 0.29. The ozone consumption for COD removal was 0.76 kg O3/kg COD. The results obtained
by employing the combined use of persulfate and ozone were compared with those by employing ozone
only and persulfate only. The results achieved with the combined use of persulfate and ozone were compared
with those obtained with ozone only and persulfate only. The combined method (i.e., O3=S2O2� 8 )
achieved higher removal efficiencies for COD, color, and NH3–N compared with other studied applications.
Additionally, the combined of ozone/persulfate method proved to be more efficient than the combined
use of ozone/Fenton in advanced oxidation processes in the treatment of the same studied leachate.

202 Reads
  • Source
    • "Abu Amr et al. (2013a) used ozone gas to initiate sulfate radical from persulfate during ozonation of stabilized leachate . Ozone cannot react directly with persulfate; however, at high pH (11), significant amount of ozone applied will dissociate and produce hydroxyl radicals which will be involved in the activation of persulfate during ozonation (Abu Amr et al., 2013a,b). "
    [Show abstract] [Hide abstract]
    ABSTRACT: The current study investigated the effects of S2O8(2-) and S2O8(2-)/H2O2 oxidation processes on the biodegradable characteristics of an anaerobic stabilized leachate. Total COD removal efficiency was found to be 46% after S2O8(2-) oxidation (using 4.2g S2O8(2-)/1g COD0, at pH 7, for 60min reaction time and at 350rpm shaking speed), and improved to 81% following S2O8(2-)/H2O2 oxidation process (using 5.88g S2O8(2-) dosage, 8.63g H2O2 dosage, at pH 11 and for 120min reaction time at 350rpm). Biodegradability in terms of BOD5/COD ratio of the leachate enhanced from 0.09 to 0.1 and to 0.17 following S2O8(2-) and S2O8(2-)/H2O2 oxidation processes, respectively. The fractions of COD were determined before and after each oxidation processes (S2O8(2-) and S2O8(2-)/H2O2). The fraction of biodegradable COD(bi) increased from 36% in raw leachate to 57% and 68% after applying S2O8(2-) and S2O8(2-)/H2O2 oxidation, respectively. As for soluble COD(s), its removal efficiency was 39% and 78% following S2O8(2-) and S2O8(2-)/H2O2 oxidation, respectively. The maximum removal for particulate COD was 94% and was obtained after 120min of S2O8(2-)/H2O2 oxidation. As a conclusion, S2O8(2-)/H2O2 oxidation could be an efficient method for improving the biodegradability of anaerobic stabilized leachate. Copyright © 2015 Elsevier Ltd. All rights reserved.
    Waste Management 08/2015; 44. DOI:10.1016/j.wasman.2015.07.046 · 3.22 Impact Factor
  • Source
    • "These phenomena under MW/SPS and MW/H2O2 were attributed to the ability of H2O2 and SPS to absorb and transmit microwave irradiation in alkaline pH more a little than other pHs. Subsequently more radicals are produced in this condition [21-25]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Pentachlorophenol (PCP) is one of the most fungicides and pesticides used in wood protection. Poisoning from PCP may be happened in dermal absorption, and respiration or ingestion. With regard to health and environmental effects of PCP, many methods were studied for its removal. Microwave assisted other methods are environmental friendly, safety, and economical method, therefore, in this study; a modified domestic microwave assisted hydrogen peroxide (MW/H2O2) and sodium persulfate (MW/SPS) was used for PCP removal from aqueous solutions. PCP removal rate was measured under different factors such as pH, energy intensity, SPS, H2O2 concentration, Tert- butyl alcohol (TBA) and chemical oxygen demand (COD). The concentration changes of PCP were determined using spectrophotometer and HPLC spectra, respectively. The best removal PCP rate obtained in condition of pH of 11, 0.02 mol L(-1) of SPS, 0.2 mol L(-1) of H2O2 and energy intensity of 600 W. Moreover, COD removals in MW/H2O2 and MW/SPS process were 83% and 94%, respectively, also TBA test decreased 15% and 3% of PCP removal in MW/SPS and MW/H2O2 processes respectively. Experimental results indicated that sulfate radical was stronger than hydroxyl radical and examinations order reaction was in first order. In this study, was cleared that MW/SPS process was more effective than MW/H2O2 process in PCP removal.
    Journal of Environmental Health Science and Engineering 06/2014; 12(1):94. DOI:10.1186/2052-336X-12-94 · 0.50 Impact Factor
  • Source
    • "These phenomena are attributed to the ability of O 3 to initiate hydroxyl radical formation at high pH. These hydroxyl radicals have an oxidation potential (E° = 2.80) higher than O 3 (E° = 2.07) in the direct reaction under acidic conditions [71]. Conversely, under acidic conditions, the selective reaction of ozonation involves only the ozone with unsaturated organic compounds. "
    [Show abstract] [Hide abstract]
    ABSTRACT: The effluents of some pulp and paper processes are potentially pollutant, because of their large volume and their refractory nature. Biological processes generally are not capable to remove these compounds. Advanced Oxidation Processes (AOP) are characterized by the capability of exploiting the high reactivity of HO • radicals. AOP can produce a total mineralization, transforming recalcitrant compounds into inorganic substances (CO 2 and H 2 O 2), or partial mineralization, transforming them into more biodegradable substances. The high reactivity and low selectivity of these radicals are useful attributes that that make these processes in promising technologies. Due to the differences between pulping processes, the effluents from the various processes and operations of such industries also differ from each other, so that some oxidative processes should be combined to improve the removal efficiency. For the effective oxidation of refractory organic compounds, hydroxyl radicals should be generated continuously in situ due to its chemical instability. Generation of HO • is commonly accelerated by combining oxidizing agents. Among these treatments, UV radiation plus hydrogen peroxide (UV/H 2 O 2), Fenton's reagent (H 2 O 2 /Fe +2), photo-Fenton (UV/H 2 O 2 /Fe +2), and ozone in different combinations (O 3 /UV; O 3 /H 2 O 2) are considered to be effective for the oxidation of effluents from pulp and paper industries.
Show more