• Journal of Environmental Science International
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• v.12 no.10
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• pp.1055-1060
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• 2003

Adsorption on goethite of individual component from a solution containing phosphate, sulfate, or copper ion was investigated. Competitive adsorption in the binary and ternary solution systems composed of phosphate, sulfate, and copper ions was also investigated. In competitive adsorption systems with phosphate and sulfate ions, the presence of phosphate ion reduced the adsorption of sulfate ion largely. On the other hand, the presence of sulfate ion caused only a small decrease in phosphate adsorption. This result suggests that phosphate ion is a stronger competitor for adsorption on goethite than sulfate ion, which is consistent with the higher affinity of phosphate for the surface compared to sulfate ion. Compared to the results from single-sorbate systems, adsorption of copper ion in the binary system of sulfate ion and copper ion was found to be enhanced in the presence of sulfate ion. Addition of sulfate ion to the binary system of copper ion and phosphate ion resulted in a small enhancement in copper sorption. This result implies that the presence of sulfate ion promotes adsorption of the ternary complex FeOHCuSO$_4$. The adsorption isotherms could be well described by the Langmuir adsorption equation.

• Journal of Environmental Science International
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• v.12 no.9
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• pp.1011-1016
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• 2003

Adsorption of phosphate, sulfate, and copper ion to goethite was investigated. Goethite was prepared in the alkaline solution. In the single adsorbate systems, the final equilibrium plateau reached within 20 min. The adsorption isotherms of the individual ions could be well described by the Langmuir equation. The maximum adsorption capacities (q$\_$max/) were calculated as 0.483 m㏖/g and 0.239 m㏖/g at pH 3 for phosphate and sulfate ion, and 0.117 m㏖/g at pH 6 for copper ion, respectively, In competitive adsorption system with phosphate and sulfate, phosphate ion was a stronger competitor for adsorption on goethite than sulfate ion, which was consistent with higher affinity of phosphate ion for the surface compared to sulfate ion. The existence of sulfate ion enhanced the adsorption of copper ion but the adsorption of sulfate was inhibited when copper ion was present.

• YAKHAK HOEJI
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• v.38 no.2
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• pp.211-217
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• 1994

Copper intoxication and disturbance of copper metabolism induced various oxygen-derived free radicals related damages. The effect of copper ion on xanthine oxidase activity and type conversion of the enzyme which is concerned to generation of reactive oxygen species, was investigated, It was observed that xanthine oxidase activity was increased by addition of copper ion in the reaction mixture in proportional to the concentration of the metal ion until $60\;{\mu}M$, while the enzyme activity was inhibited in higher concentration of copper treatment. On the other hand, xanthine dehydrogenase activity was inhibited by copper ion addition with concentration dependently. Preincubation of enzyme source with $30\;{\mu}M$ of copper ion, which concentration marked increased the xanthine oxidase activity, unchanged the enzyme activity and type conversion compare to control in vitro system. It was also observed that copper induced xanthine oxidase activity and the enzyme type conversion was protected by dithiothreitol and penicillamine. These results indicate that the increment of the type conversion of xanthine oxidase necessarilly need the presence of copper ion in enzyme assay system.

• Journal of Korean Society on Water Environment
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• v.22 no.4
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• pp.626-631
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• 2006

The adsorption features of copper ion have been investigated by taking the barley residue which occurring from the beer production process as an adsorbent. Under the experimental conditions, adsorption equilibrium of copper ion was attained within 30 minutes after the adsorption started and the adsorption reaction was observed to be first order. As the temperature increased, the adsorbed amount of copper ion at equilibrium was also increased, which indicated that the adsorption reaction was endothermic. Based on the experimental results which obtained by varying the temperatures, several thermodynamic parameters for copper adsorption reaction were estimated. Regarding the electrokinetic behavior of barley residue, its electrokinetic potential was observed to be positive below pH 5 and turned into negative above this pH. In the pH range from 1.5 to 4, copper adsorption was found to be increased, which was well explained by the electrokinetic behavior of barley residue in the pH range. When nitrilotriacetic acid, which is a complexing agent, was coexisted with copper ion, equilibrium adsorption of copper ion was decreased and this was presumed to be due to the formation of metal complex. In addition, the adsorbed amount of copper ion was examined to be increased when $KNO_3$ was coexisted, however, it approached a saturated value above a certain concentration of $KNO_3$.

• The Korean Journal of Ecology
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• v.6 no.2
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• pp.106-113
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• 1983

The growth of Korean axolotl., Hynobius leechii, was analyzed in natural water as control group and in six copper ion groups contaminated by 0.1, 0.2, 0.3, 0.4, 0.5, 0.6 ppm of copper ion. The copper ion checks the growth of the axolotl. The axolotl was not survived during 30 days in the copper ion of 0.3ppm, and, in the 0.4ppm the axolotl was not survived during 10 days after hatch. The growth of head width and body length show a convexing increase pattern, while that of hind leg shows a concaving increase pattern. The copper ion checks the development of hind leg. In the growth quantity of head width, body length and hid leg, that of natural water show the most rapid increase pattern, and copper ion groups of 0.1, 0.2, 0.3ppm follow in that order. The coefficient of relative growth($\alpha$) of control group is the greater value, and the copper ion groups of 0.1, 0.2, 0.3ppm follow in that order. The contaminated groups show the negative allometry in the relative growth of the containated groups to the natural water. Body length shows positive allometry, while hind leg shows negative allometry in the relative growth to head width.

• Carbon letters
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• v.8 no.4
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• pp.321-325
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• 2007

The oxygen and nitrogen enriched activated carbons were obtained from modification of commercial activated carbon by using nitric acid, sodium hydroxide and urea. Zeta-potentials of modified activated carbons were investigated in relation to copper ion adsorption. The structural properties of modified activated carbons were not so much changed, but the zeta-potentials and isoelectric points were considerably changed. The zeta-potential of nitric acid modified activated carbon was the most negative than other activated carbons in the entire pH region, and the $pH_{IEP}$ was shifted from pH 4.8 to 2.6, resulted in the largest copper ion adsorption capacities compare with other activated carbons in the range of pH 3~6.5. In case of urea modified activated carbon, copper ion adsorption was larger than that of the as-received activated carbon from pH 2 to pH 6.5 even though the $pH_{IEP}$ was shifted to pH 6.0, it was due to the coordination process operated between nitrogen functional groups and copper ion. The adsorption capacity of copper ion was much influenced by zeta-potential and $pH_{IEP}$ of carbon adsorbent.

• Journal of the Korean Electrochemical Society
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• v.15 no.1
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• pp.41-47
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• 2012

An annular flow type of copper electrolysis reactor was setup in order to generate the copper ions to remove algae in water. The operating characteristics of the reactor and the effect of copper ion on algae have been considered. By controling the applied current, the copper ion concentration could be obtained as desired level and the faradaic efficiency was above 90%. When the flow rate was increased, the copper ion concentration was linearly decreased due to the dilution effect and the effect of concentration overpotential was insignificant. With the increase of pH in water, the copper ion concentration was linearly decreased and not affected by the conductivity of the water. The concentration of chlorophyll-a was sharply decreased with the increase of copper ion concentration. The algae was effectively removed as the copper ion concentration was above 0.2 ppm. There was no difference between the copper ions obtained by dissolving copper sulfate and those produced by copper electrolysis. The algae removal efficiency was above 90% after 5 days as the copper ion concentration was above 0.4 ppm.

• Journal of Environmental Science International
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• v.11 no.9
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• pp.993-999
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• 2002

Waste paper cup was sulfonated to be used as ion exchanger. Removal characteristic of copper and lead ion by prepared ion exchanger was investigated. The sulfonation was conformed by the high intensity band of $SO_3H$ group around 1100~$1160cm^{-1}$. The synthesized ion exchanger had greater removal ability for copper and lead ion than the original waste paper cup. Ion exchange system reached the final equilibrium plateau within 30min. The maximum removal capacities $q_{max}$ were calculated as 9.79mg/g fur copper and 15.95mg/g for lead, respectively. The affinity of lead based on a weight was higher than that of copper. The ion exchange phenomena appeared to follow a typical Freundlich isotherm.

• The Korean Journal of Ecology
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• v.7 no.4
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• pp.232-238
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• 1984

The author hatched the eggs of Korean frog, Rana nigromaculata in natural water, and reared the tadpoles in natural water as control group and in seven copper ion groups contaminated by 0.1, 0.2, 0.3, 0.4, 0.5, 0.7, and 1.0 ppm of copper ion. The influences of copper ion on the growth of the tadpoles were analyzed, and the results were summarized as follows: 1) The copper ion inhibited the growth of the tadpole. 2) The tadpoles were not survived for 20 days in the copper ion of 0.4~0.5ppm, and in the 0.7ppm, the tadpoles were not survived for 1 day after hatch. 3) The critical lethal concentration of Korean tadpole is regarded as 0.6ppm of copper ion. 4) The growth of head with and body length show a convexin increase pattern. 5) In the growth quantity of head width and body length, that of natural water shows the most rapid increase pattern, and that of the copper ion groups 0.1, 0.2, and 0.3ppm follows in that order. 6) The coefficient of relative growth($\alpha$) of control group is the greatest value, and that of the copper ion groups of 0.1, 0.2, and 0.3ppm follows in that order. The natural water shows the positive allometry, the contaminated groups shows the negative allometry in the relative growth of the contaminated groups to the natural water. 7) Body length shows positive allometry in the relative growth to head width.

• Journal of Korean Society of Water and Wastewater
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• v.33 no.2
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• pp.131-140
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• 2019

This study used a packed column reactor and a horizontal flow mesh reactor to examine the removal of copper ions from aqueous solutions using pine bark, a natural adsorbent prepared from Korean red pine (Pinus densiflora). Both equilibrium and nonequilibrium adsorption experiments were conducted on copper ion concentrations of 10mg/L, and the removals of copper ions at equilibrium were close to 95%. Adsorption of copper ions could be well described by both the Langmuir and Freundlich adsorption isotherms. The bark was treated with nitric acid to enhance efficiency of copper removal, and sorption capacity was improved by about 48% at equilibrium; mechanisms such as ion exchange and chelation may have been involved in the sorption process. A pseudo second-order kinetic model described the kinetic behavior of the copper ion adsorption onto the bark. Regeneration with nitric acid resulted in extended use of spent bark in the packed column. The horizontal flow mesh reactor allowed approximately 80% removal efficiency, demonstrating its operational flexibility and the potential for its practical use as a bark filter reactor.