This study was performed to investigate the possible uses of waste sludge for the removal of heavy metal ions. The adsorption experiments were conducted with wastes such as sewage treatment sludge, water treatment sludge and oyster shell to evaluate their sorption characteristics. Heavy metals selected were cadmium, copper and lead. In the sorption experiments on the sewage treatment sludge, water treatment sludge, oyster shell and soil, sorption occurred in the beginning and it reached equilibrium after 40 minutes on the oyster shell and 4 hour on the sewage treatment sludge and water treatment sludge. Results of Freundlich isotherms indicated that sewage treatment sludge could be properly used as an adsorbent for heavy metals and sorption strength of heavy metals was in the order of Pb > Cu > Cd. In the influence of pH on the adsorbents, sorption rate was more than 80% in pH 4 and most of heavy metals were adsorbed in pH 9. Adsorption rate of Cd decreased with decreasing pH and then adsorption rate of Cu was lower in soil.

To obtain the safety evaluation of the ginseng, residues of heavy metals in culture environment of ginseng on Punggi and Sangju, Kyeongbuk are surveyed. The concentration for component of ginseng on Punggi and Sangju were 14.12 mg/kg and 15.74 mg/kg, respectively. The concentration for general component such as crude fiber, ash, crude lipid, crude protein, carbohydrate, of ginseng were coincided between Punggi and Sangju. The concentration for As, Pb, Cd, and Hg in soil on Punggi were 14.24 ppb, 43.13 ppb, 8.73 ppb and 0.82 ppb, respectively. The concentration for As, Pb, Cd, and Hg in soil on Sangju were 19.20 ppb, 54.82 ppb, 15.90 ppb and 1.04, respectively. Residual heavy metals are not polluted in the soil with culture ginseng on Punggi and Sangju. The concentration for As, Pb, Cd, and Hg with ginseng on Punggi were 29.30ppb, 21.78 ppb, 1.32 ppb and 2.72 ppb, respectively. The concentration for As, Pb, Cd, and Hg with ginseng on Sangju were 3.22 ppb, 24.43 ppb, 1.44 ppb and 4.74 ppb, respectively. Also the detection concentration for As, Pb, Cd, and Hg in ginseng were also lower than the Korea Food & Drug Administration advisory level for heavy metal in herbal medicines. Residual heavy metals are not polluted in the ginseng on Punggi and Sangju at Kyeongbuk, Korea.

Waste sludge may be used to recovery wastewater contaminated with heavy metals. The waste sludge is an inexpensive readily available source of biomass for biosorption with metal-bearing wastewater. The biosorption of heavy metals such as Pb(II), Cu(II), Cr(II), and Cd(II) onto waste sludge was investigated in batch experiments and waste sludge loaded heavy metals was separated by dissolved air flotation. The biosorption equibria of heavy metals could be described by Langmuir and Freundich isotherms. The adsorption capacity for waste sludge was in the sequence of Pb(II)>Cr(II)>Cu(II)>Cd(II). The system attained equilibrium about 20 min. The Langmuir and Freundlich adsorption model effectively described the biosorption equilibrium of Cu(II) and Cr(II) ions on waste sludge. Maximum adsorption capacity of Cu(II) and Cr(II) were 196.08 and 158.73 mg/g, respectively. Solid-liquid separation efficiencies were kept above 95% on waste sludge loaded heavy metals, and were decreased with pH increasing.

둥굴레 근경의 증자 및 열처리 중 수용성 고형분 및 Pb, Cd 제거율의 변화를 확인하기 위하여 반응표면분석(RSM)을 활용하였다. 중심합성계획법에 따라 증자시간( min), 볶음온도() 및 볶음시간( min)을 달리하여 16구간으로 제조된 시료의 수용성 고형분 함량, Pb 및 Cd 제거율을 측정하고 회귀분석을 실시하였다. 예측된 가용성 고형분의 최대값은 이었으며, 이때의 증자 및 볶음조건은 증자시간 65.24분, 볶음온도 및 볶음시간 37

The thiophene or furan-containing hexadentate ligands 1,12-bis (2-theophene)-2,5,8,11-tetraazadodecane(Thiotrien ․4HCl) and 1,12-bis (2-furan)-2,5,8,11-tetraazadodecane(Furatrien․4HCl) were synthesized as their tetrahydrochloride salt and characterized by EA, IR, NMR, and Mass spectrum. Their protonation constants (logKnH) and stability constants (logKML) for Cd2+, Pb2+, Zn2+ and Cu2+ ions were determined in aqueous solution by potentiometry and compared with 1,12-bis(2-pyridyl)-2,5,8,11-tetra-azadodecane(Pytrien) of pyridyl-containing ligand. The effect stability constants of ligands and metal ion for removal of heavy metals in aqueous solution were described.

In the removal of heavy metals from the mine deposit using electrokinetic processes, the effects of operation under both constant current and constant potential conditions were estimated. The results of soil pH distributions for DDW-20 V and DDW-100 ㎃ cases after the electrokinetic remediation tests were observed. In the former case, soil pH was not much changed and kept to almost constant value just little higher than initial soil pH of 3.52, except near the cathode, which was about pH 5. While in the latter case, soil pHs of anode and the cathode regions were less than pH 3 and about 6, respectively. The electroosmotic flow to the cathode increased rapidly till 10 hrs and decreased steadily and then maintained to constant rate until the end of operation at constant current condition. Electric potential gradient was continuously increased to as much as 34.375 V/cm. At the steady state, values of the apparent electric conductivity for DDW-20 V and DDW-100 ㎃ were around 40 ㎲/㎝ and 30 ㎲/㎝, respectively. In the DDW-100㎃ test, Cu, Cd, and Zn except Pb showed the tendency of moving toward the cathode. While in the DDW-20 V case, it was observed that Cu, Zn, and Pb except Cd were not moved to any directions. The results of the tests demonstrated that the electrokinetic soil remediation process could be operated better under constant current condition than constant electric potential condition.

This experiment was carried out to investigate the effects of heavy metals (cadmium, chromium, copper and lead) on the seed germination of Arabidopsis thaliana, and examinated the removal effects of biostone and green tea on the heavy metal toxicity. Cadmium and chromium among the four heavy metals had no effect on the seed germination even in the concentration fifty times higher than in the official standard concentration of pollutant exhaust notified by the Ministry of Environment. However, seeds were not germinated in the concentration of copper ten times higher and in the concentration of lead fifty times higher than the official standard concentration. When seeds were sown in the solutions of lead (15, 20, 25 and 30 mg/L) and copper (15 and 20 mg/L), the seed germination rates were 0% and less than 10%, respectively. However, when biostone (3 g/30 ml) was added, the seed germination rate was 100% in all the concentrations. The germination rate was 100% in distilled water and copper solution (5 mg/L). However, green tea (0.2 g/30 ml) was added, the seed germination rate was 0% in both. The results show that cadmiun and chromium had no effect on the seed germination, but lead and copper decreased the rate of seed germination of Arabidopsis thaliana. Biostone removed heavy metal toxicity, but green tea did not removed heavy metal toxicity during germination.

The new tridentate ligands of nitrogen doner atoms N,N-Bis(2-amino-ethyl)-benzyl-amine·2HCl(BABEA·2HCl) and 2,6-Bis(amino-methyl)-pyridien·2HCl(BAMP·2HCl) were synthesized as their dihydrochloride salts and characterized by EA, IR, Mass and NMR spectroscopy. The protonation constants of the ligands and stability constants for Cd2+, Pb2+, Zn2+and Cu2+ ions were determined by potentiometric titration in aqueous solutions and compared with those of analogous ligands. The effect stability constants of ligands and metal ions for removal of heavy metals in aqueous solution were described.

Electrokinetic remediation technique offers the opportunity to extract heavy metals from soils with high plasticity. The experiment demonstrated the applicability of electrokinetic remediation on metal-mining deposit and the decision of the enhancement method for four kinds of bench-scale studies. According to the sequential extraction of heavy metals in the "I" mining deposit, Pb and Cu were mostly associated with residual fraction and Zn and Cd were associated with water soluble and residual fraction. Therefore, removable fractions by electrokinetic technology was determined by the sum of the fraction of water soluble and exchangeable, which is Cu : 19.53 %, Pb : 1.42 %, Cd : 52.82 %, Zn : 57.28 %, respectively. When considering electrical potential, volume of effluent, soil pH, and eliminated rate of contaminant, results determined by sum of each weight were Citric aic+SDS (13) > 0.1N HNO3 (10) > HAc (8) > DDW (4). Therefore, citric acid and SDS mixed solution was determined the best enhancing agent for the remediation of metal mining deposit.

This study was conducted to determine the contents of heavy metals in leaves of roadside trees according to different growth stages in Daegu city. The orders of heavy metal contents in leaves of roadside tree and soil were Fe＞Mn＞Zn＞Pb＞Cu＞Cr＞Cd and Fe＞Mn＞Zn＞Cu＞Pb＞Cr＞Cd, respectively. The contents of heavy metals in leaves of roadside trees and soil showed an increasing tendency as the levels of traffic volume increased. The contents of heavy metals in leaves on October were higher than those on May. Zelkova serrata and Ginkgo biloba showed high contents of Cr, Cd and Pb.

This experiment was carried out to investigate the effects of heavy metals (copper, cadmium, lead and chrome) on the growth of plant and seed germination of Arabidopsis thaliana treated with various concentrations of heavy metals. Cadmium and chrome among the 4 heavy metals had no effect on the growth of stem even in the concentration fifty times higher than the official standard concentration of pollutant exhaust notified by the Ministry of Environment. The official standard concentration of cadmium, however, stimulated the growth of stem in general, increasing leaf size and surface area, although it had no effect on the length of stem. But the growth of stem was decreased about 18% in the official standard concentration of pollutant exhaust of lead and copper. There was no growth of root in the concentration of lead and copper ten times higher than the official standard concentration. Cadmium and chrome had no effect on the seed germination, but lead and copper decreased the rate of seed germination. Seeds were not germinated in the concentration of copper ten times higher than the official standard concentration and in the concentration of lead fifty times higher than the official standard concentration. From this research three peculiar results were obtained. Chrome in the soil did not have much effect on the plant growth and seed germination of Arabidopsis thaliana. Cadmium stimulated the stem growth in an optimum concentration. But lead and copper reduced the plant growth and seed germination even in a small concentration, especially copper had the worse effect.

The toxicity values of various heavy metals were evaluated by acute immobilization and chronic reproduction impairment tests, using Daphnia magna. Acute tests were evaluated by the inhibition of their mobilization after 24hrs without food addition. The tests of reproductive impairment were investigated for 21 days by food addition and exchange of water. The effect of each concentration was assessed by Probit analysis and t-test. The results obtained from this study were as follows : 1) The change of pH and DO was not significant in the acute tests, while, in the reproductive tests, pH was increased by 0.3∼1.4 and DO also increased. 2) The EiG50 values of immobilization to Daphnia magna in artificial fresh water were 0.030㎎/ℓ(Cu), 0.054㎎/ℓ(Cd), 0.12㎎/ℓ(Cr), 0.74㎎/ℓ(Pb), 3.4㎎/ℓ(As) and the NOEiC values were 0.010㎎/ℓ(Cu), 0.018㎎/ℓ(Cd), 0.010㎎/ℓ(Cr), 0.10㎎/ℓ(Pb), and 1.8㎎/ℓ(As). 3) The EiC50 values of reproductive impairment to Daphnia magna were 13.8㎍/ℓ(Cu), 2.9㎍/ℓ(Cd), 15.5㎍/ℓ(Cr), 61.7㎍/ℓ(Pb), 759㎍/ℓ(As), and NOErC values were 0.95㎍/ℓ(Cu), 0.54㎍/ℓ(Cd), 1.2㎍/ℓ(Cd), 7.4㎍/ℓ(Pb), 110㎍/ℓ(As). The results of tests using OECD artificial culture water were more sensitive than natural water for culturing. The presented data show that an artificial culture water is suitable in the experiment of bioassay for assessing the toxicity of materials.

In order to examine the availability and effectiveness of crab shell for the removal of heavy metals in aqueous solution, the crab shell was compared with cation exchange resin (CER), zeolite, granular activated carbon (GAC) and powdered activated carbon (PAC) on aspects of heavy metal removal capacity, rate and efficiency. In the removal of Pb, Cd and Cr, the heavy metal removal capacity of crab shell was higher than those of any other sorbents (CER, zeolite, GAC, PAC), and the order of heavy metal removal capacity was crab shell > CER > zeolite > PAC =～GAC. However, in the removal of Cu, the result of crab shell was slightly lower than that of CER. The initial heavy metal removal rate was affected by the sorts of sorbents and metals. In all heavy metals, the heavy metal removal rate of crab shell was higher than those of any other sorbents. Under the heavy metal concentration of 1.0 mmole/ℓ, the heavy metal removal efficiency of crab shell was maintained as 93∼100 %, which was much higher than those of any other sorbents.

The hydroxyapatite (HAp) for the present study was prepared by precipitation method in semiconductor fabrication and the crystallized at ambient to950℃ for 30min in electric furnace. The ion-exchange characteristics of HAp for various heavy metal ions such as Cd2+, Cu2+, Mn2+, Zn2+, Fe3+, Pb2+, Al3+, and Cr6+ in aqueous solution has been investigated. The removal ratio of various metal ions for HAp were investigated with regard to reaction time, concentration of standard solution, amount of HAp and pH of solution. The order of the ions exchanged amount was as follows: Pb2+, Fe3+>Cu2+>Zn2+>Al3+>Cd2+>Mn2+>Cr6+. The Pb2+ ion was readily removed by the HAp, even in the strongly acidic region. The maximum amount of the ion-exchange equilibrium for Pb2+ ion was about 45 ㎎/gram of HAp. The HAp would seem to be possible agent for the removal of heavy metal ions in waste water by recycling of waste sludge in semiconductor fabrication.

In order to determine the changes of sediment facies and metal levels in surface sediments after the construction of Shiwha Lake, surface sediments were sampled at 8 sites located on the main channel monthly from June, 1995 to August, 1996 and analysed for 12 metals (Al, Fe, Mn, V, Cr, Co, Ni, Cu, Zn, Cd, As and Pb) by ICP/AES and ICP/MS. Two groups of sampling sites (the inner lake with 3 sites and the outer lake with 5 sites) are subdivided by the surface morphology; the inner lake is a shallow channel area with a gentle slope, while the outer lake is relatively deep and wide channel with a steep slope which has many small distributaries. After the construction of dam, fine terrestrial materials were deposited near the outer lake, which resulted in the change of major sediment facies from sandy silt to mud. With the deposition of fine sediments in the outer lake, anoxic water column induced the formation of sulfide compounds with Cu, Cd, Zn and part of Pb. Metal (Cr, Ni, Cu, Zn and Cd) contents in sediments increased up to twice within 2 years after the construction of dam. This is due to the direct input of industrial and municipal wastes into the lake and the accumulation of metals within the lake. In addition, frequent resuspension of contaminated sediments in a shallow part of the lake may make metal-enriched materials transport near the outer lake with fine terrestrial materials. As the enrichment of Cu, Zn, Cd and part of Pb in the Shiwha Lake may be related to the formation of unstable sulfide compounds by sulfate reduction in anoxic water or sediment column, the effect of mixing with open coastal seawater is discussed.