• Journal of the Korean Chemical Society
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• v.14 no.1
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• pp.85-89
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• 1970

The rate of the bromine-exchange reaction between gallium bromide and isopropyl bromide in nitrobenzene was measured at 19$^{\circ},\;25^{\circ}$ and 40$^{\circ}C$., using isopropyl bromide labelled with Br-82. The results indicated that the exchange reaction was second order with respect to gallium bromide and first order with respect to isopropyl bromide. The third-order rate constant determined at 19$^{\circ}C$. was 3.2 ${\times}10^{-2}l^2{\cdot}mole^{-2}sec^{-1}$. The activation energy, the enthalpy of activation and the entropy of activation for the exchange reaction were also determined.

• Journal of the Korean Chemical Society
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• v.24 no.4
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• pp.302-309
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• 1980

The solubilities of n-propyl bromide in nitrobenzene and in 1,2,4-trichlorobenzene have been measured at 19, 25 and $40^{\circ}C$ in the presence and absence of gallium bromide. When gallium bromide does not exist in the system, the solubility of n-propyl bromide in nitrobenzene is greater than in 1,2,4-trichlorobenzene, indicating a stronger interaction of n-propyl bromide with nitrobenzene than with 1,2,4-trichlorobenzene. In the presence of gallium bromide, 1: 1 complex $n-C_3H_7Br\cdotGaBr_3$ is formed in the solution. The instability constant K of the complex was evaluated. $$n-C_3H_7Br\cdotGaBr_3 \rightleftarrows n-C_3H_7Br ＋ \frac{1}{2Ga_2Br_6 }$$The change of enthalpy, free energy and entropy for the dissociation of the complex were also calculated. It seems that the stabilities of the complex, gallium bromide with alkyl bromide, are relatively concerned with the stabilities of the alkyl ion.

• Journal of the Korean Chemical Society
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• v.38 no.3
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• pp.208-213
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• 1994

The solubility of i-butyl bromide in nitrobenzene have been measured at 19, 25 and $40^{\circ}C$ in the presence and absence of gallium bromide. In the presence of gallium bromide, 1 : 1 complex, $i-C_4H_9Br{\cdot}GaBr_3$ is formed in the solution. The instability constant K of the complex formation was evaluated from the following equilibrium equation. $i-C_4H_9Br{\cdot}GaBr_3{\rightleftharpoons}C_4H_9Br + 1/2Ga_2Br_6.$ From these result, it seems that the stabilities of the complex formation, gallium bromide with alkyl bromide, are directly related with those of the carbonium ions of alkyl bromide.

• Journal of the Korean Chemical Society
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• v.20 no.6
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• pp.479-485
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• 1976

The rate of the bromine-exchange reaction between gallium bromide and n-butyl bromide in 1,2,4-trichlorobenzene and in nitrobenzene was measured at 19, 25 and 40$^{\circ}C$., using n-butyl bromide labelled with Br-82. The results indicated that the exchange reaction was second order with respect to gallium bromide and first order with respect to n-butyl bromide. The third-order rate constant determined at $19^{\circ}C.$ is 1.15{\times}10^{-4} l^2{\cdot}mole^{-2}{\cdot}sec^{-1}$ in 1,2,4-trichlorobenzene and $4.21{\times}10^{-4} l^2·$$mole^{-2}{\cdot}sec^{-1}$ in nitrobenzene. The activation energy, the enthalpy of activation and the entropy of activation for the exchange reaction were also determined.

• Journal of the Korean Chemical Society
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• v.29 no.1
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• pp.9-14
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• 1985

The solubilities of i-propyl bromide in nitrobenzene have been measured at 10$^{\circ}$, 19$^{\circ}$ and 25$^{\circ}C$ in the presence and absence of gallium bromide. In the presence of gallium bromide, 1 : 1 complex, i-C$_3$H$_7Br{\cdot}GaBr_3$ is formed in the solution. The instability constant K of the complex formation was evaluated from the following equilibrium equation: i-C$_3$H$_7Br{\cdot}GaBr_3$ ${\rightleftharpoons}$ i-C$_3$H$_7$Br + $\frac{1}{2}$$Ga_2Br_6$. The change of enthalpy, free energy and entropy for the dissociation of the complex were also calculated. From these result, it seems that the stabilities of the complex formation, gallium bromide with alkyl bromide, are directly related with those of the carbonium ions of alkyl bromide.

• Journal of the Korean Chemical Society
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• v.35 no.5
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• pp.480-486
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• 1991

The solubilities of ethyl bromide in aniline and o-chloroaniline have been measured at 5, 15$^{\circ}$ and 25$^{\circ}$C in the presence and the absence of gallium bromide. When gallium bromide does not exist in the system, the solubility of ethyl bromide in o-chloroaniline is greater than in aniline, indicating a stronger interaction of ethyl bromide with o-chloroaniline than that with aniline. It could be thought that ethyl bromide forms unstable complex with gallium bromide in the presence of gallium bromide in the system. This complex has been assumed in various ways and evaluated, that instability constant (K value) is relatively constancy under the assumption of 1 : 1 complex, $C_2H_5Br{\cdot}GaBr_3$. Therefore, the complex forms the following equilibrium in the solution: $C_2H_5Br{\cdot}GaBr_3\;{\rightleftharpoons}\;C_2H_5Br +1/2Ga_2Br_6$ The instability of the complex of ethyl bromide with gallium bromide is compared with similar complexes of gallium bromide with methyl bromide. The changes of enthalpy, free energy and entropy fcor the dissociation of the complex are also calculated.

• Journal of the Korean Chemical Society
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• v.15 no.5
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• pp.228-235
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• 1971

The solubilities of n-butyl bromide in nitrobenzene and in 1,2,4-trichlorobenzene have been measured at $19^{\circ},\;25^{\circ},\;and\;40^{\circ}C$ in the presence and absence of gallium bromide. When gallium bromide does not exist in the system, the solubility of n-butyl bromide in nitrobenzene is greater than in 1,2,4-trichlorobenzene, indicating a stronger interaction of n-butyl bromide with nitrobenzene than with 1,2,4-trichlorobenzene. In the presence of gallium bromide, complex of n-butyl bromide with gallium bromide, 1:1 complex, $n-C_4H_9Br{\cdot}GaBr_3$, is formed in the solution. The instability constant K of the complex was evaluated. $n-C_4H_9Br{\cdot}GaBr_3{\rightleftharpoons}n-C_4H_9Br+\frac{1}{2}Ga_2Br_6$ The changes of enthalpy, free energy and entropy for the dissociation of the complex were also calculated.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.2
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• pp.178-182
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• 2006

The purpose of this research is to remove the bromate that is a disinfection by-poduct of water purification by ozone. I achieved a high rate of removal with iron, copper, or silver impregnated activated carbon by using both the adsorbing power of granular activated carbon and the oxidizing power of metal ions as deoxidizing agents. In the removal test of bromate with the quantity of activated carbon input I injected each activated carbon by 0.1, 0.3, 0.1, and 1.0 g and let them react for 240 minutes. I found the quantity of removed bromate was in proportion to the amount of input. The removal rate of bromate increased about 20% when I used acid treated activated carbon. The metal impregnated activated carbon had a higher removal rate of bromate than that of general activated carbon by about $30{\sim}50%$. Iron impregnated activated carbon showed a 92% removal rate of bromate. Iron, copper, or silver impregnated activated carbon removed about $0.9{\sim}1.5mg\;{BrO_3}^-/g$ while general activated carbon removed about $0.02{\sim}0.45mg\;{BrO_3}^-/g$. In the continuous column reaction, there were breakthrough phenomena at 96, 180, and 252 hours when I tested EBCT by 1, 2 and 3 minutes while I was changing the flux rate of bromate from 15.6 to 46.8 mL/min.

• Analytical Science and Technology
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• v.11 no.2
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• pp.88-91
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• 1998

Bromide($Br^-$) was separated and quantified with $2.8mM-NaHCO_3/2.2mM-Na_2CO_3$ by Ion Chromatography. Bromide was eluted at 8.9 min. and the detectetion limit was 2.5 ng. We compared with bromide concentration in normal or methylbromide intoxicated bloods and tissues. Bromide concentrations were 2.0~5.8 ppm in normal bloods and 1.0~5.3 ppm in normal tissues. In fatal cases of methylbromide intoxication, blood bromide concentrations (4 cases) of 74.2~139 ppm and tissue bromide concentration (1 case) of 76 (heart)~201 (lung) ppm were detected. In fatal cases, blood bromide concentrations. were 12~22 times higher than those of normal bloods.

• Polymer(Korea)
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• v.33 no.5
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• pp.509-513
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• 2009

For examining an effect of lithium bromide on structure and property of chitosan/fibroin blend, we investigated the structural characteristic of chitosan/fibroin blend films using solution with lithium bromide which was removed during a casting. The chitosan/fibroin blend formed a complex with the dissolved bromine/lithium ions. The crystalline phase of the complex was found in the blend film at LiBr concentration of 0.6 mol/L. The degree of crystallization was decreased with increasing the concentration of LiBr. The hydrated crystalline phase of chitosan was formed in the blend film that lithium bromide was removed in the process of casting by neutralization and osmotic action. The crystallinity of this film was increased largely as compared with that of the film without lithium bromide. The complexed blend film formed hydrogel absorbing plenty of water.