Al₂O₃ catalysts, used for the hydrolysis of perfluorinated compounds (PFCs), have a limitation in that their lifetime is abruptly lowered by the generation of hydrogen fluoride (HF) during the reaction. In the PFCs hydrolysis plants, increasing replacement cycles is one of the major challenges in reducing maintenance costs. In this study, the Ca(OH)₂ layer, which decomposes the HF, was inserted between the Co-Zr/Al₂O₃ catalyst layers to increase the catalyst replacement cycle during the CF4 gas decomposition at 750℃. As a result, the decomposition rate was rapidly recovered through the replacement of the adsorbent, and the time to maintain a decomposition rate more than 90% improved by more than eight times compared to the bare catalyst layer without adsorbent.

A simple and rapid method of fabricating Mg(OH)2 layer by chemical immersion was developed to improve the corrosion resistance of the magnesium alloy AZ31. The fabricated surface was superhydrophobic with a self-assembled monolayer coating of silane. The surface characteristics were evaluated by Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS) and X-ray Photoelectron Spectroscopy (XPS). The average water contact angle and sliding angle were determined to be 160° and 7° respectively as a result of wettability test. Potentiodynamic polarization indicated that both Mg(OH)2 layer and the thin layer of air were effective in improving anti-corrosion. This method which is efficient with regard to time and cost would be useful for magnesium industries and its application