The basalt fiber is expected to become a trend for industrial fibers as they have better properties of heat-resistant, non-combustion, absorbent, soundproof, moistureproof, lightweight, corrosion resistant, and high strength properties. Also, the fiber is found to be non-toxic and harmless to the human body. Therefore, in this study, we analyzed the chemical and mineral compositions of powdered sludge of basalt produced at seven sites on Jeju Island for the development of fire resistance insulating material for a building. The results showed that the basalt stone sludge is made from only sodium calcium aluminum silicate and ferridioside components unlike the basalt rock.

본 연구에서는 제주도에서 규모가 가장 큰 항구인 제주항내 퇴적물을 대상으로 PCBs의 분포특성을 연구하였다. 연구 결과, 제주항 내 표층퇴적물에서 PCBs 화합물의 농도범위는 1.62∼4.45 ng/g dw로 낮은 농도로 분포하고 있었고, PCBs의 동족체 패턴 분석을 보면 제주항은 선박 활동으로 유래되는 고염소화된 CBs(Hexa-CBs 이상)이 주로 분포하였다. 퇴적물에서 PCBs 화합물의 분포에 미치는 유기물의 영향을 평가하기 위하여 퇴적물 내 유기탄소 함량과 PCBs 화합물의 농도와의 상관관계를 검토한 결과, R2이 0.8387로 높게 나타나 유기탄소 함량과 PCBs 농도는 매우 유의한 상관성을 보이는 것을 알 수 있었다. PCBs 화합물의 농도분포와 입자크기와의 관계에서 역질, 사질, 니질로 나누어 조사하였는데 니질의 함량이 증가할수록 PCBs의 농도도 높게 분포하였다. 그리고 연구지역의 표층퇴적물에서 분포하고 있는 PCBs의 농도를 국외에서 적용하고 있는 퇴적물오염기준(sediment quality guidenes, SQGs)의 ERL(effect range-low)과 TEL(Threshold Effects Level) 값과 비교한 결과, 훨씬 낮은 값을 보여 생태독성학적 관점에서 저서생물에 미치는 영향은 미미한 것으로 사료된다.

Magnetic activated carbon was prepared by adding a magnetic material to activated carbon that had been prepared from waste citrus peel in Jeju. The adsorption characteristics of an aqueous solution of the antibiotic trimethoprim (TMP) were investigated using the magnetic activated carbon, as an adsorbent, and response surface methodology (RSM). Batch experiments were carried out according to a four-factor Box-Behnken experimental design affecting TMP adsorption with their input parameters (TMP concentration: 50～150 mg/L; pH: 4～10; temperature: 293～323 K; adsorbent dose: 0.05～0.15 g). The significance of the independent variables and their interaction was assessed by ANOVA and t-test statistical techniques. Statistical results showed that TMP concentration was the most effective parameter, compared with others. The adsorption process can be well described by the pseudo-second-order kinetic model. The experimental isotherm data followed the Langmuir isotherm model. The maximum adsorption capacities of TMP, estimated with the Langmuir isotherm model were 115.9-130.5 mg/g at 293-323 K. Also, both the thermodynamic parameters, △H and △G, have both positive values, indicating that the adsorption of TMP by the magnetic activated carbon is an endothermic reaction and proceeds via an involuntary process.

In order to photocatalytically treat organic matter (CODCr) and chromaticity effectively, chemical coagulation and sedimentation processes were employed as a pretreatment of the leachate produced from landfill in Jeju Island. This was performed using FeCl3･6H2O as a coagulant. For the treated leachate, UV/TiO2 and UV/TiO2/H2O2 systems were investigated, using 4 types of UV lamps, including an ozone lamp (24 W), TiO2 as a photocatalyst, and/or H2O2 as an initiator or inhibitor for photocatalytic degradation. In the chemical coagulation and sedimentation process using FeCl3･6H2O, optimum removal was achieved with an initial pH of 6, and a coagulant dosage of 2.0 g/L, culminating in the removal of 40% CODCr and 81% chromaticity. For the UV/TiO2 system utilizing an ozone lamp and 3 g/L of TiO2, the optimum condition was obtained at pH 5. However, the treated CODCr and chromaticity did not meet the emission standards (CODCr: 400 mg/L, chromaticity: 200 degrees) in a clean area. However, for a UV/TiO2/H2O2 system using 1.54 g/L of H2O2 in addition to the above optimum UV/TiO2 system, the results were 395 mg/L and 160 degrees, respectively, which were within the emission standard limits. The effect of the UV lamp on the removal of CODCr, and chromaticity of the leachate decreased in the order of ozone (24 W) lamp > 254 nm (24 W) lamp > ozone (14 W) lamp > 254 nm (14 W) lamp. Only CODCr and chromaticity treated with the ozone (24 W) lamp met the emission standards.

Raw leachates from three landfills and treated leachates from two landfills on Jeju Isalnd were analyzed for ten perfluorinated compounds (PFCs) detected in aquaruc environments. The leachates were collected six times in 2014 and 2015. Among the ten PFCs, three were not detected, namely perfluoroundecanoic acid (PFUnDA), perfluorododecanoic acid (PFDoDA), and perfluorodecane sulfonate (PFDS). The total concentrations of PFCs ranged as 724-3313 ng/L (mean 1999 ng/L) in raw leachates and from less than the limit of quantification (LOQ) to 394 ng/L (mean 133.2 ng/L) in treated leachates. The domonant compounds measured were perfluorooctanoic acid (PFOA) (mean contribution 37.7%) and perfluorobutane sulfonate (PFBS) (mean contribution 38.2%) in raw leachates, and PFOA (mean contribution 40.7%), perfluorohexanoic acid (PFHxA) (mean contribution 27.3%) and PFBS (mean contribution 26.5%) in treated leachates. No significant correlations were observed between total/several individual PFCs and leachate pH and CODCr, which may be due to complex chemical nature of landfill leachates and characteristics of waste and landfills.

The characteristics of ammonia-nitrogen (NH4 +-N) adsorption by a zeolitic material synthesized from Jeju scoria using the fusion and hydrothermal method was studied. The synthetic zeolitic material (Z-SA) was identified as a Na-A zeolite by X-ray diffraction, X-ray fluorescence analysis and scanning electron microscopy images. The adsorption of NH4 +-N using Jeju scoria and different types of zeolite such as the Z-SA, natural zeolite, and commercial pure zeolite (Na-A zeolite, Z-CS) was compared. The equilibrium of NH4 +-N adsorption was reached within 30 min for Z-SA and Z-CS, and after 60 min for Jeju scoria and natural zeolite. The adsorption capacity of NH4 +-N increased with approaching to neutral when pH was in the range of 3-7, but decreased above 7. The removal efficiency of NH4 +-N increased with increasing Z-SA dosage, however, its adsorption capacity decreased. For initial NH4 +-N concentrations of 10-200 mg/L at pH 7, the adsorption rate of NH4 +-N was well described by the pseudo second-order kinetic model than the pseudo first-order kinetic model. The adsorption isotherm was well fitted by the Langmuir model. The maximum uptake of NH4 +-N obtained from the Langmuir model decreased in the order of Z-CS (46.8 mg/g) > Z-SA (31.3 mg/g) > natural zeolite (5.6 mg/g) > Jeju scoria (0.2 mg/g).

The characteristics of heavy metal ion (Ni2+, Zn2+, and Cr3+) adsorption by zeolite synthesized from Jeju scoria using the fusion and hydrothermal method, were studied. The synthetic zeolite was identified as a Na-A zeolite by X-ray diffraction analysis and scanning electron microscopy images. The equilibrium of heavy metal ion adsorption by synthetic zeolite was reached within 60 min for Ni2+ and Zn2+, and 90 min for Cr3+. The uptake of heavy metal ions increased with increasing pH in the range of pH 3-6 and the uptake decreased in the order of Cr3+ > Zn2+ > Ni2+. For initial heavy metal concentrations of 20-250 mg/L at nonadjusted pH, the adsoption of heavy metal ions was well described by the pseudo second-order kinetic model and was well fitted by the Langmuir isotherm model. The maximum uptake of heavy metal ions obtained from the Langmuir model, decreased in the order of Zn2+ > Ni2+ > Cr3+, differing from the effect of pH on the uptake, which was mainly based on the different pH of the solutions.

The adsorption and leaching characteristics of five ionic pesticides including four acidic pesticides (2,4-D, dicamba, MCPA, and MCPP) and one amphoteric pesticide (imazaquin) in agricultural soils were investigated. Soils around spring waters that were heavily affected by pesticide run-off and soils around wells considering the regional characteristics in Jeju Island were collected at 24 stations. The Freundlich constant, KF value, which is a measure of the adsorption capacity, decreased in the order of 2,4-D > MCPA > MCPP > dicamba > imazaquin. The adsorption capacity of these ionic pesticides decreased with increasing pH owing to the effects of ionization of pesticides and different ionizable functional groups of soils. The leaching of ionic pesticides in the soil column showed a reverse relationship with their adsorption in soils, namely, the ionic pesticides were leached more quickly for the pesticides with lower adsorption capacity. The groundwater contamination potential of the ionic pesticides was evaluated in the order of imazaquin > MCPA > MCPP > dicamba > 2.4-D according to the groundwater ubiquity score based on soil Koc and the half-life of the pesticide.

The adsorption properties of Cs+ and Cu2+ ions were evaluated by using a polysulfone scoria zeolite (PSf-SZ) composite with synthetic zeolite synthesized from Jeju volcanic rocks (scoria). In order to investigate the adsorption properties, various parameters, such as pH, contact time, reaction rate, concentration, and temperature in aqueous solutions, were evaluated by tests carried out in batch experiments. The adsorption capacities of Cs+ and Cu2+ ions increased between pH 2 but achieved equilibrium at pH 4 and above. The adsorption rate increased rapidly up to the initial 24 h, after which it plateaued ; the adsorption rate then sustained at equilibrium from 48 h. The adsorption kinetics of Cs+ and Cu2+ ions were described better by the pseudo-second-order kinetic model than the pseudo-first-order kinetic model. The Langmuir model fitted the adsorption isotherm data better than the Freundlich model. The maximum adsorption capacities of Cs+ and Cu2+ ions obtained from the Langmuir model were 53.8 mg/g and 84.7 mg/g, respectively. The calculated thermodynamic parameters showed that the adsorption of Cs+ and Cu2+ ions on PSf-SZ was feasible, spontaneous and endothermic reaction.

The adsorption characteristics of bisphenol A (BPA) were investigated using activated carbon based on waste citrus peel (which is abandoned in large quantities in Jeju Island), denoted as WCP-AC, and surface-modified with various P2O5 concentrations (WCP-SM-AC). Moreover, coconut-based activated carbon (which is marketed in large amounts) was surface-modified in an identical manner for comparison. The adsorption equilibrium of BPA using the activated carbons before and after surface modification was obtained at nearly 48 h. The adsorption process of BPA by activated carbons and surface-modified activated carbons was well-described by the pseudo second-order kinetic model. The experimental data in the adsorption isotherm followed the Langmuir isotherm model. With increasing P2O5 concentration (250-2,000 mg/L), the amounts of BPA adsorbed by WCP-SM-AC increased till 1,000 mg/L of P2O5; however, above 1,000 mg/L of P2O5, the same amounts adsorbed at 1,000 mg/L of P2O5 were obtained. With increasing reaction temperature, the reaction rate increased, but the adsorbed amounts decreased, especially for the activated carbon before surface modification. The amounts of BPA adsorbed by WCP-AC and WCP-SM-AC were similar in the pH range of 5-9, but significantly decreased at pH 11, and increased with increasing ionic strength due to screening and salting-out effects.

The purpose of this study was to minimize salt water intrusion into freshwater aquifers and limit the development of freshwater aquifers, by selecting an appropriate excavation depth of in the western coastal area of Jeju Island. The study site was mostly basaltic lava, which was mainly composed of trachy basalt. A vertical logging test was conducted to investigate the vertical distribution of the groundwater and saline groundwater interface in the study well. It was found that freshwater groundwater, saline groundwater, and freshwater groundwater are distributed from the surface to approximately 16 m, 16∼50 m, and 50∼60 m, below the ground, respectively. In order obtain saline groundwater and minimize the inflow of freshwater into this well, the drilling depth should be limited in the range of 16∼50 m from the surface. Thus, saline groundwater well development should be carried out with reference to the measurement results, which depend on the drilling depth and EC (electrical conductivity) obtained with drilling apparatus for geology and ground handling.

Agricultural soils around springwaters heavily affected by pesticide run-off and around wells considering the regional characteristics were collected at 24 stations in Jeju Island, and the physicochemical properties and adsorption and leaching characteristics of four nonionic pesticides (diazinon, fenitrothion, alachlor, and metalaxyl) were investigated. The values of the major soil factors affecting the adsorption and leaching of pesticides, namely, soil pH(H2O), organic matter content, and cation exchange capacity (CEC), were in the range of 4.64 ∼ 8.30, 0.9 ∼ 13.1% and 12.7 ∼ 31.7 meq/100 g, respectively. The Freundlich constant, KF value, which gives a measure of the adsorption capacity, decreased in the order of fenitrothion > diazinon > alachlor > metalaxyl, which was identical to their lower water solubility. Among the collected soils, the KF value was very highly correlated with organic matter content (r2 = 0.800 ∼ 0.876) and CEC (r2 = 0.715 ∼ 0.825) and showed a high correlation with clay content (r2 = 0.473 ∼ 0.575) and soil pH(H2O) (r2 = 0.401 ∼ 0.452). The leaching of pesticides in the soil column showed a reverse relationhip with their adsorption in soils, i.e., the pesticides leached more quickly for the soils with lower values of organic matter content and CEC among the soils and for the pesticides with higher water solubility.

For 26 soil series distributed more than 1% among 63 soil series in Jeju Island, natural uncultivated soil samples were collected. For these soils, the chemical speciation of eight heavy metals (Cd, Cr, Cu, Mn, Ni, Pb, V, and Zn) was examined. Further, the Plant Bioavailability (PB) and Mobility Factor (MF) of these heavy metals were evaluated using Tessier’s 5-step sequential extraction method (exchangeable, carbonate, reducible (bound to Fe/Mn oxides), oxidizable (bound to organic matter), and residual fraction). The main form present was residual fraction for Cd and Zn; residual and oxidizable fractions for Cr, Cu, Ni, and Pb; reducible fraction for Mn; and carbonate fraction for V. The average plant availability and average mobility factor were found to be V (57.37%) > Zn (12.49%) > Cd (11.76%) > Cu (11.19%) > Pb (9.37%) > Cr (9.09%) > Mn (3.13%) > Ni (2.63%), and Mn (61.04%) > V (59.94%) > Zn (31.54%) > Cd (17.65%) > Cr (15.66%) > Ni (13.89%) > Pb (13.80%) > Cu (13.53%), respectively.

In order to investigate the adsorption characteristics for Sr ion using the Na-X zeolite synthesized from coal fly ash, batch tests and response surface analyses were carried out. The adsorption kinetic data for Sr ions, using Na-X zeolite, fitted well with the pseudo-second-order model. The uptake of Sr ions followed the Langmuir isotherm model, with a maximum adsorption capacity of 196.46 mg/g. Thermodynamic studies were conducted at different reaction temperatures, with the results indicating that Sr ion adsorption by Na-X zeolite was an endothermic (ΔHo>0) and spontaneous (ΔGo<0) process. Using the response surface methodology of the Box-Behnken method, initial Sr ion concentration (X1), initial temperature (X2), and initial pH (X3) were selected as the independent variables, while the adsorption of Sr ions by Na-X zeolite was selected as the dependent variable. The experimental data fitted well with a second-order polynomial equation by multiple regression analysis. The value of the determination coefficient (R2=0.9937) and the adjusted determination coefficient (adjusted R2=0.9823) was close to 1, indicating high significance of the model. Statistical results showed the order of Sr removal based on experimental factors to be initial pH > initial concentration > temperature.

Measurements of polychlorinated biphenyls (PCBs) were taken in surface sediments inside Seogwipo and Hallim Harbors of Jeju Island, Korea, to evaluate their distribution. These harbors typically have heavy ship traffic. The samples were collected three times (in June, October, and December, 2013). PCB concentrations in sediments from Seogwipo Harbor were higher than in those from Hallim Harbor, but both levels were very low, compared with those in other parts of the world. Sedimentary PCB levels had a strong correlation with organic carbon and fine granule mud content. PCB concentration values in the examined surface sediments were much lower than Sediment Quality Guidelines (SQGs) such as ER-L (Effect Rrange-Low), TEL (Threshold Effects Level) and ISQG (Interim Sediment Quality Guideline)-low value applied in countries, such as USA, Canada, and Australia. This suggests that the PCBs did not have significant biological effects on benthic organisms in the marine environment.

This study evaluates the adsorption properties of Sr ions in an aqueous solution of the synthetic zeolite (Z-Y1) prepared using coal fly ash generated from a thermal power plant. In order to investigate the adsorption characteristics, the effects of various parameters such as the initial concentrations of Sr ion, contact time, and solution pH were investigated in a batch mode. The Langmuir and Redlich-Peterson model fitted the adsorption isotherm data better than the Freundlich model. The maximum adsorption capacity of Sr ions, as determined the Langmuir model, was 181.68 mg/g. It was found that by varying the Sr ion concentration, pH, and temperature, the pseudo-second-order kinetic model describes the adsorption kinetics of the Sr ion better than the pseudo-first-order kinetic model. The calculated thermodynamic parameters of ΔH0 and ΔG0 showed that the adsorption of Sr ions on Z-Y1 was occurred through a spontaneous and an endothermic reaction. We found that the adsorption of Sr ions by Z-Y1 was more affected by pH than by temperature and Sr ion concentration.

Zeolite (FZ) prepared using coal fly ash from an Ulsan industrial complex was immobilized with polysulfone (PS) to fabricate PS-FZ beads. The prepared PS-FZ beads were characterized by scanning electron microscopy and Fourier transform infrared spectroscopy. The optimum ratio for preparing PS-FZ beads was 1 g of PS to 2 g of FZ. The removal efficiencies of Sr and Cu ions by the PS-FZ beads increased as the solution pH increased and nearly reached a plateau at pH 4. A pseudo-second-order model morel fit the adsorption kinetics of both ions by the PS-FZ beads better than a pseudo-first-order model. The Langmuir isotherm model fit the equilibrium data well. The maximum adsorption capacities calculated from the Langmuir isotherm model were 46.73 mg/g and 62.54 mg/g for the Sr and Cu ions, respectively. Additionally, the values of thermodynamic parameters such as free energy (ΔG˚), enthalpy (ΔH˚) and entropy (ΔS˚) were determined. The results implied that the prepared PS-FZ beads could be interesting an alternative material for Sr and Cu ion removal.

Zeolite (FZ), prepared from fly ash, was immobilized with polyacrylonitrile (PAN) to fabricate PAN/FZ beads. The prepared PAN/FZ beads were characterized by scanning electron microscopy, thermogravimetric analysis, and Fourier transform infrared spectroscopy. The optimum ratio to prepare PAN/FZ beads was 0.3 g of PAN to 0.3 g of FZ. The diameter of the prepared PAN/FZ beads was about 3 mm. Sr and Cu ion adsorption experiments were conducted with PAN/FZ beads. A pseudo-second-order model fit the kinetic data for Sr and Cu ion adsorption by PAN/FZ beads well. The equilibrium data fitted well with the Langmuir isotherm model, and the maximum adsorption capacities were 96.5 mg/g and 74.6 mg/g for the Sr and Cu ions, respectively. Additionally, the values of thermodynamic parameters such as Gibbs free energy (ΔGo), enthalpy (ΔHo) and entropy (ΔSo) were determined. The positive values of ΔHo revealed the endothermic nature of the adsorption process and the negative values of ΔGo were indicative of the spontaneity of the adsorption process.

The aim of this study was to evaluate the occurrence of vanadium in Jeju Island groundwater, focusing on the spatio-temporal patterns and geochemical controlling factors of vanadium. For this, we collected two sets of groundwater data: 1) concentrations of major constituents of 2,595 groundwater samples between 2008 and 2014 and 2) 258 groundwater samples between December 2006 and June 2008. The concentrations of groundwater vanadium were in the range of 0.2 71.0 μg/L (average, 12.0 μg/L) and showed local enrichments without temporal/seasonal variation. This indicated that vanadium distribution was controlled by 1) the geochemical/mineralogical composition and dissolution processes of original materials (i.e., volcanic rock) and 2) the flow and chemical properties of groundwater. Vanadium concentration was significantly positively correlated with that of major ions (Cl-, Na+, and K+) and trace metals (As, Cr, and Al), and with pH, but was negatively correlated with NO3-N concentration. The high concentrations of vanadium (>15 μg/L) occurred in typically alkaline groundwater with high pH ( 8.0), indicating that a higher degree of water-rock interaction resulted in vanadium enrichment. Thus, higher concentrations of vanadium occurred in groundwater of Na-Ca-HCO3, Na-Mg-HCO3 and Na-HCO3 types and were remarkably lower in groundwater of Na-Ca-NO3(Cl) type that represented the influences from anthropogenic pollution.

To understand the characteristics of vanadium leaching from soils formed by the weathering of basalts, paleo soil at Gosan, Jeju Island, Korea, and several present-day soils from neighboring areas were collected. Leaching experiments were carried out by two approaches: 1) batch experiments under various geochemical conditions (redox potential (Eh) and pH) and 2) continuous leaching experiments under conditions similar to those of natural environments. From the batch experiments, leached vanadium concentrations were highest under alkaline (NaOH) conditions, with a maximum value of 2,870 μg/L, and were meaningful (maximum value, 114 μg/L) under oxidizing (H2O2) conditions, whereas concentrations under other conditions (acidic-HCl, neutral-NaHCO3, and reducing-Na2S2O3) were negligible. This indicated that the geochemical conditions, in which soil-water reactions occurred to form groundwater with high vanadium concentrations, were under alkaline-oxidizing conditions. From the continuous leaching experiments, the pH and leached vanadium concentrations of the solution were in the ranges of 5.45 5.58 and 6 9 μg/L, respectively, under CO2 supersaturation conditions for the first 15 days, whereas values under O2 aeration conditions after the next 15 days increased to 8.48 8.62 and 9.7 12.2 μg/L, respectively. Vanadium concentrations from the latter continuous leaching experiments were similar to the average concentration of groundwater in Jeju Island (11.2 μg/L). Furthermore leached vanadium concentrations in continuous leaching experiments were highly correlated with pH and Al, Cr, Fe, Mn and Zn concentrations. The results of this study showed that 1) alkaline-oxidizing conditions of water-rock (soil) interactions were essential to form vanadium-rich groundwater and 2) volcanic soils can be a potential source of vanadium in Jeju Island groundwater.