Research Output
1 - 10 of 84
Publication
The reaction of wastewater treatment and power generation of single chamber microbial fuel cell against substrate concentration and anode distributions
2020-12-01
,
Tan S.M.
,
Ong Soon An
,
Ho Li Ngee
,
Wong Yee Shian
,
Thung W.E.
,
Teoh T.P.
This study demonstrated the effectiveness of single chamber up-flow membrane-less microbial fuel cell (UFML-MFC) in wastewater treatment concurrently with bioelectricity generation. The objectives of this study were to examine the effect of influent substrate concentration (0.405 g/L, 0.810 g/L, 1.215 g/L, 1.620 g/L), anode distributions (11 cm, 17 cm, 23 cm) and surface morphologies for biofilm formation on the performance of wastewater treatment and power generation. The optimum performance was obtained with substrate concentration of 0.810 g/L. The COD removal efficiency, output voltage, internal resistance, power density and current density obtained were 84.64%, 610 mV, 200 Ω, 162.59 mW/m2 and 468.74 mA/m2, respectively. The Coulombic Efficiency (CE), Normalized Energy Recovery (NERS and NERv) were 1.03%, 789.38 kWh/kg COD and 22.56 kWh/m3, respectively. The results also indicate that the output voltage and power generation obtained in a continuous up-flow MFC were higher with A3 (23 cm), which is of larger electrodes spacing followed by A2 (17 cm) and A1 (11 cm) caused by the enrichment of anaerobic microbial population at A1.
Publication
Comparison of Different Cathode Materials for Degradation of Reactive Red 120 and Electricity Generation in Photocatalytic Fuel Cell
2020-10-01
,
Mariaswamy A.J.
,
Ong Soon An
,
Abdul Latif Abdul Rani
,
Ho Li Ngee
In this study, a photocatalytic fuel cell (PFC) based on immobilized zinc oxide (ZnO) on carbon felt photoanode and activated carbon flakes as cathode was designed for the treatment of azo dye, reactive red 120 (RR120) containing wastewater and simultaneous electricity generation. Under light irradiation, generated electron-hole pairs at the photoanode travel via the external circuit to the cathode, thus generating electricity. This was the first attempt where activated carbon flakes were applied as cathode material in PFC. This study examined the influence of parameters such as light irradiation, cathode material, initial dye concentration, supporting electrolytes, pH and concentration of oxidizing agent and hydrogen peroxide (H2O2) on the efficiency of PFC to degrade azo dye of RR120 while generating electricity. Complete decolourization of up to 50 mg/L of RR120 dye was achieved but increased dye concentration significantly reduced the PFC efficiency. The PFC efficiency improved using an amalgamation of supporting electrolytes, pH and oxidizing agent at optimum levels, achieving total dye removal and producing a maximum power density of 18.58 mW/cm2.
Publication
Biotreatment of sulfonated dyestuffs with energy recovery in microbial fuel cell: Influencing parameters, kinetics, degradation pathways, mechanisms, and phytotoxicity assessment
2021-08-01
,
Tan S.M.
,
Ong Soon An
,
Ho Li Ngee
,
Wong Y.S.
,
Che Zulzikrami Azner Abidin
,
Thung W.E.
,
Teoh T.P.
Removal of recalcitrant sulfonated dyestuff intermediates from wastewater has been an urgent challenge for environmental technologies. In this regard, the biodegradations of monoazo Methyl Orange (MO) and diazo dyes Reactive Black 5 (RB5) towards wastewater treatment and bioelectricity generation in microbial fuel cell were investigated and compared through the studies on azo dye concentration, aeration, sampling points arrays, and electrode spacings. The degradation of diazo RB5 yielded higher chemical oxygen demand removal, decolourization efficiencies, and power generation over monoazo MO. The decolourization efficiency of RB5 (97.62%) increased with an increase of RB5 concentration (50 mg/L), suggesting that the system has the capability of removing higher RB5 concentration. However, contrary results were obtained with MO due to its toxicity. This study also demonstrated that the decolourization rate of diazo RB5 (0.1533 h-1) was ≈ 53% higher than monoazo MO (0.0727 h-1). The findings revealed that the degradation kinetic was remarkably influenced by the chemical structure of dye, where dye with more electron-withdrawing groups at para position are more susceptible to be reduced. Higher output voltage (568.59 mV) and power generation (108.87 mW/m2) were attained with RB5 due to electron donor availability and electron-shuttling characteristics of RB5 decolourized intermediates. Furthermore, detailed degradation pathways of MO and RB5 were presented based on the UV-vis and GC-MS results. The phytotoxicity assessment via Sorghum bicolor seeds had further verified the reduction in toxicity after the treatment of azo dyes.
Publication
Intermolecular degradation of aromatic compound and its derivatives via combined sequential and hybridized process
2023-03-01
,
Lau Y.Y.
,
Wong Yee Shian
,
Ong Soon An
,
Nabilah Aminah Lutpi
,
Sam Sung Ting
,
Teng T.T.
,
Eng K.M.
The under-treated wastewater, especially remaining carcinogenic aromatic compounds in wastewater discharge has been expansively reported, wherein the efficiency of conventional wastewater treatment is identified as the primary contributor source. Herein, the advancement of wastewater treatments has drawn much attention in recent years. In the current study, combined sequential and hybridized treatment of thermolysis and coagulation–flocculation provides a novel advancement for environmental emerging pollutant (EP) prescription. This research is mainly demonstrating the mitigation efficiency and degradation pathway of pararosaniline (PRA) hybridized and combined sequential wastewater treatment. Notably, PRA degradation dominantly via a linkage of reaction: thermal cleavage, deamination, silication and diazene reduction. Thermolysis acts as an initiator for the PRA decomposition through thermally induced bond dissociation energy (BDE) for molecular fragmentation whilst coagulation–flocculation facilitates the formation of organo-bridged silsesquioxane as the final degradation product. Different from conventional treatment, the hybridized treatment showed excellent synergistic degradability by removing 99% PRA and its EPs, followed by combined sequential treatment method with 86% reduction. Comprehensive degradation pathway breakdown of carcinogenic and hardly degradable aromatic compounds provides a new insight for wastewater treatment whereby aniline and benzene are entirely undetectable in effluent. The degradation intermediates, reaction derivatives and end products were affirmed by gas chromatography–mass spectrometry, Fourier transform infrared spectroscopy and ultraviolet–visible spectrophotometry (GC–MS, FTIR and UV–Vis). This finding provides valuable guidance in establishing efficient integrated multiple-step wastewater treatments. Graphical abstract: [Figure not available: see fulltext.].
Publication
A highly sustainable hydrothermal synthesized MnO2 as cathodic catalyst in solar photocatalytic fuel cell
2021-01-01
,
Ong Y.P.
,
Ho Li Ngee
,
Ong Soon An
,
Banjuraizah Johar
,
Ibrahim A.H.
,
Thor S.H.
,
Yap K.L.
A unidirectional flow solar photocatalytic fuel cell (PFC) was successfully developed for the first time to offer alternative for electricity generation and simultaneous wastewater treatment. This study was focused on the synthesis of α-, δ- and β-MnO2 by wet chemical hydrothermal method for application as the cathodic catalyst in PFC. The crystallographic evolution was performed by varying the ratios of KMnO4 to MnSO4. The mechanism of the PFC with the MnO2/C as cathode was also discussed. Results showed that the catalytic activity of MnO2/C cathode was mainly predominated by their crystallographic structures which included Mn–O bond strength and tunnel size, following order of α- > δ- > β-MnO2/C. Interestingly, it was discovered that the specific surface areas (SBET) of different crystal phases did not give an impact on the PFC performance. However, the Pmax could be significantly influenced by the micropore surface area (Smicro) in the comparison among α-MnO2. Furthermore, the morphological transformation carried out by altering the hydrothermal duration demonstrated that the nanowire α-M3(24 h)/C with 1:1 ratio of KMnO4 and MnSO4 yielded excellent PFC performance with a Pmax of 2.8680 μW cm−2 and the lowest Rint of 700 Ω.
Publication
Synergistic Effect Between Iron and Food/Microorganism (F/M) Ratio in Biological Wastewater Treatment
2022-01-01
,
Subramaniam L.S.
,
Nabilah Aminah Lutpi
,
Wong Yee Shian
,
Ong Soon An
,
Nazerry Rosmady Rahmat
,
Siripatana C.
Biological wastewater treatment is mainly dependent on the actions of microorganisms that can be used to treat wastewater. Microorganisms will start to stick together when they degrade the organic matter in wastewater for food and flocculate to settle the pollutants. This study aimed to investigate the effect of food to microorganism (F/M) ratio and iron in a biological process using aerobic treatment. For this purpose, four aerobic tanks (A, B, C, D) were set up using activated sludge as the seed sludge, air pump as air diffuser to provide oxygen to the system, and three litres of synthetic medium as carbon source for each tank. A specific amount of iron (II) sulfate was added into tanks B, C, and D with the weight of 3 g, 6 g, and 9 g, respectively. Tank A act as a control, and no iron dosage was added. The F/M ratio for tanks A, B, C, and D were 0.8, 0.5, 0.4, and 0.3 mg BOD/mg MLVSS, respectively. The aerobic tanks were operated for 40 days in sequential batch mode and sampling was collected four times per week to observe the COD and MLVSS. This study has found that Tank D shows the best performance compared to all tanks with 84.71% COD removal efficiency and a fivefold increment of microorganism growth rate. These findings suggest that a relationship exists between the iron and F/M ratio to enhance the aerobic treatment process.
Publication
Influence of Amaranth dye concentration on the efficiency of hybrid system of photocatalytic fuel cell and Fenton process
2017-10-01
,
Noradiba Nordin
,
Ho Li Ngee
,
Ong Soon An
,
Abdul Haqi Ibrahim
,
Wong Yee Shian
,
Sin Li Lee
,
Oon Yoong Sin
,
Oon Yoong Ling
A novel sustainable hybrid system of photocatalytic fuel cell (PFC) and Fenton process is an alternative wastewater treatment technology for energy-saving and efficient treatment of organic pollutants. The electrons generated from PFC photoanode are used to produce H2O2 in the Fenton reactor and react with the in situ generation of Fe2+ from sacrificial iron for hydroxyl radical formation. In this study, the effect of different initial Amaranth dye concentrations on degradation and electricity generation were investigated. ZnO/Zn photoanode was prepared by anodizing method and characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). Results revealed that the maximum power density (9.53 mW/m2) and current density (0.0178 mA/m2) were achieved at 10 mg/L of Amaranth. The correlation between dye degradation, voltage output, and kinetic photocatalytic degradation were also investigated and discussed.
Publication
Enhanced photodegradation of phenol by ZnO nanoparticles synthesized through sol-gel method
2017-12-01
,
Nik Noor Athirah Nik Yusoff
,
Ho Li Ngee
,
Ong Soon An
,
Wong Yee Shian
,
Wan Fadhilah Khalik
,
Fahmi Ridzwan
Zinc oxide (ZnO) utilization in advanced oxidation process (AOP) via solar-photocatalytic process was a promising method for alternative treating wastewater containing phenol. The ZnO photocatalyst semiconductor was synthesized by sol-gel method. The morphology of the ZnO nanostructures was observed by using scanning electron microscope (SEM) and the crystallite phase of the ZnO was confirmed by x-ray diffraction (XRD). The objective of this study was to synthesis ZnO nanoparticles through a sol-gel method for application as a photocatalyst in the photodegradation of phenol under solar light irradiation. The photodegradation rate of phenol increased with the increasing of ZnO loading from 0.2 until 1.0 g. Only 2 h were required for synthesized ZnO to fully degrade the phenol. The synthesized ZnO are capable to totally degrade high initial concentration up until 45 mg L-1 within 6 h of reaction time. The photodegradation of phenol by ZnO are most favoured under the acidic condition (pH3) where the 100% removal achieved after 2 h of reaction. The mineralization of phenol was monitored through chemical oxygen demand (COD) reduction and 92.6% or removal was achieved. This study distinctly utilized natural sunlight as the sole sources of irradiation which safe, inexpensive; to initiate the photocatalyst for degradation of phenol.
Publication
Integrated photocatalytic and sequencing batch reactor (SBR) treatment system for degradation of phenol
2017-04-06
,
Nik Noor Athirah Nik Yusoff
,
Ong Soon An
,
Ho Li Ngee
,
Wong Yee Shian
,
Wan Fadhilah Wan Mohd Khalik
,
Lee Sin Li
This study will examine the efficiency of the simultaneous photocatalytic and biodegradation process in the same treatment reactor. The sequencing batch reactor or also known as SBR is an effective wastewater treatment method that has been applied widely. SBR system has become an alternative method for industrial wastewater treatment with high concentration of chemical oxygen demand (COD), and phenolic compound. In order for the photocatalytic process to occur, ZnO nanoparticles immobilized onto sponge were introduced to the reactor. It was observed that the COD value were decreased, indicated that the simultaneous biodegradation and photodegradation process in functional. The effect of ZnO nanoparticles on the production and composition of extracellular polymeric substances (EPS) and the physiochemical stability of activated sludge in hybrid growth type SBR were monitored. The percentages of removal are varied with different concentration of ZnO nanoparticles. The highest COD removal recorded is 31.5% with concentration of ZnO 0.6 mg/L. With the present of the ZnO nanoparticles, the degradation of phenol was relatively better than combination of biological of photlysis and biological.
Publication
Biohydrogen production from palm oil mill effluent with Moringa Oleifera seeds as support carrier in attached growth system
2020-06-10
,
Hamid W.Z.W.A.
,
Nabilah Aminah Lutpi
,
Wong Yee Shian
,
Ong Soon An
,
Malek M.A.
Biohydrogen production by dark fermentation is one of the attracting alternatives for renewable energy in worldwide. By employing immobilized cells, hydrogen production and cell density could be improved. This study aimed to investigate the efficiency of Moringa Oleifera Seeds (MOS) immobilized cells in enhancing the biohydrogen production using repeated batch fermentation under mesophilic condition, 37°C. The efficiency of MOS as support carrier, effect of the initial pH (5.0-7.0) and performance of raw and diluted Palm Oil Mill Effluent (POME) using MOS immobilized cells were investigated using anaerobic sludge as inoculums. The cumulative hydrogen production results were fitted into a modified Gompertz equation to find the maximum hydrogen production. MOS immobilized cells was more efficient in producing hydrogen compare to suspended cells (without MOS). The optimal pH obtained using MOS immobilized cells was found to be at pH 6 using raw POME with the maximum hydrogen production (Hm) of 122 mL, the maximum hydrogen production rate (Rm) of 39.0 mL/h, and 560 ppm of hydrogen concentration.