Now showing 1 - 10 of 10
  • Publication
    Preliminary screening oxidative degradation methyl orange using ozone/ persulfate
    ( 2018)
    Nur Aqilah Razali
    ;
    ; ; ; ;
    Siti Nasuha Sabri
    ;
    Su Huan Kow
    The present study focusing on the performances of advanced oxidation process by using ozonation method towards Methyl Orange based on the efficiency of colour removal and Chemical Oxygen Demand (COD) removal. Factorial design with response surface methodology (RSM) was used to evaluate the interaction between operational conditions, such as pH, initial concentration, contact time and persulfate dosage to obtain the optimum range conditions using a semi-batch reactor. The range of independent variables investigated were pH (3-11), initial concentration (100-500mg/L), contact time (10-50min) and persulfate dosage (20-100mM) while the response variables were colour removal and COD removal of Methyl Orange. The experimental results and statistical analysis showed all the parameters were significant. Thus, from this findings, optimization of operational conditions that had been suggested from the ozone/persulfate RSM analysis were (pH 3, 100 mg/L, 50min, 60mM) that would be produced 99% Colour Removal and 80% COD Removal and help in promoting an efficient ozonation process. The effect list data that showed the most contributed effects to increase the percentages of colour removal were pH and persulfate dosage whereas the contact time and initial concentration had the highest positive effects on the COD removal. Other than that, the interaction between pH, contact time and persulfate dosage were found to be the most influencing interaction. Therefore the least influencing interaction was interaction between persulfate dosage and pH. In this study, the correlation coefficient value R2 for colour removal and COD removal of Methyl Orange were R2= 0.9976 and R2= 0.9924 which suggested a good fit of the first-order regression model with the experimental data.
  • Publication
    Electro-oxidation as Tertiary Treatment Techniques for Removal of Palm Oil Mill Effluent
    The production of palm oil, though, results in the generation of huge quantities of polluted wastewater normally referred as palm oil mill effluent (POME). It gives adverse impacts to the environment, particularly if it is not properly treated. POME are known to have various types of liquids, residual oil and suspended solid as it has very high strength waste in its untreated form. Although conventional biological processes are normally efficient for the degradation of pollutants occurring in wastewater, most of these compounds are not effectively removed. As a result, further treatment is needed to meet more stringent discharge standards of Department of Environment (DOE), Malaysia. This research focused on treatment of POME by using electro-oxidation process (EO). It was done to identify the performance of EO process for colour, chemical oxygen demand (COD), suspended solids (SS), and Ammoniacal-nitrogen NH3-N) removal as well as the relative effects of different operational parameters such as pH, type of electrodes and contact time. The pH was varied between 3 and 11, using Ferum (Fe) and Aluminium (Al) electrode, and contact time from 0 to 120 min. The most suitable pH, contact time and type of electrode were pH 3, 120 min and Aluminium electrode, respectively. Therefore, EO process at specified level can be used as an efficient and effective post-treatment technology to meet the standard regulatory requirements.
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  • Publication
    Influence of leachate matrix on oxidation performance of ozonation and aops
    Landfill leachate is a critical environmental issue that should be adequately treated to prevent it from spreading to the environment. This study explored the influence of raw leachate matrix and treated leachate matrix on O3, O3/H2O2, and O3/PS performance. O3 and AOPs were conducted in a laboratory-scale batch reactor. The findings showed the degradation of p-cresol, COD, and humic substances was much slower in treated leachate matrix than in raw leachate matrix. However, color was found easier to remove in treated leachate. The results revealed a synergic effect between molecular O3 and dissolved organic matter in the raw leachate as the O3 performance was enhanced in the presence of raw leachate matrix, except for color removal. The highest degradation of more than 90% was achieved in O3 /H2 O2 to remove COD, p-cresol, and humic substances, although it is the most affected by the leachate matrix. This study provides vital insight into the notable performance of O3 /PS in color removal regardless of the influence of leachate matrix, suggesting that the sulfate radical-induced oxidation outperformed O3 and O3 /H2 O2 in reducing nitrogen-containing compounds.
      1
  • Publication
    Removal of palm oil mill effluent by using electro-oxidation process
    ( 2020-06-10) ;
    Sabri S.N.
    ;
    ;
    Bashir Mohammed J.K.
    ;
    ; ;
    Mohamed Hussein N.F.
    ;
    Mahiran N.Q.
    Wastewater includes the Palm Oil Mill Effluent (POME) that gives adverse impacts to the environment especially for water pollution when it is not treated properly. POME are known to have various types of liquids, residual oil and suspended solid as it has very high strength waste in its untreated form. Although conventional biological processes are normally efficient for the degradation of pollutants occurring in wastewater, most of these compounds are not effectively removed. As a result, further treatment is needed to meet more stringent discharge standards of Department of Environment (DOE). This research focused on treatment of POME by using electro-oxidation process (EO). It was done to identify the performance of EO process for colour, chemical oxygen demand (COD), suspended solids (SS), ammoniacal-nitrogen (NH3-N), and turbidity removal as well as the relative effects of different operational parameters such as pH, type of electrodes and contact time. The pH was varied from 3 to 11, the electrodes were aluminium and iron and the contact time was from 0 to 120 min. The most suitable pH, contact time and type of electrode were pH 3, 120 min and Al electrode.
      1
  • Publication
    Treatment of O3 with Na2S2O8 by ANOVA Interpretation towards degradation of azo dye
    Advanced oxidation processes (AOPs) especially ozonation method is widely studied in the wastewater treatmentfield. In this study, it highlighted about threemainenvironmental issues in the world such as1) proposing a method to overcome uncontrollable effluents from textile industriesby using syntheticdyes; 2)creating an improvementof previous conventional method; 3) reduced process time by using statistical approach.To address with this issue, analysis of variance (ANOVA)from Response Surface Methodology (RSM)to study the performance of O3with the help of persulfate (Na2S2O8) for treating one of azo dyes which is Reactive Green 19.This is due to there isvery limited work done by statistical analysis on this study. Hence, ANOVA data would proposestatistical models tailored to the data in 2D and 3D contour plots by knowing the three influenced parameterswhich is pH(6 to 10),persulfate concentration (30to 70mM) and contact time (4 to 20 min). Through the analysis, the result can be concluded that improvement of ozonation process with persulfate (Na2S2O8) werestatistically significant after allinteractive effectsgave a positive feedback towards responses.The obtained optimum conditions included a persulfate concentration (49mM), initial pH (8.89) and contact time (18 min) with fixed initial concentration 100mg/L. The experimental results were corresponded well with predicted models colour removal rates which is 99%.
      18  22
  • Publication
    Study of O3/S2O82- Advanced Oxidation Processes (AOPs) for removal of dye industrial effluents
    This research was carried out to study the efficiency of O3/S2O82- system in removal of Reactive Red 120 (RR120) dye sample. Different operating parameter such as pH, initial dye concentration and persulfate dosage were studied to evaluate the performance on removing colour and COD. The removal of colour and COD achieved higher efficiency at pH 7, 100 mg/L of initial dye concentration and persulfate dosage of 5 g S2O82-/1 g RR120. O3/S2O82- with the most effective conditions experienced effective decolourization and degradation of organic pollutants than O3 only. Furthermore, it achieved faster breakdown of azo bond and aromatic groups than O3 after treatment as observed with UV-Vis absorption spectra. The FT-IR analysis obtained new absorption peak that represents alkenes after 20 min of O3 treatment whereas mostly of the absorption bands of O3/S2O82- flattened.
      1  6
  • Publication
    Reactive Green 19 degradation using O3/S2 O8(2-) process: Intermediates and proposed degradation pathway
    ( 2022-01-01)
    Mohd Razali N.A.
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    ; ; ; ;
    Siti Nasuha Sabri
    ;
    Kow Su Huan
    ;
    Safya Abdul Malik
    The massive drawbacks of conventional wastewater treatment have led to a demand investigation about new advanced wastewater treatment technology. The issue can be addressed via advanced oxidation processes (AOPs) as witnessed recently. Therefore, the objective of this study was to investigate the performance of ozone/persulfate ((Formula presented.)) process to assess its use as potential degradation of diazo dye which is Reactive Green 19 (RG19). In this work, efficiency, color, and COD removal were investigated over a range of initial pH, persulfate concentration and initial concentration of RG19. The amount of sodium persulfate ((Formula presented.)) was varied at different levels (20–100 mM) relative to precursor radical to assess the optimum usage of persulfate concentration for RG19 degradation. Evidence that RG19 could degrade efficiently had occurred at 100 mg/L, initial pH 9, 60 mM persulfate concentration was identified by FTIR and GC/MS analysis. The results revealed that RG19 could achieve complete decolorization easily as compared to mineralization. In addition, RG19 degradation pathway gave the best representation of level degradation. The GC/MS and FTIR results exhibited the proposed RG19 degradation pathway that involved the characteristic of sulfonic group, (Formula presented.) accompanied with (Formula presented.) became as an indicator of their structure broken down one by one. The degradation products such as oxalic acid, formic acids and others were analyzed and finally converted to carbon dioxide and water. The diazo dye structure itself aided with (Formula presented.) has its superior characteristic as an aid for the efficient degradation process.
      1
  • Publication
    Influence of leachate matrix on oxidation performance of ozonation and aops
    Landfill leachate is a critical environmental issue that should be adequately treated to prevent it from spreading to the environment. This study explored the influence of raw leachate matrix and treated leachate matrix on O3, O3/H2O2, and O3/PS performance. O3 and AOPs were conducted in a laboratory-scale batch reactor. The findings showed the degradation of p-cresol, COD, and humic substances was much slower in treated leachate matrix than in raw leachate matrix. However, color was found easier to remove in treated leachate. The results revealed a synergic effect between molecular O3 and dissolved organic matter in the raw leachate as the O3 performance was enhanced in the presence of raw leachate matrix, except for color removal. The highest degradation of more than 90% was achieved in O3 /H2 O2 to remove COD, p-cresol, and humic substances, although it is the most affected by the leachate matrix. This study provides vital insight into the notable performance of O3 /PS in color removal regardless of the influence of leachate matrix, suggesting that the sulfate radical-induced oxidation outperformed O3 and O3 /H2 O2 in reducing nitrogen-containing compounds.
      1
  • Publication
    Recovery of nano-lignin from anaerobic treated palm oil mill effluent (AT-POME)
    Lignin is the main polymers in woody biomass aside cellulose and hemicelluloses Recently, nano-lignin is gaining importance due to the increasing demand for bio-based and bio-active nanomaterial fillers for many applications such as in composite and textile industries. Palm oil mill effluent (POME) is the main wastewater produce by palm oil mills. Anaerobically treated (AT-POME) contains high soluble lignin due to the anaerobic digestion of cellulosic material in POME. Nano-lignin was precipitated by adjusting the initial pH of AT-POME during the sonication process. Sulfuric acid (H2SO4), nitric acid (HNO3), hydrochloric acid (HCl) and phosphoric acid (H3PO4) were used to adjust the initial pH of AT-POME. Result shows that sulfuric acid was the most suitable acid to be used as it could recovered 96% of the soluble lignin in AT-POME. The presence of ultrasonic during the precipitation process had reduced the size to 383.4 nm. The optimum operating parameter for lignin recovery is at pH 4 using sulfuric acid and sonicated at 80 watts for 15 minutes. This study shows that sonication could reduce the size of precipitated lignin from AT-POME. In addition, removal of lignin from AT-POME also reduced the COD content of AT-POME.
      3  1
  • Publication
    Improvement of oxygen transfer efficiency in the activated sludge process
    ( 2020-06-10)
    Kan S.L.E.
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    ;
    Shum K.J.
    ;
    ; ;
    Kusuma B.S.
    Sequential batch reactor (SBR) is a feasible and economically attractive alternative to continuous activated sludge process to remove pollutants (dynamics and flexibility). Most of the power consumption is consumed by the aeration system to aid the removal of contaminants. Therefore, an optimal aeration system must be proposed to ensure cost-effective and efficient treatment of wastewater. The objective of this study is to evaluate the effect of air flow rate on the oxygen transfer efficiency of the SBR reactor. Based on the results, the removal efficiency of COD and AN at an air flow rate of 7.0 LPM (5.0 mg/L) were slightly higher than the air flow rate of 5.0 LPM (4.0 mg/L). However, the improvement is not exceptional. Excessive DO level and aeration should be avoided to achieve cost-effective yet efficient removal of pollutants.
      2