KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/123456789/1

Browse

Search Results

Now showing 1 - 10 of 19

Some of the metrics are blocked by your
consent settings
Synergistic effect of arsenic removal from petroleum condensate via liquid-liquid extraction: Thermodynamics, kinetics, DFT and McCabe-Thiele method
(2023-12-01)
Purktimatanont, Kittamuk
;
Mohdee, Vanee
;
Pancharoen, Ura
;
Maneeintr, Kreangkrai
;
Punyain, Wikorn
This work presents the purification of petroleum condensate by removing arsenic ions via liquid-liquid extraction (LLE). Influence of pure and synergistic extractants is investigated. In terms of the practicability, following parameters are examined: the type of extractant, operating time, and temperature. Response surface methodology is used to design parameters such as organic-aqueous ratio and extractant concentration. Under optimal conditions; a mixture of 1 mol/L HCl and 0.02 mol/L thiourea with an organic/aqueous ratio of 1:4 at 323.15 K for 60 min, the extraction of arsenic reached 78.2 %. Further, batch simulation via two-stage counter-current extraction, and estimation by McCabe-Thiele diagram proved to be enhanced arsenic extraction to 95.3 %. Analysis by FTIR show that arsenic ions in petroleum condensate are formed as triphenylarsine compound ((C<inf>6</inf>H<inf>5</inf>)<inf>3</inf>As). The process of arsenic removal proved to be zero-order endothermic, irreversible and spontaneous reaction. The results obtained from the density functional theory (DFT) confirm that arsenic ions react with the synergistic extractant: effectively forming a covalent bond (As–S).
Some of the metrics are blocked by your
consent settings
New upstream solution for mercury removal from petroleum condensate via HFMC: Thermodynamics, kinetics, DFT and mass transport
(2023-08-01)
Poolkaew, Waranya
;
Mohdee, Vanee
;
Purktimatanont, Kittamuk
;
Pancharoen, Ura
;
Punyain, Wikorn
This work presents a new solution for the removal of mercury from petroleum condensate via hollow fiber membrane contactor (HFMC), which follows the principles and practices of solvent extraction. Results demonstrate that mercury can be successfully removed from petroleum condensate feed by the synergistic mixture solution of HCl and thiourea as extractant. Under equal circulating flow rates of 1.67 cm3 s−1 of feed and the synergistic extractant (0.5 mol dm−3 HCl and 1.5 mol dm−3 thiourea) at 323.15 K, the percentage of mercury removal reached 98.4%. The values of ∆H° (120 kJ mol−1), ∆S° (0.37 kJ mol−1) and ∆G° (−1.15 kJ mol−1) indicate that the reaction is endothermic, irreversible and spontaneous at 323.15 K, respectively. The results of Fourier-transform infrared spectroscopy (FTIR) confirm that mercury has been removed and is consistent with the obtained reaction mechanism from density functional theory (DFT). To describe the mass transport through HFMC, two mass transport mathematical models corresponding to reaction flux and diffusion flux are considered. The reaction flux model is seen to fit in well with the experimental results. The mass transfer coefficients in the membrane phase (k<inf>m</inf>) and shell side (k<inf>s</inf>) are 7.45 × 10−6 cm s−1 and 2.09 × 10−5 cm s−1, respectively indicating that the mass transfer in the membrane phase is the controlling step.
Some of the metrics are blocked by your
consent settings
Mechanisms of mercury ions separation by non-toxic organic liquid membrane via DFT, thermodynamics, kinetics and mass transfer model
(2023-01-25)
Traiwongsa, Natthapol
;
Suren, Sira
;
Pancharoen, Ura
;
Nootong, Kasidit
;
Maneeintr, Kreangkrai
This work focuses on the separation of mercury ions from synthetic produced wastewater via hollow fiber supported liquid membrane (HFSLM). Standard sunflower oil is used as a non-toxic extractant and solvent for mercury ions separation from wastewater. Under optimal conditions: 20 ppm NaCl in wastewater, 0.1 M thiourea in 0.5 M HCl as stripping solution, flow rates of feed and stripping solutions of 100 mL/min, and temperature 323 K, percentages of extraction and stripping reach 98% and 81%, respectively. The mechanisms of extraction and stripping reactions were investigated via the density functional theory (DFT). For the extraction, a linoleic acid extracted HgCl<inf>2</inf> and formed halogen bond. For the stripping, two protonated thiourea stripped HgCl<inf>2</inf> and formed covalent and halogen bonds. According to the thermodynamics study, extraction reaction is found to be endothermic (ΔH<inf>Ex</inf>0 = 1,001.00 J/mol), irreversible (ΔS<inf>Ex</inf>0 = 3.45 J/mol K), and spontaneous, (ΔG<inf>Ex@323K</inf>0 = −112.65 J/mol). Finally, the mathematical model including conservation, convection, diffusion, reaction, and accumulation was developed. The differences of mercury ions concentration in feed and stripping phases from the experiments and the predicted data from the mathematical model were 5% and 2%, respectively indicating that the model is acceptable.
Some of the metrics are blocked by your
consent settings
Separation of platinum(IV) across hollow fiber supported liquid membrane using non-toxic diluents: Mass transfer and thermodynamics
(2017-10-25)
Wongkaew, Krirkratthawit
;
Mohdee, Vanee
;
Pancharoen, Ura
;
Arpornwichanop, Amornchai
;
Lothongkum, Anchaleeporn W.
Non-toxic diluents were studied and compared with toxic diluents for separation of platinum(IV) across hollow fiber supported liquid membrane. 91.41% extraction and 81% stripping of platinum(IV) was observed for sunflower oils at 328.15 K. Overall mass transfer resistance (R) was 146.612 × 104 s/cm. The separation process was exothermic (ΔH<inf>ex</inf> 0 = −975.20 kJ/mol) and spontaneous (ΔG<inf>ex</inf> 0 = −326.447 J/mol). The E<inf>a</inf> of 1.673 kJ/mol indicated that the diffusion of complex species across the liquid membrane controlled the mass transfer step. Moreover, a modified Apelblat model gave an excellent match for predicting the extraction behavior of platinum(IV) at 1.2818% RMSD.
Some of the metrics are blocked by your
consent settings
Mass transfer resistance and response surface methodology for separation of platinum (IV) across hollow fiber supported liquid membrane
(2016-10-25)
Wongkaew, Krirkratthawit
;
Wannachod, Thanaporn
;
Mohdee, Vanee
;
Pancharoen, Ura
;
Arpornwichanop, Amornchai
The separation of platinum (IV) from wastewater across hollow fiber supported liquid membrane was successful in reaching 96% extraction and 88% stripping using 10% (v/v) trioctylmethyl-ammonium chloride (Aliquat 336) as the extractant. The mass transfer resistances were (1/k<inf>a</inf>) 3.297 × 104 s/cm, (1/k<inf>m</inf>) 0.164 × 104 s/cm, (1/k<inf>o</inf>) 3.404 × 104 s/cm and (1/K) 6.865 × 104 s/cm. The system was governed by the mass transfer resistance from the liquid-membrane. Response surface methodology was used to qualify and estimate the influence of operating conditions. Predicted model with experimental data were in good agreement at a standard deviation of 1%.
Some of the metrics are blocked by your
consent settings
Antibacterial activity and nanocomposite properties of monodispersed silver nanoparticles synthesized by the microwave method
(2016-01-01)
Lothongkum, Anchaleeporn W.
;
Wongparb, Kornwika
;
Sethapokin, Pinthep
;
Chaisitsak, Sutichai
Monodispersed colloidal silver nanoparticles (Ag-NPs) were synthesized by a simple and rapid microwave method. A precursor, AgNO<inf>3</inf>, was reduced by ethylene glycol (EG) and N,N-dimethylformamide (DMF) in the presence of polyvinylpyrrolidone (PVP) as a stabilizer or capping agent. It was found that the concentration of AgNO<inf>3</inf> significantly affected Ag-NPs particle sizes. The particle sizes decreased when the concentration decreased from 0.1 to 0.05 and 0.01 M, which corresponded to narrow size distribution of the particle diameters of approximately 60 to 80, 30 to 40 and 10 to 20 nm. The spherical-shaped monodispersed Ag-NPs were obtained by using a volume ratio of EG to DMF of 2.75:2.25, microwave power of 400 W and heating time of 2 min. The volume ratio of EG to DMF and the microwave power influenced the uniformity of the Ag-NPs shape and size, while the heating time had no effect. For antibacterial application, 60-80 and 10-20 nm Ag-NPs showed good disinfection ability against Escherichia coli (ATCC 25922) at the minimum inhibitory concentrations (MIC) of 32 and 16 (μg × ml-1, respectively. In addition, the electrical resistance of the nanocomposites of DMF-loaded Ag-NPs (20-50 nm) without PVP on single-walled carbon nanotubes and polyethylene terephthalate (PET) was measured. As a result, it is obvious that the Ag-NPs help to increase the electrical conductivity of the nanocomposites as the electrical resistance of the Ag-NPs nanocomposites was 4.68 kΩ × cm-2 compared to that of the nanocomposites without Ag-NPs of 8.76 kΩ × cm-2.
Some of the metrics are blocked by your
consent settings
Effect of diluent polarity on membrane stability in the separation of trace Pd(II) from wastewater by HFSLM using LIX84-I
(2015-01-25)
Wongkaew, Kraiwith
;
Pancharoen, Ura
;
Phatanasri, Suphot
;
Leepipatpiboon, Natchanun
;
Lothongkum, Anchaleeporn W.
In a liquid membrane, the type of diluents for the selected extractant plays an important role in membrane stability and separation efficiency. High Pd(II) extraction and stripping of 96% and 91%, respectively, were observed by HFSLM under a feed pH 2, 5% (v/v) LIX84-I dissolved in kerosene and a mixture of 0.8M NH<inf>2</inf>CSNH<inf>2</inf> with 1M HCl as a stripping solution. The highest stability was attained at 350min by using hexane as a diluent. Finally, the calculated activation energy (E<inf>a</inf>) of 30 kJ/mol implied that the separation of Pd(II) was controlled by the diffusion and chemical reaction.
Some of the metrics are blocked by your
consent settings
Arsenic removal from natural gas condensate using a pulsed sieve plate column and mass transfer efficiency
(2012-02-01)
Chaturabul, Srestha
;
Wannachod, Pharannalak
;
Rojanasiraprapa, Bongkotch
;
Summakasipong, Supat
;
Lothongkum, Anchaleeporn W.
This work applied a pulsed sieve plate column in conjunction with liquid-liquid extraction technique to remove arsenic from natural gas condensate. The relevant parameters, that is the type and concentration of the extractant, pulse velocity, volumetric-flow rate ratio of the condensate to the extractant, operating time, and extraction cycle were investigated. Mass transfer efficiency in terms of the overall height of transfer unit (HTU <inf>oy</inf>cm) and the interfacial area (m 2/m 3) were calculated. The highest percentage of arsenic removal in this study was 94% corresponding to the calculated HTU <inf>oy</inf> of 26 cm and the calculated interfacial area of 118 m 2/m 3 at the optimum conditions: the mixture of the extractant (1 M hydrochloric acid and 20% (v/v) methanol), pulse velocity of 20 mm/s, and volumetric-flow rate ratio of the condensate to the extractant of 1:4. By using continuous operation in the cycle mode, the percentages of arsenic removal were observed at 94, 85, and 80 from the respective 1st, 2nd, and 3rd cycles. The operation was based on the condition that fresh feed was introduced in each cycle while the extractant was reused. © Taylor and Francis Group, LLC.
Some of the metrics are blocked by your
consent settings
A reaction flux model for extraction of Cu(ii) with LIX84i in HFSLM
(2011-09-01)
Pancharoen, Ura
;
Wongsawa, Thidarut
;
Lothongkum, Anchaleeporn W.
Hollow fiber supported liquid membrane (HFSLM) is a favorable method to extract both valuable compounds and heavy metal pollutants such as chromium, copper, and nickel at a very low concentration. In this work, the extraction of Cu(II) by LIX84I dissolved in kerosene was theoretically and experimentally investigated. A model to estimate the percentage of extraction of copper ions from synthetic water considering the effect of reaction flux in membrane phase of the HFSLM system was studied. H<inf>2</inf>SO<inf>4</inf> solution was used as the stripping solution. The facilitated transport mechanism of the chemical reaction at the feed-membrane interface was taken into account in the model equations. The percentage of copper ion extraction was plotted against its initial concentration in feed and also feed flow rate. Subsequently, the separation time and separation cycle were determined in accordance with the simulated values of copper ion concentration and the feed flow rate from the model. The modeled results were in good agreement with the experimental data at the average percentage of deviation about 2%. © Taylor & Francis Group, LLC.
Some of the metrics are blocked by your
consent settings
Application of the AERMOD modeling system for environmental impact assessment of NO 2 emissions from a cement complex
(2011-06-01)
Seangkiatiyuth, Kanyanee
;
Surapipith, Vanisa
;
Tantrakarnapa, Kraichat
;
Lothongkum, Anchaleeporn W.
We applied the model of American Meteorological Society-Environmental Protection Agency Regulatory Model (AERMOD) as a tool for the analysis of nitrogen dioxide (NO <inf>2</inf>) emissions from a cement complex as a part of the environmental impact assessment. The dispersion of NO <inf>2</inf> from four cement plants within the selected cement complex were investigated both by measurement and AERMOD simulation in dry and wet seasons. Simulated values of NO <inf>2</inf> emissions were compared with those obtained during a 7-day continuous measurement campaign at 12 receptors. It was predicted that NO <inf>2</inf> concentration peaks were found more within 1 to 5 km, where the measurement and simulation were in good agreement, than at the receptors 5 km further away from the reference point. The Quantile-Quantile plots of NO <inf>2</inf> concentrations in dry season were mostly fitted to the middle line compared to those in wet season. This can be attributed to high NO <inf>2</inf> wet deposition. The results show that for both the measurement and the simulation using the AERMOD, NO <inf>2</inf> concentrations do not exceed the NO <inf>2</inf> concentration limit set by the National Ambient Air Quality Standards (NAAQS) of Thailand. This indicates that NO <inf>2</inf> emissions from the cement complex have no significant impact on nearby communities. It can be concluded that the AERMOD can provide useful information to identify high pollution impact areas for the El A guidelines. © 2011 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences.

KMITL

Browse

Filters

Settings

Sort By

Results per page

Search Results