In order to improve the thermal stability of PAN-based electrospun fibers, AP-PER-MEL and TiO2 were added in to the fibers as additives. The polymer composite with uniformly mixed additional agents was obtained. In case of non-treated sample, the fibers were burn off completely with high rate within 620℃. But in case of treated samples (EF-M and EF-MT), it is sure that the thermal stability was improved by studying TGA data and ISO flammability test about 20 and 30%, respectively. A synergy effect of adding two kinds of agents (AP-PER-MEL and TiO2) into PAN-based electrospun fibers was confirmed. Through SEM images, it is confirmed that the fiber shape can be kept even after addition of agents (AP-PER-MEL and TiO2). Finally the thermal stability of fibers was largely developed with keeping the nature of PAN-based fibers effectively.

A nanocomposite consisting of Fe3O4 and MWCNT was produced via sol-gel technique using FeCl3 along with MWCNT by calcination at 300℃. The degradation effect of rhodamine B dye has been investigated under UV illumination in a darkroom. The degradation reaction was studied by monitoring the discoloration of dye as a function of irradiation time using UV-visible spectrophotometeric technique. The Fe3O4-MWCNT samples have continuous degradation ability under the UV illumination with the first order kinetics and the dye removal was better than in the pristine Fe3O4. The resultant composite catalyst was found to be efficient for the photo-Fenton reaction of the dye.

The adsorption and reduction of Cr (VI) to Cr (III) by surface modified activated carbon (AC) in an aqueous solution was studied. The effects of surface modifications on the properties of the carbons were investigated by the analysis of specific surface area, carbon surface pH, acid/base surface values and functional groups. In order to understand the Cr(VI) adsorption and reduction ratio from Cr(VI) to Cr(III), the Cr adsorption capacity of AC was also measured and discussed by using inductively coupled plasma and UV spectrophotometer. The modifications bring about substantial variation in the chemical properties whereas the physical properties such as specific surface area, pore volume and pore size distribution nearly were not changed. Total Cr adsorption efficiency of as-received activated carbon (R-AC) and nitric acid treated activated carbon (N1-AC and N2-AC) were recorded on 98.2, 99.7 and 100%. Cr(III) reduction efficiency of R-AC increased largely from 0.4% to 28.3% compared to N1-AC and N2-AC.