The aim of this study is to investigate the sorption/ion exchange of radioactive nuclides such as Cs+ and Sr2+ by synthetic Na-micas. In order to prepare Na-micas, two natural micas (phlogopite and biotite) were used as precursor materials. XRD, SEM, and EDS analyses were used to examine material characterization of synthetic Na-micas. Analyses of materials revealed that Na-micas were successfully obtained from natrual micas by K removal treatment. On the other hand, single solute (Cs or Sr) and bi-solute (Cs/Sr) sorption experiments were carried out to determine sorption capacity of Na-micas for Cs and Sr under different pH and ionic strength conditions. Uptake of Cs and Sr by micas in bi-solute system was lower than in single-solute system. Additionally, Langmuir and Langmuir competitive models were applied to describe sorption isotherm of Na-micas. bi-solute system was well described by Langmuir competitive models. For the results obtained in this study, Na-micas could be promising sorbents to treat multi-radioactive species from water and groundwater.

In order to treat groundwater containing high levels of nitrate, nitrate reduction by nano sized zero-valent iron (nZVI) was studied using batch experiments. Compared to nitrate removal efficiencies at different mass ratios of nitrate/Fe0, the removal efficiency at the mass ratio of 0.02% was the highest(54.59%). To enhance nitrate removal efficiency, surface modification of nZVI was performed using metallic catalysis such as Pd, Ni and Cu. Nitrate removal efficiency by Cu-nZVI (at catalyst/Fe0 mass ratio of 0.1%) was 66.34%. It showed that the removal efficiency of Cu-nZVI was greater than that of the other catalysts. The observed rate constant (kobs) of nitrate reduction by Cu-nZVI was estimated to 0.7501 min-1 at the Cu/Fe mass ratio of 0.1%. On the other hand, TEM images showed that the average particle sizes of synthetic nZVI and Cu-nZVI were 40~60 and 80~100 nm, respectively. The results imply that catalyst effects may be more important than particle size effects in the enhancement of nitrate reduction by nZVI.

Pollutants generated by the biodegradation of livestock carcasses have the potential for contamination of the environment. Hence, livestock mortalities burial has been banned in the EU. In spite of the hazard, research on the biodegradation of livestock carcasses is lacking. In this study, five lysimeters were used to evaluate the enhanced biodegradation of organic materials in livestock mortalities burial. Lysimeter 1(control), lysimeter 2(grinding of livestock carcass), lysimeter 3(anaerobic microorganisms), lysimeter 4(Corynebacterium glutamicum in anaerobic condition) and lysimeter 5(Corynebacterium glutamicum in aerobic condition) were operated with temperature control. The degradation efficiencies of livestock carcass in the lysimeters were evaluated based on total organic carbon balance. The degradation efficiencies of ground livestock carcass were 1.9 times more than those of livestock carcass without grinding. In anaerobic condition, anaerobic microorganisms were more effective compared with Corynebacterium glutamicum on the biodegradation of livestock carcasses. However, the degradation efficiencies with Corynebacterium glutamicum in aerobic condition were significantly influenced on the biodegradation of livestock carcasses. Even if it would be helpful to degrade the livestock carcass in aerobic condition in terms of stabilization, potential risks on the environment by odor and bioaerosol must be solved.

In this research, equilibrium of adsorption and kinetics of As(V) removal were investigated. The coal mine drainage sludge(CMDS) was used as adsorbent. To find out the physical and chemical properties of CMDS, XRD (X-ray diffraction), XRF (X-ray fluorescence spectrometer) analysis were carried out. The CMDS was consist of 70% of goethite and 30% of calcite. From the results, an adsorption mechanism of As(V) with CMDS was dominated by iron oxides. Langmuir adsorption isotherm model was fitted well more than Freundlich isotherm adsorption model. Adsorption capacities of CMDS 1 was not different with CMDS 2 on aspect of amounts of arsenic adsorbed. The maximum adsorption amount of two CMDS were respectively 40.816, 39.682 mg/g. However, the kinetic of two CMDS was different. The kinetic was followed pseudo second order model than pseudo first order model. Concentrations of arsenic in all segments of the polymer in CMDS 2 does not have a constant value, but the rate was greater than the value of CMDS 1. Therefore, CMDS 2, which is containing polymer, is more effective for adsorbent to remove As(V).