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Abstract: The adsorption of SO2 and NO onto palm shell activated carbon supported with cerium oxide (Ce/PSAC) was studied in a fixed bed adsorber. This paper reports the adsorption equilibrium of SO2 and NO in a simulated flue gas on Ce/PSAC. The experimental results show that within the experimental conditions at different inlet concentration of SO2/NO, the adsorption capacities of Ce/PSAC can be well fitted by Langmuir compared to Freundlich adsorption isotherms. The binary mixtures of SO2 and NO at different initial concentration can be well-correlated by the extended Jain and Snoeyink (JS) Langmuir model compared to extended Langmuir model. The physical properties of Ce/PSAC were calculated and it was consistent with the isotherm parameters obtained from the adsorption results. The adsorption was controlled by physisorption. [Copyright &y& Elsevier]

Abstract: The simultaneous removal of SO2 and NO from simulated flue gas by cerium oxide supported over palm shell activated carbon (Ce/PSAC) was studied in a fixed bed adsorber. The effects of adsorber temperature, presence of humidity, feed gas concentration and space velocity were studied as the process parameter. The results were illustrated as sorption breakthrough curves. From the experimental results, it was found that at higher space velocity, the SO2 and NO sorption capacity was reduced. Humidity enhanced the SO2 sorption capacity but deterred the NO sorption at percentage more than 15%. Temperature played an important role in the simultaneous removal of SO2 and NO by cerium supported over PSAC. The maximum simultaneous sorption capacity of SO2 and NO was achieved at temperature 150°C with 121.7 and 3.5mg/g, respectively. This study shows that cheap biomass based activated carbon can be a potential sorbent for simultaneous removal of SO2 and NO from flue gas. [Copyright &y& Elsevier]

Abstract: The present study is intended for the first time to completely replace the inorganic coagulants with organic polymers in palm oil mill effluent (POME) pretreatment by using direct flocculation of single and dual polymer systems under applied shear. The efficiency of direct flocculation of POME was investigated by using the Population Balance Model (PBM) which considered the charge neutralization and bridging attraction under applied shear. The collision efficiency was calculated based on the Derjaguin Landau Verwey Overbeek (DLVO) theory which considered the effect of adsorbed polymer layers on van der Waals attraction and bridging attraction. This is the first attempt to correlate the floc size distribution from PBM to the indirect indicators of COD, suspended solids, oil and grease. The model predictions are in close agreement with the experimental results for both single and dual polymer systems. The interaction energy curves based on PBM shows that the flocculation using cationic polymer is by charge neutralization and bridging attraction whereas flocculation using anionic polymer is by only bridging attraction. At the optimum flocculation conditions, 99.66%, 55.79%, 99.74% and 80.78% of suspended solids, COD, oil and grease removal and water recovery are achieved, respectively. The direct flocculation process significantly reduced the treatment cost by a factor of 3.6 compared to the conventional coagulation–flocculation process. [Copyright &y& Elsevier]

Abstract: A membrane transport model suitable for the multiple solutes system in reverse osmosis is developed for unsteady-state simulation and prediction of membrane filtration dynamics in terms of permeate flux and concentration of each solute. This model is based on coupling the concentration polarization model using unsteady-state differential material balance and extended Spiegler-Kedem model. This model is characterized by the parameters solute diffusivity in the concentration polarization layer (D bi ), reflection coefficient (σ i ), osmotic constant (a i ), hydraulic permeability constant (L p), mass transfer coefficient (k i ) and solute permeability coefficient (P ii ). These parameters are estimated by using the Levenberg–Marquardt method coupled with the Gauss–Newton algorithm using the experimental data. The experimental data were obtained from the treatment of pretreated palm oil mill effluent (POME) as a feed in the pilot plant scale reverse osmosis system. The pretreated POME composed of a ternary system with the solutes of carbohydrate constituents, protein and ammoniacal nitrogen. The simulation results show a good agreement with the experimental data. The proposed model is suitable for predicting the performance of multiple solutes in a reverse osmosis process. The concentration of each solute present is correlated with the COD of the permeate stream. [Copyright &y& Elsevier]

Abstract: This study presents findings from an experimental investigation of the influences of several factors on the desulfurization activity of sorbents synthesized from coal fly ash, CaO, and CaSO4. Specifically, the effects of specific surface area (16.1–133.3m2/g), reaction temperature (60–300°C), feed concentration of SO2 (500–2500ppm), and feed concentration of NO (0–750ppm) were elucidated using a fixed bed reactor. In general, the sorbent desulfurization activity increased with increasing specific surface area, reaction temperature, and NO concentration but with decreasing SO2 concentration. The physical and chemical properties of sorbent before and after SO2 capture were characterized through scanning electron microscopy, X-ray diffraction, and Fourier transform infrared analyses. [Copyright &y& Elsevier]