• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.315-317
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• 2004

Henry's law constants of trichloroethylene (TCE) and tetrachloroethylene (PCE) in air-aqueous surfactant systems were determined by gas chromatography headspace analysis of closed system. The effect of surfactant type and concentration was investigated.

• Environmental Engineering Research
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• v.9 no.2
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• pp.88-95
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• 2004

• Advances in environmental research
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• v.7 no.2
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• pp.139-159
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• 2018

Green Leaf Volatiles (GLVs) is a class of biogenically emitted oxygenated hydrocarbons that have been identified as a potential source of Secondary Organic Aerosols (SOA) via aqueous oxidation. The physico-chemical properties of GLVs are vital to understanding their fate and transport in the atmosphere via fog processing, but few experimental data are available. We studied the aqueous solubility, 1-octanol/water partition coefficient, and Henry's law constant ($K_H$) of five GLVs at $25^{\circ}C$: methyl jasmonate, methyl salicylate, 2-methyl-3-buten-2-ol, cis-3-hexen-1-ol, and cis-3-hexenyl acetate. Henry's law constant was also measured at temperatures and ionic strengths typical of fog. Experimental values are compared to scarcely-available literature values, as well as estimations using group and bond contribution methods, property-specific correlations and molecular dynamics simulations. From these values, the partition coefficients to the air-water interface were also calculated. The large Henry's law constant of methyl jasmonate ($8091{\pm}1121M{\cdot}atm^{-1}$) made it the most significant GLV for aqueous phase photochemistry. The HENRYWIN program's bond contribution method from the Estimation Programs Interface Suite (EPI Suite) produced the best estimate of the Henry's constant for GLVs. Estimations of 1-octanol/water partition coefficient and solubility are best when correlating an experimental value of one to find the other. Finally, the scavenging efficiency was calculated for each GLV indicating aqueous phase processing will be most important for methyl jasmonate.

• Journal of Industrial Technology
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• v.39 no.1
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• pp.41-45
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• 2019

Hydrogen sulfide ($H_2S$) is mainly produced along with methane and hydrocarbons in many gas fields as well as hydrodesulfurization processes of crude oils containing sulfur compounds and the emission of $H_2S$ has a considerable effect on both environmental problem and human health aspects due to formation of, e.g. acid rain and smog. In recent years, ionic liquids (ILs) have been proposed as the most promising solvents for $CO_2$ and hazardous pollutants capture, such as $H_2S$ and sulfur dioxide ($SO_2$). In this work, we demonstrate the use of the predictive COSMO-SAC model for the prediction of Henry's law constant of $H_2S$ in ILs. Furthermore, the method is used to screen for potential IL candidates for $H_2S$ capture from a set of 2,624 ILs formed from 82 cations and 32 anions. The effects of cation on the Henry's law constant of $H_2S$ such as (i) the variation of the alkyl chain length on cation, (ii) the substituent of methyl group ($-CH_3$) for H in C(2) position and (iii) the change of ring structure for cation family are clearly predicted by COSMO-SAC model.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1997.06a
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• pp.87-94
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• 1997

One of the general properties of adsorption on multilayer is that the amount of adsorbing particles is not saturated. As another important property, in many cases, the amount of adsorbed particles is linearly proportional to the pressure of gases above the layers, at sufficiently low pressure, which is known to be Henry's experimental law. A purpose of this paper is to show qualitatively, in terms of a theory, that an adsorption on multilayer lbeys Henry's law at the region of low pressure. For this, we introduce a simple multilayer adsorption model and establish an adsorption isotherm for the given model, which is analyzed in the limit of low pressure.

• Bulletin of the Korean Chemical Society
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• v.30 no.8
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• pp.1749-1754
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• 2009

Solubilities of carbon dioxide (C$O_2$) in a series of fluorine-free room temperature ionic liquids (RTILs), dialkylimidazolium dialkylphosphates and dialkylimidazolium alkylphosphites, were measured at 313∼333 K and pressures up to 5 MPa. Henry’s law coefficients as the solubility parameter of C$O_2$ in RTILs were derived from the isotherm of fugacity versus C$O_2$ mole fraction. The C$O_2$ solubility in a phosphorus-containing RTIL was found to increase with the increasing molar volume of the RTIL. In general, dialkylimidazolium dialkylphosphate exhibited higher absorption capacity than dialkylimidazolium alkylphosphite as long as the RTILs possess an identical cation. Among RTILs tested, 1-butyl-3-methylimidazolium dibutylphosphate [BMIM][B$u_2PO_4$] and 1-butyl-3-methylimidazolium butylphosphite [BMIM][BuHP$O_3$] exhibited similar Henry’s law coefficients to 1-butyl-3-methylimidazolium bis (trifluoromethylsulfonyl)imide ([BMIM][T$f_2$N]) and 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][B$F_4$]), respectively. The Krichevsky-Kasarnovsky equation was employed to derive the C$O_2$ solubility parameter (Henry’s law coefficient) from the solubility data measured at elevated pressures.

• Nuclear Engineering and Technology
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• v.54 no.3
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• pp.940-947
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• 2022

Meta-heuristic algorithms have found their place in optimization problems. Henry gas solubility optimization (HGSO) is one of the newest population-based algorithms. This algorithm is inspired by Henry's law of physics. To evaluate the performance of a new algorithm, it must be used in various problems. On the other hand, the optimization of the proportional-integral-derivative (PID) gains for load-following of a nuclear power plant (NPP) is a good challenge to assess the performance of HGSO. Accordingly, the power control of a pressurized water reactor (PWR) is targeted, based on the point kinetics model with six groups of delayed-neutron precursors. In any optimization problem based on meta-heuristic algorithms, an efficient objective function is required. Therefore, the integral of the time-weighted square error (ITSE) performance index is utilized as the objective (cost) function of HGSO, which is constrained by a stability criterion in steady-state operations. A Lyapunov approach guarantees this stability. The results show that this method provides superior results compared to an empirically tuned PID controller with the least error. It also achieves good accuracy compared to an established GA-tuned PID controller.

• Journal of Environmental Science International
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• v.23 no.11
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• pp.1835-1842
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• 2014

The goal of this study was to evaluate micro-bubble concentration ($C_{air}$) in water by air/water ratio (A/W ratio) with a micro-bubble generating pump. The estimation of micro-bubble concentration is based on the balance of inlet/outlet air and water flow rate. On net A/W ratio to be generated micro-bubble, we found that the obtained the $C_{air}$ are shown as a function of discharge pressure ($P_g$) of the micro-bubble generating pump. The correlation of the $C_{air}$ and the $P_g$ ($C_{air}=3.261P_g-1.754$) was adequately described by the least square methods with a high correlation coefficient (r = 0.9459) and calculated values fit the experimental data quite well. The $C_{air}$ was lower than theoretical dissolved air concentration ($C_{aq}$) calculated by Henry's law. The $C_{air}$ for being operated the micro-bubble generating pump was 6.75 - 39.53 mL/L, however, we found that the optimum of the $C_{air}$ to generate micro-bubble was the range from 10 to 12 mL/L.

• Korean Chemical Engineering Research
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• v.51 no.2
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• pp.233-239
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• 2013

A quartz crystal microbalance (QCM) system coated with poly (isobutylene), polystyrene, and poly (methyl methacrylate) has been prepared to measure the adsorption amounts of benzene, toluene, and p-xylene at very low pressures. The resonant frequency shift of the QCM system is proportional to the increase in pressure in all experiments. The Henry's constants for all adsorbates on the polymer films are obtained from experimental data and compared with the minimum adsorption potential energies between adsorbates and the polymer films. In general, there is an explicit correlation between adsorption amount and the minimum adsorption potential energy.

• Proceedings of the Membrane Society of Korea Conference
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• 1993.10a
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• pp.13-20
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• 1993

The sorption equilibria and permeation rates for carbon dioxide in such glassy polymer membranes with high glass-transition temperature as polyimide, polyetherimide, polysulfone and polyethersulfone membranes, were measured. The sorption isotherms for these systems can be described well by the dual-mode sorption model, whereas the pressure dependences of the mean permeability coefficients are simulated better by a modified dual-mode mobility model than the conventional dual-mode mobility model in which the Henry's law and Langmuir populations execute four kinds of diffusive movement.