Abstract: The epoxidation of soybean oil at temperature of 600C
was provided the best result in terms of attaching the –OH
functionality. Temperatures below and above 600C it is likely the
attaching reaction did not proceed sufficiently fast. The considerable
yield below 40%, implies the oil is not completely converted, it is not
possible by conventional methods, because the epoxide decomposes
at the temperature required. The objective of this work was the
development of catalyst toward the conversion of epoxide and polyol
with reaction temperature at 50,60, and 700C. The effect of different
type of catalyst were studied, the effect of alcohols with different
molecular configuration was determined which leads to selective
addition of alcohols to the epoxide oils.
Abstract: The aim of this study is to compare the effect of the ultrasonic pre treatment on the removal of heavy metals (Iron, Zinc and Copper) from Acid Mine Drainage (AMD) by Denver Cell flotation. Synthetic AMD and individual metal solutions are used in the initial experiments to optimise the process conditions for real AMD. Three different process methods, ultrasound treatment followed by Denver flotation cell, Denver flotation cell alone and ultrasonic treatments run simultaneously with the Denver flotation cell were tested for every sample. Precipitation of the metal solutions by using sodium hydroxide (NaOH) and application of the optimum frother dosage followed by flotation significantly reduced the metal content of the AMD.
Abstract: In composting process, N high-organic wastes loss the
great part of its nitrogen as ammonia; therefore, using compost
amendments can promote the quality of compost due to the decrease
in ammonia volatilization. With regard to the effect of pH on
composting, microorganisms- activity and ammonia volatilization,
sulfuric acid and alkaline wastewater of paper mill (as liming agent
with Ca and Mg ions) were used as compost amendments. Study
results indicated that these amendments are suitable for reclamation
of compost quality properties. These held nitrogen in compost caused
to reduce C/N ratio. Both amendments had a significant effect on
total nitrogen, but it should be used sulfuric acid in fewer amounts
(20 ml/kg fresh organic wastes); and the more amounts of acid is not
proposed.
Abstract: Air emissions from waste treatment plants often
consist of a combination of Volatile Organic Compounds (VOCs)
and odors. Hydrogen sulfide is one of the major odorous gases
present in the waste emissions coming from municipal wastewater
treatment facilities. Hydrogen sulfide (H2S) is odorous, highly toxic
and flammable. Exposure to lower concentrations can result in eye
irritation, a sore throat and cough, shortness of breath, and fluid in
the lungs. Biofiltration has become a widely accepted technology for
treating air streams containing H2S. When compared with other nonbiological
technologies, biofilter is more cost-effective for treating large
volumes of air containing low concentrations of biodegradable compounds.
Optimization of biofilter media is essential for many reasons such as:
providing a higher surface area for biofilm growth, low pressure drop,
physical stability, and good moisture retention. In this work, a novel
biofilter media is developed and tested at a pumping station of a
municipality located in the United Arab Emirates (UAE). The
media is found to be very effective (>99%) in removing H2S
concentrations that are expected in pumping stations under steady
state and shock loading conditions.
Abstract: A double module hollow fiber supported liquid
membrane (HFSLM) was applied to selectively separate lead and
mercury ions from dilute synthetic produced water. The experiments
were investigated on several variables: types of extractants
(D2EHPA, Cyanex 471, Aliquat 336, and TOA), concentration of the
selected extractant and operating time. The results clearly showed
that the double module HFSLM could selectively separate Pb(II) and
Hg(II) in feed solution at a very low concentration to less than the
regulatory discharge limit of 0.2 and 0.005 mg/L issued by the
Ministry of Industry and the Ministry of Natural Resource
Environment, Thailand. The highest extractions of lead and mercury
ions from synthetic produced water were 96% and 100% using 0.03
M D2EHPA and 0.06 M Aliquat 336 as the extractant for the first
and second modules.
Abstract: Coal fly ash (CFA) generated by coal-based thermal
power plants is mainly composed of quartz, mullite, and unburned
carbon. In this study, the effect of unburned carbon on CFA toward
its adsorption capacity was investigated. CFA with various carbon
content was obtained by refluxing it with sulfuric acid having various
concentration at various temperature and reflux time, by heating at
400-800°C, and by sieving into 100-mesh in particle size. To
evaluate the effect of unburned carbon on CFA toward its adsorption
capacity, adsorption of methyl violet solution with treated CFA was
carried out. The research shows that unburned carbon leads to
adsorption capacity decrease. The highest adsorption capacity of
treated CFA was found 5.73 x 10-4mol.g-1.
Abstract: The traditional method for essential oil extraction from agarwood (Aquilaria Crassna) is to soak it in water and follow with hydrodistillation. The effect of various agarwood pretreatments: ethanol, acid, alkaline, enzymes, and ultrasound, and the effect of subcritical water extraction(SWE) was studied to compare with the traditional method. The major compositions of agarwood oil from hydrodistillation were aroma compounds as follow: aristol-9-en-8- one (21.53%), selina-3, 7(11)-diene (12.96%), τ-himachalene (9.28%), β-guaiene (5.79%), hexadecanoic acid (4.90%) and guaia- 3,9-diene (4.21%). Whereas agarwood oil from pretreatments with ethanol and ultrasound, and SWE got fatty acid compounds. Extraction of agarwood oil using these pretreatments could improve the agarwood oil yields up to 2 times that of the traditional method. The components of the pretreated sample with diluted acid (H2SO4) at pH 4 gave quite similar results as the traditional method. Therefore, the enhancement of essential oil from agarwood depends on requirement of type of extracted oil that involved extraction methods.
Abstract: Based on a global kinetics of direct dimethyl ether (DME) synthesis process from syngas, a steady-state one-dimensional mathematical model for the bubble column slurry reactor (BCSR) has been established. It was built on the assumption of plug flow of gas phase, sedimentation-dispersion model of catalyst grains and isothermal chamber regardless of reaction heats and rates for the design of an industrial scale bubble column slurry reactor. The simulation results indicate that higher pressure and lower temperature were favorable to the increase of CO conversion, DME selectivity, products yield and the height of slurry bed, which has a coincidence with the characteristic of DME synthesis reaction system, and that the height of slurry bed is lessen with the increasing of operation temperature in the range of 220-260℃. CO conversion, the optimal operation conditions in BCSR were proposed.
Abstract: Owing to the stringent environmental legislations,
CO2 capture and sequestration is one of the viable solutions to reduce
the CO2 emissions from various sources. In this context, Ionic liquids
(ILs) are being investigated as suitable absorption media for CO2
capture. Due to their non-evaporative, non-toxic, and non-corrosive
nature, these ILs have the potential to replace the existing solvents
like aqueous amine solutions for CO2 separation technologies. Thus,
the present work aims at studying the important aspects such as the
interactions of CO2 molecule with different anions (F-, Br-, Cl-, NO3
-,
BF4
-, PF6
-, Tf2N-, and CF3SO3
-) that are commonly used in ILs
through molecular modeling. In this, the minimum energy structures
have been obtained using Ab initio based calculations at MP2
(Moller-Plesset perturbation) level. Results revealed various degrees
of distortion of CO2 molecule (from its linearity) with the anions
studied, most likely due to the Lewis acid-base interactions between
CO2 and anion. Furthermore, binding energies for the anion-CO2
complexes were also calculated. The implication of anion-CO2
interactions to the solubility of CO2 in ionic liquids is also discussed.
Abstract: A rigorous two-dimensional model is developed for simulating the operation of a less-investigated type steam reformer having a considerably lower operating Reynolds number, higher tube diameter, and non-availability of extra steam in the feed compared with conventional steam reformers. Simulation results show that reasonable predictions can only be achieved when certain correlations for wall to fluid heat transfer equations are applied. Due to severe operating conditions, in all cases, strong radial temperature gradients inside the reformer tubes have been found. Furthermore, the results show how a certain catalyst loading profile will affect the operation of the reformer.
Abstract: A new chelating resin is prepared by coupling
Amberlite XAD-4 with 1-amino-2-naphthole through an azo spacer.
The resulting sorbent has been characterized by FT-IR, elemental
analysis and thermogravimetric analysis (TGA) and studied for
preconcentrating of Cu (II) using flame atomic absorption
spectrometry (FAAS) for metal monitoring. The optimum pH value
for sorption of the copper ions was 6.5. The resin was subjected to
evaluation through batch binding of mentioned metal ion.
Quantitative desorption occurs instantaneously with 0.5 M HNO3.
The sorption capacity was found 4.8 mmol.g-1 of resin for Cu (II) in
the aqueous solution. The chelating resin can be reused for 10 cycles
of sorption-desorption without any significant change in sorption
capacity. A recovery of 99% was obtained the metal ions with 0.5 M
HNO3 as eluting agent. The method was applied for metal ions
determination from industrial waste water sample.
Abstract: This study investigates the capacity of granular
activated carbon (GAC) for the storage of methane through the
equilibrium adsorption. An experimental apparatus consist of a dual
adsorption vessel was set up for the measurement of equilibrium
adsorption of methane on GAC using volumetric technique (pressure
decay). Experimental isotherms of methane adsorption were
determined by the measurement of equilibrium uptake of methane in
different pressures (0-50 bar) and temperatures (285.15-328.15°K).
The experimental data was fitted to Freundlich and Langmuir
equations to determine the model isotherm. The results show that the
experimental data is equally well fitted by the both model isotherms.
Using the experimental data obtained in different temperatures the
isosteric heat of methane adsorption was also calculated by the
Clausius-Clapeyron equation from the Sips isotherm model. Results
of isosteric heat of adsorption show that decreasing temperature or
increasing methane uptake by GAC decrease the isosteric heat of
methane adsorption.
Abstract: Methanol-to-olefins coupled with transformation of
coal or natural gas to methanol gives an interesting and promising way
to produce ethylene and propylene. To investigate solid concentration
in gas-solid fluidized bed for methanol-to-olefins process catalyzed by
SAPO-34, a cold model experiment system is established in this paper.
The system comprises a gas distributor in a 300mm internal diameter
and 5000mm height acrylic column, the fiber optic probe system and
series of cyclones. The experiments are carried out at ambient
conditions and under different superficial gas velocity ranging from
0.3930m/s to 0.7860m/s and different initial bed height ranging from
600mm to 1200mm. The effects of radial distance, axial distance,
superficial gas velocity, initial bed height on solid concentration in the
bed are discussed. The effects of distributor shape and porosity on
solid concentration are also discussed. The time-averaged solid
concentration profiles under different conditions are obtained.
Abstract: The mechanical properties of blends consisting of
plasticized poly(vinyl butyral) (PVB) and plasticized poly(vinyl
chloride) (PVC) are studied, in order to evaluate the possibility of
using recycled PVB waste derived from windshields. PVC was
plasticized with 38% of diisononyl phthalate (DINP), while PVB was
plasticized with 28% of triethylene glycol, bis(2-ethylhexanoate)
(3GO). The optimal process conditions for the PVB/PVC blend in 1:1
ratio were determined. Entropy was used in order to theoretically
predict the blends miscibility. The PVB content of each blend
composition used was ranging from zero to 100%. Tensile strength
and strain were tested. In addition, a comparison between recycled
and original PVB, used as constituents of the blend, was performed.
Abstract: The paper provides biomasses characteristics by
proximate analysis (volatile matter, fixed carbon and ash) and
ultimate analysis (carbon, hydrogen, nitrogen and oxygen) for the
prediction of the heating value equations. The heating value
estimation of various biomasses can be used as an energy evaluation.
Thirteen types of biomass were studied. Proximate analysis was
investigated by mass loss method and infrared moisture analyzer.
Ultimate analysis was analyzed by CHNO analyzer. The heating
values varied from 15 to 22.4MJ kg-1. Correlations of the calculated
heating value with proximate and ultimate analyses were undertaken
using multiple regression analysis and summarized into three and two
equations, respectively. Correlations based on proximate analysis
illustrated that deviation of calculated heating values from
experimental heating values was higher than the correlations based
on ultimate analysis.
Abstract: Residual dye contents in textile dyeing wastewater have complex aromatic structures that are resistant to degrade in biological wastewater treatment. The objectives of this study were to determine the effectiveness of nanoscale zerovalent iron (NZVI) to decolorize Reactive Black 5 (RB5) and Reactive Red 198 (RR198) in synthesized wastewater and to investigate the effects of the iron particle size, iron dosage and solution pHs on the destruction of RB5 and RR198. Synthesized NZVI was confirmed by transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The removal kinetic rates (kobs) of RB5 (0.0109 min-1) and RR198 (0.0111 min-1) by 0.5% NZVI were many times higher than those of microscale zerovalent iron (ZVI) (0.0007 min-1 and 0.0008 min-1, respectively). The iron dosage increment exponentially increased the removal efficiencies of both RB5 and RR198. Additionally, lowering pH from 9 to 5 increased the decolorization kinetic rates of both RB5 and RR198 by NZVI. The destruction of azo bond (N=N) in the chromophore of both reactive dyes led to decolorization of dye solutions.
Abstract: This work aims to test the application of computational fluid dynamics (CFD) modeling to fixed bed catalytic cracking reactors. Studies of CFD with a fixed bed design commonly use a regular packing with N=2 to define bed geometry. CFD allows us to obtain a more accurate view of the fluid flow and heat transfer mechanisms present in fixed bed equipment. Naphtha was used as feedstock and the reactor length was 80cm. It is divided in three sections that catalyst bed packed in the middle section of the reactor. The reaction scheme was involved one primary reaction and 24 secondary reactions. Because of high CPU times in these simulations, parallel processing have been used. In this study the coke formation process in fixed bed and empty tube reactor was simulated and coke in these reactors are compared. In addition, the effect of steam ratio and feed flow rate on coke formation was investigated.
Abstract: This paper focuses on the experimental impacts of
ultrasonic, carbonate and a combination of them on the quality of
fresh kiwi juice. Today, non-thermal methods like ultrasonic, which
have imperceptible effects on some properties of the juice such as
taste, flavor and color, are commonly used for killing
microorganisms.In this paper, some properties of kiwi fruit juice
under ultrasonic, carbonate and a combination of them has been
researched. Those properties include pH, acidity, transparency and
Brix. Its impact on microorganisms has been studied as well.The
results show that using a combination of carbonate and sonicate make
the cavitation more severe without a perceptible effect on nonactivation
of microorganisms.
Abstract: In the last decades, the problem of perforation
damage has been considered as the major factor for the
reduction of oil productivity. Underbalance perforation is
considered as one of the best means to minimize or overcome
this problem. By maintaining wellbore pressure lower than
formation pressure, perforation damage could be minimize or
eliminated. This can be achieved by the use of nontraditional
lightweight completion fluid. This paper presents the effect of
natural clay in formulating nontraditional completion fluid to
ensure successful perforation job and increase of production
rate. Natural clay is used as homogenizing agent to create a
stable and non-damaging low-density completion fluid.
Results indicate that the addition of natural clay dramatically
increase the stability of the final fluids. In addition, field test
has shown that the application of nontraditional completion
fluid increases oil production by three folds.
Abstract: In this study, solid phase micro-extraction (SPME)
was optimized to improve the sensitivity and accuracy in
formaldehyde determination for plywood panels. Further work has
been carried out to compare the newly developed technique with
existing method which reacts formaldehyde collected in desiccators
with acetyl acetone reagent (DC-AA). In SPME, formaldehyde was
first derivatized with O-(2,3,4,5,6 pentafluorobenzyl)-hydroxylamine
hydrochloride (PFBHA) and analysis was then performed by gas
chromatography in combination with mass spectrometry (GC-MS).
SPME data subjected to various wood species gave satisfactory
results, with relative standard deviations (RSDs) obtained in the
range of 3.1-10.3%. It was also well correlated with DC values,
giving a correlation coefficient, RSQ, of 0.959. The quantitative
analysis of formaldehyde by SPME was an alternative in wood
industry with great potential